WO2017188206A1 - Joining material and joining method using same - Google Patents

Abstract

Provided are a joining material and a joining method using the same, which, even if the thickness of a coating film is increased, can prevent inclusion of bubbles when the coating film is formed, and thus can prevent generation of a void in a silver joining layer. In the joining material formed from silver paste that contains silver particulates, solvents, and an additive, the solvents include a first solvent comprising a diol such as octanediol and a second solvent comprising a polar solvent (preferably, at least one selected from the group consisting of dibutyldiglycol, hexyldiglycol, decanol, and dodecanol) having a surface tension lower than the first solvent, and the additive is a triol.

Description

Bonding material and bonding method using the same

The present invention relates to a bonding material and a bonding method using the same, and in particular, a bonding material made of a silver paste containing silver fine particles and an electronic component such as a Si chip on a metal substrate such as a copper substrate using the bonding material. On how to do.

In recent years, silver paste containing silver fine particles is used as a bonding material, and the bonding material is interposed between the objects to be bonded and heated, thereby sintering the silver in the bonding material and bonding the objects to be bonded together. Has been proposed (see, for example, Patent Documents 1 and 2).

When fixing an electronic component such as a Si chip on a metal substrate such as a copper substrate using such a bonding material, a silver paste in which silver fine particles are dispersed in a solvent is applied on the substrate, and then heated to remove the solvent. The pre-dried film is formed on the substrate by removing the electronic component, and after placing the electronic component on the pre-dried film, the electronic component is heated via the silver bonding layer by heating the electronic component while applying pressure. Can be joined.

Japanese Patent Laying-Open No. 2011-80147 (paragraph numbers 0014-0020) JP 2016-8332 A (paragraph number 0009-0012)

However, when a conventional bonding material made of a silver paste containing silver fine particles, such as the bonding material of Patent Documents 1 and 2, is printed on a substrate to a thickness of 150 μm or more with a metal mask and a metal squeegee to form a thick coating film. Rotating (rolling) the silver paste between the metal mask and the metal squeegee during printing causes foam biting (no gas or other gas is mixed into the uniform state), causing bubbles in the coating film. It becomes easy to be involved, and the foam formed on this coating film forms irregularities on the surface of the pre-dried film, or cracks and peeling easily occur on the pre-dried film. Due to cracks in the pre-dried film, voids are likely to occur in the silver bonding layer, and the reliability and heat dissipation of the bonding material are likely to decrease. In particular, when bonding a SiC device that requires high temperature reliability onto a substrate, it may be necessary to make the bonding layer sufficiently thick in order to ensure high temperature reliability. Therefore, if the coating film is thickened and the pre-dried film is thickened, the shrinkage of the pre-dried film increases, and the surface of the pre-dried film becomes uneven and cracks and peeling of the pre-dried film are more likely to occur.

Therefore, in view of such a conventional problem, the present invention can prevent the occurrence of voids in the silver bonding layer by preventing bubble biting during the formation of the coating film even if the coating film is thickened. An object of the present invention is to provide a bonding material and a bonding method using the same.

As a result of diligent research to solve the above problems, the present inventors have found that in a bonding material comprising silver paste containing silver fine particles, a solvent and an additive, a first solvent comprising a diol as the solvent and the first solvent. By using a second solvent composed of a polar solvent having a lower surface tension and using triol as an additive, even if the coating film is thickened, it prevents foam biting during the formation of the coating film, and silver bonding It has been found that it is possible to provide a bonding material and a bonding method using the same, which can prevent generation of voids in the layer, and the present invention has been completed.

That is, the bonding material according to the present invention includes a first solvent made of diol as a solvent and a polar solvent having a lower surface tension than the first solvent in the bonding material made of silver paste containing silver fine particles, a solvent, and an additive. And the additive is a triol.

In this bonding material, the first solvent is preferably octanediol. The second solvent is preferably at least one selected from the group consisting of dialkyl glycol ethers, ethylene glycol ethers and monoalcohols, and is selected from the group consisting of dibutyl diglycol, hexyl diglycol and decanol. More preferably, it is a seed or more. The average primary particle diameter of the silver fine particles is preferably 1 to 100 nm, and the content of the silver fine particles in the bonding material is preferably 60 to 90% by mass. Further, the bonding material may contain silver particles having an average particle diameter of 0.2 to 10 μm. In this case, the content of silver particles having an average particle size of 0.2 to 10 μm in the bonding material is 30% by mass or less, and the content of silver fine particles and the content of silver particles having an average particle size of 0.2 to 10 μm The total is preferably 60 to 90% by mass. The silver fine particles are preferably coated with an organic compound having 8 or less carbon atoms, and the organic compound is preferably sorbic acid. Further, the content of the first solvent in the bonding material is preferably 5 to 20% by mass, the content of the second solvent is preferably 0.5 to 15% by mass, and the additive content is The amount is preferably from 0.5 to 10% by weight. Further, the bonding material may include a sintering aid. In this case, the sintering aid is preferably diglycolic acid or malonic acid, and the content of the sintering aid in the bonding material is preferably 0.001 to 0.1% by mass.

Further, the bonding method according to the present invention includes the above-described bonding material interposed between the objects to be bonded, and heated to sinter the silver in the bonding material to form a silver bonding layer. It is characterized by joining joined objects.

In the present specification, the “average primary particle diameter of silver fine particles” means the average value of primary particle diameters determined by a scanning electron microscope (SEM) or transmission electron micrograph (TEM image) of silver fine particles. Say.

ADVANTAGE OF THE INVENTION According to this invention, even if it thickens a coating film, it can prevent a bubble biting at the time of formation of a coating film, and can prevent that a void arises in a silver joining layer, and a joining method using the same Can be provided.

In the embodiment of the bonding material according to the present invention, in the bonding material made of silver paste containing silver fine particles, a solvent and an additive, the solvent is a first solvent made of diol, and the surface tension is lower than that of the first solvent. A second solvent composed of a polar solvent, and the additive is triol. In this way, the second solvent composed of a polar solvent having a surface tension lower than that of the first solvent is added as an antifoaming agent to reduce the surface tension of the solvent, and by adding triol, the coating film is thickened. Even in this case, it is possible to prevent the occurrence of voids in the silver bonding layer by preventing foam biting during the formation of the coating film.

In the embodiment of the bonding method according to the present invention, the above-mentioned bonding material is interposed between the objects to be bonded and heated, so that the silver in the bonding material is sintered to form a silver bonding layer. The objects to be joined are joined together. For example, after placing an electronic component on a pre-dried film bonding material obtained by pre-drying a coating film obtained by applying the bonding material on a copper substrate, while applying pressure to the electronic component By heating, silver in the silver paste is sintered to form a silver bonding layer, and the electronic component is bonded to the copper substrate via the silver bonding layer. If the above-mentioned bonding material is used, when forming a thick coating film of about 200 μm on the substrate, it prevents foam biting, prevents cracking and peeling of the pre-dried film, and applies a low pressure of about 5 MPa. Even if it heats, it can prevent that a void arises in a silver joining layer, and it can join to-be-joined objects with high joining force.

In the above bonding material embodiment, the first solvent is a diol (having two hydroxyl groups), and the bonding material is heated to sinter silver in the silver paste to form a silver bonding layer. In this case, it is preferable that the solvent does not remain in the silver bonding layer due to evaporation or decomposition. In addition, the silver fine particles in the bonding material can be heated at a low temperature of 200 to 300 ° C. (preferably 210 to 290 ° C.) to sinter the silver to form a silver bonding layer. The boiling point is preferably 200 to 300 ° C, more preferably 210 to 290 ° C. The average surface tension of the first solvent is preferably 31.4 to 37.4 dyne / cm. The surface tension can be measured by, for example, a fully automatic surface tension meter (CBVP-Z manufactured by Kyowa Interface Chemical Co., Ltd.). Further, the viscosity of the first solvent is 25 ° C. so that a thick coating film of 150 μm or more can be formed by the silver paste in which the first solvent is added to the silver fine particles together with the second solvent and the additive. The pressure is preferably 1 to 300 mPa · s, more preferably 50 to 200 mPa · s. As such a first solvent, a diol having 3 to 10 carbon atoms is preferably used, and a diol having 3 to 8 carbon atoms is more preferably used. Moreover, it is preferable that such a 1st solvent is diol which has a branch.

As such a first solvent, specifically, octanediol (ODO) (2-ethyl-1,3-hexanediol, boiling point 243.0 ± 8.0 ° C., viscosity (25 ° C.) 178 mPa · s, It is preferable to use a surface tension (25 ° C.) of 34.4 ± 3.0 dyne / cm (average value 34.4 dyne / cm)). In addition, as a 1st solvent, 1 type of diol may be used and 2 or more types of diol may be used. The content of the first solvent in the bonding material is preferably 5 to 20% by mass, and more preferably 7 to 18% by mass.

The second solvent is a polar solvent having a surface tension lower than that of the first solvent. By adding such a polar solvent having a surface tension lower than that of the first solvent, the surface tension of the entire solvent can be reduced, so that the coating film is made thicker than when only the first solvent is used. Even in this case, it is possible to prevent the occurrence of voids in the silver bonding layer by preventing foam biting during the formation of the coating film. In addition, the polar solvent that can be used as the second solvent preferably has a certain degree of compatibility with the first solvent. Moreover, the polar solvent which has a hydroxyl group, an ether bond, an amino group, and a carboxyl group can be used as a 2nd solvent, It is preferable to use the polar solvent which has a hydroxyl group and an ether bond. In addition, when it is a polar solvent which has a hydroxyl group as a 2nd solvent, it is preferable to use polar solvents (it has 1 or 4 or more of hydroxyl groups) other than diol and a triol.

Similarly to the first solvent, the second solvent is heated in the silver bonding layer by evaporation or decomposition when the bonding material is heated to sinter silver in the silver paste to form a silver bonding layer. It is preferable that the solvent does not remain in the solvent. Further, the boiling point of the second solvent is 200 to 300 ° C. so that the silver fine particles in the bonding material can be heated at a low temperature of 200 to 300 ° C. to sinter the silver to form a silver bonding layer. Is preferred. Moreover, it is preferable that the average value of the surface tension of the second solvent is 2.0 dyne / cm or more lower than the surface tension of the first solvent. Further, the viscosity of the second solvent is 25 ° C. so that a thick coating film of 150 μm or more can be formed by the silver paste in which the second solvent is added to the silver fine particles together with the first solvent and the additive. The pressure is preferably 1 to 200 mPa · s, more preferably 1 to 100 mPa · s. As such a second solvent, glycol ethers (such as dialkyl glycol ethers and ethylene glycol ethers) and monoalcohols are preferably used, and glycol ethers and monoalcohols having 8 to 12 carbon atoms are further used. preferable.

Specifically, as such a second solvent, dibutyl diglycol (DBDG) (boiling point 254.6 ° C., viscosity (25 ° C.) 2.4 mPa · s, surface tension (25 ° C.) 28.7 ± 3. 0 dyne / cm (average value 28.7 dyne / cm)), hexyl diglycol (HeDG) (boiling point 260 ° C., viscosity (25 ° C.) 8.6 mPa · s, surface tension (25 ° C.) 32.3 ± 3.0 dyne / cm (average value 32.3 dyne / cm)), 1-decanol (boiling point 227.8 ± 3.0 ° C., viscosity (25 ° C.) 1.38 mPa · s, surface tension (25 ° C.) 29.9 ± 3.0 dyne) / Cm (average value 29.9 dyne / cm)), 1-dodecanol (boiling point 258 ° C., viscosity (25 ° C.) 18-20 mPa · s, surface tension (25 ° C.) 30.4 ± 3.0 dyne / cm (average value) 30.4 dy ne / cm)) and the like, and dibutyl diglycol (DBDG), hexyl diglycol (HeDG) or 1-decanol is preferably used. In addition, as a 2nd solvent, 1 type of a polar solvent whose surface tension is lower than a 1st solvent may be used, and 2 or more types may be used. The content of the second solvent in the bonding material is preferably 0.5 to 15% by mass, and more preferably 0.7 to 12% by mass.

Since the triol used as an additive has three hydroxyl groups, the dispersibility with the first solvent and the second solvent is good, and the silver added to the silver fine particles together with the first solvent and the second solvent. Even if the coating film is thickened by the paste, it is possible to prevent bubbles from forming during the formation of the coating film and to prevent voids from being generated in the silver bonding layer.

Further, the triol used as an additive is evaporated or heated when the bonding material is heated to sinter silver in the silver paste to form a silver bonding layer, in the same manner as the first solvent and the second solvent. A triol that does not remain in the silver bonding layer due to decomposition or the like is preferable. Further, the boiling point of the second solvent is 200 to 300 ° C. so that the silver fine particles in the bonding material can be heated at a low temperature of 200 to 300 ° C. to sinter the silver to form a silver bonding layer. Is preferred. The surface tension of the triol used as an additive is preferably 30 to 50 dyne / cm, and more preferably 30 to 40 dyne / cm, so that the surface tension of the solvent does not increase. Further, the viscosity of the triol is 25 ° C. so that a thick coating film of 150 μm or more can be formed by the silver paste obtained by adding the triol used as an additive to the silver fine particles together with the first solvent and the second solvent. In this case, it is preferably 2000 to 10000 mPa · s, and more preferably 4000 to 10000 mPa · s. As such a triol, a triol having 3 to 8 carbon atoms is preferably used, and a triol having 3 to 6 carbon atoms is more preferably used. In order to improve the compatibility with the first solvent, it is preferable that such a triol is a triol having a branch. This branch may be formed by a hydrocarbon group or may be formed by a hydroxyl group.

As such a triol, specifically, 2-methyl-butane-2,3,4-triol (isoprenetriol A (IPTL-A)) (boiling point 255.5 ° C., viscosity (25 ° C.) 5420 mPa · s, Surface tension (25 ° C.) 38.7 dyne / cm) and 2-methyl-butane-1,3,4-triol (isoprene triol B (IPTL-B)) (boiling point 278-282 ° C., viscosity (25 ° C.) 4050 mPa S, surface tension (25 ° C.) 47.5 ± 1.0 dyne / cm (average value 47.5 dyne / cm)) can be used, and 2-methyl-butane-2,3,4-triol ( Isoprenetriol A (IPTL-A)) is preferably used. As an additive, one type of triol may be used, or two or more types of triol may be used. The content of triol as an additive in the bonding material is preferably 0.5 to 10% by mass, and more preferably 1 to 7% by mass.

Also, the bonding material may contain a sintering aid. The sintering aid is preferably a dicarboxylic acid having 2 to 6 carbon atoms, more preferably diglycolic acid or malonic acid. The content of the sintering aid in the bonding material is preferably 0.001 to 0.1% by mass, and more preferably 0.005 to 0.05% by mass.

The average primary particle diameter of the silver fine particles is 1 to 100 nm so that the silver fine particles in the bonding material can be heated at a low temperature of 200 to 300 ° C. to sinter the silver to form a silver bonding layer. Is more preferable, and 40 to 100 nm is more preferable. Further, the content of the silver fine particles in the bonding material is preferably 60 to 90% by mass, and more preferably 75 to 90% by mass.

Further, the bonding material may contain silver particles having an average particle diameter of 0.2 to 10 μm, preferably 0.3 to 1 μm. Such micron-sized silver particles are connected to each other by the fused silver fine particles when the silver fine particles in the bonding material are heated at a low temperature of 200 to 300 ° C. to sinter the silver, and the silver bonding layer as a whole. Can be formed. In this case, the content of silver particles having an average particle size of 0.2 to 10 μm in the bonding material is 30% by mass or less, and the content of silver fine particles and the content of silver particles having an average particle size of 0.2 to 10 μm The total is preferably 60 to 90% by mass.

The silver fine particles are preferably coated with an organic compound having 8 or less carbon atoms (for example, a fatty acid or amine having 8 or less carbon atoms) in order to prevent aggregation in the bonding material. As such an organic compound, sorbic acid or hexanoic acid can be used, and sorbic acid is preferably used so that the dispersibility with the first solvent and the second solvent is improved.

The average primary particle size of the silver fine particles may be determined, for example, by scanning the silver fine particles with a scanning electron microscope (SEM) (S-4700 manufactured by Hitachi High-Technologies Corporation) or a transmission electron microscope (TEM) (manufactured by JEOL Ltd.). JEM-1011) for a predetermined magnification (for example, if the particle size is 20 nm or less, 180,000 times by TEM, if it is larger than 20 nm and 30 nm or less, 80,000 times by SEM, larger than 30 nm and 100 nm or less) Can be calculated from the primary particle diameter of 100 or more arbitrary silver fine particles on an image (SEM image or TEM image) observed at 50,000 times by SEM. The average primary particle diameter of the silver fine particles can be calculated by, for example, image analysis software (A image-kun (registered trademark) manufactured by Asahi Kasei Engineering Co., Ltd.).

Further, the viscosity at 5 rpm measured at 25 ° C. of the bonding material is preferably 10 to 30 Pa · s, and more preferably 10 to 20 Pa · s. Further, the ratio of the viscosity of 1 rpm (3.1 [1 / S]) to the viscosity of 5 rpm measured at 25 ° C. of the bonding material (viscosity of 1 rpm / 5 viscosity of 5 rpm) (Ti value) is 3.0 to 5.0. Is preferred.

Hereinafter, embodiments of the bonding material according to the present invention and the bonding method using the same will be described in detail.

[Example 1]
180.0 g of pure water was placed in a 300 mL beaker, and 33.6 g of silver nitrate (manufactured by Toyo Chemical Co., Ltd.) was added and dissolved to prepare an aqueous silver nitrate solution as a raw material solution.

Further, 3322.0 g of pure water was put into a 5 L beaker, and the temperature was raised to 40 ° C. while nitrogen was passed through the pure water for 30 minutes to remove dissolved oxygen. After adding 44.8 g of sorbic acid (manufactured by Wako Pure Chemical Industries, Ltd.) as an organic compound (for silver fine particle coating) to this pure water, 28% ammonia water (manufactured by Wako Pure Chemical Industries, Ltd.) as a stabilizer. ) 7.1 g was added.

While stirring the aqueous solution after the addition of ammonia water, 14.91 g of hydrous hydrazine having a purity of 80% (manufactured by Otsuka Chemical Co., Ltd.) as a reducing agent was added after 5 minutes from the time of ammonia water addition (at the start of the reaction). By adding, a reducing agent-containing aqueous solution was prepared as a reducing solution. After 9 minutes from the start of the reaction, the raw material solution (silver nitrate aqueous solution) whose temperature was adjusted to 40 ° C. was added to the reducing solution (reducing agent-containing aqueous solution) all at once and reacted, and further stirred for 80 minutes. The liquid temperature was raised from 40 ° C. to 60 ° C. at a temperature rate of 1 ° C./min to complete the stirring.

After forming an aggregate of silver fine particles (silver nanoparticles) coated with sorbic acid in this way, a liquid containing the aggregate of silver fine particles is designated as No. 1 The mixture was filtered with 5C filter paper, and the recovered material was washed with pure water to obtain an aggregate of silver fine particles. The silver fine particle aggregate was dried in a vacuum dryer at 80 ° C. for 12 hours to obtain a dry powder of the silver fine particle aggregate. The silver fine particle aggregate dry powder thus obtained was crushed to adjust the size of the secondary aggregate. In addition, it was 85 nm when the average primary particle diameter of this silver fine particle was calculated | required with the scanning electron microscope (SEM).

Next, 86.0 g of dried powder (silver particles 1) of the aggregate of silver fine particles (coated with sorbic acid) whose secondary aggregate size was adjusted in this way, and the first solvent (solvent 1) ) As octanediol (ODO) (2-ethyl-1,3-hexanediol manufactured by Kyowa Hakko Chemical Co., Ltd., boiling point 243.0 ± 8.0 ° C., viscosity (25 ° C.) 178 mPa · s, surface tension (25 ° C) 34.4 ± 3.0 dyne / cm (average value 34.4 dyne / cm)) 9.89 g and dibutyl diglycol (DBDG) (manufactured by Nippon Emulsifier Co., Ltd., boiling point) as the second solvent (solvent 2) 254.6 ° C., viscosity (25 ° C.) 2.4 mPa · s, surface tension (25 ° C.) 28.7 ± 3.0 dyne / cm (average value 28.7 dyne / cm)) 1.10 g, 2-Methyl-butane-2 , 3,4-triol (Isoprene triol A (IPTL-A)) (manufactured by Nippon Terpene Chemical Co., Ltd., boiling point 255.5 ° C., viscosity (25 ° C.) 5420 mPa · s, surface tension (25 ° C.) 38.7 dyne / cm ) 3.0 g and 0.01 g of oxydiacetic acid (diglycolic acid (DGA)) (manufactured by Midori Chemical Co., Ltd.) as a sintering aid (sintering accelerator) were mixed. This mixture was kneaded for 30 seconds at a revolution speed of 1400 rpm and a rotation speed of 700 rpm by a kneading defoaming machine (V-mini300 type manufactured by EME Co., Ltd.). This kneaded product is diluted with a mixed solvent (Solmix AP-7 manufactured by Nippon Alcohol Sales Co., Ltd.), stirred, crushed with a wet jet mill (RM-L1000EP manufactured by Rix Corporation), and degassed by vacuum stirring. After defoaming with a mixer to evaporate all the mixed solvent (Solmix AP-7), 5.80 g of octanediol (ODO) and 0.64 g of dibutyldiglycol (DBDG) were added as diluent solvents, Joining composed of silver paste containing 80.8% by weight of silver particles 1, 14.73% by weight of ODO, 1.64% by weight of DBDG, 2.82% by weight of IPTL-A and 0.01% by weight of DGA The material was obtained.

When the viscosity of the bonding material was determined by a rheometer (a viscoelasticity measuring device) (HAAKE Rheoless 600 manufactured by Thermo, cone used: C35 / 2 °), it was 5 rpm (15.7 [1 / S]) at 25 ° C. The ratio of the viscosity at 1 rpm (3.1 [1 / S]) to the viscosity at 5 rpm measured at 25 ° C. (viscosity at 1 rpm / 5 viscosity at 5 rpm) (Ti value) is 3. 6. The viscosity is measured by measuring the shear rate at 1.6 [1 / S], 3.1 [1 / S], 6.3 [1 / S], 15.7 [1 / S], 31.3 [1]. / S], 62.7 [1 / S], and 156.7 [1 / S], and the viscosity was measured 20 seconds after each shear rate was reached. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.6 mass%.

The particle size of the silver particles contained in this bonding material (silver paste) was evaluated by a grind gauge (BYK 50 μm stainless steel) as follows. First, clean the grind gauge with an alcohol solvent (Solmix) and dry it thoroughly, then place 5-10 g of silver paste on the deep side of the grind gauge (50 μm side), and place the scraper with the thumbs of both hands. Place the scraper so that the long edge of the scraper is parallel to the width direction of the grind gauge and the blade tip is in contact with the deep tip of the grind gauge groove, and the scraper is perpendicular to the grind gauge surface In order to make it easy to see the pattern of the silver paste within 3 seconds after pulling the grind gauge in 1 to 2 seconds to the groove depth 0 at an even speed perpendicular to the long side of the groove. , The portion where a noticeable line begins to appear in the silver paste is perpendicular to the long side of the groove and from the direction of an angle of 20-30 ° to the surface of the grind gauge Observe and obtain the particle size of the first line (1st scratch, maximum particle size Dmax) and the fourth line (4th scratch) along the groove, and the average particle size as the particle size of 10 or more lines appearing uniformly D ₅₀ was obtained. In addition, since the sparse line before a remarkable line begins to appear is disregarded and there are one grind gauge on each of the left and right, the average value of the values indicated by the two is used as the measurement result. As a result, the 1st scratch was less than 20 μm, the 4th scratch was less than 10 μm, and the average particle size D ₅₀ was less than 5 μm.

Next, a metal mask having a thickness of 200 μm is placed on a 30 mm × 30 mm × 1 mm copper substrate (C1020), and the above-mentioned metal squeegee is used with a screen printer (SP18P-L manufactured by Panasonic FS Engineering Co., Ltd.). The bonding material (silver paste) was applied on the copper substrate so as to have a size of 10 mm × 10 mm and a thickness (printed film thickness) of 200 μm. When this coating film was observed with a 3D shape measuring instrument (Microscope VR-3200 manufactured by Keyence Corporation), no bubbles were observed in the coating film.

Thereafter, the copper substrate coated with the bonding material is placed on a metal bat, placed in an oven (manufactured by Yamato Kagaku Co., Ltd.), preheated by heating at 120 ° C. for 20 minutes in an air atmosphere, The solvent was removed to form a pre-dried film. When this pre-dried film was observed with a 3D shape measuring instrument (Microscope VR-3200 manufactured by Keyence Corporation), no cracks or peeling were observed in the pre-dried film.

Next, after cooling the copper substrate on which the pre-dried film is formed to 25 ° C., an SiC chip (8 mm × 8 mm in size) having a silver plating of 0.3 mm is disposed on the pre-dried film. This is installed in a hot press machine (manufactured by DOWA Electronics Co., Ltd.), heated up to 290 ° C. in about 120 seconds while applying a 5.0 MPa load in the atmosphere, and held for 90 seconds after reaching 290 ° C. Firing was performed to sinter silver in the silver paste to form a silver bonding layer, and a bonded body in which the SiC chip was bonded to the copper substrate by the silver bonding layer was obtained.

The bonded body thus obtained was observed for the presence or absence of voids in the silver bonding layer using an ultrasonic microscope (C-SAM manufactured by SONOSCAN). No voids were observed.

[Example 2]
The ODO addition amount as the solvent 1 was 9.34 g, the addition amount of DBDG as the solvent 2 was 1.65 g, and the addition amounts of ODO and DBDG as the dilution solvent were 6.91 g and 1.22 g, respectively. In the same manner as in Example 1, 79.5% by mass of silver particles 1, 15.06% by mass of ODO, 2.66% by mass of DBDG, 2.77% by mass of IPTL-A, and 0.01% by mass. A bonding material (silver paste) containing DGA was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.5 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.7.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 3]
The addition amount of ODO as the solvent 1 was 8.79 g, the addition amount of DBDG as the solvent 2 was 2.20 g, and the addition amounts of ODO and DBDG as the dilution solvent were 6.88 g and 1.72 g, respectively. In the same manner as in Example 1, 79.2% by mass of silver particles 1, 14.42% by mass of ODO, 3.61% by mass of DBDG, 2.76% by mass of IPTL-A, and 0.01% by mass. A bonding material (silver paste) containing% DGA was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.3 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.8.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 4]
The addition amount of ODO as the solvent 1 is 8.09 g, the addition amount of DBDG as the solvent 2 is 0.90 g, the addition amount of IPTL-A as the additive is 5.0 g, and the addition amounts of ODO and DBDG as the dilution solvent Except for addition amounts of 5.56 g and 0.62 g, respectively, 81.0% by mass of silver particles 1, 12.85% by mass of ODO and 1.43% by mass of DBDG were obtained in the same manner as in Example 1. And a bonding material (silver paste) containing 4.71% by mass of IPTL-A and 0.01% by mass of DGA. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.8 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.7.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 5]
The addition amount of ODO as the solvent 1 is 11.24 g, the addition amount of DBDG as the solvent 2 is 1.25 g, the addition amount of IPTL-A as the additive is 1.5 g, and the addition amounts of ODO and DBDG as dilution solvents Except for the addition amounts of 6.41 g and 0.71 g, respectively, 80.3% by mass of silver particles 1, 16.46% by mass of ODO and 1.83% by mass of DBDG were obtained in the same manner as in Example 1. And 1.40 mass% IPTL-A and 0.01 mass% DGA-containing bonding material (silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.1 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.4.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 6]
Instead of DBDG as solvent 2, hexyl diglycol (HeDG) (manufactured by Nippon Emulsifier Co., Ltd., boiling point 260 ° C., viscosity (25 ° C.) 8.6 mPa · s, surface tension (25 ° C.) 32.3 ± 3.0 dyne / cm (Average value 32.3 dyne / cm)) 1.10 g was added, and 80.80 was added in the same manner as in Example 1 except that 5.93 g of ODO and 0.66 g of HeDG were added instead of ODO and DBDG as diluent solvents. A bonding material (silver paste) containing 7% by mass of silver particles 1, 14.83% by mass of ODO, 1.65% by mass of HeDG, 2.81% by mass of IPTL-A, and 0.01% by mass of DGA. Obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.5 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.5.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 7]
Instead of DBDG as solvent 2, 1-decanol (manufactured by Wako Pure Chemical Industries, Ltd., boiling point 227.8 ± 3.0 ° C., viscosity (25 ° C.) 1.38 mPa · s, surface tension (25 ° C.) 29.9 ± Example 1 except that 1.10 g of 3.0 dyne / cm (average value 29.9 dyne / cm) was added and 5.33 g of ODO and 0.59 g of 1-decanol were added in place of ODO and DBDG as diluent solvents. In the same manner, 81.2% by weight of silver particles 1, 14.36% by weight of ODO, 1.60% by weight of 1-decanol, 2.83% by weight of IPTL-A and 0.01% by weight of A joining material (silver paste) containing DGA was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 80.0 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.5.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 8]
The amount of ODO added as solvent 1 was 8.79 g (8.79% by mass), and as solvent 2, 1.20 g of 1-decanol (Wako Pure Chemical Industries, Ltd.) was added instead of DBDG as a diluent solvent. Except for adding ODO 4.84 g and 1-decanol 1.21 g instead of ODO and DBDG, the same procedure as in Example 1 was performed, and 81.1% by mass of silver particles 1 and 12.85% by mass of ODO and 3 A bonding material (silver paste) containing .21% by mass of 1-decanol, 2.83% by mass of IPTL-A and 0.01% by mass of DGA was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.9 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.6.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 9]
180.0 g of pure water was placed in a 300 mL beaker, and 33.6 g of silver nitrate (manufactured by Toyo Chemical Co., Ltd.) was added and dissolved to prepare an aqueous silver nitrate solution as a raw material solution.

Further, 3322.0 g of pure water was put into a 5 L beaker, and the temperature was raised to 60 ° C. while nitrogen was passed through the pure water for 30 minutes to remove dissolved oxygen. After adding 44.8 g of sorbic acid (manufactured by Wako Pure Chemical Industries, Ltd.) as an organic compound (for silver fine particle coating) to this pure water, 28% ammonia water (manufactured by Wako Pure Chemical Industries, Ltd.) as a stabilizer. ) 7.1 g was added.

While stirring the aqueous solution after the addition of ammonia water, 14.9 g of hydrous hydrazine having a purity of 80% (manufactured by Otsuka Chemical Co., Ltd.) was added as a reducing agent after 5 minutes from the addition of ammonia water (at the start of the reaction). By adding, a reducing agent-containing aqueous solution was prepared as a reducing solution. After 9 minutes from the start of the reaction, a raw material solution (silver nitrate aqueous solution) whose liquid temperature was adjusted to 60 ° C. was added to the reducing solution (reducing agent-containing aqueous solution) all at once and reacted. Stirring was terminated when 25 minutes had elapsed from the start of the reaction.

After forming an aggregate of silver fine particles (silver nanoparticles) coated with sorbic acid in this way, a liquid containing the aggregate of silver fine particles is designated as No. 1 The mixture was filtered with 5C filter paper, and the recovered material was washed with pure water to obtain an aggregate of silver fine particles. The silver fine particle aggregate was dried in a vacuum dryer at 80 ° C. for 12 hours to obtain a dry powder of the silver fine particle aggregate. The silver fine particle aggregate dry powder thus obtained was crushed to adjust the size of the secondary aggregate. In addition, it was 60 nm when the average primary particle diameter of this silver fine particle was calculated | required with the scanning electron microscope (SEM).

Next, 21.5 g of dry powder (silver particles 2) of the aggregate of silver fine particles (coated with sorbic acid) whose secondary aggregate size was adjusted in this way, and the same method as in Example 1 64.5 g of an aggregate of silver fine particles (coated with sorbic acid) (silver particle 1) having an average primary particle diameter of 85 nm obtained by the above method was used as a dry powder of the aggregate of silver fine particles, and diluted solvent 59.7% by mass of silver particles 1 and 19.9% by mass of silver particles 2 in the same manner as in Example 1 except that the addition amounts of ODO and DBDG as are 7.19 g and 0.80 g, respectively. And 15.85% by mass of ODO, 1.76% by mass of DBDG, 2.78% by mass of IPTL-A and 0.01% by mass of DGA were obtained (silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.2 mass%.

When the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, the 1st scratch was less than 20 μm, the 4th scratch was less than 10 μm, and the average particle size D50 was less than 5 μm. . Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.7.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 10]
Example except that 0.01 g of malonic acid was used instead of oxydiacetic acid (diglycolic acid) as a sintering aid, and the addition amounts of ODO and DBDG as dilution solvents were 7.44 g and 0.83 g, respectively. In the same manner as in No. 9, 58.5% by mass of silver particles 1, 19.5% by mass of silver particles 2, 17.34% by mass of ODO, 1.93% by mass of DBDG, and 2.72% by mass of IPTL. A bonding material (silver paste) containing -A and 0.01% by mass of malonic acid was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.0 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.8.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 11]
After obtaining a dry powder of an aggregate of silver fine particles (coated with sorbic acid) in the same manner as in Example 9, 61.5 g of the dry powder (silver particle 2) of the aggregate of silver fine particles and a micron size 20.5 g of silver particles AG2-1C (manufactured by DOWA Electronics Co., Ltd., average particle size (average primary particle size obtained from SEM image) 0.3 μm) (silver particles 3) were aggregated with silver fine particles of Example 1 The amount of ODO added as solvent 1 was 8.25 g, the amount of DBDG added as solvent 2 was 8.25 g, the amount of IPTL-A added as an additive Example 1 except that the amount of ODO and DBDG added as dilution solvents was 1.98 g and 1.98 g, respectively, and oxydiacetic acid (diglycolic acid) was not added as a sintering aid. 1 and According to the same method, 59.2% by weight of silver particles 2, 19.7% by weight of silver particles 3, 9.83% by weight of ODO, 9.83% by weight of DBDG and 1.44% by weight of IPTL-A A bonding material (silver paste) containing was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.2 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.9.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 12]
The addition amount of ODO as solvent 1 was 9.90 g, the addition amount of DBDG as solvent 2 was 6.60 g, and the addition amounts of ODO and DBDG as dilution solvents were 2.14 g and 1.43 g, respectively. In the same manner as in Example 11, 59.4% by mass of silver particles 2, 19.8% by mass of silver particles 3, 11.61% by mass of ODO, 7.74% by mass of DBDG and 1.45% by mass. % Of IPTL-A was obtained as a bonding material (silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.5 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.9.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 13]
The addition amount of ODO as the solvent 1 was 11.55 g, the addition amount of DBDG as the solvent 2 was 4.95 g, and the addition amounts of ODO and DBDG as the dilution solvent were 2.13 g and 0.91 g, respectively. In the same manner as in Example 11, 59.7% by mass of silver particles 2, 19.9% by mass of silver particles 3, 13.26% by mass of ODO, 5.68% by mass of DBDG and 1.46% by mass. % Of IPTL-A was obtained as a bonding material (silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.9 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.9.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 14]
The addition amount of ODO as the solvent 1 is 13.20 g, the addition amount of DBDG as the solvent 2 is 3.30 g, and the addition amounts of ODO and DBDG as the dilution solvent are 2.02 g and 0.50 g, respectively. In the same manner as in Example 11, 60.0% by mass of silver particles 2, 20.0% by mass of silver particles 3, 14.83% by mass of ODO, 3.71% by mass of DBDG and 1.46% by mass. % Of IPTL-A was obtained as a bonding material (silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.3 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.9.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 15]
The addition amount of ODO as the solvent 1 was 14.85 g, the addition amount of DBDG as the solvent 2 was 1.65 g, and the addition amounts of ODO and DBDG as the dilution solvent were 1.81 g and 0.20 g, respectively. In the same manner as in Example 11, 60.3% by mass of silver particles 2, 20.1% by mass of silver particles 3, 16.32% by mass of ODO, 1.81% by mass of DBDG and 1.47% by mass. % Of IPTL-A was obtained as a bonding material (silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.7 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.9.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 16]
Except for adding 2.25 g of 1-decanol (manufactured by Wako Pure Chemical Industries, Ltd.) instead of DBDG as solvent 2 and adding 2.19 g of ODO and 2.19 g of 1-decanol instead of ODO and DBDG as diluent solvents. In the same manner as in Example 11, 58.9% by mass of silver particles 2, 19.6% by mass of silver particles 3, 10.03% by mass of ODO, 10.03% by mass of 1-decanol, and 1. A bonding material (silver paste) containing 44% by mass of IPTL-A was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.0 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.3.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 17]
Except that 6.60 g of 1-decanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added instead of DBDG as solvent 2, and 2.30 g of ODO and 1.54 g of 1-decanol were added as dilution solvents instead of ODO and DBDG. In the same manner as in Example 12, 59.2% by mass of silver particles 2, 19.7% by mass of silver particles 3, 11.79% by mass of ODO, 7.86% by mass of 1-decanol and 1. A bonding material (silver paste) containing 45% by mass of IPTL-A was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.4 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.3.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 18]
Except that 4.95 g of 1-decanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added instead of DBDG as solvent 2, and 2.32 g of ODO and 0.99 g of 1-decanol were added instead of ODO and DBDG as solvent. In the same manner as in Example 13, 59.5% by mass of silver particles 2, 19.8% by mass of silver particles 3, 13.47% by mass of ODO, 5.77% by mass of 1-decanol and 1. A bonding material (silver paste) containing 46% by mass of IPTL-A was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.8 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.2.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 19]
Except that 3.30 g of 1-decanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as the solvent 2 instead of DBDG, and 2.23 g of ODO and 0.56 g of 1-decanol were added as the diluent solvent instead of ODO and DBDG. In the same manner as in Example 14, 59.8% by weight of silver particles 2, 19.9% by weight of silver particles 3, 15.07% by weight of ODO, 3.77% by weight of 1-decanol and 1. A bonding material (silver paste) containing 46% by mass of IPTL-A was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.2 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.2.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 20]
1-decanol (manufactured by Wako Pure Chemical Industries, Ltd.) 1.65 g was added instead of DBDG as solvent 2, and ODO 2.05 g and 1-decanol 0.23 g were added instead of ODO and DBDG as diluent solvents. In the same manner as in Example 15, 60.1% by mass of silver particles 2, 20.0% by mass of silver particles 3, 16.59% by mass of ODO, 1.84% by mass of 1-decanol and 1. A bonding material (silver paste) containing 47% by mass of IPTL-A was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.6 mass%.

Was the particle size of silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.1.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 21]
Implementation was performed except that 8.25 g of hexyl diglycol (HeDG) (manufactured by Nippon Emulsifier Co., Ltd.) was added as the solvent 2 instead of DBDG, and 1.99 g of ODO and 1.99 g of HeDG were added as the diluent solvent instead of ODO and DBDG. In the same manner as in Example 11, 59.1% by weight of silver particles 2, 19.7% by weight of silver particles 3, 9.88% by weight of ODO, 9.88% by weight of HeDG and 1.44% by weight of A bonding material (silver paste) containing IPTL-A was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.2 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.1.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 22]
The addition amount of ODO as solvent 1 is 7.50 g, the addition amount of DBDG as solvent 2 is 7.50 g, the addition amount of IPTL-A as an additive is 3.0 g, and ODO and DBDG as dilution solvents Except for the addition amounts of 1.65 g and 1.65 g, respectively, 59.5% by mass of silver particles 2 and 19.8% by mass of silver particles 3 and 8.90% by mass were obtained in the same manner as in Example 11. Of ODO, 8.90% by mass of DBDG and 2.90% by mass of IPTL-A were obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.3 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.1.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 23]
The amount of ODO added as solvent 1 was 8.00 g, the amount of DBDG added as solvent 2 was 8.00 g, the amount of IPTL-A added as an additive was 2.0 g, and the amount of ODO and DBDG as diluent solvents Except for the addition amounts of 1.92 g and 1.92 g, respectively, 59.2% by mass of silver particles 2 and 19.7% by mass of silver particles 3 and 9.59% by mass were obtained in the same manner as in Example 11. Of ODO, 9.59% by mass of DBDG and 1.92% by mass of IPTL-A were obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 78.0 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.2.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 24]
After obtaining a dry powder of an aggregate of silver fine particles (coated with sorbic acid) in the same manner as in Example 9, 72.0 g of the dry powder (silver particle 2) of the aggregate of silver fine particles and a micron size In place of 10.0 g of silver particles AG2-1C (manufactured by DOWA Electronics Co., Ltd., average particle size 0.3 μm) (silver particles 3) with the dry powder (silver particles 1) of the aggregate of silver fine particles of Example 1 The amount of ODO added as solvent 1 was 8.25 g, the amount of DBDG added as solvent 2 was 8.25 g, the amount of IPTL-A added as additive was 1.5 g, and the amount of ODO as diluent solvent was And DBDG were added to 2.75 g and 2.75 g, respectively, and 68.3 mass by the same method as in Example 1 except that oxydiacetic acid (diglycolic acid) as a sintering aid was not added. % Silver particles 2 To give 9.5 wt% silver particles 3 with 10.40 wt% of ODO and 10.40 wt% of DBDG and bonding material containing 1.40 wt% of IPTL-A (the silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 76.5 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 4.4.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Example 25]
2-methyl-butane-1,3,4-triol (isoprenetriol B (IPTL-B)) (boiling point 278-282 ° C., viscosity (25 ° C.) 4050 mPa · s, surface instead of IPTL-A as additive 3.00 g of tension (25 ° C.) 47.5 ± 1.0 dyne / cm (average value 47.5 dyne / cm)) was added, and the addition amounts of ODO and DBDG as dilution solvents were 2.84 g and 0.32 g, respectively. In the same manner as in Example 1, except that 83.4% by mass of silver particles 1, 12.34% by mass of ODO, 1.37% by mass of DBDG, 2.92% by mass of IPTL-B A bonding material (silver paste) containing 0.01% by mass of DGA was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 82.8 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.4.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, no bubbles were observed in the coating film, and cracks and peeling were not observed in the pre-dried film. It was not observed, and no void was observed in the silver bonding layer of the bonded body.

[Comparative Example 1]
According to the same method as in Example 1, except that the amount of ODO added as the solvent 1 was 17.49 g, DBDG as the solvent 2 was not added, and 5.67 g of ODO was added instead of ODO and DBDG as the diluent solvent. A bonding material (silver paste) containing 81.4% by mass of silver particles 1, 15.80% by mass of ODO, 2.79% by mass of IPTL-A, and 0.01% by mass of DGA was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 79.9 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). The Ti value was 3.3.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were produced and observed by the same method as in Example 1. As a result, bubbles were formed in the coating film, and cracks occurred in the pre-dried film. No peeling of the pre-dried film was observed. Further, voids originating from cracks in the pre-dried film were observed in the silver bonding layer of the bonded body.

[Comparative Example 2]
Diol (IPDL-EtHex) (manufactured by Nippon Terpene Chemical Co., Ltd., boiling point 287.8 ° C., viscosity (25 ° C.) 90.2 mPa · s, surface tension (25 ° C.) 30.3 dyne instead of IPTL-A as additive / Cm) 3.0 g was added, and 78.6% by mass of silver was obtained in the same manner as in Example 1 except that the addition amounts of ODO and DBDG as dilution solvents were 8.36 g and 0.93 g, respectively. A bonding material (silver paste) containing particles 1, 16.55% by mass of ODO, 1.84% by mass of DBDG, 2.74% by mass of IPDL-EtHex, and 0.01% by mass of DGA was obtained. In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 77.5 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). And the Ti value was 4.5.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were prepared and observed in the same manner as in Example 1. As a result, bubbles were formed in the coating film, and cracks and peeling occurred in the pre-dried film. However, no peeling of the pre-dried film was observed. Further, voids originating from cracks in the pre-dried film were observed in the silver bonding layer of the bonded body.

[Comparative Example 3]
Diol (IPDL-C8) (manufactured by Nippon Terpene Chemical Co., Ltd., boiling point 308.1 ° C., viscosity (25 ° C.) 65 mPa · s, surface tension (25 ° C.) 30.86 dyne / cm instead of IPTL-A as additive ) 78.9% by mass of silver particles 1 in the same manner as in Example 1 except that 3.0 g was added and the addition amounts of ODO and DBDG as dilution solvents were 8.13 g and 0.90 g, respectively. And 16.28% by mass of ODO, 1.81% by mass of DBDG, 2.75% by mass of IPDL-C8 and 0.01% by mass of DGA were obtained (silver paste). In addition, when Ag concentration in a silver paste was calculated | required with the heat loss method, Ag concentration was 77.5 mass%.

Was the particle size of the silver particles contained in the bonding material (silver paste) was evaluated in the same manner as in Example 1, 1st scratch less than 20 [mu] m, 4th scratch less than 10 [mu] m, the average particle size D ₅₀ was less than 5μm It was. Moreover, when the viscosity and Ti value of this bonding material (silver paste) were determined by the same method as in Example 1, the viscosity was 15 (Pa · s) at 25 rpm and 5 rpm (15.7 [1 / S]). And the Ti value was 4.5.

Using this bonding material, a coating film, a pre-dried film, and a bonded body were prepared and observed in the same manner as in Example 1. As a result, bubbles were formed in the coating film, and cracks and peeling occurred in the pre-dried film. It was. Further, voids originating from cracks in the pre-dried film were observed in the silver bonding layer of the bonded body.

[Comparative Example 4]
Hexadecane (Wako Pure Chemical Industries, Ltd., boiling point 286.6 ± 3.0 ° C., viscosity (25 ° C.) 3 mPa · s, surface tension (25 ° C.) 27.3 ± 3.0 dyne / cm instead of DBDG as solvent 2 (Average value 27.3 dyne / cm), nonpolar) 1.10 g was added and the bonding material (silver paste) was prepared in the same manner as in Example 1 except that ODO and DBDG were not added as dilution solvents. Production was attempted, but separation occurred before addition of ODO and hexadecane as diluent solvents, so that each component could not be produced due to poor dispersion.

Tables 1 and 2 show the manufacturing conditions and characteristics of the bonding materials of these examples and comparative examples.

Claims (17)

1. In a bonding material comprising a silver paste containing silver fine particles, a solvent and an additive, the solvent comprises a first solvent comprising a diol and a second solvent comprising a polar solvent having a surface tension lower than that of the first solvent. The joining material is characterized in that the additive is triol.
2. The bonding material according to claim 1, wherein the first solvent is octanediol.
3. 2. The bonding material according to claim 1, wherein the second solvent is at least one selected from the group consisting of dialkyl glycol ethers, ethylene glycol ethers, and monoalcohols.
4. 2. The bonding material according to claim 1, wherein the second solvent is at least one selected from the group consisting of dibutyl diglycol, hexyl diglycol, and decanol.
5. The bonding material according to claim 1, wherein the average primary particle diameter of the silver fine particles is 1 to 100 nm.
6. The bonding material according to claim 1, wherein the content of the silver fine particles in the bonding material is 60 to 90% by mass.
7. 2. The bonding material according to claim 1, wherein the bonding material contains silver particles having an average particle diameter of 0.2 to 10 μm.
8. The content of silver particles having an average particle size of 0.2 to 10 μm in the bonding material is 30% by mass or less, and the content of the silver fine particles and the content of silver particles having the average particle size of 0.2 to 10 μm. The bonding material according to claim 7, characterized in that the total amount of the bonding material is 60 to 90% by mass.
9. The bonding material according to claim 1, wherein the silver fine particles are coated with an organic compound having 8 or less carbon atoms.
10. The bonding material according to claim 9, wherein the organic compound is sorbic acid.
11. The bonding material according to claim 1, wherein the content of the first solvent in the bonding material is 5 to 20% by mass.
12. The bonding material according to claim 1, wherein the content of the second solvent in the bonding material is 0.5 to 15% by mass.
13. The bonding material according to claim 1, wherein the content of the additive in the bonding material is 0.5 to 10% by mass.
14. The bonding material according to claim 1, wherein the bonding material includes a sintering aid.
15. The bonding material according to claim 14, wherein the sintering aid is diglycolic acid or malonic acid.
16. The bonding material according to claim 14, wherein the content of the sintering aid in the bonding material is 0.001 to 0.1 mass%.
17. The bonding material according to claim 1 is interposed between the objects to be bonded and heated to sinter the silver in the bonding material to form a silver bonding layer, and the objects to be bonded are bonded to each other by the silver bonding layer. The joining method characterized by the above-mentioned.