Claims
[Claim 1]
A solid-state imaging device comprising:
a plurality of solid-state imaging elements each
including:
(A) a photoelectric conversion element, and
(B) a polarizing element formed on a light incident side
of the photoelectric conversion element,
wherein the solid-state imaging device includes two or
more kinds of polarizing elements having different
polarization orientations, and
wherein each of the polarizing elements has a stacked
structure in which a stripe-shaped reflecting layer, an
insulating layer formed on the reflecting layer, and a light
absorption layer made up of a plurality of segments formed on
the insulating layer in a separated state are stacked in that
order from the photoelectric conversion element side.
[Claim 2]
The solid-state imaging device according to claim 1,
wherein an extension direction of the stripe-shaped
reflecting layer is identical to a polarization orientation
where light is to be extinct, and
wherein a repetition direction of the stripe-shaped
reflecting layer is identical to a polarization orientation
where light is to be transmitted.
[Claim 3]
125
The solid-state imaging device according to claim 1 or
2,
wherein the length of the reflecting layer in the
extension direction of the stripe - shaped reflecting layer is
smaller than the length of the solid-state imaging element
along the extension direction of the stripe - shaped reflecting
layer.
[Claim 4]
The solid - state imaging device according to any one of
claims 1 to 3,
wherein an on-chip lens is disposed above the
photoelectric conversion element, and
wherein the polarizing element is formed above the
on-chip lens.
[Claim 5]
The solid- state imaging device according to claim 4,
wherein when the distance in an optical axis direction
between the polarizing element and the on-chip lens is D, the
amount of sagging of the on-chip lens is S, a refractive index
of a medium present between the polarizing element and the
on-chip lens is n1, the width of a gap present between adjacent
polarizing elements is 2xR, and the maximum value of an
incidence angle of light into the polarizing element is 8in-max,
the following relation is satisfied.
R> (D+S) xtan [sin -' { sin (bin-max ) /nil]
[Claim 6]
126
The solid-state imaging device according to claim 4 or
5,
wherein a light blocking layer is formed in a region
positioned between adjacent on-chip lenses and in a region
within a plane positioned between the on-chip lens and the
polarizing element.
[Claim 7]
The solid-state imaging device according to any one of
claims 4 to 6,
wherein the planarization layer and an interlayer
insulating layer formed of an inorganic material are formed
between the on-chip lens and the polarizing element in that
order from the on-chip lens side.
[Claim 8]
The solid-state imaging device according to any one of
claims 4 to 7,
wherein a wavelength selecting layer is disposed between
the photoelectric conversion element and the on-chip lens.
[Claim 9]
The solid-state imaging device according to any one of
claims 1 to 3,
wherein an on-chip lens is disposed above the
photoelectric conversion element,, and
wherein the polarizing element is formed between the
photoelectric conversion element and the on-chip lens.
[Claim 10]
127
The solid-state imaging device according to claim 9,
wherein a wavelength selecting layer is disposed between
the on-chip lens and the polarizing element.
[Claim 11]
The solid-state imaging device according to claim 10,
wherein when a fomation pitch of the segments
constituting the light aborption layer in the extension
direction of the stripe-shaped reflecting layer is Pab-1 and
the length of the segment of the light absorption layer in the
extension direction of the stripe-shaped reflecting layer is
Lab, the values Pab-1 and Lab are determined depending on the
wavelength of light passing through the wavelength selecting
layer.
[Claim 12]
The solid-state imaging device according to any one of
claims 1 to 11,
wherein when a formation pitch of the segments of the
light absorption layer in the extension direction of the
stripe-shaped reflecting layer is Pab-1, a formation pitch of
the segments of the light absorption layer in the repetition
direction of the stripe-shaped reflecting layer is Pab-2, the
shortest wavelength of light incident to the polarizing element
is Xmin, a refractive index of a medium through which light
incident to the polarizing element passes is no, and the maximum
value of an incidence angle of light into the polarizing element
is ®in-max, the following relation is satisfied.
128
(Pab- 12+Pab-22) 1/2<[ (min/no) x cos (Oin-max) ]
[Claim 13]
The solid-state imaging device according to any one of
claims 1 to 12,
wherein when a formation pitch of the segments of the
light absorption layer in the extension direction of the
stripe-shaped reflecting layer is Pab-1 and the length thereof
is Lab, the following relation is satisfied.
0. 5<(Lab/ Pab-1) <1
[Claim 14]
The solid-state imaging device according to any one of
claims 1 to 13,
wherein the extension direction of the stripe-shaped
reflecting layer is at an angle of 45° or 135° with respect to
an arrangement direction of a plurality of solid-state imaging
elements.
[Claim 15]
The solid-state imaging device according to any one of
claims 1 to 14,
wherein the reflecting layer is formed of a metallic
material, an alloy material, or a semiconductor material.
[Claim 16]
The solid-state imaging device according to any one of
claims 1 to 15,
wherein the light absorption layer is formed of a
metallic material, an alloy material, or a semiconductor
129
material.
[Claim 17]
The solid-state imaging device according to any one of
claims 1 to 16,
wherein a protective film is formed on the polarizing
element.
[Claim 18]
The solid-state imaging device according to claim 17,
wherein the polarizing element is formed on a base, and
wherein the protective film is not formed on a portion
of the base positioned between the polarizing element and the
polarizing element.
[Claim 19]
An imaging apparatus comprising the solid-state imaging
device according to any one of claims 1 to 18.
[Claim 20]
A method of manufacturing a polarizing element which has
a stacked structure in which a stripe-shaped reflecting layer
formed on a base, an insulating layer formed on the reflecting
layer, and a light absorption layer made up of a plurality of
segments formed on the insulating layer in a separated state
are stacked, and
a formation pitch of the light absorption layer in a
repetition direction of the stripe-shaped reflecting layer is
Pab_2v a width of the light absorption layer is Wab, and the length
of the segment of the light absorption layer in the extension
130
direction of the stripe-shaped reflecting layer is Lab, the
method comprising the steps of:
(a) forming on the base, a reflecting layer-forming layer
which forms the reflecting layer, an insulating layer-forming
layer which forms the insulating layer, and a light absorption
layer-forming layer which forms the light absorption layer;
(b) patterning the light absorption layer-forming layer
to obtain the light absorption layer-forming layer having the
length of Lab;
(C) forming on an entire surface, a resist layer in which
the formation pitch in the repetition direction of the
strip-shaped light absorption layer is 2xPab-2 and the width
is (Pab-2-Wab), and then forming on a side wall of the resist
layer, an etching mask layer of which the thickness on the side
wall of the resist layer is Wab; and
(c) removing the resist layer and then sequentially
etching the light absorption layer-forming layer, the
insulating layer-forming layer, and the reflecting
layer-forming layer using the etching mask layer as an etching
mask .to thereby obtain the polarizing element having the
stacked structure of the reflecting layer, the insulating layer,
and the light absorption layer.
[Claim 21]
The method of manufacturing the polarizing element
according to claim 20, further comprising a step of forming
a protective film on the polarizing element and the base
131
subsequent to the step (c).
[Claim 22]
The method of manufacturing the polarizing element
according to claim 21, further comprising a step of removing
the protective film on the base after forming the protective
film on the polarizing element and the base.
[Claim 23]
A solid-state imaging element comprising:
(A) a photoelectric conversion element; and
(B) a polarizing element formed on a light incident side
of the photoelectric conversion element,
wherein the polarizing element has a stacked structure
in which a stripe-shaped reflecting layer, an insulating layer
formed on the reflecting layer, and a light absorption layer
made up of a plurality of segments formed on the insulating
layer in a separated state are stacked in that order on the
photoelectric conversion element side.
Dated this 09/05/2012
RANJNA MEHTA-DUTT
OF REMFRY & SAGAR
ATTORNEY FOR THE APPLICANTS
132
Abstract
SOLID-STATE IMAGING ELEMENT, SOLID-STATE IMAGING DEVICE,
IMAGING APPARATUS, AND METHOD OF MANUFACTURING POLARIZING
ELEMENT
The present invention relates to a solid-state imaging
element which is able to provide the solid-state imaging
element having a polarizing element having a simple
configuration and structure based on a wire grid polarizer
technique, a solid-state imaging device, an imaging apparatus,
and a method of manufacturing a polarizing element. The
solid-state imaging device includes a plurality of solid-state
imaging elements 41 each including a photoelectric conversion
element 61 and a polarizing element 70 formed on the light
incident side of the photoelectric conversion element 61. The
solid-state imaging device includes two or more kinds of
polarizing elements 70 having different polarization
orientations. Each polarizing element has a stacked structure
in which a stripe-shaped reflecting layer 71, an insulating
layer 72 formed on the reflecting layer 71, and a light
absorption layer 73 made up of a plurality of segments 73'
formed on the insulating layer 72 in a separated state are
stacked in that order from the photoelectric conversion element
side.