Abstract:
The present invention provides a method for manufacturing a complex the method having: a composition preparation process for preparing a composition containing a polymer having a cationic functional group and a weight average molecular weigh t of 2000 1000000 the pH of the composition being 2.0 11.0; a composite component preparation process for preparing a composite component provided with a component A and a component B an isoelectric point on a surface of the component B being lower by at least 2.0 than an isoelectric point on a surface of the component A and the isoelectric point on the surface of is the component B being 1.0 7.5 the composite component satisfying the relationship: isoelectric point on surface of component B < pH of composite component < isoelectric point on surface of component A; and an imparting process for imparting the composition to the surface of the component A and the surface of the component B of the composite component.
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DESCRIPTION
METHOD FOR MANUFACTURING COMPOSITE BODY AND COMPOSITION
Technical Field
[000 1] The present invention relates to a method for manufacturing a composite body, and a
composition.
Background Ali
[0002] Conventionally, in various technical fields such as the field of electronic devices,
application of a composition containing a polymer to a member has been conducted.
For example, a technique of applying a semiconductor composition that contains a
polymer having two or more cationic functional groups and having a weight average
molecular weight of from 2,000 to 100,000, to an interlayer insulating layer of a
semiconductor device is known (see, for example, International Publication (WO)
20101137711).
DISCLOSURE OF INVENTION
Technical Problem
[0003] Incidentally, when applying a polymer to each of the members of a composite
member including two or more kinds of members, there are cases in which the polymer is
required to remain preferentially (preferably, selectively) on a specific member. An example
of such a composite member is a composite member including an insulating layer as a
member and a conductive part (for example, a wiring, an electrode, or the like) as other
member. In the case of applying a polymer to the composite member according to this
example, it is required that the polymer remains on the insulating layer as much as possible, to
protect the insulating layer and, at the same time, the polymer does not remain on the
conductive pmt as much as possible, to maintain the electrical connectivity in the surface of
the conductive part. Accordingly, when applying a polymer to the composite member, it is
required to achieve both the ease of remaining the polymer on the insulating layer and the
difficulty of remaining the polymer on the conductive part.
[0004] The invention has been made in view of the above circumstances.
Namely, an aspect of the invention is to provide a method for manufacturing a
composite body that can achieve both the ease of remaining the polymer on a specific member
and the difficulty of remaining the polymer on other member, in the manufacture of a
composite body by applying a polymer to the surface of a composite member including two or
1
more kinds of members, the composite body being equipped with the composite member and
the polymer.
Further, another aspect of the invention is to provide a composition containing a
polymer, in which the composition can achieve both the ease of remaining the polymer on a
specific member and the difficulty of remaining the polymer on other member, when applied
to two or more kinds of composite members.
Solution to Problem
[0005] Specific means for addressing the above problems are as follows.
<1> A method for manufacturing a composite body, the method containing:
a composition preparation process of preparing a composition that contains a
polymer having a cationic functional group and having a weight average molecular weight of
from 2,000 to 1 ,000,000, and that has a pH of from 2.0 to 11.0;
a composite member preparation process of preparing a composite member that
includes a member A and a member B, a surface of the member B having an isoelectric point
that is lower than an isoelectric point of a surface of the member A by 2.0 or more and the
isoelectric point of the member B being from 1.0 to 7.5, and that satisfies a relationship: the
isoelectric point of a surface of the member B The method for manufacturing a composite body according to <1>, wherein the
member A contains at least one element selected from the group consisting of Cu, AI, Ti, Ni,
Fe, Sn, Cr, Mn, Ni, Pt, Zn and Mg, and the member B contains silica.
<3> The method for manufacturing a composite body according to <1> or <2>,
wherein the member A contains Cu, and the member B contains silica.
<4> The method for manufacturing a composite body according to any one of <1> to
<3>, wherein a content of sodium and a content of potassium in the composition are each 10
ppb by weight or less, on an elemental basis.
<5> The method for manufacturing a composite body according to any one of <1> to
<4>, the method further comprising a heating process of heating the composite member to
which the composition has been applied, under a condition of a temperature of from 70°C to
125°C.
<6> The method for manufacturing a composite body according to any one of <1> to
<5>, wherein the member B contains a porous material.
<7> The method for manufacturing a composite body according to any one of <1> to
2
<6>, wherein the polymer has a cationic functional group equivalent weight offrom 27 to
430.
<8> The method for manufacturing a composite body according to any one of <1> to
<7>, wherein the polymer is a polyethyleneimine or a derivative of a polyethyleneimine.
<9> The method for manufacturing a composite body according to any one of <1> to
<8>, wherein the polymer has a branching degree of 48% or more.
<1 0> The method for manufacturing a composite body according to any one of <1>
to <9>, wherein the composition further contains a monocarboxylic acid compound.
<11> The method for manufacturing a composite body according to <10>, wherein
the monocarboxylic acid compound does not have a hydroxyl group or an amino group, and
has a van der Waals volume of 40 cm3 /mol or more.
<12> The method for manufacturing a composite body according to any one of <1>
to <11>, wherein the composite member satisfies a relationship: the isoelectric point of a
surface of the member B The method for manufacturing a composite body according to any one of <1>
to <12>, the method further comprising a cleaning process of cleaning the composite member
to which the composition has been applied, with a rinsing liquid at a temperature of from
l5°C to l00°C.
<14> The method for manufacturing a composite body according to <13>, wherein
the rinsing liquid comprises an acid having, in one molecule, at least one of a moiety that
blocks active species or a functional group that forms a bond with the polymer when heated.
<15> The method for manufacturing a composite body according to any one of <1>
to <14>, the method further comprising a high temperature heating process of heating the
composite member to which the composition has been applied, under a condition of a
temperature of from 200°C to 425°C.
<16> The method for manufacturing a composite body according to any one of <1>
to <15>, wherein the composite member comprises a substrate and, on the substrate, a
conductive part as the member A and an insulating layer as the member B.
[0006] <17> A composition that comprises a polymer having a cationic functional group and
having a weight average molecular weight of from 2,000 to 1,000,000 and a branching degree
of 48% or more, and that has a pH of from 2.0 to 11.0, wherein a content of sodium and a
content of potassium in the composition are each 10 ppb by weight or less, on an elemental
basis.
<18> The composition according to <17>, fmiher comprising a monocarboxylic acid
3
compound.
<19> The composition according to <17> or <18>, being a semiconductor sealing
composition.
Advantageous Effects of Invention
[0007] According to the invention, a method for manufacturing a composite body that can
achieve both the ease of remaining the polymer on a specific member and the difficulty of
remaining the polymer on other member, in the manufacture of a composite body by applying
a polymer to the surface of a composite member including two or more kinds of members, the
composite body being equipped with the composite member and the polymer, may be
provided.
Fmiher, according to the invention, a composition containing a polymer, in which the
composition can achieve both the ease of remaining the polymer on a specific member and the
difficulty of remaining the polymer on other member, when applied to two or more kinds of
composite members, may be provided.
BRIEF DESCRIPTION OF DRAWINGS
[0008] Fig. 1 is a conceptual sectional diagram schematically showing a cross section of a
composite member, in one example of the manufacturing method according to the invention.
Fig. 2 is a conceptual sectional diagram schematically showing a cross section of a
composite member, in another example of the manufacturing method according to the
invention.
Fig. 3 is a graph showing the relationship between the soft bake temperature and, the
thickness of the polymer layer on Si and the thickness of the polymer layer on Cu, in
Examples.
Fig. 4 is a graph showing the relationship between the pH of the composition and, the
thickness of the polymer layer on Si and the thickness of the polymer layer on Cu, in
Examples and Comparative Examples.
DESCRIPTION OF EMBODIMENTS
[0009] Hereinafter, the method for manufacturing a composite body of the invention is
described, and in this description, the composition of the invention is also described.
[0010] <>
The method for manufacturing a composite body of the invention (hereinafter, also
referred to as the "manufacturing method of the invention") has a composition preparation
process of preparing a composition that contains a polymer having a cationic functional group
4
__ ::---=/
~ and having a weight average molecular weight of from 2,000 to 1,000,000, and that has a pH
of from 2.0 to 11.0; a composite member preparation process of preparing a composite
member that includes a member A and a member B, a surface of the member B having an
isoelectric point that is lower than an isoelectric point of a surface of the member A by 2.0 or
more and the isoelectric point of the member B being from 1.0 to 7.5, and that satisfies a
relationship: the isoelectric point of a surface of the member B
The composite member preparation process in the invention is a process of preparing
a composite member that includes a member A and a member B, a surface of the member B
having an isoelectric point that is lower than an isoelectric point of a surface of the member A
by 2.0 or more and the isoelectric point of the member B being from 1.0 to 7.5, and that
satisfies a relationship: the isoelectric point of a surface of the member B < the pH of the
composition < the isoelectric point of a surface of the member A.
In the manufacturing method of the invention, this composite member is an object, to
which the composition is applied.
This preparation process is a process provided for convenience.
The preparation in the present process includes not only preparation of a composite
member that is prepared in advance, prior to the application process, but also manufacture of a
composite member, prior to the application process.
[00 16] In the composite member, the isoelectric point in the surface of the member B is
lower than the isoelectric point in the surface of the member A, and the difference between the
two isoelectric points is 2.0 or more.
The difference between the two isoelectric points is preferably 3.0 or more, more
preferably 4.0 or more, and particularly preferably 5.0 or more.
The isoelectric point in the surface of the member A is preferably from 5.0 to 12.0,
and more preferably from 6.0 to 11.0.
The isoelectric point in the surface of the member B is preferably from 1.0 to 6.0, and
more preferably from 1.5 to 4.0.
7
~=q/
~ In the invention, the "isoelectric point" refers to a pH value of the solvent in which
the zeta potential of a substrate surface in water, which is measured in accordance with an
electromigration method, a streaming potential method, an electroosmosis method, or the like,
becomes zero. Fmiher, as examples of the isoelectric point of the surface of a solid,
isoelectric points described in G. A. Parks, Chemical Reviews, vol. 65, pages 177 to 198
(1965) can be described.
[0017] As described above, the composite member satisfies the relationship: the isoelectric
point of a surface of the member B < the pH of the composition < the isoelectric point of a
surface of the member A.
From the viewpoint of more effectively exhibiting the effects of the invention, it is
preferable that the composite member satisfies the relationship: the isoelectric point of a
surface of the member B
The composition preparation process in the invention is a process of preparing a
composition that contains a polymer having a cationic functional group and having a weight
average molecular weight of from 2,000 to 1,000,000, and that has a pH of from 2.0 to 11.0.
Tllis composition preparation process is a process provided for convenience.
The preparation in the present process includes not only preparation of a composition
that is prepared in advance, prior to the application process, but also manufacture of a
composition, prior to the application process.
[0040] The composition in the invention contains a polymer having a cationic functional
group and having a weight average molecular weight of from 2,000 to 1 ,000,000, and has a
pH of from 2.0 to 11.0. Here, the pH indicates the value measured at 25°C. The method
for measuring the pH may be a method using a generally used pH meter or pH test paper. As
an example, a pH meter is dipped in the composition, to measure the pH value. Here, the pH
meter is used on the assumption that calibration has been made by using a pH standard liquid
adjusted with a buffer solution.
In the present process, by applying this composition to the surface of the member A
and the surface of the member B, a polymer layer containing the above polymer is formed on
these surfaces.
[0041] (Polymer)
The polymer in the invention has at least one cationic functional group.
In the invention, due to the interaction between this cationic functional group and the
surface of the member B, the persistent quality of the polymer with respect to the member B
is improved.
It is preferable that the polymer has two or more cationic functional groups in one
15
molecule. By having such a configuration, the polymer is multipoint adsorbed to the surface
of the member B and, as a result, the persistent quality of the polymer layer with respect to the
member B is further improved.
[0042] The cationic functional group is not particularly limited as far as the cationic
functional group is a functional group capable of being positively charged. As the cationic
functional group, a functional group containing a nitrogen atom (a primary nitrogen atom, a
secondary nitrogen atom, a tertiary nitrogen atom, or a quaternary nitrogen atom) is preferable.
The "functional group containing a nitrogen atom" used herein also includes a functional
group that consists of only one nitrogen atom.
[0043] In the invention, the term "primary nitrogen atom" refers to a nitrogen atom bonded
only to two hydrogen atoms and one other atom than a hydrogen atom (for example, the
nitrogen atom contained in the primary amino group (-NH2 group)), or a nitrogen atom (a
cation) bonded only to tlll'ee hydrogen atoms and one other atom than a hydrogen atom.
Further, the term "secondary nitrogen atom" refers to a nitrogen atom bonded only to
one hydrogen atom and two other atoms than a hydrogen atom (for example, the nitrogen
atom contained in the functional group represented by Formula (a) below), or a nitrogen atom
(a cation) bonded only to two hydrogen atoms and two other atoms than a hydrogen atom.
Fmiher, the term "tertiary nitrogen atom" refers to a nitrogen atom bonded only to
tlu·ee other atoms than a hydrogen atom (that is, the nitrogen atom of the functional group
represented by Formula (b) below), or a nitrogen atom (a cation) bonded only to one
hydrogen atom and tlu·ee other atoms than a hydrogen atom.
Moreover, the term "quaternary nitrogen atom" refers to a nitrogen atom (a cation)
bonded only to four other atoms than a hydrogen atom.
In the description above, the "other atom than a hydrogen atom" is not pmiicularly
limited, and may be, for example, a carbon atom, a silicon atom, or the like. A carbon atom
is preferable.
[0044]
H
*--N--* ( a )
/*
*--N
""'*
(b)
[0045] In Formula (a) and Formula (b),* represents a bond position with an atom other than
a hydrogen atom.
Here, the functional group represented by Formula (a) above may be a functional
group that constitutes a pati of a secondary amino group (an -NHRa group; here, Ra represents
16
an alkyl group), or may be a divalent linking group contained in the skeleton of the polymer.
Further, the functional group (that is, a tettiary nitrogen atom) represented by
Formula (b) above may be a functional group that constitutes a pat1 of a tertiary amino group
(an -NRbRc group; here, each ofRb and Rc independently represents an alkyl group), or may
be a trivalent linking group contained in the skeleton of the polymer.
[0046] The weight average molecular weight of the polymer in the invention is from 2,000
to 1,000,000.
The weight average molecular weight being 2,000 or more is advantageous in terms
of adsorptivity ofthe polymer with respect to the member B. Pat1icularly, when the polymer
has two or more cationic functional groups, the polymer is easily multipoint adsorbed to the
member B.
The weight average molecular weight being 1,000,000 or less is also advantageous in
terms of the covering property of the polymer with respect to the member B. Patticularly,
when the member B has a concave pottion, an opening, or the like, the polymer easily enters
the concave portion, the opening, or the like, and the covering property ofthe polymer with
respect to the wall surfaces of the concave portion or the opening is improved.
The weight average molecular weight of the polymer in the invention is preferably
from 2,000 to 600,000, more preferably from 10,000 to 200,000, still more preferably from
20,000 to 200,000, and yet more preferably fi·om 20,000 to 150,000.
[0047] Note that, the weight average molecular weight and the molecular weight distribution
in the invention indicate the weight average molecular weight and molecular weight
distribution in terms of polyethylene glycol standard, which are measured in accordance with
the GPC (Gel Permeation Chromatography) method.
Specifically, the weight average molecular weight and the molecular weight
distribution in the invention are measured using, as the eluent, an aqueous solution having an
acetic acid concentration of 0.5 moi/L and a sodium nitrate concentration of 0.1 moi/L, and
using an analyzer SHODEX GPC-101 and a columnASAHIPAK GF-7M HQ, and are
calculated using polyethylene glycol as a reference standard.
[0048) From the viewpoint of further improving the persistent quality of the polymer with
respect to the surface of the member B, it is preferable that the polymer has a high cation
density. Specifically, the cationic functional group equivalent weight is preferably from 27
to 430, and more preferably from 43 to 200.
Here, the term "cationic functional group equivalent weight" means a weight average
molecular weight per cationic functional group, and is a value (Mw/n) obtained by dividing
the weight average molecular weight (Mw) of a polymer by the number (n) of the cationic
17
functional groups contained in the polymer corresponding to one molecule. The larger the
cationic functional group equivalent weight is, the lower the cationic functional group density
is. Further, the smaller the cationic functional group equivalent weight is, the higher the
cationic functional group density is.
[0049] The polymer may fmther have an anionic functional group or a nonionic functional
group, if necessary.
The nonionic functional group may be a hydrogen bond-accepting group or may be a
hydrogen bond-donating group. Examples of the nonionic functional group may include a
hydroxyl group, a carbonyl group, and an ether group (-0-).
The anionic functional group is not particularly limited as far as the anionic
functional group is a functional group capable of being negatively charged. Examples of the
anionic functional group may include a carboxyl group, a sulfonic acid group, and a sulfuric
acid group.
[0050] Specific examples of the polymer in the invention may include polyalkyleneimine
(for example, a polyalkyleneimine that is a polymer of an alkyleneimine having from 2 to 12
carbon atoms (preferably from 2 to 8 carbon atoms, and more preferably from 2 to 4 carbon
atoms); particularly preferably polyethyleneimine (PEl)), polyallylamine (PAA), polydiallyl
dimethyl ammonium (PDDA), polyvinyl pyridine (PVP), polylysine, polymethyl pyridyl
vinyl (PMPyV), protonated poly(p-pyridyl vinylene) (R-PHPyV), and any derivatives thereof.
Among them, polyalkyleneimine (for example, a polyalkyleneimine that is a polymer
of an alkyleneimine having from 2 to 12 carbon atoms (preferably from 2 to 8 carbon atoms,
and more preferably from 2 to 4 carbon atoms); particularly preferably polyethyleneimine
(PEl)) or a derivative thereof, polyallylamine (PAA), and the like are preferable, and
polyalkyleneimine (for example, a polyalkyleneimine that is a polymer of an alkyleneimine
having from 2 to 12 carbon atoms (preferably from 2 to 8 carbon atoms, and more preferably
from 2 to 4 carbon atoms); pmticularly preferably polyethyleneimine (PEl)) or a derivative
thereof is more preferable.
[0051] Polyethyleneimine (PEl) can be produced by a known method described in Japanese
Patent Application Publication (JP-B) No. 843-8828, JP-B No. 849-33120, Japanese Patent
Application Laid-Open (JP-A) No. 2001-2123958, WO 2010/137711, and the like. A
polyalkyleneimine other than polyethyleneimine can also be produced by a method similar to
the method of producing polyethyleneimine.
[0052] It is also preferable that the polymer in the invention is a derivative of the
polyalkyleneimine described above (a polyalkyleneimine derivative; patticularly preferably, a
polyethyleneimine derivative). The polyalkyleneimine derivative is not pmticularly limited
18
as far as the polyalkyleneimine derivative is a compound that can be produced by using the
above polyalkyleneimine. Specific examples thereof may include a polyalkyleneimine
derivative obtained by introducing an alkyl group (preferably an alkyl group having from 1 to
10 carbon atoms) or an aryl group into a polyalkyleneimine, and a polyalkyleneimine
derivative obtained by introducing a crosslinking group, such as a hydroxyl group, into a
polyalkyleneimine.
These polyalkyleneimine derivatives can be produced by a commonly used method
using the above polyalkyleneimine. Specifically, these polyalkyleneimine derivatives can be
produced in accordance with the method described in, for example, JP-A No. H6-016809 and
the like.
[0053] Further, as the polyalkyleneimine derivative, a highly branched polyalkyleneimine
obtained by increasing the branching degree of a polyalkyleneimine, through reacting a
cationic functional group-containing monomer with the polyalkyleneimine, is also preferable.
Examples of the method for obtaining the highly branched polyalkyleneimine include
a method of reacting a cationic functional group-containing monomer with a
polyalkyleneimine having plural secondary nitrogen atoms in the skeleton, thereby
substituting at least some of the plural secondary nitrogen atoms with the cationic functional
group-containing monomer; and a method of reacting a cationic functional group-containing
monomer with a polyalkyleneimine having plural primary nitrogen atoms at the terminals,
thereby substituting at least some of the plural primaty nitrogen atoms with the cationic
functional group-containing monomer.
Examples of the cationic functional group which may be introduced, in order to
enhance the branching degree, may include an aminoethyl group, an aminopropyl group, a
diaminopropyl group, an aminobutyl group, a diaminobutyl group, and a triaminobutyl group.
From the viewpoint of decreasing the cationic functional group equivalent weight and
increasing the cationic functional group density, an aminoethyl group is preferable.
As the method for obtaining a highly branched polyalkyleneimine, for example, the
method explained in the section "Method of Producing Polymer" described below can be
used.
[0054] The above polyethyleneimine and derivatives thereof may be commercially available
products. For example, those selected as appropriate from polyethyleneimines and
derivatives thereof available from NIPPON SHOKUBAI CO., LTD., BASF, and the like may
be used.
[0055] It is preferable that the branching degree of the polymer in the invention is 48% or
more.
19
When the branching degree is 48% or more, the member B can be suitably protected
by the polymer layer containing this polymer. For example, in the case of performing a
plasma treatment or formation of wiring after the application process, diffusion of a plasma
component or a metal component into the member B can be suppressed more effectively.
The reason why such an effect can be obtained is guessed as follows. Namely, it is guessed
that the molecular chains of the polymer having a branched structure are intertwined each
other, so that the distance between the molecular chains is reduced, and thus, a metal
component, a plasma component, or the like can be efficiently prevented from penetrating
between the molecular chains.
Such an effect is more effectively exhibited, when the member B contains a porous
material.
[0056] Here, the "branching degree" refers to a value determined according to the following
Equation 1.
Equation I
Branching degree(%)= ((number of tertiary nitrogen atoms+ number of quaternary
nitrogen atoms)/(number of secondary nitrogen atoms+ number of tertiary nitrogen atoms+
number of quaternary nitrogen atoms)) x 100
Accordingly, for example, in a case in which the polymer according to the invention
is a polyalkyleneimine, a straight chain polyalkyleneimine is a polyalkyleneimine having a
branching degree of 0%, since the straight chain polyalkyleneimine does not have any tertiary
nitrogen atom or quaternary nitrogen atom; and a polyalkyleneimine in which all the nitrogen
atoms contained in the skeleton portion except the terminals are tertiary nitrogen atoms (that
is, being maximally branched) is a polyalkyleneimine having a branching degree of I 00%.
[0057] The branching degree is preferably 55% or more, more preferably 70% or more, and
patticularly preferably 75% or more.
The upper limit of the branching degree of the polymer is not particularly limited;
and in a case in which the polymer contains a secondary nitrogen atom, the branching degree
is less than I 00%. From the viewpoint of the easiness of synthesis, it is preferable that the
branching degree of the polymer is 95% or less.
[0058] There is no particular limitation as to the method of adjusting the branching degree of
the polymer to 48% or more. Examples of the method include a method of adjusting the
branching degree by the monomer polymerization condition itself in the synthesis of a
polymer, and a method of increasing the branching degree by reacting another
nitrogen-containing compound or an alkyl compound with respect to the primary nitrogen
atom or the secondary nitrogen atom contained in the polymer, to generate a tertiary nitrogen
20
atom or a quaternary nitrogen atom from the primary nitrogen atom or the secondary nitrogen
atom. Specific examples of the latter method are described below as a "method of producing
a polymer".
[0059] More preferably, the polymer has two or more cationic functional groups including at
least one of a tertiary nitrogen atom or a quaternary nitrogen atom.
Here, the "polymer having two or more cationic functional groups including at least
one of a tertiary nitrogen atom or a quaternary nitrogen atom" means a polymer having two or
more cationic functional groups that include at least one of a tertiary nitrogen atom or a
quaternary nitrogen atom as the cationic functional group (that is, a polymer having two or
more cationic functional groups, in which at least one of the two or more cationic functional
groups is at least one of a tertiary nitrogen atom or a quaternary nitrogen atom).
The polymer is preferably a polymer having, as the cationic functional groups, two or
more of at least one of a tertiary nitrogen atom or a quaternary nitrogen atom (particularly
preferably, a tertiary nitrogen atom).
[0060] The polymer may contain a primary nitrogen atom or a secondary nitrogen atom, as
the cationic functional group.
In a case in which the polymer according to the invention contains one or more
primary nitrogen atoms, the propmtion of the amount of primary nitrogen atom to the total
amount of the nitrogen atoms in the polymer is preferably 33% by mole or higher. When the
polymer contains one or more primary nitrogen atoms (particularly, when the propmtion of
the amount of primary nitrogen atom is 33% by mole or higher), the wettability of the
polymer with respect to the member B is futther improved, and the uniformity of the
thickness of the polymer layer is further improved.
Further, in a case in which the polymer contains one or more primary nitrogen atoms,
it is preferable that a nitrogen atom other than a primary nitrogen atom, such as a secondary
nitrogen atom, coexists with the primary nitrogen atom. Herewith, the thickness of the
polymer layer is easily adjusted to an appropriate range.
[0061] Fmther, it is preferable that the polymer in the invention has a structural unit having a
cationic functional group (hereinafter, may be referred to as a "specific structural unit").
In this case, the cationic functional group may be contained in the specific structural
unit as at least a patt of the main chain, or may be contained as at least a patt of a side chain,
or may be contained as at least a patt of the main chain and at least a part of a side chain.
In a case in which the specific structural unit contains two or more cationic
functional groups, the two or more cationic functional groups may be the same as or different
from each other.
21
Fmiher, in a case in which the member B has the polar group described above, it is
preferable that the cationic functional group is contained such that the ratio (hereinafter, may
be referred to as "relative distance between the cationic functional groups") of the length of
the main chain of the specific structural unit relative to the average distance between the
adsorption points (polar groups) of the cationic functional groups present on the member B is
1.6 or less, and more preferably from 0.08 to 1.0. In such an embodiment, the polymer can
be more efficiently multipoint adsorbed to the member B.
[0062] The molecular weight of the specific structural unit is preferably from 30 to 500, and
more preferably from 40 to 200, from the viewpoint of the adsorptivity to the interlayer
insulating layer. Here, the molecular weight of the specific structural unit means the
molecular weight of a monomer that constitutes the specific structural unit.
The specific structural unit preferably has a relative distance between the cationic
functional groups of 1.6 or less and a molecular weight of from 30 to 500, and more
preferably has a relative distance between the cationic functional groups of from 0.08 to 1.0
and a molecular weight offrom40 to 200, from the viewpoint of the adsorptivity to the
interlayer insulating layer.
[0063] Specific examples of the specific structural unit (shuctural unit having a cationic
functional group) include unit structures derived from a cationic functional group-containing
monomer exemplified below.
Specific examples of the cationic functional group-containing monomer include
alkyleneimine, allylamine, diallyl dimethyl ammonium salt, vinylpyridine, lysine, methyl
vinylpyridine, and p-vinylpyridine.
[0064] The alkyleneimine is preferably an alkyleneimine having from 2 to 12 carbon atoms,
and more preferably an alkyleneimine having from 2 to 8 carbon atoms. An alkyleneimine
having from 2 to 4 carbon atoms is particularly preferable.
Fmiher, the alkyleneimine is preferably a substituted or unsubstituted cyclic amine.
Specific examples of the alkyleneimine include ethyleneimine (another name:
aziridine ), propyleneimine (another name: 2-methylaziridine), butyleneimine, pentyleneimine,
hexyleneimine, heptyleneimine, octyleneimine, trimethyleneimine (another name: azetidine),
tetramethyleneimine (another name: pyrrolidine), pentamethyleneimine (another name:
piperidine), hexamethyleneimine, and octamethyleneimine. Among them, ethyleneimine is
patiicularly preferable.
[0065] As the cationic functional group-containing monomer, among the monomers
described above, at least one of an alkyleneimine (preferably, an alkyleneimine having from2
to 8 carbon atoms) or an allylamine is preferable, and an alkyleneimine (preferably, an
22
alkyleneimine having from 2 to 4 carbon atoms, and particularly preferably, ethyleneimine) is
more preferable, from the viewpoint of the adsorptivity to the member B.
[0066] Fmther, it is preferable that the polymer in the invention contains a structural unit
that is derived from an alkyleneimine having from 2 to 8 carbon atoms (more preferably from
2 to 4 carbon atoms) and that contains a te1tiary nitrogen atom, as the specific structural unit
(structural unit having a cationic functional group), from the viewpoint of the adsorptivity to
the member B.
From the viewpoint of easiness of synthesis, it is more preferable that the polymer in
the invention includes a structural unit that is derived from an alkyleneimine having from 2 to
8 carbon atoms (more preferably from 2 to 4 carbon atoms) and that contains a secondary
nitrogen atom, in addition to the "structural unit that is derived from an alkyleneimine having
from 2 to 8 carbon atoms (more preferably from 2 to 4 carbon atoms) and that contains a
tertiary nitrogen atom".
[0067] Moreover, in the case of introducing a cationic functional group by reacting at least
one of the primary nitrogen atom or the secondary nitrogen atom contained in the polymer
with a nitrogen-containing compound, in order to increase the branching degree, examples of
the cationic functional group to be introduced into the polymer may include the cationic
functional groups shown below("*" represents a bond position with a nitrogen atom in the
polymer skeleton), and an aminopropyl group, a diaminopropyl group, an aminobutyl group, a
diaminobutyl group, and a triaminobutyl group.
[0068]
23
[0069] Among the cationic functional groups to be introduced into the polymer, an
aminoethyl group is preferable, from the viewpoint of decreasing the cationic functional
group equivalent weight and increasing the cationic functional group density.
[0070] In a case in which the polymer in the invention contains two or more of specific
structural units, the respective structural units may be different from each other in terms of
any of the kind or number of the cationic functional groups contained, the molecular weight,
or the like. The two or more of specific structural units may be incorporated as a block
copolymer, or may be incorporated as a random copolymer.
[0071] Fmther, the polymer may further contain at least one structural unit (hereinafter, may
be referred to as "second structural unit") other than the specific structural unit. In a case in
which the polymer contains a second structural unit, the polymer may be a block copolymer
including the specific structural unit and the second structural unit, or may be a random
copolymer including the specific sttuctural unit and the second structural unit.
The second structural unit is not patticularly limited as far as the second structural
unit is a structural unit derived from a monomer that can undergo polymerization with a
24
monomer that constitutes the specific structural unit. Examples thereof may include a
stmctural unit derived from an olefin, and the like.
[0072] Moreover, in a case in which the polymer in the invention does not have a particular
structural unit but has a random structure formed by branchingly polymerizing a monomer
that constitutes the polymer, the cationic functional group may be contained as at least a part
of the main chain, or may be contained as at least a part of a side chain, or may be contained
as at least a part of the main chain and at least a pati of a side chain.
[0073] The polymer in the invention is also preferably a polymer that has a critical micelle
concentration in an aqueous medium of 1% by mass or more, or a polymer that does not
substantially form a micelle structure. Here, the expression "does not substantially form a
micelle stmcture" refers to that a micelle is not formed under an ordinary condition such as in
an aqueous medium at an ordinary temperature, that is, the critical micelle concentration
cannot be measured. Since the polymer has such a feature, a thin polymer layer having a
thickness of molecular level (for example, 5 mu or less) can be formed more effectively.
[0074] In the invention, the content of the polymer in the composition is not particularly
limited, and the content can be set, for example, from 0.01% by mass to 5.0% by mass, and is
preferably fi·om 0.02% by mass to 0.3% by mass.
[0075] (Method of Producing Polymer)
As the method of producing a polymer having a branching degree of 48% or more,
which is a preferable form of the polymer, for example, a production method including a
process of reacting a raw material polymer containing at least one of a primary nitrogen atom
or a secondary nitrogen atom with a monomer having a cationic functional group is
preferable.
By the above reaction, at least one of a tertiary nitrogen atom or a quaternary
nitrogen atom can be generated from at least one of the primary nitrogen atom or the
secondary nitrogen atom contained in the raw material polymer, and thus, a polymer having a
branching degree of 48% or more can be suitably obtained.
The above reaction can be conducted by mixing the raw material polymer and the
monomer having a cationic functional group in a solvent such as water or an alcohol, and
heating the mixture under reflux.
The reaction time can be adjusted as appropriate and is, for example, preferably from
1 hour to 24 hours, and more preferably from 2 hours to 12 hours.
[0076] The raw material polymer in the method described above is not particularly limited
as far as the raw material polymer contains at least one of a primary nitrogen atom or a
secondary nitrogen atom, and a raw material polymer containing a secondary nitrogen atom is
25
preferable.
Examples of the raw material polymer containing a secondary nitrogen atom include
a polyalkyleneimine that is a polymer of an alkyleneimine having from 2 to 12 carbon atoms
(preferably from 2 to 8 carbon atoms), poly(N-alkylamide), and any derivatives thereof.
Here, specific examples of the alkyleneimine having from 2 to 12 carbon atoms are as
described above. In addition, examples of the derivatives include a polyalkyleneimine, into
which an anionic functional group has been introduced, and the like.
[0077] The weight average molecular weight of the raw material polymer is not pmticularly
limited as far as the weight average molecular weight enables production of the polymer
having a weight average molecular weight of from 2,000 to I ,000,000 by the reaction with a
monomer having a cationic functional group.
For example, the weight average molecular weight ofthe raw material polymer is
preferably from I ,000 to 500,000, more preferably from 2,000 to 200,000, and particularly
preferably from 5,000 to 150,000.
[0078] Examples of the monomer having a cationic functional group, which may be used in
the above production method, include nitrogen-containing compounds.
Futther, it is preferable that the cationic functional group in the monomer having a
cationic functional group, which is used in the above production method, is bonded to a
protective group that is stable under the reaction condition.
By having such a configuration, the reaction between the cationic functional group
monomers can be suppressed, and thus a polymer having a higher branching degree can be
produced.
[0079] As the protective group, a generally used protective group can be used.
Examples of the protective group include a t-butoxycarbonyl group (a Boc group), a
benzyloxycarbonyl group, a methoxycarbonyl group, a fluorenylcarbonyl group, a formyl
group, an acetyl group, a benzoyl group, a phthaloyl group, an allyl group, and a benzyl
group.
[0080] The monomer having a cationic functional group bonded to a protective group is
more preferably a nitrogen-containing compound having a nitrogen atom which is bonded to a
protective group.
Specific examples of the nitrogen-containing compound having a nitrogen atom
which is bonded to a protective group include compounds represented by any one of the
following Formulae (m-1) to (m-3).
[0081]
26
H
R-N"- ~
\....,}_ ~0
n
(m-1)
(m-3)
Br
R-N~ H n
(m-2)
[0082] In Formulae (m-1) to (m-3) above, R represents a protective group, and n represents
an integer from I to 4.
The protective group represented by R may be any functional group that is generally
used as the protective group for a nitrogen atom and, for example, a t-butoxycarbonyl group
(a Boc group), a benzyloxycarbonyl group, a methoxycarbonyl group, a fluorenylcarbonyl
group, a formyl group, an acetyl group, a benzoyl group, a phthaloyl group, an allyl group, or
a benzyl group is preferable.
[0083] The nitrogen-containing compound (monomer) having a nitrogen atom which is
bonded to a protective group is more preferably a compound represented by Formula (m-1)
above, and particularly preferably a compound (protected aziridine) represented by Formula
(m-1) above, in which n represents I.
The method of producing the polymer according to the -invention is particularly
preferably a production method including a process of reacting a raw material polymer
containing a secondary nitrogen atom (for example, a polyalkyleneimine that is a polymer of
an alkyleneimine having from2 to 12 carbon atoms) with a compound represented by
Formula (m-1) above.
[0084] The method of producing a polymer may include other process, such as a process of
deprotecting the cationic functional group having a protective group, which has been
introduced into the polymer, if necessary.
[0085] (Acid)
The composition in the invention preferably contains at least one kind of acid.
This form is suitable in the case of adjusting the pH of the composition in the
invention to the acidic side. The preferable range of the pH of the composition is as
described above.
The acid is not particularly limited, and examples of the acid include a
monocarboxylic acid compound, a dicarboxylic acid compound, and an oxydicarboxylic acid
27
compound.
Examples of the monocarboxylic acid compound include aliphatic monocarboxylic
acid compounds (for example, formic acid, acetic acid, propionic acid, butyric acid,
methoxyacetic acid, ethoxyacetic acid, lactic acid, glycolic acid, glyceric acid, and the like)
and aromatic monocarboxylic acid compounds (for example, benzoic acid, picolinic acid,
salicylic acid, 3,4,5-trihydroxybenzoic acid, and the like).
Among the above compounds, monocarboxylic acid compounds are preferable, and
aliphatic monocarboxylic acid compounds are more preferable, and formic acid and acetic
acid are pmiicularly preferable, from the viewpoint of achieving both the difficulty of
remaining the polymer on the member A and the ease of remaining the polymer on the
member B.
[0086] As the monocarboxylic acid compound, a monocarboxylic acid compound
(hereinafter, may also referred to as "specific monocarboxylic acid compound"), that does not
have a hydroxyl group or an amino group, and that has a van der Waals volume of 40 cm3/mol
or more is also preferable.
Inclusion of a specific monocarboxylic acid compound in the composition is
advantageous in that it becomes hard for the polymer in the composition to adhere to the
surface of the member A, in the application process of applying the composition containing
the polymer to the surface of the member A. The reason for this is not clear, but is guessed
as follows. Namely, a specific monocarboxylic acid compound having a van der Waals
volume of 40 cm3/mol or more includes a bulky hydrophobic group and one carboxyl group.
It is thought t4at, when a composition containing the specific monocarboxylic acid compound
and the polymer is applied to the surface of the member A (for example, copper), the carboxyl
group of the specific monocarboxylic acid compound reacts with the surface of the member A,
and thus the surface of the member A is covered with the bulky hydrophobic group and, as a
result, the surface of the member A is hydrophobilized. Here, it is thought that, since the
hydrophobic group that covers the surface of the member A is bulky, the surface of the
member A is more strongly hydrophobilized (that is, the surface energy is lowered).
Moreover, it is thought that, since the specific monocarboxylic acid does not have a hydroxyl
group or an amino group, the surface of the member A is more hydrophobically maintained.
For these reasons, it is thought that the adhesion of polymer to the surface of the member A is
more effectively inhibited, and thus, the polymer in the composition hardly adheres to the
surface of the member A.
Regarding the case in which the composition contains the specific monocarboxylic
acid compound, for example, when explained using Fig. 1, in this case, it is advantageous in
28
that a polymer layer is hardly formed on the exposed face 20a in the process of applying the
composition to the exposed face 20a.
Accordingly, for example, it is possible to omit the process of removing the polymer
layer on the exposed face 20a. For example, even in a case in which the process of
removing the polymer layer is omitted, a state, in which the polymer layer is formed on the
exposed faces of the respective insulating layers, but the exposed face 20a is not covered with
the polymer layer, can be provided.
[0087] For the numerical value of the van der Waals volume of the specific monocarboxylic
acid compound, the value described in "CHEMICAL PROPERTIES HANDBOOK" (edited
by YAWS, published by McGraw Hill) is used.
It is more preferable that the van der Waals volume of the specific monocarboxylic
acid compound is from 40 cm3 /mol to 85 cm3 /mol.
[0088] As the specific monocarboxylic acid compound (the monocarboxylic acid compound
that does not have either a hydroxyl group or an amino group, and has a van der Waals
volume of 40 cm3/mol or more), specifically, propionic acid, picolinic acid, butyric acid,
valerie acid, hexanoic acid, heptanoic acid, acrylic acid, picolinic acid, and the like are
preferable. Particularly, propionic acid and picolinic acid are preferable.
[0089] Moreover, in a case in which the surface of the member A, to which the composition
is to be applied, is subjected to the pretreatment described above (pretreatment using, for
example, benzotriazole, phenanthroline, bipyridyl, or the like), before the application of the
composition to the surface of the member A, even when the specific monocarboxylic acid
compound is not used but formic acid or acetic acid is used, it is possible to make the polymer
hardly adhere to the surface of the member A in the application process of applying the
composition to the surface of the member A.
[0090] The composition in the invention may further contain a hydrophobilizing agent.
As the hydrophobilizing agent, those commonly used may be used, and a chelating
agent that forms a hydrophobic group on the surface of the member A, such as 8-quinolinol,
benzotriazole, phenanthroline, bipyridyl, 2,2 '-bipyridine, 1, 1 0-phenanthroline, tribipyridine,
acetylacetone, triaminopropane, tribipyridine, or phthalic acid, and the like are preferable.
[0091] It is preferable that a content of sodium and a content of potassium in the
composition in the invention are each 10 ppb by weight or less, on an elemental basis.
Herewith, deterioration in electric propetiies (for example, in a case in which the composite
body includes a transistor, operation failure of transistor or the like), in the case of using an
electronic device as the composite body, can be suppressed.
[0092] A particularly preferable form of the composition in the invention is a form of a
29
composition that contains a polymer having a cationic functional group and having a weight
average molecular weight of from 2,000 to 1,000,000 and a branching degree of 48% or more,
and that has a pH of from 2.0 to 11.0, in which a content of sodium and a content of
potassium in the composition are each 10 ppb by weight or less, on an elemental basis.
In this form, it is more preferable that the composition fmiher contains a
monocarboxylic acid compound.
In this form, a preferable range ofthe pH is as described above.
Fmiher, in the case of using the composition in the invention as a semiconductor
sealing composition, this form is particularly preferable.
[0093] Moreover, the composition in the invention is preferable not only for a
semiconductor sealing composition, but also for a sealing composition in various electronic
devices (a print wiring substrate, a display device, and the like).
[0094] The composition in the invention can contain a solvent, in addition to the polymer, if
necessary.
The solvent is not patiicularly limited as far as the solvent is a solvent that uniformly
dissolves the polymer and hardly forms a micelle. Examples of such a solvent may include
water (preferably, ultrapure water) and water-soluble organic solvents (for example, alcohols
and the like). In the invention, fi·om the viewpoint of micelle forming property, it is
preferable to use water or a mixture of water and a water-soluble organic solvent, as the
solvent. Fmiher, the boiling point of the solvent is not patiicularly limited, but is preferably
210°C or lower and more preferably 160°C or lower. When the boiling point of the solvent
is within the above range, the solvent can be easily removed at a low temperature.
With regard to the components of the composition, the components of a composition
described, for example, in WO 2010/137711 and WO 2012/033172, can be referred to, as
appropriate.
[0095] The composition in the invention preferably has an average particle diameter
measured by a dynamic light scattering method of 150 mn or less.
When the average particle diameter is 150 mn or less, the covering property of the
polymer layer with respect to the member B is further enhanced. For example, even in a
case in which a concave portion, an opening, or the like is formed in the member B, the wall
faces of the concave pmiion, the opening, or the like can be suitably covered with the polymer
layer.
Here, the average particle diameter is measured by a dynamic light scattering method
using an ELSZ-2, manufactured by Otsuka Electronics Co., Ltd., and is obtained as a
cumulant average patiicle diameter. Regarding the measurement conditions, measurement is
30
conducted under the conditions of, for example, a cumulated number of70 times, a repeat
count of3 times, in a solution concentration of from 0.1% to 1.0% and a temperature of from
23°C to 26°C. A stable measurement can be carried out, by adding an electrolyte such as
NaCl, if necessary.
[0096] Note that, the case in which the above average pmiicle diameter in the composition is
more than 150 nm is specifically a case in which a micelle (a micelle having an average
particle diameter of more than 150 nm) is formed in the composition, a case in which
polishing grains of a metal oxide or the like that are used at the time of polishing (chemical
mechanical polishing) the wiring are included in the composition, or the like.
[0097] The above average particle diameter is more preferably 1 00 nm or less, still more
preferably 50 nm or less, yet more preferably 30 nm or less, and patiicularly preferably 10 nm
or less.
[0098]
The application process in the invention is a process of applying the above-described
composition in the invention to the surface (exposed face) of the member A and the surface
(exposed face) of the member B included in the composite member.
[0099] (Method of Applying Composition)
In the application process in the invention, the method of applying the composition is
not particularly limited, and a commonly used method can be used.
Examples of a commonly used method include a dipping method (see, for example,
U.S. Patent No. 5,208,111), a spraying method (see, for example, Schlenoff et al., Langmuir,
16 (26), 9968, 2000 or Izuquierdo et al., Langmuir, 21 (16), 7558, 2005), and a spin coating
method (see, for example, Lee et al., Langmuir, 19 (18), 7592,2003 or J. Polymer Science,
part B, polymer physics, 42, 3654, 2004).
[0 1 00] There is no particular limitation as to the method of applying the composition in
accordance with a spin coating method. For example, a method can be used, in which, while
rotating the substrate equipped with a member A and a member B by using a spin coater, the
composition is added drop wise onto the substrate at the side where the respective members
are formed, then a rinsing liquid such as water is added thereto dropwise, to perform a rinsing
treatment, and then the rotating speed of the substrate is raised to perform drying. In this
process, drying may be carried out after repeating several times the drop wise addition of the
composition and the dropwise addition of water. Further, the following operation may be
performed. Namely, after the dropwise addition of the composition, the rotating speed is
raised to perform drying, and after drying, the resulting substrate is once moved to a heat
treatment equipment such as a hot plate, to perform a heat treatment, and after the heat
31
treatment, the resulting substrate is moved back to the spin coater, followed by performing a
rinsing treatment and drying (the above operation may be repeated several times). The heat
treatment in this case may be a heat treatment (a heat treatment under the condition of a
temperature of from 70°C to 125°C) in the heating process described below.
In the method of applying the composition in accordance with a spin coating method,
there is no limitation on various conditions such as the rotating speed of the substrate, the
amount of the composition added dropwise, the time of adding dropwise the composition, the
rotating speed of the substrate at the time of drying, the amount ofthe rinsing liquid added
drop wise, or the time of adding dropwise the rinsing liquid, and the conditions can be adjusted
as appropriate, while taking into account the thickness of the polymer layer to be formed or
the like.
[0101] In the application process, by applying the composition to the member A and the
member B (and fmiher, if necessary, by appropriately drying the same by a commonly used
method), a layer (polymer layer) that contains the above polymer is formed on the member A
and the member B. After the application of the composition, the polymer may be
crosslinked and polymerized.
The thickness of the polymer layer is not patiicularly limited, and the thickness is, for
example, from 0.3 nm to 5 nm, and preferably from 0.5 nm to 2 nm.
In a case in which the member B includes a porous material, the polymer layer
includes not only a form of a layer that is constituted only of the polymer, but also a form of a
layer (a so-called penetrated layer) that has a configuration in which the polymer is penetrated
into the pores of the porous material.
[01 02]
It is preferable that the manufacturing method of the invention fmiher includes a
heating process of heating the composite member to which the composition has been applied,
under the condition of a temperature of from 70°C to 125°C. Hereinafter, this heating
process may be referred to as "soft bake (process)". Here, the temperature above indicates
the temperature ofthe face of the composite member, to which the composition has been
applied.
By having this heating process, both the difficulty of remaining the polymer on the
member A and the ease of remaining the polymer on the member B can be achieved more
effectively.
Specifically, when the temperature is 70°C or higher, the persistent quality of the
polymer applied to the member B is maintained favorable. Fmiher, when the temperature is
125°C or lower, it is possible to make the polymer more hardly remain on the member A.
32
The temperature is more preferably from 80°C to 120°C, more preferably from 8S°C
to 120°C, still more preferably from 90°C to IIS°C, and pa1iicularly preferably from 90°C to
ll0°C.
[0103] Heating in the present process can be carried out by an ordinary method, and can be
carried out using, for example, an oven or a hot plate.
The atmosphere for carrying out heating in the present process is not pmiicularly
limited and, for exmnple, heating may be carried out under an air atmosphere, or may be
carried out under an in eli gas (nitrogen gas, argon gas, helium gas, or the like) atmosphere.
[0104] The heating time is not particularly limited, but is preferably 300 seconds or less,
more preferably 200 seconds or less, still more preferably 120 seconds or less, and
pmiicularly preferably 80 seconds or less.
The lower limit of the heating time is not particularly limited, but the lower limit can
be, for example, 10 seconds (preferably 20 seconds, and more preferably 30 seconds).
[0 1 OS]
It is preferable that the manufacturing method of the invention further includes a
cleaning process of cleaning the composite member to which the composition has been
applied, with a rinsing liquid at a temperature of from lS°C to 1 00°C.
By having this cleaning process, the removability of the polymer (polymer layer)
from the member A is further improved. The expression "the removability is further
improved" used herein includes that at least a pmi of the polymer can be removed by this
cleaning operation itself, and also that at least a pmi of the polymer is easily removed by other
removal operation (for example, the high temperature heat treatment described below) after
this cleaning operation.
[0106] The rinsing liquid is not particularly limited, but from the viewpoint of improvement
in the cleaning efficiency, it is preferable that the rinsing liquid contains a solvent having high
polarity.
Since the composition contains a polymer having a cationic functional group and has
high polarity, the composition easily dissolves in a solvent having high polarity. Thus, by
using a rinsing liquid containing a solvent having high polarity, the removability of the
polymer fi·om the member A is fmiher improved.
Specifically, it is preferable that the rinsing liquid contains a polar solvent such as
water, methanol, ethanol, propanol, butanol, or propylene glycol monomethyl ether acetate.
Such polar solvents do not significantly damage the interaction between the member
B and the polymer. For this reason, even when cleaning is performed using a rinsing liquid
that contains such a polar solvent, the polymer on the member B (the polymer layer that
33
works effectively) is less likely to be removed, which is thus preferable.
[0107] In the present process, the temperature of the rinsing liquid is from 15°C to 100°C.
This temperature is more preferably from 30°C to I 00°C, still more preferably from 40°C to
1 00°C, and particularly preferably from 50°C to I 00°C.
When the temperature of the rinsing liquid is 15°C or higher (more preferably, 30°C
or higher), the removability of the polymer from the member A is fmiher improved.
When the temperature of the rinsing liquid is I 00°C or lower, evaporation of the
rinsing liquid can be further suppressed.
[0108] Further, the cleaning in the present process may be carried out, while applying
ultrasonic wave to the rinsing liquid.
[0 I 09] From the viewpoint of suppressing the oxidization of the member A, it is also
preferable that the rinsing liquid contains a reducing agent or a compound having a reducing
action. An example of the reducing agent or the compound having a reducing action is
formalin.
[0110] Fmiher, from the viewpoints of preventing cleavage of a carbon-carbon bond and the
like in the polymer of the composition and suppressing the separation of the polymer from the
member B, it is preferable that the content of an oxidative compound (for example, hydrogen
peroxide or nitric acid) in the rinsing liquid is I 0% by mass or lower, and it is more preferable
that the rinsing liquid does not contain an oxidative compound.
[0111] Further, the rinsing liquid preferably has an ionic strength of0.003 or more, and
preferably 0.0 I or more.
When the ionic strength is 0.003 or more, the rinsing liquid dissolves the polymer
more easily, and besides, the rinsing liquid does not significantly damage the interaction
between the member B and the polymer, which is thus preferable.
There is no pat1icular limitation as to the upper limit of the ionic strength, and it is
enough to have an ionic strength of a concentration capable of dissolving an ionic compound.
Note that, the ionic strength is expressed by the following equation.
Ionic strength = 1/2 X E( c X Z2
)
(wherein c represents a molar concentration of the ionic compound included in the
rinsing liquid, and Z represents an ionic valence of the ionic compound included in the rinsing
liquid.)
[0112] In order to adjust the ionic strength, an ionic compound such as an acid described
below or an organic base (ammonia, pyridine, ethylamine, or the like) can be added, if
necessary.
Moreover, a polymer (for example, polyethyleneimine) that catches metal element
34
ions may be added.
[0 113] It is also preferable that the rinsing liquid is a rinsing liquid having a pH at 25°C of 6
or lower (preferably, 5 or lower). By the use of such a rinsing liquid, the removability of the
polymer from the member A is further improved. Moreover, a metal oxide that is formed on
the member A can be dissolved and removed.
In this case, the lower limit of the pH of the rinsing liquid is not particularly limited,
but the pH is preferably 1 or higher, and more preferably 2 or higher.
When the pH is 1 or higher, dissolution of the member B can be further reduced, and
thus, the polymer adhered to the member B can be more suitably maintained.
From the viewpoint of effectively achieving both the removability of the polymer
from the member A and the persistent quality of the polymer applied to the member B, the pH
of the rinsing liquid is preferably from 1 to 6, more preferably from 2 to 5, and patiicularly
preferably from 2 to 4.
[0114] It is also preferable that the rinsing liquid (especially, the rinsing liquid having a pH
at 25°C of 6 or lower) contains at least one kind of acid.
The acid is not pmiicularly limited, but an acid which is less likely to pollute or
destroy the interlayer insulating layer and is less likely to remain on the semiconductor
substrate is preferable. Specific examples of the acid may include monocarboxylic acids
such as formic acid or acetic acid; dicarboxylic acids such as oxalic acid, malonic acid,
succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, fumaric acid, or phthalic
acid; tricarboxylic acids such as trimellitic acid or tricarballylic acid; oxymonocarboxylic
acids such as hydroxybutyric acid, lactic acid, or salicylic acid; oxydicarboxylic acids such as
malic acid or tartaric acid; oxytricarboxylic acids such as citric acid; aminocarboxylic acids
such as aspatiic acid or glutamic acid; organic acids such as para-toluenesulfonic acid or
methanesulfonic acid; and inorganic acids such as hydrochloric acid, nitric acid, or
phosphoric acid.
[0115] Further, as the acid, an acid, which has, in one molecule, at least one (preferably,
both) of a moiety that blocks active species (for example, plasma active species such as
radicals, ions, or electrons) or a functional group that forms a bond with the polymer (the
polymer having a cationic functional group and having a weight average molecular weight of
from 2,000 to 1 ,000,000) when heated, is also preferable. By having such a configuration,
particularly, in the case of performing a plasma treatment (for example, plasma cleaning or
plasma CVD) after the cleaning process, the plasma resistance of the polymer layer formed
from the above polymer can be improved.
In this acid, the number of the functional groups that form a bond with the polymer
35
when heated, in one molecule, is preferably 1 or more, more preferably 2 or more, and
particularly preferably 3 or more.
The moiety that blocks active species is not particularly limited, but specifically, a
functional group having a conjugated system or a metal atom is preferable. Specific
examples thereof include an aromatic group, a manganese atom, and a silicon atom.
In a case in which the polymer layer contains the above-described polyalkyleneimine
(preferably, polyethyleneimine ), an example of the functional group that forms a bond with
the polymer when heated is a carboxyl group. In this case, the carboxyl group reacts with at
least one of the primary amino group or the secondary amino group (imino group) in the
polyalkyleneimine, thereby forming an amide bond or an imide bond.
From the viewpoint of improving the plasma resistance of the polymer layer,
preferable examples of the acid include, specifically, polyvalent carboxylic acids such as
naphthalene tetracarboxylic acid, biphenyl tetracarboxylic acid, benzophenone tetracarboxylic
acid, benzene hexacarboxylic acid, pyromellitic acid, trimellitic acid, ethylenediamine
tetracarboxylic acid, or citric acid, and barbituric acid. Among them, naphthalene
tetracarboxylic acid, biphenyl tetracarboxylic acid, benzophenone tetracarboxylic acid,
benzene hexacarboxylic acid, and pyromellitic acid are preferable.
[0 116] Examples of the plasma include plasma generated from hydrogen gas, helium gas,
argon gas, nitrogen gas, ammonia gas, or the like. There is no particular limitation on the
conditions for generating the plasma, but conditions of such an extent that the polymer layer
formed on the member B is not removed too much are preferred. As examples of such
conditions, conditions of a total pressure of from 20 mTorr to 200 mTorr, a gas flow rate of
from 20 seem to 100 seem, a cathode electrode diameter of fi·om 5 em to 15 em, a discharge
electric power of from 20 W to 200 W, and a treatment time (discharge time) of from 10 sec to
60 sec, may be exemplified.
[0 117] There is no particular limitation as to the amounts of the above-described solvent,
acid, reducing agent, ionic compound, and the like, which may be incorporated in the rinsing
liquid. For example, the above amounts can be adjusted as appropriate such that the pH and
ionic strength of the rinsing liquid each fall within the above preferable ranges, respectively.
[0 118] Further, the rinsing liquid can be prepared by mixing, for example, the
above-described solvent, acid, reducing agent, ionic compound, and the like, but in order to
prevent the electronic circuit and the like from being polluted, it is preferable to prepare the
rinsing liquid under a clean environment such as in a clean room, or to remove the
components, which pollute the electronic circuit and the like, by purification, filtration, or the
like, after the preparation of the rinsing liquid.
36
[0 119] In the present process, the extra polymer layer that is formed on the member A can be
rapidly removed by cleaning (rinsed) with the rinsing liquid, while maintaining the effective
polymer layer that covers that member B. In addition, as described above, an oxide of a
metal element can also be removed and, as a result of which, separation between the member
A and a member (an insulating layer, a wiring, a conductive member, or the like) contacting
the member A, which may be provided as needs arise, can be suppressed.
[0120] Moreover, it is also preferable that the cleaning in the present process is carried out
under a non-oxidizing atmosphere. By carrying out cleaning under a non-oxidizing
atmosphere, it is possible to prevent the member A from being excessively removed, dne to
repeatedly performing the action of removing the metal oxide on the member A, which has
been present before rinsing, with the rinsing liquid, and thereafter dissolving (removing) the
metal oxide, which is produced when the metal element on the surface of the member A is
further oxidized, with the rinsing liquid. For example, a reducing atmosphere gas may be
used, to realize the non-oxidizing atmosphere.
[0121] In the present process, cleaning may be carried out by a commonly used method, and
the method is not patiicularly limited.
The cleaning time is not particularly limited. For example, the cleaning time can be
set from 0.1 minutes to 60 minutes, and is more preferably from 0.1 minutes to 10 minutes.
[0122] In a case in which the manufacturing method of the invention includes the above
heating process (soft bake process) and this cleaning process, regarding the process order, it is
preferable to perform the composition application process, the heating process (soft bake
process), and the cleaning process in this order.
Futiher, the cycle including the above processes in this order may be repeated plural
times.
[0123]
It is preferable that the manufacturing method of the invention futiher includes a high
temperature heating process of heating the composite member to which the composition has
been applied, under the condition of a temperature of from 200°C to 425°C. Hereinafter,
this high temperature heating process may be referred to as "hard bake (process)". Here, the
temperature above indicates the temperature of the face of the composite member, to which
the composition has been applied.
By having this high temperature heating process, the polymer layer formed on the
member A is removed preferentially (preferable, selectively) rather than the polymer formed
on the member B.
[0 124] When the temperature is 200°C or higher, the polymer layer exhibits excellent
37
removability from the composite member.
Further, when the temperature is 425°C or lower, migration of the member A can be
suppressed.
The temperature is preferably from 250°C to 400°C, and more preferably from
300°C to 400°C.
[0125] The pressure (the pressure of an atmosphere, to which the polymer layer is exposed
at the time of heating) when performing heating in the high temperature heating process is not
particularly limited, but the absolute pressure is preferably higher than 17 Pa but lower than or
equal to the atmospheric pressure.
When the absolute pressure is higher than 17 Pa, the speed of removing the polymer
layer is fmiher increased.
When the absolute pressure is lower than or equal to the atmospheric pressure, the
speed of removing the polymer layer is more easily adjusted.
The absolute pressure is more preferably 1,000 Pa or higher but lower than or equal
to the atmospheric pressure, still more preferably 5,000 Pa or higher but lower than or equal
to the atmospheric pressure, and patiicularly preferably 10,000 Pa or higher but lower than or
equal to the atmospheric pressure.
[0126] Heating in the high temperature heating process can be carried out by an ordinary
method using an oven or a hot plate. As the oven, for example, an SPX-1120 manufactured
by APEX Co., Ltd., or a VF-1000LP manufactured by Koyo Thermo Systems Co., Ltd. can be
used.
Further, heating in the present process may be carried out under an air atmosphere,
but from the viewpoints of suppressing oxidation of the member A and the like, heating is
more preferably carried out under an inert gas (nitrogen gas, argon gas, helium gas, or the
like) atmosphere and is patiicularly preferably carried out under a nitrogen gas atmosphere.
[0127] The heating time in the high temperature heating process is not particularly limited,
and is, for example, 1 hour or less, preferably 30 minutes or less, more preferably 10 minutes
or less, and particularly preferably 5 minutes or less. The lower limit of the heating time is
not patiicularly limited, but can be, for example, 0.1 minutes.
When the heating time is 1 hour or less, it is easier to leave the polymer layer on the
member B.
[0 128] In a case in which the manufacturing method of the invention includes the
above-described heating process (soft bake process), the cleaning process, and this high
temperature heating process (hard bake process), regarding the process order, it is preferable
to perform the composition application process, the heating process (soft bake process), the
38
cleaning process, and the high temperature heating process (hard bake process), in this order.
[0129]
The manufacturing method of the invention may further include, as other process,
processes which are performed in the manufacture of electronic devices (for example,
· semiconductor devices), such as a plasma treatment process of performing the plasma
treatment described above, a wiring formation process, or a barrier layer formation process, if
necessary.
[0 130] The wiring formation process can be carried out in accordance with a known method,
such as a metal CVD method, a sputtering method, or an electroplating method.
In a case in which the manufacturing method of the invention has a wiring formation
process, the manufacturing method may fm1her have a barrier layer (copper barrier layer)
formation process, before the wiring formation process. By the formation of a barrier layer,
diffusion of a metal component or a plasma component into the member B can be suppressed
more effectively.
The barrier layer formation process can be carried out in accordance with commonly
used process conditions. A barrier layer formed of a titanium compound (titanium nitride or
the like), a tantalum compound (tantalum nitride or the like), a ruthenium compound, a
manganese compound, a cobalt compound (CoW or the like), a tungsten compound, or the
like can be formed, for example, in accordance with a vapor phase growth method (CVD).
[0 131] Moreover, in a case in which the manufacturing method of the invention has a
cleaning process, the manufacturing method may include a post -rinsing process of fm1her
cleaning the rinsing liquid remaining on the composite body, after the cleaning process.
With regard to the post-rinsing process, description in paragraph 0093 ofWO 2012/033172
can be referred to, as appropriate.
[0132] The method for manufacturing a composite body of the invention as described above
is particularly preferable as the method for manufacturing various electronic devices (a print
wiring substrate, a semiconductor device, a substrate for a display device, or the like) as the
composite body.
An example of the composite body to be manufactured by the method for
manufacturing a composite body of the invention is a composite body, which has a structure
in which an insulating layer that serves as the member B, a polymer layer that contains a
polymer having a cationic functional group and having a weight average molecular weight of
from2,000 to 1,000,000, and a wiring that serves as the member A are disposed in this order,
and in which the thickness of the polymer layer at a pm1 where the wiring does not face the
insulating layer is 5 nm or less (preferably 3 nm or less, more preferably 2 nm or less,
39
particularly preferably I run or less, and most preferably 0 nm (namely, the polymer layer
does not exist)).
In the above example, a second wiring may be formed at a pati where the above
wiring (hereinafter, also referred to as "first wiring") does not face the insulating layer,
whereby the first wiring and the second wiring may be electrically connected. In this case,
since the thickness of the polymer layer between the first wiring and the second wiring is 5
nm or Jess as described above, the two wirings have excellent electrical connectivity.
A semiconductor device which is a fmiher specific example of the composite body
according to the above example is a semiconductor device, which has, on a semiconductor
substrate, an interlayer insulating layer, a first wiring containing copper, a semiconductor
polymer layer that exists between the interlayer insulating layer and the first wiring, and
contains a polymer having a cationic functional group and having a weight average molecular
weight of from 2,000 to 1 ,000,000, and a second wiring that contains copper and is
electrically cmmected to the first wiring, and in which the thickness of the semiconductor
polymer layer in the connecting part between the first wiring and the second wiring is 5 urn or
less.
EXAMPLES
[0133] Hereinafter, the present invention is specifically described with reference to
Examples; however, the present invention is by no means limited to these Examples.
In the following, for "water", ultrapure water (MILLI-Q WATER, manufactured by
Millipore Corporation; resistivity of 18 M.Q·cm (at 25°C) or less) was used.
[0134] [Example lA]
<>
As described below, highly branched polyethyleneimine 1 (a polyethyleneimine that
is highly branched) was synthesized, and subsequently, a composition containing the obtained
highly branched polyethyleneimine 1 was prepared. Details are explained below.
[0135]
(Synthesis of Modified Polyethyleneimine 1)
Modified polyethyleneimine 1 was synthesized according to the following Reaction
Scheme 1, using polyethyleneimine as the statiing material. It should be noted that the
polymer structures in the following Reaction Scheme 1 and Reaction Scheme 2 are structures
that are represented schematically, and the configuration of the tetiiary nitrogen atom and the
secondary nitrogen atom, and the propmiion of the secondary nitrogen atom to be substituted
by a Boc-aminoethyl group as described below may change variously, depending on the
40
synthesis condition.
[0136] -Reaction Scheme 1 -
HN.....-~
y~-/'N~(-/'N~~-/'N~ H H H
Boc: * ~ 0+
[0 13 7] The detailed operation of Reaction Scheme I above is as follows.
61.06 g of polyethyleneimine (SO% aqueous solution) manufactured by MP
Biomedicals Inc. were dissolved in 319 mL of isopropanol, and then 102 g (71 0 mmol) of
N-t-butoxycarbonyl (in Examples, the "t-butoxycarbonyl group" is also referred to as "Boc")
aziridine were added thereto. The resulting mixture was heated under reflux for 3 hours, to
obtain modified po1yethyleneimine 1 having a structure in which a Boc-aminoethy1 group is
introduced into po1yethy1eneimine. It was confirmed, by thin layer chromatography (TLC),
that N-Boc aziridine as the raw material was not present. Then, a small amount of the
product was sampled, and the structure was confirmed by 1H-NMR. From the results of the
1H-NMR analysis, the introduction rate of the Boc-aminoethy1 group with respect to
polyethyleneimine was calculated to be 95%.
- NMR Measurement Results of Modified Polyethyleneimine 1 -
1H-NMR (CD30D); o 3.3-3.0 (br. s, 2), 2.8-2.5 (Br. s, 6.2), 1.45 (s, 9)
41
[0138] (Synthesis of Highly Branched Polyethyleneimine 1)
Highly branched polyethyleneimine 1 was synthesized according to the following
Reaction Scheme 2, using the modified polyethyleneimine 1 as the starting material.
[0139] -Reaction Scheme 2-
Boc-NH
Boc,NH '-------....w---~ HN'Boc
( ( (
'I(N.............-N~N.............-N~N.............-N.....-~
~ ~ ~
B
,..NH B ,...NH B ,...NH
oc oc oc
[0 140] The detailed operation of Reaction Scheme 2 above is as follows.
CH30H
HCI(aq.)
124 mL of 12N hydrochloric acid were slowly added to the isopropanol solution of
modified polyethyleneimine 1. The solution thus obtained was stirred under heating at 50°C
for 4 hours, while being careful about generation of gas. Together with the generation of gas,
a gum-like reaction product was generated in the reaction system. After the completion of
the generation of gas, the reaction system was cooled. After cooling, the solvent that had
been separated from this gum-like reaction product was removed, and then the resulting
reaction product was washed three times with 184 mL of methanol. The reaction product
that had been washed was dissolved in water, and chlorine ions were removed by using an
anion exchange polymer, to obtain an aqueous solution containing 58 g of highly branched
polyethyleneimine I.
- NMR Measurement Results of Highly Branched Polyethyleneimine I -
1H-NMR (D20); 1i 2.8-2.4 (br. m)
42
13C-NMR(D20); o (integration ratio) 57.2 (1.0), 54.1 (0.38), 52.2 (2.26), 51.6 (0.27),
48.5 (0.07), 46.7 (0.37), 40.8 (0.19), 38.8 (1.06).
[0 141] With regard to the highly branched polyethyleneimine 1, the weight average
molecular weight, the molecular weight distribution, the cationic functional group (primary
nitrogen atom, secondary nitrogen atom, tertiary nitrogen atom, and quaternary nitrogen
atom) equivalent weight, the amount(% by mole) of primary nitrogen atom, the amount(%
by mole) of secondary nitrogen atom, the amount (% by mole) of tertiary nitrogen atom, the
amount(% by mole) of quaternary nitrogen atom, and the branching degree(%) were
measured, respectively.
As a result, the weight average molecular weight was 40,575, the molecular weight
distribution was 17.47, the cationic functional group equivalent weight was 43, the amount of
primary nitrogen atom was 46% by mole, the amount of secondary nitrogen atom was 11% by
mole, the amount ofte1iiary nitrogen atom was 43% by mole, the amount of quaternary
nitrogen atom was 0% by mole, and the branching degree was 80%.
[0142] Here, the cationic functional group equivalent weight is a value of the molecular
weight with respect to one cationic functional group, and can be calculated based on the
polymer structure.
Further, the amount(% by mole) of primary nitrogen atom, the amount(% by mole)
of secondary nitrogen atom, the amount(% by mole) oftertiary nitrogen atom, the amount(%
by mole) of quaternary nitrogen atom, and the branching degree (%) were determined as
follows. Namely, the polymer sample (highly branched polyethyleneimine 1) was dissolved
in heavy water, and with regard to the resulting solution, 13C-NMR measurement was
performed at 80°C, using anA VANCE 500 type nuclear magnetic resonance apparatus,
manufactured by Bmker Corporation, in accordance with the single pulse inverse gated
decoupling method. Based on the measurement results, analysis was conducted to determine
what type of amine (nitrogen atom) each of the carbon atom bonds to, and the above amounts
and the branching degree were calculated based on the integrated value thereof. The
assignment is described in European Polymer Journal, vol. 9, page 559, 1973, and the like.
[0143] The weight average molecular weight and the molecular weight distribution were
measured using an analyzer SHOD EX GPC-101 and using a column ASAHIPAK GF-7M HQ,
and calculated using polyethylene glycol as the reference standard. Further, as the eluent, an
aqueous solution having an acetic acid concentration of 0.5 moVL and a sodium nitrate
concentration ofO.l moVL was used. However, as is known in the Mark-Houwink-Sakurada
equation, the calibration curve of GPC changes as the branching degree increases, and thus,
the obtained weight average molecular weight and molecular weight distribution should only
43
be considered as numerical values in terms of polyethylene glycol.
[0144] Here, the amount(% by mole) of primary nitrogen atom, the amount(% by mole) of
secondary nitrogen atom, the amount (% by mole) of tertiary nitrogen atom, and the amount
(%by mole) of quaternary nitrogen atom are amounts represented by the following Equations
A to D, respectively. The branching degree was determined according to the following
Equation E.
Equation A
Amount(% by mole) of primary nitrogen atom= (molar number of primary nitrogen
atom/( molar number of primary nitrogen atom+ molar number of secondary nitrogen atom+
molar number of tertiary nitrogen atom+ molar number of quaternary nitrogen atom)) x 100
EquationB
Amount(% by mole) of secondary nitrogen atom= (molar number of secondary
nitrogen atom/( molar number of primary nitrogen atom+ molar number of secondary
nitrogen atom + molar number of tettiary nitrogen atom + molar number of quaternary
nitrogen atom)) x 100
Equation C
Amount(% by mole) oftettiary nitrogen atom= (molar number of tertiary nitrogen
atom/(molar number of primary nitrogen atom +molar number of secondary nitrogen atom+
molar number oftettiary nitrogen atom+ molar number of quaternary nitrogen atom)) x 100
Equation D
Amount(% by mole) of quaternary nitrogen atom= (molar number of quaternary
nitrogen atom/( molar number of primary nitrogen atom+ molar number of secondary
nitrogen atom + molar number of tertiary nitrogen atom + molar number of quaternary
nitrogen atom)) x 100
Equation E
Branching degree(%)= ((amount(% by mole) of tertiary nitrogen atom+ amount
(%by mole) of quaternary nitrogen atom )I( amount(% by mole) of secondary nitrogen atom+
amount(% by mole) of tertiary nitrogen atom+ amount(% by mole) of quaternary nitrogen
atom) x 100
[0145]
To the aqueous solution of highly branched polyethyleneimine 1 (weight average
molecular weight: 40,575, cationic functional group equivalent weight: 43) obtained as
described above, water and formic acid were added and mixed, to obtain a composition.
In Example lA, the addition amounts of water and formic acid were such amounts
that the concentration of the highly branched polyethyleneimine 1 in the composition became
44
0.25% by mass, and the pH of the composition became 5.0. The "pH" used herein is a value
obtained by measurement with regard to the composition at 25°C (hereinafter, the same
applies.). Here, the pH of the composition was measured as follows. Namely, the
composition was added dropwise onto litmus paper (three kinds of indicators were used;
measurement range: from 2.0 to 9.0) manufactured by MACHEREY-NAGEL, GmbH & Co.
KG, and subsequently, the excess composition was removed. Then, the color was read out
quickly, thereby measuring the pH. Patiicularly, in a case in which plural indicators are
reacted and discolored, the average value is designated as the read out value (pH).
The content of sodium and the content of potassium in the obtained composition
were each measured using an inductively coupled plasma mass spectrometer (ICP-MS) and,
as a result, the contents were both less than or equal to the detection limit(< 1 ppb by mass).
[0146] <>
First, a silicon wafer was prepared, as the member B.
Silica exists on the surface of the silicon wafer.
The isoe1ectric point of this surface is from 1.0 to 3.0 (G. A. Parks, Chemical
Reviews, vol. 65, pages 177 to 198 (1965)).
[0147] The silicon wafer was placed on a spin coater, and 1.0 mL of the composition were
added dropwise for 10 seconds at a constant speed, and the silicon wafer was maintained for
13 seconds. Then, the silicon wafer was rotated at 2,000 rpm for 1 second and at 600 rpm
for 30 seconds, and then futiher rotated at 2,000 rpm for 10 seconds, to perform drying.
In this way, a layer (polymer layer) containing the polymer contained in the
composition was formed on the silicon wafer, thereby obtaining a laminated body (hereinafter
also referred to as "Sample (Si/ PEI)") having a structure in which the silicon wafer and the
polymer layer are layered one on another.
[0148]
The above Sample (Si/ PEI) was placed on a hot plate, and snbjected to soft bake
(heat treatment) at a soft bake temperature of 80°C for 60 seconds, under an air atmosphere.
The "soft bake temperature" used herein is a temperature of the silicon wafer surface.
[0149]
The Sample (Si/ PEI) that had been subjected to the soft bake was rotated at 600 rpm,
using a spin coater, and while rotating, an aqueous solution of pyromellitic acid (pH 4, liquid
temperature 22°C) as the rinsing liquid was added dropwise onto the polymer layer at a
dropwise addition speed of 0.1 mL!sec for 30 seconds, thereby cleaning the polymer layer.
Subsequently, ultrapure water (at a liquid temperature of 22°C) was added dropwise at a
45
dropwise addition speed of 0.1 mL!sec for 30 seconds, then the sample was rotated at 4,000
rpm for 60 seconds to perform drying.
[0150]
With regard to the Sample (Si/ PEl) that had been dried in the cleaning treatment, the
thickness (nm) of the polymer layer on silicon (Si) was measured by an ordinary method
using an ellipsometer of an optical porosimeter (PS-1200, manufactured by SEMILAB CO.,
LTD.).
The measurement results are shown in Table I.
[0151] <>
First, a copper (Cu) substrate as the member A was prepared.
Next, the thickness of the polymer layer on copper (Cu) was measured in a manner
similar to that in the measurement of the thickness of the polymer layer on silicon (Si), except
that, in the above measurement of the thickness of the polymer layer on silicon (Si), the
silicon wafer was changed to the copper (Cu) substrate. Hereinafter, the sample in this
measurement is also referred to as "Sample (Cui PEl)".
The measurement of the thickness of the polymer layer on copper was carried out,
specifically, in a manner as described below.
Namely, the thickness of the polymer layer on an optically flat copper substrate was
calculated by regressing the polarization parameter measured according to ellipsometry in a
multilayer optical model; (air)/ (polymer layer)/ (copper substrate), using WINELLI II. The
range of the light energy used is from 2.2 eV to 5.0 eV. Here, for the refractive index of the
polymer layer, always, the same value as that of silica (Si02) was used. Further, for the
refractive index and extinction coefficient of the copper substrate, the values determined by
using an analysis software WINELLI II, after measuring the polarization parameter of a
copper substrate that does not have thereon a polymer layer, were used.
Note that, a copper oxide layer having a thickness of about 4 nm is present on the
surface of the copper substrate, and this copper oxide layer is removed by reduction after the
hard bake (high temperature heat treatment), and thus, according to the above calculation
method, the thickness of the polymer layer after the hard bake may show a minus value.
Therefore, in the calculation of the thickness of the polymer layer on copper after the hard
bake described below (Examples I C, 3C, and 6C to II C), a copper substrate that does not
have thereon a polymer layer was subjected to hard bake, and the refractive index and
extinction coefficient of the resulting copper substrate after the hard bake were determined
according to the same method as the measurement method above, and depending on these
values, the thickness of the polymer layer on copper after the hard bake was determined
46
according to the same method as the measurement method above.
The measurement results are shown in Table I.
Note that, the isoelectric point of the surface of this copper substrate is from 7.6 to
9.5 (G. A. Parks, Chemical Reviews, vol. 65, pages 177 to 198 (1965)).
That is, the difference between the isoelectric point of the surface of the silicon wafer
and the isoelectric point of the surface of the copper substrate is from 4.6 to 8.5.
When the thickness of the polymer layer on copper (Cu) is less than 75% of the
thickness (nm) of the polymer layer on silicon (Si), the thickness of the polymer layer on Si is
deemed as thick and the thickness of the polymer layer on Cu is deemed as thin.
[0152] [Examples 2A to 4A]
Measurement of the thickness of the polymer layer on silicon (Si) and measurement
of the thickness of the polymer layer on copper (Cu) were carried out in a manner similar to
that in Example 1A, except that the soft bake temperature in Example 1A was changed as
shown in Table 1 below.
The measurement results are shown in Table I.
[0153] [Examples 1B to 4B, and Comparative Examples I to 2]
Measurement of the thickness of the polymer layer on silicon (Si) and measurement
of the thickness of the polymer layer on copper (Cu) were carried out in a matmer similar to
that in Example 3A, except that the pH of the composition in Example 3A was changed as
shown in Table 2 below.
The measurement results are shown in Table 2.
Here, the change in pH in Examples IB to 4B and Comparative Example I was
conducted by changing the addition amount of formic acid. Fmther, the change in pH in
Comparative Example 2 was conducted by the absence of addition of formic acid.
For comparison, the results with regard to Example 3A are also included in Table 2
and Fig. 4.
[0154]
TABLE I
Soft Bake Thickness of Polymer Thickness of Polymer
Temperature (0 C) Layer on Si (run) Layer on Cu (run)
Example !A 80 3.5 1.7
Example2A 90 7.4 2.9
Example 3A 100 8.6 2.4
Example4A 110 8.3 3.5
47
[0155]
TABLE2
pH of Composition Thickness of Polymer Thickness of Polymer
(at 25°C) Layer on Si (nm) Layer on Cu (nm)
Example 1B 4.0 10.6 2.6
Example2B 4.5 9.1 1.8
Example3A 5.0 8.6 2.4
Example 3B 5.5 8.3 4.8
Example4B 6.0 8.9 6.7
Comparative
9.5 8.4 11.0
Example 1
Comparative
10.5 10.4 9.5
Example2
[0156] Fig, 3 is a graph in which the results shown in Table 1 above are plotted, and
specifically, is a graph showing the relationship between the soft bake temperature and, the
thickness of the polymer layer on Si and the thickness of the polymer layer on Cu.
Fig. 4 is a graph in which the results shown in Table 2 above are plotted, and
specifically, is a graph showing the relationship between the pH of the composition and, the
thickness of the polymer layer on Si and the thickness of the polymer layer on Cu.
In Fig. 3 and Fig. 4, "On Si" is a plot showing the thickness of the polymer layer on
Si, and "On Cu" is a plot showing the thickness of the polymer layer on Cu.
[0157] As shown in Table 2 and Fig. 4, it is understood that, in Examples 1B to 4B and 3A,
in which the relationship: the isoelectric point of the surface of the silicon wafer (member B)
>
The Sample (Si/ PEl) of Example 3A above, which had been dried in the cleaning
treatment, was placed in an oven (SPX-1120, manufactured by APEX Co., Ltd.), and the side
of this sample at which the polymer layer (PEl) had been formed was subjected to hard bake
(high temperature heat treatment) at a temperature of 350°C for 2 minutes, in a nitrogen gas
50
(N2) atmosphere under the condition of a pressure of 10,000 Pa. Here, the temperature
above indicates the temperature of the PEl surface of the Sample (Si/ PEl).
[0165]
With regard to the Sample (Si/ PEl) after the hard bake (high temperature heat
treatment), the thickness (nm) of the polymer layer on silicon (Si) was measured by an
ordinary method, using an ellipsometer of an optical porosimeter (PS-1200), manufactured by
SEMlLAB CO., LTD.
The thickness of the polymer layer on silicon (Si) was 4.7 nm, and the thickness (8.6
run) of the polymer layer in the Sample (Si/ PEl) that had been dried in the cleaning treatment
was maintained to a certain extent.
[0166] <>
The "Sample (Cnl PEl)" of Example 3A above, which had been dried in the cleaning
treatment, was subjected to hard bake (high temperature heat treatment) as described above.
With regard to the "Sample (Cui PEl)" after the hard bake (high temperature heat
treatment), the thickness of the polymer layer on copper (Cu) was measured in a manner
similar to that in the measurement of the thickness of the polymer layer on silicon (Si).
The thickness of the polymer layer on copper (Cu) was 0.3 nm, and was further
reduced, as compared with the thickness (2.4 nm) of the polymer layer in the Sample (Cnl
PEl) that had been dried in the cleaning treatment.
[0167] [Examples 6B to 12B]
Preparation of compositions was conducted tlu·ough adding acetic acid, propionic
acid, picolinic acid, or citric acid, instead of adding formic acid in Example lA, to obtain
compositions. The addition amounts of acids were each such an amount that the
concentration of the highly branched polyethyleneimine 1 in the composition became 0.25%
by mass and the pH of the composition became the numerical value described in Table 5.
Subsequently, the soft bake, cleaning treatment, measurement of the thickness of the
polymer layer, and measurement of the thickness of the polymer layer on copper were
conducted in a mam1er similar to that in Example 1 A, except that the soft bake temperature
was changed to 100°C.
The measurement results are shown in Table 5.
[0168]
51
TABLES
pH of Thickness of Thickness of
Added Acid Composition Polymer Layer on Polymer Layer on
(at25°C) Si (1m1) Cu (mn)
Example 6B Acetic acid 4.5 8.4 -3.8
Example 7B Acetic acid 5.5 8.5 -3.9
Example 8B Acetic acid 6.0 8.8 3.8
Example 9B Propionic acid 4.5 6.0 -3.7
Example 1 OB Propionic acid 5.5 8.7 -3.6
Example liB Picolinic acid 6.0 6.8 -3.4
Example 12B Citric acid 4.0 2.8 0.5
[0169] As shown in Table 5, in Examples 6B to 12B, the thickness of the polymer layer on
copper (Cu) was significantly reduced, as compared with the thickness of the polymer layer
on silicon (Si).
Particularly, in Examples 6B, 7B, and 9B to liB, a polymer layer was not observed
on the copper (Cu). Since the copper oxide on the surface of the copper (Cu) that serves as
the substrate was etched by acid, the thickness of the polymer layer on copper (Cu) was a
minus numerical value.
[0 170] [Examples 1 C, and 6C to 11 C]
The samples of Examples IB and 6B to liB, which had been dried in the cleaning
treatment, were each subjected to hard bake (high temperature heat treatment) similar to
Example 3C. Measurement of the thickness of the polymer layer on silicon and
measurement of the thickness of the polymer layer on copper were carried out, similar to
Example 3C.
The measurement results are shown in Table 6.
[0171]
52
I
-----/
~ TABLE6
pH of Thickness of Thickness of
Added Acid Composition Polymer Layer on Polymer Layer on
(at 25°C) Si (nm) Cu (nm)
Example 1C Formic acid 4.0 5.8 0.4
Example 6C Acetic acid 4.5 5.1 0.7
Example7C Acetic acid 5.5 5.0 0.7
Example 8C Acetic acid 6.0 5.3 1.0
Example 9C Propionic acid 4.5 3.5 0.8
Example 10C Propionic acid 5.5 4.4 0.8
Example llC Picolinic acid 6.0 4.1 0.4
[0172] As shown in Table 6, in all the cases of using formic acid, acetic acid, propionic acid,
or picolinic acid, the thickness of the polymer layer on copper (Cu) was 1 run or less, and was
significantly reduced, as compared with the thickness of the polymer layer on silicon (Si).
[0173] [Example 3D and Comparative Example 2D]
Measurement of the thickness of the polymer layer on silicon and measurement of
the thickness of the polymer layer on copper were conducted in a manner similar to that in
Example 3A and Comparative Example 2, except that the substances obtained by treating the
surface of the silicon wafer and the surface of the copper (Cu) substrate with benzotriazole
(BTA) were used. However, in the measurement of the thickness of the polymer layer on
copper, polarization parameters of a copper substrate that does not have thereon a polymer
layer and that had been subjected to BTA treatment were measured, and then the refractive
index and the extinction coefficient were determined by calculation, and these values were
used as the polarization parameters of the copper substrate in a multilayer optical model; (air)/
(polymer layer)/ (copper substrate).
Pretreatment ofthe substrates using benzotriazole was conducted as follows.
A silicon wafer and a copper substrate were armealed in a nitrogen atmosphere at 20
Pa, at a substrate surface temperature of 350°C, for 10 minutes. Thereafter, the resulting
substrates were dipped in a 1 N sulfuric acid aqueous solution for 5 minutes and, after the
dipping, washed with pure water for 5 minutes, and subsequently, dipped in a 0.0046% by
mass aqueous solution ofBTA for 5 minutes, and then washed with pure water for 5 minutes.
The measurement results are shown in Table 7.
[0174]
53
~ /
-----! =;
~/ TABLE?
pRof Thickness of Thickness of
Added Acid Composition Polymer Layer on Polymer Layer on
(at 25°C) Si (run) Cu (mn)
Example 3D Formic acid 5.0 8.5 0.2
Comparative
none 10.5 6.6 9.8
Example2D
(0175] As shown in Table 7, in Example 3D, the thickness of the polymer layer on copper
(Cu) was 0.2 nm. Accordingly, by subjecting the copper (Cu) surface to the BTA treatment,
the amount of the polymer adhered was smaller by about 2 nm in thickness, as compared with
Example 3A (Table 1) that was not subjected to the BET treatment.
In Comparative Example 2D, the thickness of the polymer layer on copper (Cu) was
9.8 nm, and the polymer remained thick.
(0176] [Examples 9E and IOE]
In Examples 9B and 1 OB, samples that had not been subjected to cleaning treatment
were prepared. Namely, after forming the polymer layer on a silicon wafer and on a copper
substrate, respectively, samples that had been subjected to the soft bake were prepared. With
regard to these samples, measurement of the thickness of the polymer layer and measurement
of the thickness of the polymer layer on copper were carried out, similar to Example 1A.
The measurement results are shown in Table 8.
(0177]
TABLES
pRof Thickness of Thickness of
Added Acid Composition Polymer Layer on Polymer Layer on
(at 25°C) Si (nm) Cu (mn)
Example 9E Propionic acid 4.5 3.8 . -2.3
Example IOE Propionic acid 5.5 8.3 -2.1
[0 178] As shown in Table 8, in Examples 9E and I OE, a polymer layer was not observed on
the copper (Cu). Since the copper oxide on the surface of the copper (Cu) that serves as the
substrate was etched by acid, the thickness of the polymer layer on copper (Cu) was a minus
numerical value.
[0179] The disclosures of Japanese Patent Application No. 2013-067452 filed on March 27,
2013 and Japanese Patent Application No. 2013-179751 filed on August 30,2013 are
54
incorporated by reference herein in their entirety.
All publications, patent applications, and technical standards mentioned in this
specification are herein incorporated by reference to the same extent as if such individual
publication, patent application, or technical standard was specifically and individually
indicated to be incorporated by reference.
CLAIMS
1. A method for manufacturing a composite body, the method comprising:
a composition preparation process of preparing a composition that contains a
polymer having a cationic functional group and having a weight average molecular weight of
from 2,000 to 1,000,000, and that has a pH offrom 2.0 to 11.0;
a composite member preparation process of preparing a composite member that
includes a member A and a member B, a surface of the member B having an isoelectric point
that is lower than an isoelectric point of a surface of the member A by 2.0 or more and the
isoelectric point of the member B being from 1.0 to 7.5, and that satisfies a relationship: the
isoelectric point of a surface of the member B