Description

Title: semiconductor device and semiconductor device manufacturing method

Technology areas

[0001]

This invention relates to a semiconductor device and semiconductor device manufacturing method.

His innovations.

[0002]

Capable of joining at a relatively low temperature solder alloys used as bonded semiconductor device package structure bonded semiconductor chip on a circuit pattern provided insulation Board in the past, is known, and semiconductor chip and the circuit pattern. As such as solder materials, primarily Tin (Sn) to solder, for example joints, low melting point Tin - Tin (SN-AG) AG system solder alloys, high-reliability - antimony (Sn-Sb) of solder materials used. Describe the status of solder joints after SN-AG system solder alloys and solder joints after Sn-Sb series solder alloy.

[0003]

Solder Sn to the melting point 200 ° C to 300 ° C degree. Solder Sn to solder bonding layer with dispersed grain Sn. If using a solder of SN 100% solder bonding layer in high-temperature and coarsening of the grain Sn, by temperature stress due to line expansion coefficient difference between non-bonded solder bonding layer takes more at the grain boundary of the Crystal grain SN intergranular crack (intergranular cracking) there SN Crystal grains adjacent to grain boundary cracks, causing the Crystal grain boundaries and develop. SN-AG system solder alloys and solder materials, Sn-Sb is known as intergranular crack propagation to prevent the solder alloy.

[0004]

Figure 7 is the illustration shown schematically with conventional SN-AG system solder solder bonding layer. Figure 7 (a) indicates the State of SN-AG system solder alloys solder bonding layer (, SN-AG system solder joint formation and referred to below) of early (pre-heat load due to power-cycle, etc.). SN-AG system solder alloys, with precipitation strengthening type of solder materials. Using conventional SN-AG system solder alloys, as shown in Figure 7 (a) solder joint formation Ag Sn Crystal grain in almost solid aluminium is Sn grain distributed matrix, because the stiff fine granular Ag3Sn compound 122 121 between grain boundary precipitates. Because this reinforces the grain grain Sn 121 together, difficult to transform crystals and solder bonding layers of Sn Crystal grain unit than the intergranular cracking hard and progress.

[0005]

Figure 8 is the illustration shown schematically by conventional Sn-Sb series solder alloy solder bonding layer. By conventional Sn-Sb series solder alloy solder bonding layer (the Sn-Sb of solder joint formation and referred to below) of the initial state is shown Figure 8 (a). Sn-Sb series solder alloy is a solid solution strengthened solders. Solder bonding layer, as shown in Fig. 8 (a) using the conventional Sn-Sb series solder alloy, Sn grain in 131 8. 5% by weight (= 8. 3 percent at) extent SB derivedfrom, increased grain Sn 131 overall.

[0006]

Solid State able to suppress the coarsening of 131 of Sn Crystal grain by grain Sn 131 overall strengthened by Sb doped during semiconductor heating and cooling by heat load by cycle repeatedly. Also, Sb beyond the solubility limit became stiff SnSb compound 132 along with the Sn Sn grain in 131, partially precipitated. This crystal is difficult to transform and cracks (transgranular cracking) progress and.

[0007]

As a solder alloys containing such as Sn, Ag and Sb-30% Ag:1 and Sb:0... Improve thermal fatigue characteristics of joints in the Sn alloy solder compositions containing 5 to 25 percent of one or two, the rest comes from Sn and unavoidable impurities have to as an unavoidable impurity oxygen (O2) concentration to below 5 ppm, and solder the 3 µm average grain size has been proposed (for example, the following patent documents 1. ）。

[0008]

Also as different solder materials, SB 5-%~15 weight %, Ag 2 %~15 weight % the rest except for unavoidable impurities practically from Sn and surface roughness degree solders in the Ra = 10 µm have been proposed (for example, the following patent documents 2. ）。

[0009]

Also composite solder containing powder in solder as different solder materials, solder materials SB fivefold %~15 weight %, Ag 2 quantity %~15 weight % including the solder the rest except the unavoidable impurities practically Sn consisting of has been proposed (for example, the following patent documents 3. ）。

[0010]

Also, different solder materials 25 weight %~40 weight % Ag and 24 solders consisting of weight %~43 weight % of the Sb as an underwriter with Sn alloy solder, its melting temperature to at least 250 ° C or have been proposed (for example, the following patent documents 4. ）。

[0011]

Also, as another solder material mass %, Ag:0... 9 %~10. 0 percent, Al:0. 01 %~0. 50% Sb:0. 04 %~3. 00% including the Al/Sb ratio is 0. Solder joint member with oxide or oxide surface from the rest Sn and unavoidable impurities, relation of 25 or less (without the 0) have been proposed (for example, the following patent documents see 5. ）。

[0012]

In addition, as different solder materials 0 Ag... 05 mass %~2. 0 mass %, copper (Cu) is 1... 0 mass %, Sb 3... 0 mass %, bismuth (Bi) 2... 0 mass %, indium (In) 4... 0 mass %, nickel (Ni) is 0. 0 is 2% less than the Germanium (Ge). 0 is 1% less than the cobalt (Co). 5 mass % or less (However, Cu, Sb, Bi, In, Ni, Ge, and Co is 0% with a mass is not), and the rest comes from the Tin solder alloys has been proposed (for example, the following patent documents see 6. ）。

[0013]

Also mainly using SnSbAgCu systems as different solders, solders, solder composition is 42% < Sb / (Sn+Sb) ≤ 48% by weight, 5% by weight ≤ Ag < 20% by weight, and 3% by weight ≤ Cu < 10% by weight, and 5% by weight ≤ Ag+Cu ≤ solders and at 25% by weight, the rest consisting of other unavoidable impurities have been proposed (for example, the following patent documents see 7. ）。

[0014]

Also, high temperature solder materials of another to solder materials for each Sb 12 mass 16wt mass %, Ag is 0. 01 mass %~2 mass %, Cu is 0. 1 mass %~1. 5 mass % included, in addition to Silicon (Si) is 0. 001 mass %~0. Includes 1 mass % and B is 0. 001 mass %~0. Solder material included 05 mass %, the rest Sn and unavoidable impurities have been proposed (for example, the following patent documents 8. ）。

[0015]

Also as different solder materials, solid-phase SnSbAgCu of temperature of 225 ° C to principal in Ag and Cu alloy composition 10 weight %~35 weight % and Sb / (Sn+Sb) of the weight ratio is 0. 23-0. 38, solder materials has been proposed (for example, the following patent documents refer to 9. ）。

[0016]

In addition, as different solders, SN 88 mass %~98. 5 mass %, In 1 mass %~10 mass %, up 0. 5 mass %~3. 5 mass %, Cu 0 mass %~1 mass % including the solder Sn-In-Ag solder alloy to base, having in a crystallization modifier to suppress the growth of metallic phase in the solder solidifies the dope has been proposed (for example, the following patent documents 10. ）。

[0017]

Also, different solder materials for Ag:2 mass %~3 mass %, Cu:0. 3 mass %~1. 5 mass %, Bi:0. 05 mass %~1. 5 mass %, Sb:0. 2 mass %~1. Contains 5% and is 5% less than the total content of Ag, Cu, Sb, Bi, Sn underwriter and unavoidable impurities in smooth surface after reflow soldering materials have been proposed (for example, the following patent documents 11. ）。 Furthermore, and reflow the joints of solder paste (add flux to solder powder, suitable viscosity to those) layer is formed, the melted solder, solder to make heat put the parts on the way.

[0018]

In addition, different solders as Ag 1 mass %~3 mass %, Cu 0... 5 mass %~1. 0 is 0 mass %, Bi... 5 mass %~3. 0 is 0 mass %, In... 5 mass %~3. 0 is 0 mass %, Ge... 01 mass %~0. 03% or selenium (Se) is 0. 01 mass %~0. 1 mass %, the remainder consisting of Sn solder alloys has been proposed (for example, the following patent documents 12 references. ）。

[0019]

In addition, as different solder alloys 15 Bi... 0 %~30. 0% silver 1... 0 %~3. Includes 0%, and the copper-0 %~2. 0 percent, and Sb and incidental impurity 0 %~4. Contains 0%, Sn is the remaining solder materials has been proposed (for example, the following patent documents 13 references. ）。

[0020]

Also, different solder materials Sn-Sb-Ag-Cu 4 alloys with a Sb 1. 0 of %~3. 0% by weight, is Ag. 0% by weight or more, 2... 0% less than 1 Cu.... And containing at the rate of 0%, the rest comes from Sn solder alloys has been proposed (for example, the following patent documents see 14. ）。

[0021]

In addition, as different solders, SB 3... 0% by weight (excluding the range minimum value of zero), following Silver's 3. Weight less than 5% (excluding the range minimum value of zero), 1 for Ni... 0% by weight below (excluding the range minimum value of zero), phosphorus (P) is 0. Less than 2 weight % (excluding the range minimum value of zero), and the rest presents a solder alloy consisting of Sn and unavoidable impurities (for example, the following patent documents 15 references. ）。

[0022]

In addition, as different solders, SB 2... 5 heavy amount of %~3. 5% by weight, Ag for 1. 0 of %~3. 5% by weight, 1 for Ni... 0% (excluding the range minimum value of zero), and the rest presents a solder alloy consisting of Sn and unavoidable impurities (for example, the following patent documents see 16. ）。

[0023]

Also, different solder materials as one of cored solder wire rod, wire, Privo - n, and the Ag is 0. 5 heavy amount of %~3. 5% by weight, 3's Bi... 0 of %~5. 0%, Cu is 0. 5 heavy amount of %~2. 0%, 0 is the Sb. 5 heavy amount of %~2. 0% by weight, the remainder consisting of Sn solder alloys has been proposed (for example, the following patent documents 17 references. ）。

[0024]

Also, as another solder, 0... Ag more than 8% by weight of less than 5 weight percent and 0. Include Bi and 17% In total between the two in more than 1% by weight, the remainder is 0 Sn and unavoidable impurities and... 1% by weight or more, 10% of SB-doped even solders have been proposed (for example, the following patent documents 18 references. ）。

[0025]

Also as different solders, SN 61 weight %~69 weight % and Sb 8 amount of %~11% and the Ag 23 weight %~28 weight % containing solders have been proposed (for example, the following patent documents see 19. ）。

[0026]

In addition, as different solders, SN 93 weight %~98 weight %, up 1. 5 heavy amount of %~3. 5% by weight, 0 for Cu. 2 of %~2. 0% by weight, and Sb up 0. 2 of %~2. 0% by weight including the 210 °-solder having a melting point 215 ° C have been proposed (for example, the following patent documents refer to the 20th. ）。

[0027]

Also, as another solder SN 90... Weight of %~99. 2% by weight, 0 for Ag. 5 heavy amount of %~3. 5% by weight, 0 for Cu. 1 of %~2. 8%, and 0 for Sb. 2 of %~2. 0% by weight including the 210 °-solder having a melting point of 216 ° C have been proposed (for example, the following patent documents 21 references. ）。

[0028]

Also, Bi and Sn in at least 90% and the effective amount of Ag includes different solder materials, is also proposed as an optional Sb, Sb or Cu solder materials (for example, the following patent documents 22 references. ）。

[0029]

In addition, as different solder materials 0 Sb... 5 heavy amount of %~4. 0%, zinc (Zn) is 0. 5 heavy amount of %~4. 0%, 0 to Ag. 5 heavy amount of %~2. 0% by weight, and Sn to the 90's. 0 of %~98. Solder materials containing 5% by weight have been proposed (for example, the following patent documents 23 references. ）。

[0030]

Also in solder paste solder materials for another as no. 2 metal powder with melting point higher than the No. 1 metal powders and metal powder first and from metal components and the flux composition, including the No. 1 metal chosen from group unit Sn, Cu, Ni, Ag, gold (Au), Sb, Zn, Bi, In, Ge, Co, manganese (Mn), iron (Fe), chromium (Cr), magnesium (Mg), palladium (Pd), Si, strontium (Sr), tellurium (Te), P consisting of or at least one and Alloys containing SN and solder materials has been proposed (for example, the following patent documents 24 references. ）。

Prior art documents

Patent documents

[0031]

Patent literature 1: special opening of the Akira 61-269998 Gazette
Patent literature 2: special square no. 7-284983 bulletin
Patent literature 3: special square no. 8-001372 bulletin
Patent literature: open public no. 2003-290975 report
Patent literature 5: open 2011-005545 issue public report
Patent literature 6: p-Patent No. 4787384 No.
Patent bibliography 7: p-Patent No. 4609296 No.
Patent literature 8: p-Patent No. 4471825 No.
Patent literature 9: Open 2005-340268 of public information
Patent literature 10: advanced table no. 2010-505625 public report
Patent literature 11: open 2002-018590 of public information
Patent documents 12: open 2001-334385 of public information
Patent documents 13: advanced table 2001-520585 of public information
Patent literature 14: special square no. 11-291083 bulletin
Patent literature 15: p-Patent No. 3353662 No.
Patent literature 16: p-Patent No. 3353640 No.
Patent documents 17: p-Patent No. 3673021 No.
Patent literature 18: special square no. 9-070687 bulletin
Patent literature 19: United States Patent No. 4170472 item specifications
Patent literature 20: United States Patent No. 5352407 item specifications
Patent documents 21: United States Patent No. 5405577 item specifications
Patent literature 22: United States Patent No. 5393489 item specifications
Patent literature 23: United States Patent No. 4670217 item specifications
Patent literature 24: international publication No. 2011 / 027659 No.

Summary of the invention

Inventors are trying to solve a problem

[0032]

Semiconductor equipment be a thermal heat cycles, such as changes in ambient temperature (heating and cooling) or heating load during heating and cooling repetition (power cycle). There is, however, historically, semiconductor equipment, heat load due to power cycle these solder bonding layer is degraded. To improve the life of the solder joint formation for solder joint formation of life and the factors that determine the life span of the equipment, is required. Also, semiconductor devices need power cycle reliability of downsizing overall and cooling body for enabling behavior of semiconductor at high temperature heat (for example, more than 175 ° C), and especially in the power semiconductor devices at this temperature. There should be long-life equipment mounted on vehicles and new energy applications of semiconductor equipment. For this reason, and solder with a low melting point and requires soldering materials capable of forming solder bonding layer with high reliability for the power cycle, etc.. Among the characteristics of semiconductor devices, power cycling reliability semiconductors and operate the temperature cycles prescribed load.

[0033]

For example, as noted above conventional SN-AG system solder alloys commonly used Sn3... 5 Ag solders (Sn up 96. 5% by weight and 3 to Ag. Solder materials containing 5% by weight) is the problem of unreliable behavior at high temperature solder with a low melting point (for example, about 220 ° C) where possible, but there is. Also patent literature 1-or increase the material cost increase Ag content of SN-AG system solder bonding layer in 5 (for example Ag content per 1% 20% cost solder is), high melting point (for example Sn10Ag solders (SN 90's. 0% by weight and is 10 AG. Solder contains 0 WT %) of the melting temperature is approx. 300 ° C) would be. For this reason, increasing the Ag content of SN-AG system solder joints in is not feasible.

[0034]

Also, conventional SN-AG system solder joint formation by the thermal load of the power cycle: problems arise. Figure 7 (b) indicates the conventional SN-AG system solder joint formation power cycling reliability tests at (the State affected by the power cycle heat load). As shown in Figure 7 (b) of SN-AG system solder bonding layer depending on the heat load due to power cycle 121 Sn Crystal grain coarsening and the Ag3Sn compound 122. coarsening to size 5 μm diameter. Sn grains adjacent to grain boundary crack 123, no Sn grain by Ag3Sn compound 122 121 between grain boundary strengthening in the grain Sn 121 between grain boundaries cause intergranular crack 123 121 between Crystal grain boundaries and make progress.

[0035]

Also have a problem of high melting point above conventional Sn-Sb series solder alloy, Sb Sn-Sb series solder materials containing content reliability is higher but the Sb content increases. For example, which is generally used as a conventional Sn-Sb series solder Sn13Sb solder (Sn up 87. 0% by weight and 13 with Sb. Solder alloys containing 0% by weight) that is approx. 300 ° C melting point. In addition, Sn-Sb system solder alloys with improved reliability, increase the Sb content merely with 300 ° C melting point when semiconductor equipment around 175 ° C environment, even in reliability depending on the usage of the equipment require.

[0036]

In addition, conventional Sn-Sb series solder joint formation due to thermal loads such as power cycling following problems arise. Figure 8 (b) indicates the status of the traditional Sn-Sb of solder joint formation power cycling reliability tests at. Sn grain if the solder is distorted by stress, as shown in Figure 8 (b) conventional Sn-Sb series solder bonding layer grain grain Sn 131 together not for better, causing intergranular crack 133 grain Sn 131 between Crystal grain boundaries in the adjacent intergranular crack 133 131 between Crystal grain boundaries and develop an issue there.

[0037]

Also, generally, solder paste reflow heat treatment is done in the furnace atmosphere nitrogen (N2) at over 300 ° C heat treatment is difficult in terms of heat-resistant solder paste (paste solder resistance approx. 250 ° C), produced around 300 ° C solder melting point is difficult to use on the process. You may also, at over 300 ° C heat treatment is possible in for solder paste reflow heat treatment furnace for hydrogen (H2), heat treatment temperature of 350 ° C or more semiconductor chip damage caused by. In addition, softening to heat for a long time of about 30 minutes at a temperature of 300 degrees Celsius, as electrode materials, structural materials based on aluminum (Al), copper and lead to life and defects in shape;

[0038]

This invention is intended to provide the mentioned previously due to technical problems to resolve, able to solder with a low melting point, high reliability soldering bonded semiconductor device and semiconductor device manufacturing method.

Means for resolving problems

[0039]

Semiconductor device and resolve the problems described above, to achieve the objective of the present invention takes this invention is joined together by solder bonding layer configuration between a pair of semiconductor devices, has the following features. Wherein solder bonding layers is Tin atoms: antimony atoms = 1 p (0 < p ≤ 0. 1) of containing Tin and antimony in the ratio 1 of Crystal and Tin atoms: AG atoms = 1: q (2 ≤ q ≤ 5) for part 1 ratio with Tin, silver, and, and the Tin atoms: CU atoms = 1: r (0. 4 ≤ r ≤ 4) of having at least one second part containing Tin and copper in a ratio of 2 crystals, and from a. And, said Crystal above average grain size of the 1st Crystal grain size smaller than the average of.

[0040]

The semiconductor equipment this invention was also the invention described wherein solder bonding layer Tin atoms: antimony atoms = 1: s (0... 8 ≤ s ≤ 1. 6) of no. 3 containing Tin and antimony in the ratio with a Crystal to feature.

[0041]

And semiconductor equipment this invention, invention mentioned above wherein 1st Crystal part antimony solid characteristics to be doped tin grain.

[0042]

And semiconductor equipment this invention, invention mentioned above wherein 1st Crystal, SB solid doped tin grain which, said the third 1st Crystal Crystal Division, said Division and the No. 1 by reacting antimony to the Crystal of solid solubility limit has been exceeded and the grain to feature.

[0043]

Also, semiconductor devices this invention invention mentioned above wherein Crystal wherein the 1st Crystal characteristics to have precipitated at grain boundary between.

[0044]

Also, semiconductor devices this invention is invention described above is the average diameter of the above part 1 by 1 μm that characterized.

[0045]

Also equipment this invention is invention described solder bonding layer of melting point 260 ° C or less that characterized.

[0046]

In addition, solder joint formation by the configuration between a pair of bonded semiconductor device manufacturing method and manufacturing method of semiconductor device and resolve the problems described above, to achieve the objective of the present invention this invention takes and has the following features. Do the process on one of the above configuration applying solder paste containing alloy powder containing antimony, and does not contain antimony alloy powder and mixing. To the solidified by heat treatment wherein solder paste, solder bonding layer formed, wherein solder joint formation by joining the above configuration of each process. 1st Crystal this wherein solder joint formation and second of Crystal and from a. One of Crystal's Tin atoms: antimony atoms = 1 p (0 < p ≤ 0. 1) in proportion with Tin and antimony. Mentioned in part 2 of Crystal's Tin Atom AG atoms = 1: q (2 ≤ q ≤ 5) for part 1 ratio with Tin, silver, and, and the Tin atoms: CU atoms = 1: r (0. 4 ≤ r ≤ 4) of having at least one of the second part containing Tin and copper in proportion. Mentioned in part 2 above average grain size of Crystal, 1st Crystal grain size smaller than the average of.

[0047]

Substantially and regularly arranged according to the invention described above, a uniform microstructure, SB solid containning 1 crystals of (Tin grain) and the first consisting of precipitated at grain boundaries between crystals of multiple part 1 (a compound containing Tin and silver), second part (containing Tin and copper compounds), or both, the second consists of Crystal and the solder joint formation, have been strengthened. 1st Crystal, in solid 1st Crystal by antimony doped for the Department as a whole in solid solution strengthening, due to thermal loads such as power cycle first able to suppress a coarsening of the Crystal. Also, 1st Crystal double-crystal grain boundary division between enhanced by 1 hard to transform crystals, crystals. You can suppress growth of grains in a crack and grain boundary cracks of SN - AG system solder joint formation and Tin - antimony system solder joint formation also this.

[0048]

Also, according to the invention described above, 1st Crystal reaction beyond the solubility limit part of the SB 3 1st Crystal by Crystal, that make up the layer of solder joint strain due to stress because, that can be difficult to further deformation of crystalline. You can also, according to the invention described by 1 and 2 crystals, to temperature 300 ° C lower temperature, for example 260 ° C below the melting point of the solder joint formation. This Tin of conventional soldering process at a temperature of 300 ° C or higher is required-you can get the soldering process at temperatures lower than 300 ° C power cycling reliability of the SB series solder joint formation over. You can provide less adversely affected by heat load than conventional semiconductor devices can reduce the thermal load on the equipment because at 300 ° C lower temperature soldering process possible. Up repeatedly by heat and stress that accompanies it as semiconductor equipment required certain characteristics cannot get enough repetition occurs for the intermittent cyclic resistance for semiconductor equipment, power cycle of reliable capacity and is in. By forming solder bonding layer using the mixed paste, mixed with powder containing antimony, according to embodiments first and no. 2 powder that does not contain SB and than to form solder joint formation consisting of one alloy powder homogeneous paste solder bonding layer further 1-3 Crystal Department arranged substantial and regular uniform microstructure can be.

Advantageous effects of invention

[0049]

Benefits can be provided according to the invention to semiconductor device and semiconductor device manufacturing method, to solder with a low melting point and high reliability soldering bonded semiconductor device and semiconductor device manufacturing method do the trick.

A brief description of the drawings

[0050]

[Figure 1] figure 1 is a cutaway showing structure of semiconductor device takes the embodiment.
[Figure 2] figure 2 is a diagram illustrating the structure of soldering joint figure 1 schematically.
[Fig. 3a] Figure 3A is in cross section of solder joint formation take example 1 power cycling reliability test: state diagram.
[Fig. 3] Figure 3 B, in the cross section diagram of solder joint formation example 3 take power cycle reliability testing at State.
[4A] fig. 4A is section indicating the State of comparative example 1 solder joint formation power cycle reliability testing.
[4b] fig. 4B a section indicating the State of comparative example 2 solder joint formation power cycle reliability testing.
[Figure 5] Figure 5 in the characteristic diagram of the Sb content of semiconductor device and power cycling reliability tolerance.
[Fig. 6] Figure 6 a characteristics diagram showing relation of Ag content of semiconductor device and power cycling reliability tolerance.
[Fig. 7] Figure 7 in the illustration shown schematically with conventional SN-AG system solder solder bonding layer.
[Fig. 8] 8 in figure shown schematically by conventional Sn-Sb series solder alloy solder bonding layer.
[Fig. 9] Figure 9 is a diagram illustrating the melting State for uniform paste for forming solder bonding layer in Figure 1 schematic representation of.
[Fig. 10] figure 10 is shown schematically in molten state of the mixed paste for forming solder bonding layer in Figure 1 illustration.
[Figure 11] figure 11 in the cross section diagram of solder joint formation example 4 take power cycle reliability testing at State.
[Fig. 12] figure 12 in cross section of solder joint formation example 5 to power cycle reliability testing: state diagram.
[Figure 13] Figure 13 in the cross section diagram of solder joint formation example 4 take power cycle reliability testing at another State.
[Figure 14] figure 14 in the cross section diagram of solder joint formation example 5 to power cycle reliability testing at another State.
[Fig. 15] figure 15 in the cross section diagram of solder joint formation take example 1 power cycle reliability testing at another State.

For carrying out the invention

[0051]

Embodiment of suitable below refer to the accompanying drawings, this invention semiconductor device and semiconductor device manufacturing method of describing in detail. Skip to description, in the attached drawing and description of the form of the implementation of the following configuration as well as the same sign a duplicate.

[0052]

(Implementation of)
Describe the structure of semiconductor device takes the embodiment. Figure 1 is a cutaway showing structure of semiconductor device takes the embodiment. Embodiment semiconductor apparatus, as shown in Figure 1, insulation Board 2, such as semiconductor chips 1 with ceramic insulation Board (DCB (Direct Copper Bonding) Board) and copper (Cu) base 6 and semiconductor equipment, for example module structure. The omitted is a cooling body, resin case, terminals, bonding wire diagram in Figure 1. Insulation Board 2, circuit pattern consisting of conductors, such as for example a Cu on the front side of the insulating layer 3 (foil) 4, metal foil, behind copper 5 has been installed on the back side.

[0053]

Back of the semiconductor chip 1 circuit pattern (foil) 4 and joined through a solder joint formation 11. Front of CU base 6, behind copper 5 and joined through a solder joint formation 12. Is not shown, back of the Cu-based 6 joined cooling body and through the compound. In addition, external terminal built on the periphery of the Cu-based 6 resin case is glued. Illustration omitted electrode provided on the front of the semiconductor chips 1 and electrically connected by wire, aluminum wire and circuit pattern (foil) 4 illustration omitted.

[0054]

After contacted through the solder paste, etc. coat bonding of materials between solder joint formation 11, coat bonding of materials together by 12 junction approach, for example at a temperature of more than 250 ° C, 350 ° C or less, 0... Preferably more than 5 minutes, less than 30 minutes between about 1 minute more than holds about 5 minutes following the heat treatment. Solidified by cooling in cooling temperature rate of certain solder paste and solder bonding layer. 1 ° C / sec is the rate of this treatment, but there is at least 5 ° C / s preferably lowering rates, more preferred is below 15 ° C, 8 ° C / sec. Lowering temperature speed of heat treatment for forming solder bonding layer in the conventional joining methods was 1 ° C per second, but the configuration of solder bonding layer and you can't solder bonding layer on the cracks are coming, had degraded the power cycle reliability. You can solder bonding layer 11 metal structure allows it to above conditions yield rates in the present invention, shown below, 12. The environment inside the furnace when the don't care either hydrogen or nitrogen atmosphere. Furthermore, wherein the joints, semiconductor chips, semiconductor devices such as circuit pattern (foil) 4, metal foil (insulating Board), heat spreaders (Cu-based) configuration of. Configuration of the joint, the semiconductor chip 1 and circuit pattern (foil) 4, Cu base 6 and back foil 5, lead frame and metal foil (insulating boards), etc.

[0055]

Solder bonding layer 11, 12, for example, using cream solder paste solder materials in place, including in certain proportions of powder and flux (松yani etc.) and mixed form. You may be in the solder paste containing two or more coordinated composition may have moderate viscosity spreads wet on the surface area of the place, and application of welding material on dispenser, you can well, one type of alloy powder containing solder paste (homogeneous paste to) in a different alloy powder (mixed paste to) solder paste for forming solder layer junction 11, 12. Bonding coat bonding of materials together by means of solder paste, for example, applying solder paste coat bonding of materials on one of which the solder joint formation 11, 12. To configure and deploy the cover of joints on the other hand on the solder paste, solidify the solder paste by heat treatment, be solder bonding layer 11, 12, pasted coat bonding of materials between system alignment and integration. You may use the materials commonly used in the semiconductor, contained in the solder paste flux.

[0056]

May be also used the powder was adjusted to the desired composition powders of solder materials contained in the solder paste for forming solder layer junction 11, 12. For example, solder bonding layer 11 and 12 is 89Sn8Sb3Ag (89 with Sn. 0% by weight, 8 with Sb. 0% by weight and 3 to Ag. Contains 0 WT %) fields are formed using a solder alloy, 89 8Sb3Ag Sn alloy powder to use better (i.e. a uniform paste form). Also powder of solder materials contained in the solder paste for forming solder layer junction 11, 12, using a mixture of two or more adjusted to the different composition of alloy powder is better (i.e. mixed paste form). May be mixed in a weight ratio of powder to mix two or more types of alloy powder containing Sb first and no. 2 powder that does not contain Sb and solder paste. Specifically, for example, 81. 5Sn16Sb2. 5-Ag alloys (Sn up 81. 5% by weight, 16 for Sb. 0% by weight and 2 with Ag. Alloys containing 5% by weight) of the powder first, and 96. 5Sn3. 5-Ag alloys (Sn up 96. 5% by weight and 3 to Ag. Alloys containing 5% by weight) of the mixture by weight 1:01 no. 2 powder and the solder paste. To heat the solder paste to 89 can be formed 8Sb3Ag Sn alloy solder joint formation 11, 12.

[0057]

The solder joint formation 11, 12 describe in detail. Figure 2 is a diagram illustrating the structure of soldering joint figure 1 schematically. Fig. 2 (a) indicates the status of solder joint formation 11, 12 early (before the heat load due to power cycle). Solder bonding layer 11 and 12 is formed by the common solder joints using solder contains Tin (Sn), antimony (Sb) and silver (Ag) the prescribed amount. You may solder bonding layer 11, 12 further Cu content in certain proportions. May be in this case, solder bonding layer 11 and 12 is formed using a given amount of solder of Sn, Sb, Ag and Cu, respectively. You can improve the solder wettability of Ag that solder joint formation 11, 12 by.

[0058]

As shown in Figure 2 (a) solder joint formation 11, 12, matrix and dispersed the first 21 each of Crystal grain in the 1st Crystal harder than, 21, and 1st Crystal, 21 more than for more than one second, small and fine grained then columnar grain size (diameter) which precipitated crystals (grains) 22. The first crystals of 21 for Sn atoms more than 0 Sb atoms below the solid-liquid limit, for example Sn atom: Atom = 1: p (0 < p ≤ 0. 1) of Sn grains containing Sn and Sb in the ratio in the first crystals of 21 on solid by Sb doped crystal grains solid solution strengthening is the first Crystal Crystal Department 21 is rigid..

[0059]

Also, 1st Crystal grain boundaries of the 21 other 2 multiple 1st Crystal can have precipitated crystals of 22 enhanced grain of 21 between the crystals are difficult to transform is the. In, said Sn atoms: atoms and the ratio of the number of atoms of the Sn and Sb. The first crystals of 21 average particle size is 0. 2 µm, 100 µm can be in terms of credibility preferred. 1st Crystal this reason, 21 grain size is 0. In May against heat load is close to 2 µm average grain size exceeds 100 m Boyd causes or reliability falls, then turned a non-uniform thermal properties, mechanical properties, etc.. Also, 1st Crystal Crystal if the average diameter of 21 of grain size in the range above, 1st Crystal 22 from easy to form at the grain boundary of the 21 other.

[0060]

2 Crystal, 22, for example, Sn atom: Atom = 1: q (2 ≤ q ≤ 5) in ratio with Sn and Ag and no. 1 metal intermetallic compound (part 1) 22-1. Multiple No. 1 metal between the compounds 22-1 of the most No. 1 metal between compounds 22-1 of the average particle size is 10 μm can be less than desirable, even 0. 1. 1 m or more. Can be 0 m less than in terms of credibility preferred. So many included having a particle size of 1 μm or less 1 metal between the compounds 22-1 solder joint formation 11, 12, 1st Crystal grain of 21 other strengthening mechanisms to improve good. 2 Ag content of crystals in the 22 is changing due to presence of antimony solder materials in content and the solder joints when other atoms. No. 1 metal between the compounds 22-1 and Sn-Ag be Ag3Sn (Sn atom: Atom = 1:03) compounds and Ag4Sn (Sn atom: Atom = 1:04), compounds etc.

[0061]

2 1st Crystal crystals of 22 and exist at the grain boundary of the 21 other no. 1 Crystal crystals of 21 other has partial bound over, 22. In addition, 1st Crystal part of 21 other directly without interface is nice exists. Also, Crystal, 22, of joints and 1st Crystal other 2 different well, composition is formed between the 21st of crystals of 22 and 1 may be formed between the crystals of the 21. Crystal, 22, later third Crystal 23 between the third crystals of 23 and 1 between crystals, 21, or the third may be formed between the crystals of 23 and the joints. Crystal, 1st Crystal can be formed of 22 at the grain boundary of the 21 crack lesser will be. 1st Crystal this means enhanced grain, 21.

[0062]

1 the percentage of crystals of the 21 area No. 1 metal between the compounds 22-1 in area (No. 1 metal compounds 22-1 of area ratio S1 to) for example is greater than 0%, 5% or less good (0% < S1 ≤ 5%). Benefit to avoid intergranular crack propagation by S1 No. 1 metal compounds 22-1 of area ratio to greater than 0%. Preferably no. 1 metal compounds 22-1 of area ratio s1 for example is in at least 2%, 5% or less good (2% ≤ S1 ≤ 5%). The reason is as follows. No. 1 metal compounds 22-1 by S1 No. 1 metal compounds 22-1 of area ratio to 2% over the 1st Crystal which can enhance the effect to avoid intergranular crack propagation could almost completely cover the part 21. Also, in S1 No. 1 metal compounds 22-1 of area ratio greater than 5%, 1 metal between compounds 22-1 (for example Ag3-Sn compound) of the particle size increases to avoid intergranular crack propagation effect decreases. Area ratio and average grain size can be to determine the No. 1 metal compounds 22-1 of 1 μm diameter, for example 1st Crystal from the 1500 x magnification SEM (Scanning Electron Microscope) image, 21 diameter more than 10 large areas, e.g. 30 μm x 30 µm was calculated by image processing in. Specifically and clearly outline of the particle using image processing and authorizing certain particles. Seeking size and particle size the particles in a circle or a polygon, etc..

[0063]

In addition, Crystal, 22, for example, Sn atom:Cu Atom = 1: r (0. 4 ≤ r ≤ 4) of may be in proportion with Sn and Cu and no. 2 intermetallic compounds (part 2) 22-2. Also, no. 2 Crystal May 22 was configured with 2 metal between the compounds 22-2 and no. 1 metal compounds 22-1. No. 2 metal between the compounds 22-2 and Cu6Sn5's (Sn atom:Cu Atom = 5:06) Sn compound, Cu3(Sn atom:Cu Atom = 1:03) compounds, etc. 2 Cu crystals, 223Sn compound Sn is Cu from material Cu (circuit pattern 4 and back foil 5) molten solder bonding layer 11, 12 (No. 1 Crystal, 21,) and is formed by reacting. CU3Sn compound, for example at a temperature of more than 250 ° C, 350 ° c, 0... Five minutes more than 30 minutes, preferably 1 minute more than is generated by the heat with a reaction time of about 5 minutes less, located near the Cu material of solder joint formation 11, 12. 3Cu-Sn intermetallic compound produced when heat, lowering temperatures speed preferably 5 ° C per second or more, preferably less than 15 ° C, 8 ° C / sec.

[0064]

Formed by power cycle heat load (during one cycle of temperature changes up to 175 ° C from the temperature (e.g. 25 ° C)) by diffusion of Cu Cu material near solder joints tier 11, 12 in the entire Cu3Sn compounds; In addition, 2 metal between the compounds 22-2, cycle as well as in the power cycle of temperature changes from room temperature to a temperature in the range of 150 ° C to 250 ° C or less heat load generated. The reason for this is inferred as following. On / off for the semiconductor lowering temperature speed is within the range of 5 ° C per second or more, less than 10 ° C / second is. Crystal and holding temperature power cycle test and the rapid cooling from this condition is thought to be due to be suitable in the second part, 22 2 metal between compounds 22-2 (Cu-Sn compound) of generation.

[0065]

As the No. 2 metal compounds 22-2 generated the first 1st Crystal for Crystal, 21 in Tin consumption, increases the concentration of 21 in Sb. 1st Crystal this Department 21 is improved than soldering unit Chapter 3 below further produced crystals of the 23 new (third increasing the number if you already have Crystal 23) reliability improvement effect. Effects using by using other material form as a material of joint surfaces are joined together by solder bonding layer 11, 12 other Cu compounds and nickel (Ni), gold (Au), Ag, Sn, Cu, as are obtained. And no. 2 metal compounds 22-2 of the average particle size is 10 μm or less preferably, even 0. 1. 1 m or more. Can be 0 m less than in terms of credibility preferred.

[0066]

For this reason, also be generated by prior heat treatment before actually used in solder joint formation 11, 12 solder joints after no. 2 metal compounds 22-2 preferred. This heat when heat load is in 1 cycles at room temperature and then changing to a temperature in the range of 150 ° C to 250 ° C or less seconds to a few minutes between each repeat once more. Also, this heat is something to hold a few minutes at a temperature in the range of 150 ° C to 250 ° C or less may be. Also, the cooling temperature rate of this treatment is at least 5 ° C / s preferably, preferably with at least 8 ° C per second, less than 15 ° C per. Due to heat stress in other members and between the members when lowering temperature rate of this treatment to at least 15 ° C / s, not desirable. May be to rapid processing used refrigerant cooled further.

[0067]

The first ratio of the area of Crystal, 21 2 metal between compounds 22-2 of area (No. 2 metal compounds 22-2 of area ratio S2 to), for example good is greater than 0%, 50% or less (0% < S2 ≤ 50%). The reason is as follows. That can enhance a no. 2 metal compounds 22-2 of area ratio S2 is large enough to avoid intergranular crack propagation. Also, by deteriorated solder to be difficult through the molten solder joints at soldering in S2 No. 2 metal compounds 22-2 of area ratio is greater than 50%, 2 metal between the compounds 22 - second barrier and thus void (bubble). Therefore, 1st Crystal part 21 and part 2 and crystal of 22 area ratio is greater than 2%, 55% or less preferred.

[0068]

Also, 1st Crystal solder bonding layer 11, 12, 21 and 1 reacts with Sb beyond the solubility limit to the Crystal, 21, will be the third Crystal, 23, may have. 3 Crystal, 23, for example, the Sn atom: Atom = 1: s (0... 8 ≤ s ≤ 1. 6) of grain ratio with Sn and Sb in. No. 3 Crystal, 23 is the SnSb (Sn atom: Atom = 1:01) Sn compounds and Sb23(Sn atom: Atom = 3:02) intermetallic compounds and other compounds in the first harder than Crystal, 21. Sb for SN grain (volume saturated) solid solubility limit varies by the existence of other atoms solder joints at the solder joints during heat treatment temperature and cooling temperatures, solder in the Sb content, etc.. The No. 3 Crystal 23 average particle size is 0. 1 µm, 100 µm in terms of credibility preferred. This is the first attributed to the Crystal, 21, for the same reason. Also, no. 3 Crystal No. 3 crystals larger than 100 μm particle diameter of 23 m, unfavorable for solderability degradation to be difficult through the voids in solder and molten solder joint at failure and 23.

[0069]

First third for crystals of the 21 area area of the Crystal, 23 percent (below no. 3 Crystal to area ratio S3, 23), e.g. greater than 0%, 15% or less good (0% < S3 ≤ 15%). The reason is as follows. Chapter 3 which can enhance the larger crystals of 23 area ratio S3 to avoid intergranular crack propagation. Also, no. 3 Crystal 23 area ratio S3 is greater than 15% if the No. 3 Crystal solderability degradation to be difficult through the voids in solder and molten solder joint at failure and 23 from. The first real Crystal, 21, no. 2 Crystal, 22, and the third revealed a good composition, Crystal, 23, in more than one section was composition analysis by EDX (Energy Dispersive X-ray spectrometry) and AES (Auger Electron Spectroscopy), etc..

[0070]

Figure 2 (b) indicates the power cycle reliability testing when this solder bonding layer 11, 12 (the State affected by the power cycle heat load). Power cycling reliability tests are one more fever temperature from room temperature to + 175 ° C changing conditions is the current ON time 0. 5 seconds to 3 seconds OFF time 0. 5 sec to add to 20 second repeatedly energized (test duration: 50 hours). Put Sb doped solid, as the 1st Crystal 1st Crystal also received a power cycle heat load of 21 overall solid solution strengthening for the coarsening of section 21 is not. Therefore, the Crystal No. 1 with 22 21 each of Crystal grain boundary precipitation strengthening mechanism is broken. Shown in Figure 2 (b), as the first one first encounter crack 24 also occurs in crystals of 21 intergranular crack or grains in the crack (crack 24 a) and crystals of 21 consecutive No. 1 Crystal, 21, and the first can be reduced to 21 each of Crystal grain boundary crack 24 it can.

[0071]

Melting mechanism of solder paste to form solder bonding layer 11, 12 explain, first of all, the melting mechanism of homogeneous paste. Figure 9 is a diagram illustrating the melting State for uniform paste for forming solder bonding layer in Figure 1 schematically. Figure 9 (a) shows a uniform paste heat treatment before the heat treatment condition of homogeneous paste in Figure 9 (b). As shown in Figure 9 (a), uniform paste before heat treatment is a 92Sn8Sb grain was distributed for example, matrix (Sn up 92. 0% by weight and 8 with Sb. Grain contains 0 WT %) with 61 between Crystal grain boundaries in 92Sn8Sb Crystal grain 61 more than established, small and fine grained then columnar grain size (diameter) of multiple Ag3Sn compound 62. Configuration consisting of 92Sn8Sb Crystal grain 61 described above for homogeneous paste consisting of only one type of alloy powders and Ag3Sn compound 62 are uniform across homogeneous paste.

[0072]

Into a uniform paste when you heat to form solder bonding layer 11, 12, shown in Figure 9 (b) temperature of the heat treatment, as for example (221 + α) Ag3does not contain parts low Sb degrees Celsius temperature is reached, i.e. melting high Sb Sn compound 62 melted away. Even faster than 92Sn8Sb Crystal grain 61 melted because it exists partially distributed across homogeneous paste with AG3Sn compound 62 Ag3Sn compound 62 similar is apparent across homogeneous paste melting point and melting point of 92Sn8Sb Crystal size 61. Therefore, when a homogeneous paste, heat treatment temperature reaches melting temperature of Ag3Sn compound 62, 62 Ag3Sn intermetallic compound is melted and then reached the melting point of 92Sn8Sb Crystal grain 61 be liquefied whole. Into a uniform paste, preferably set the treatment time to wet uniform paste spread in that longer treatment time may occur if shorter treatment time is void, the void does not occur. For example, if heat over 270 seconds at 260 ° C (the temperature of the semiconductor chip mounted heating plate to 235 ° C) and then nitrogen atmosphere furnace temperature, using a homogeneous paste solder bonding layer 11, 12 Boyd almost does not cause is confirmed.

[0073]

The mixed paste melting mechanism described below. Figure 10 is a diagram illustrating the State of melt mixing paste for forming solder bonding layer in Figure 1 schematically. In Figure 10 (a) in Figure 10 (b) indicates the State of the mixed paste treatment time and before the heat of the mixed paste. Shown in Figure 10 (a) to the mixed paste as no. 1 powder 70-1 and the second contained in isolation in a weight ratio of 70-2 powder. 1 powder 70-1 powder contains the Sb in, for example SB-containning Sn Crystal grain 71-1 distributed matrix structure. Code 71-2 beyond the solubility limit Sb Sn Crystal particulate SnSb compounds deposited along with the Sn in the 71-1. 2 powder 70-2 in powder that does not contain Sb and Sn Crystal particles dispersed in a matrix for example has established multiple Ag3, small and fine grained then columnar grain Sn compound 72-2 Sn Crystal grain 72-1 more than 72-1 between Crystal grain boundaries in configuration.

[0074]

Mixing paste 2 does not contain the high reached when heat treatment for forming solder layer junction 11, 12, as shown in Figure 10 (b), heat treatment temperature for example 221 ° C degree temperature low Sb parts, i.e. melting point Sb 70-2 powder and melted away and that is liquefied. Namely, the No. 2 powder State and was part of the mixed paste is liquefied and liquefied by the end of 70-2 overall. In addition, melted away the second powder 70-2 No. 1 flour (not shown) spread during the 70-1 at the end of the mixed paste is liquefied in a short period of time than a homogeneous paste. In this way does not contain Sb low melting point No. 2 powder 70-2 by the apparent mixed paste melting point decreases. You can also suppress Boyd than to improve the wettability can be liquefied in a short period of time than when using a homogeneous paste in mixing paste, using a uniform paste. For example, furnace temperature to 260 ° C (the temperature of the semiconductor chip mounted heating plate to 235 ° C) was about 110 seconds of heat treatment in nitrogen atmosphere, using a uniform paste solder bonding layer 11, 12 solder bonding layer 11 using the mixed paste is almost entire occurs void, the void fails almost 12 has been confirmed.

[0075]

Verified by power cycling reliability tests mentioned solder bonding layer 11, 12. Describe the first, using a uniform paste solder bonding layer 11 and 12 when power cycling reliability test results. For example, 89Sn8Sb3Ag solders (Sn up 89. 0% by weight, 8 with Sb. 0% by weight, and 3 to Ag. Solders including the 0% weight: approximately 253 ° C melting point) from a uniform paste (i.e. 89 uniform paste containing Sn 8Sb3Ag alloy powder,, uniform paste solders from the) solder junctions formed solder bonding layer 11 thickness 100 µm, 12, watching the State of power cycling reliability of solder joint formation 11, 12. As a result (examples 1 to) show in Figure 3A. Furthermore, the temperature of the heat treatment of example 1 in 270 ° C holding time is 5 minutes, lowering temperatures speed was 10 ° C per second and. In addition, 84Sn13Sb3Ag solders (Sn up 84. 0% by weight, 13 with Sb. 0% by weight, and 3 to Ag. Solders including the 0% weight: approx. 290 ° C melting point) from a and solder bonding layer 11, 12 are formed using a uniform paste solder, observed the State of power cycling reliability of solder joint formation 11, 12. This results show (example 3 a) fig. 3. Heat treatment of example 3 at 320 ° C, holding time is 5 minutes, lowering temperatures speed was 10 ° C per second and. Comparative example 1 for traditional 87Sn13Sb solders (Sn up 87. 0% by weight and 13 with Sb. Solders including the 0% weight: approximately 300 ° C melting point) from the solder joints using a uniform paste formed solder joint formation and the observed State of the solder joint formation power cycling reliability tests. Figure 4A shows this result. 320 ° C, the temperature of the heat treatment of the comparative example 1 the retention time is 5 minutes, lowering temperatures speed was 10 ° C per second and. Fig. 3A is a cross section of solder joint formation take example 1 power cycling reliability test: status. Fig. 3 is a cross section diagram of solder joint formation example 3 take power cycle reliability testing at State. Figure 4A is section indicating the State of comparative example 1 solder joint formation power cycle reliability testing. Fig. 3a, 3B, 4A is observed from the semiconductor chip hospitality side SEM image (Figure 4B, 11, 12).

[0076]

Shown in Figure 3A as example 1 solder bonding layers 30-1, SB solid multiple Sn Crystal grain 31 containning is distributed as a matrix, and Sn Crystal grain 31 (1 crystals of) at the grain boundary between Sn Crystal grain 31 (average particle size approx. 30 µm) enclose the as 0. Fine granules with a diameter of 5 μm or less stiff Ag3Sn compound 32-1 (second Crystal part No. 1 metal intermetallic compounds) can be deposited. Also reacts with the Sb one Sn Crystal grain 31 exceeds the solubility limit SnSb compound 33 (3 crystals of) the also junction near solder joints tier 30-1 and Cu Member 30-2 Cu6Sn5 compound 32-2 (second Crystal Department no. 2 metal intermetallic compounds) confirmed that. It's solder joints at (at 270 ° C for temperature and heat for about 5 minutes) to formed in the Crystal in the part No. 1 metal intermetallic compounds with 2 metal intermetallic compounds one to multiple first formed around the Crystal,. Also, no. 2 Crystal formed by going through a power cycle heat load (during one cycle of temperature from room temperature change up to 175 ° C) is part of the Department. And even after a power cycle heat load without coarsening 31 Sn Crystal grain diameter and Sn grain Sn Ag3Sn compound 32-1, Cu65 compound 32-2 and SnSb compounds 33 31 between grain boundary precipitation strengthening mechanism, its structure and crack can not be confirmed. The No. 2 crystals occur as well in the power cycle of temperature changes from room temperature to a temperature in the range of 150 ° C to 250 ° C or less heat load of no. 2 intermetallic compounds, one cycle. In addition, confirmed that Sn Sn Crystal grain 31, Ag3compound 32-1 and SnSb compounds 33, as shown in Figure 3 B in example 3, example 1, as well as. On the other hand, in the comparative example 1 solder joint formation 40 Crystal confirmed that distort the solder by thermal stress there is no part for the cause cracked 44 grain Sn 41 between grain boundary (fig. 4A).

[0077]

Describe the power cycling reliability test results when using the mixed paste forms solder bonding layer 11, 12. Watching the State of power cycling reliability of solder joint formation 11, 12, formed by using mixed paste solder solder bonding layer 11, 12. This results (below the examples 4, 5) shown in Figure 11, 12. Figure 11 is a cross section of solder joint formation example 4 take power cycle reliability testing at State. Figure 12 is a cross section of solder joint formation example 5 to power cycle reliability testing: state diagram. Show fig. 11, 12, respectively, annealing temperature to 260 ° C, was for 300 seconds (5 minutes) about heat treatment in nitrogen atmosphere for example 4, 5. Also, heat treatment temperature 230 ° C (up to 232 ° C) nitrogen atmosphere in 300 seconds (5 minutes) degree heat for example 4, 5 shown Fig. 13, 14. Note that lowering temperature speed is made at 10 ° C / sec. Figure 13 is a cross section of solder joint formation example 4 take power cycle reliability testing at another State. Figure 14 in the cross section diagram of solder joint formation example 5 to power cycle reliability testing at another State.

[0078]

Example 4 is a 70Sn30Sb alloys (SN 70's. 0% by weight and 30 SB. Alloys containing 0% by weight) of powder first and 96Sn4Ag alloys (Sn up 96. 0% by weight and 4 for Ag. Alloys containing 0% by weight) of solder joints using mixed paste will be the No. 2 powder mixed with solder bonding layer formation. In example 4, the weight ratio of the No. 1 and no. 2 powders and 1:02... 8 in. Example 5 is the 70Sn30Sb alloys (SN 70's. 0% by weight and 30 SB. Alloys containing 0% by weight) of powder first and 96Sn4Ag alloys (Sn up 96. 0% by weight and 4 for Ag. Alloys containing 0% by weight) of solder joints using mixed paste will be the No. 2 powder mixed with solder bonding layer formation. The weight ratio of the No. 1 and no. 2 powders and 1:01 in example 5. Also, no. 3 crystals by X-ray photoelectron spectroscopy (XPS:X-ray Photoelectron Spectroscopy) in example 4, 5, like example 1, found that Department (SnSb compounds) have been formed. Fig. 11, 12, 1 and 3 crystals of a show on codes 81. Also example 1 as a comparison, annealing temperature at 230 ° C (up to 232 ° C) and the nitrogen atmosphere for 300 seconds (5 minutes) about heat when shown in Figure 15. Figure 15 in the cross section diagram of solder joint formation take example 1 power cycle reliability testing at another State.

[0079]

Similar to example 1 of solder joint with example 4 figure 11, 12 the results using the mixed paste solder, uniform paste consisting of 89Sn8Sb3Ag solder alloy, 5 in (Figure 3A), first of Crystal (third containing crystals of) 81 and the second confirmed the formation of crystals of 82. Namely, solder bonding layer 11, 12, 1st Crystal, as well as cases fabricated solder bonding layer 11, 12 mixed paste, using a uniform paste solder bonding layer 11, 12 when, (third containing crystals of) 81 and the second confirmed can be uniform microstructure substantially and regularly arranged crystals of 82. Also, in example 4, 5, than example 1 1st crystal of (third containing crystals of) 81 and the second was found and both refinement in addition to Crystal, 82, a homogeneous microstructure that can. Namely, using a uniform paste by using the mixed paste more than no. 3 Crystal can suppress that no. 1, 3 crystal growth and aggregation of. The reason is as follows.

[0080]

Example 4 using the mixed paste as shown in Fig. 13, 14, 5, and melts at about 230 ° C is confirmed. It does not melt to semiconductor chip mounted in example 1, as shown in Figure 15, using a uniform paste heating plate temperature is 230 ° C was confirmed. Also to semiconductor chips mounted in example 1 illustrated short, uniform paste using the heating plate temperature is around 260 ° C voids may occur, even without melting completely proved. Than using the mixed paste example 4, example 1 using a uniform paste may be melted in a short time and melt away no. 2 powder that does not contain in the mixed paste of SB Sb first is guessed from the powder while expanding. And in examples 4 and 5 in this way, liquefy the mixed paste advances in a short period of time in Chapter 1 of Crystal (third containing crystals of) 81 and the second speculated further miniaturization of the Crystal, 82.

[0081]

To explain the Sb content of solder joint formation 11, 12. Figure 5 in the characteristic diagram of the Sb content of semiconductor device and power cycling reliability tolerance. SN (100-x-y) by WT %, Sb x % by weight Ag, including, and y % by weight (100-x-y) SnxSbyAg solder alloy solder bonding layer 11, 12 the above example 1 (solder joint formation of homogeneous paste consisting of 89Sn8Sb3Ag solder alloy) and comparative example 1 above for other (solder joint formation of homogeneous paste consisting of 87Sn13Sb solder alloy) and the above example 3 (solder joint formation of homogeneous paste consisting of 84Sn13Sb3Ag solder alloy), Figure 5 shows the measured power cycling reliability ruggedness and prepared the comparative example 2 and example 2. Comparative example 2 is the 97Sn3Ag solder (Sn up 97. 0% by weight and 3 to Ag. Solder contains 0 WT %) from a formed by using a uniform paste solder solder joint formation. Temperature of the heat treatment of the comparative example 2 in the 280 ° C, hold time is 5 minutes, lowering temperatures speed was 10 ° C per second and. Example 2 is the 90Sn8Sb2Ag solder (Sn up 90. 0% by weight, 8 with Sb. 0% by weight, and 2 with Ag. Solder contains 0 WT %) from a formed by using a uniform paste solder solder joint formation. Example 2 annealing temperature at 270 ° C, holding time is 5 minutes, lowering temperatures speed was 10 ° C per second and.

[0082]

SN 97% by weight and samples containing 3% by weight Ag, i.e. the Sb content to 0% and the Ag content of 3% by weight and a ♦ mark (power-cycle reliability tolerance = 100%), conventional SN-AG system solder bonding layer shows the (comparative example 2). Comparative example 2 baseline as shown in Figure 5 axis power cycling reliability tolerance (%) have been calculated. On the horizontal axis of Figure 5 indicates the Sb content (% by weight). Also in low melting point solder alloy melting point 260 ° C indicate near and so further left than the standard line 51 Figure 5 standard line 51 shows that the move to the right than the standard line 51, high melting point. Shows cross section diagram 4 B indicating the State of comparative example 2 solder joint formation power cycle reliability testing. Figure 4b in section indicating the State of comparative example 2 solder joint formation power cycle reliability testing.

[0083]

In addition, these examples 1-3 composition was in as a result of the analysis as follows. The first crystals of the Sn atom: Atom = 1: p (0 < p ≤ 0. 1) is the second Crystal part No. 1 intermetallic compounds (part 1) is the Ag3Sn's (Sn atom: Atom = 1:03) compounds and Ag4Sn (Sn atom: Atom = 1:04) compounds in the Sn atom: Atom = 1: q (2 ≤ q ≤ 5) of ranged. Also, no. 2 Crystal of no. 2 between the compounds (part 2), Cu6Sn5's (Sn atom:Cu Atom = 5:06) Sn compound, Cu3(Sn atom:Cu Atom = 1:03) compounds, such as Lord, has the Sn atom:Cu Atom = 1: r (0. 4 ≤ r ≤ 4) of ranged. 3 crystal of SnSb's (Sn atom: Atom = 1:01) Sn compounds and Sb23(Sn atom: Atom = 3:02) compounds in the Sn atom: Atom = 1: s (0... 8 ≤ s ≤ 1. 6) of ranged. And Crystal 1st Crystal is the average grain diameter is smaller than the average grain diameter were observed by cross-sectional scanning electron MICROSCOPE study.

[0084]

From the results shown in Figure 5, example 1-confirmed that can improve power cycling reliability tolerance than comparative example 2 by 3, Sb content to 0% more than many. In addition, confirmed that can improve the Sb content increases as power cycling reliability tolerance. Confirmed that power cycling reliability tolerance obtained power cycling reliability tolerance is twice as much of the comparative example 2 in the vicinity of 250 ° C (melting point of the solder alloy for example 1, 2), and in the vicinity of 290 ° C (melting point of the solder alloy for example 3) greater than twice the comparative example 2. These examples 1-cracks are detected, as shown Figure 3 A, 3 B, 3. Therefore, semiconductor equipment to the present invention was found that enough for new energy applications of semiconductor and semiconductor device mounted on the car for instance is used in about 175 ° C, high reliability is required. Confirmed that, as well as the legacy, on the other hand, if the comparative example 2 fig. 4B as shown, no SB SN-AG system solder solder bonding layer 40 AgSn compounds 42 diameter to 5 μm experiences roughening from cracked 44. This caused by the inferior power cycling reliability tolerance is possible. In addition, confirmed that too increases the Sb content of 15 weight percent more often (if you went to the right of the dotted lines in Figure 5 code 52), melting point of the solder alloy, solder wettability to decrease. For this reason, Sb content of solder joint formation 11, 12 should be less than 15% by weight 0% more than many of.

[0085]

To explain the Ag content of solder joint formation 11, 12. Figure 6 is a characteristics diagram showing relation of Ag content of semiconductor device and power cycling reliability tolerance. SN (100-x-y) was measured by WT %, Sb x % by weight Ag, including, and y % by weight (100-x-y) SnxSbyAg solder alloy solder bonding layer 11, 12 full power cycling reliability tolerance shown in Figure 6.

[0086]

SN 97% by weight and samples containing 3% by weight Ag, i.e. the Sb content to 0% and the Ag content of 3% by weight and the ▲ mark (power-cycle reliability tolerance = 100%), where comparative example 2 above. This comparative example 2 baseline as shown in Fig. 6 vertical power cycling reliability tolerance (%) has been calculated. On the horizontal axis of Figure 6 show Ag-content (% by weight). Also, Sn 87% by weight and 13% with samples containing 13% Sb or Sb content and Ag content with 0% and ♦ mark (power-cycle reliability tolerance = 150%), Sn-Sb of solder joint formation of traditional shows (comparative example 1).

[0087]

Confirmed the results shown in Figure 6, the Sb content 0% more than more and improve power cycling reliability tolerance than the comparative examples 1, 2 by Ag amount to 0% more than many can afford. In addition, confirmed that can improve power cycling reliability tolerance increases the amount of Ag content. Confirmed or reduced solderability, Ag content 3% by weight than even if there are (if it went beyond the dotted line shown in code 53), and rising material costs. For this reason, Ag content of solder joint formation 11, 12 should be less than 3% by weight 0% more than many of.

[0088]

More effectively and regularly arranged according to the embodiment (example 2) as mentioned earlier, the, form a uniform microstructure, SB solid containning 1 dispersed crystal of (Sn grain) and matrix 1 multiple secondary precipitates at the grain boundary of Crystal, composed by Crystal and solder joint formation, have been strengthened. 2 No. 1 crystalline Crystal average particle diameter is of average grain size smaller than no. 1 Crystal average particle diameter is 30 m, and 2 0 is the average grain size of Crystal. Was in the 8 μm. 1st Crystal, at the solid-1st Crystal by Sb doped for the Department as a whole in solid solution strengthening, due to thermal loads such as power cycle first able to suppress a coarsening of the Crystal. 1st Crystal 2 harder than of fine grained matrix distributed in a crystalline part No. 1 intermetallic compounds (compounds containing Sn and Ag) by the first enhanced grain boundary between the crystals of the first hard to transform crystals, crystals. You can, power cycling reliability of SN-AG system solder bonding layer and to inhibit the growth of grains in a crack and grain boundary cracks Sn-Sb series solder bonding layer more than this.

[0089]

Also, according to the embodiment (examples 1, 3), 1st Crystal reacts with beyond the solubility limit part of the Sb 3 1st Crystal by Crystal, that make up the layer of solder joint strain due to stress because, that can be difficult to further deformation of crystalline. And no. 3 Crystal 1st Crystal is able to further reduce the grain in the cracks of more rigid and therefore. You can power cycle reliability tolerance to further improve this. Also, according to the embodiment, the Crystal is formed by the junction on the solder and Cu members and power cycle heat load of no. 2 metal intermetallic compounds (compounds containing Sn and Cu) with even better, no. 2 Crystal first distributed as a matrix as no. 1 compound (part 1), plus, further including a no. 2 intermetallic compounds (part 2) by grain boundary between the crystals, further strengthened. This enables conventional SN-AG system solder joint formation and to further reduce the intergranular crack propagation Sn-Sb of solder joint formation than even that. Therefore, you can power-cycle reliability tolerance to further improve.

[0090]

Also, not according to the embodiment, the Ag-doped to be no. 1, Crystal, or 3 can be lower than 300 ° C, for example 260 ° C (for example about 230 ° C) temperatures and melting point of the solder joint formation by forming a given grain size and composition of the Crystal. That is, you can get the soldering process at temperatures lower than 300 ° C SN-SB series conventional soldering process at a temperature of 300 ° C or higher is required or solder joint formation higher power cycle reliability tolerance, so that. You can provide reliable can reduce the thermal load on the equipment because at 300 ° C lower temperature soldering process possible, the adverse effects caused by thermal load less than conventional equipment. By using the mixed paste, by mixing the powder first according to the embodiment, including the Sb and no. 2 powder that does not contain Sb and solder bonding layer forming than to form solder joint formation consisting of one alloy powder homogeneous paste solder bonding layer further 1-3 Crystal Department arranged substantial and regular uniform microstructure can be. And power cycling reliability capacity example 4 is 230 (%) was 240 (%) in example 5. In this way, 1-3 Crystal Department arranged substantial and regular uniform microstructure and no. 1 and no. 2 can improve power cycling reliability by the refinement of Crystal.

[0091]

In more than the invention is not limited to the embodiments described above, be modified with range conform to the purpose of the present invention. You could for example, have both you solder bonding layers of multiple semiconductor devices, if these solder joints layer configuration described above within the same composition have a different composition.

Industrial applicability

[0092]

Take invention, like the more than semiconductor device and semiconductor device manufacturing method is useful in semiconductor device package structure through the layer of solder joints bonded parts such as semiconductor chips and circuit pattern.

Sign description

[0093]

1 chip
2 insulation Board
3 insulation layer
4th circuit pattern (foil).
5 copper bottom
6 copper-based
11, 12 solder bonding layer
21 1st Crystal Department (SB-doped Sn grain)
22 Crystal,
22-1 No. 1 metal intermetallic compounds (compounds containing Sn and Ag)
22-2 No. 2 intermetallic compounds (compounds containing Sn and Cu)
23 no. 3 crystals of (1 crystals of the first grain Sn, Sb to the Crystal of solid solubility limit has been exceeded and response)

Of the claims

[Paragraph 1]

Joined together by solder bonding layer configuration between a pair of semiconductor device
The solder bonding layer
Tin atoms: antimony atoms = 1 p (0 < p ≤ 0. 1) of no. 1 containing Tin and antimony in the ratio of Crystal and
Tin Atom AG atoms = 1: q (2 ≤ q ≤ 5) for part 1 ratio with Tin, silver, and, and the Tin atoms: CU atoms = 1: r (0. 4 ≤ r ≤ 4) of having at least one second part containing Tin and copper in a ratio of 2 crystals, and the
Mentioned in part 2 above average grain size of Crystal, 1st Crystal Semiconductor device to be smaller than the average grain diameter.

[Paragraph 2]

Wherein solder bonding layers is Tin atoms: antimony atoms = 1: s (0... 8 ≤ s ≤ 1. 6) of containing Tin and antimony in the ratio 3 to claim 1 characterized to possess a crystal of semiconductor equipment listed.

[Invoice section 3]

First Crystal of the antimony solid to claim 1 characterized by doped tin grain in semiconductor equipment.

[Paragraph 4]

First Crystal of the antimony-doped tin grain in the
Said the third 1st Crystal Crystal Division, said, and the first to claim 2 be characterized by reacting antimony to the Crystal of solid solubility limit has been exceeded and the grain in semiconductor equipment.

[Bill 5]

Wherein said second 1st Crystal crystallization of the above-mentioned claim 1 characterized to have precipitated at grain boundaries between in semiconductor equipment.

[Bill 6]

The average diameter of the above part 1 on claim 1 characterized by 1 μm in semiconductor equipment.

[Billing paragraph 7]

Is the melting point of solder bonding layer in claim 1 characterized by 260 ° C or less in semiconductor equipment.

[Claim 8]

By solder bonding layer configuration between a pair of bonded semiconductor device manufacturing method
Step on one of the above configuration applying solder paste containing a mixture containing antimony alloy powder and powder that does not contain antimony
Solidified by heat treatment wherein solder paste solder bonding layer formed, wherein solder joint formation by joining the above configuration of each process, including
The solder bonding layer
Tin atoms: antimony atoms = 1 p (0 < p ≤ 0. 1) of no. 1 containing Tin and antimony in the ratio of Crystal and
Tin Atom AG atoms = 1: q (2 ≤ q ≤ 5) for part 1 ratio with Tin, silver, and, and the Tin atoms: CU atoms = 1: r (0. 4 ≤ r ≤ 4) of having at least one second part containing Tin and copper in a ratio of 2 crystals, and the
Mentioned in part 2 above average grain size of Crystal, 1st crystal manufacturing method of semiconductor device to be smaller than the average grain diameter.