JP5821743B2 - Conductive composition and method for producing joined body - Google Patents

Description

  The present invention relates to a conductive composition for forming a conductive fired portion made of a fired body having conductivity, and a method of manufacturing a joined body using the conductive composition.

Examples of semiconductor devices in which electronic components such as semiconductor elements are mounted on a circuit include LEDs and power modules.
Here, when an electronic component such as a semiconductor element is joined on a circuit, a method using a solder material is widely used as disclosed in Patent Document 1, for example. Recently, lead-free solders such as Sn—Ag, Sn—In, or Sn—Ag—Cu are becoming mainstream from the viewpoint of environmental protection.

In addition, as an alternative to the solder material, Patent Documents 2 and 3 disclose a technique for joining an electronic component such as a semiconductor element on a circuit using an oxide paste containing metal oxide particles and a reducing agent made of an organic substance. Has been proposed.
In an oxide paste containing metal oxide particles and an organic reducing agent, the metal particles produced by the reduction of the metal oxide particles by the reducing agent are sintered to form a conductive fired body. A bonding layer (conductive fired portion) is formed, and an electronic component such as a semiconductor element is bonded onto the circuit through this bonding layer.

JP 2004-172378 A JP 2008-208442 A JP 2009-267374 A

By the way, as described in Patent Documents 2 and 3, when an oxide paste containing metal oxide particles and a reducing agent made of an organic material is used, the metal oxide particles are reduced by the reducing agent. Although the particle size of the generated metal particles is small and the fired body itself has a dense structure, there is a possibility that a relatively large void may be generated inside the bonding layer (conductive fired portion).
In recent years, in particular, semiconductor devices have been reduced in size and thickness, and the usage environment has become stricter, and there has been a demand for improved bonding reliability between semiconductor elements and electronic components.

  The present invention has been made in view of the above-described circumstances, and is composed of a fired body having a dense structure, and a conductive composition capable of forming a conductive fired part in which generation of large voids is suppressed inside, and An object of the present invention is to provide a method for producing a joined body using the conductive composition.

In order to solve such problems and achieve the above-mentioned object, the conductive composition of the present invention is a conductive composition for forming a conductive fired part having conductivity, comprising silver oxide and A reducing agent, metal Ag particles, fine Ag particles having a volume mode diameter of 20 nm to 800 nm and a solvent, and the metal Ag particles have a volume mode diameter of more than 0.8 μm and 20 μm or less. being, the mass ratio between the mass [Ag] of the mass of silver oxide [Ag-O] and the metal Ag particles [Ag-O] / [Ag] is, 50/50 ≦ [Ag- O] / [ Ag] ≦ 99/1.

According to this conductive composition, since it contains silver oxide and a reducing agent, the silver oxide is reduced at the time of firing, and fine silver particles (reduced silver particles) are generated. A fired body can be obtained. Furthermore, since the conductive composition contains metal Ag particles having a volume mode diameter of more than 0.8 μm and not more than 20 μm, it is possible to suppress the formation of large voids inside the conductive fired portion made of the fired body. can do.
In addition, when [Ag-O] / [Ag] exceeds 99/1, since there are too few metal Ag particle | grains, there exists a possibility that many voids may generate | occur | produce in the inside of the electroconductive baking part which consists of a baking body. is there. On the other hand, when [Ag-O] / [Ag] is less than 50/50, the calorific value due to the reduction of silver oxide is insufficient, and sintering may be insufficient. Therefore, the mass ratio [Ag-O] / [Ag] between the silver oxide and the metal Ag particles is set within the range of 50/50 ≦ [Ag-O] / [Ag] ≦ 99/1. .
In addition, since the fine Ag particles having a volume mode diameter of 20 nm to 800 nm are filled, and the fine Ag particles are filled in the gaps between the metal Ag particles, the proportion of the space of the Ag particles increases, and the dense A conductive fired part having a simple structure can be obtained.

Here, the mass ratio [Ag—O] / [R] of the weight [Ag—O] of the silver oxide and the weight [R] of the reducing agent is 3/1 ≦ [Ag—O] / [R]. It is preferable to be within a range of ≦ 12/1.
In this case, since the necessary reducing agent for the silver oxide is secured, the silver oxide can be reliably reduced, and the reducing agent is not added excessively. It can suppress that a reducing agent component remains inside.

The mass ratio [Ag] / [SAg] of the mass [Ag] of the metal Ag particles and the mass [SAg] of the fine Ag particles satisfies 1/1 ≦ [Ag] / [SAg] ≦ 4/1. It may be within the range .

Furthermore, the silver oxide is 10% by mass to 80% by mass, the reducing agent is 1% by mass to 10% by mass, the metal Ag particles are 0.1% by mass to 45% by mass, and the resin is 0% by mass or more. It is preferable to contain in the range of 2 mass% or less, and the remainder to be a solvent.
Since the silver oxide is 10% by mass or more and 80% by mass or less and the reducing agent is 1% by mass or more and 10% by mass or less, the silver oxide is surely reduced by the reducing agent to obtain a sintered body having a dense structure. be able to. Moreover, since metal Ag particle | grains are 0.1 mass% or more and 45 mass% or less, it is possible to suppress that a comparatively big space | gap arises in the electroconductive baking part which consists of a sintered body. Furthermore, when it contains fine Ag particles, the content is desirably 15% by mass or less. In this case, the conductive fired portion made of the fired body can be further densified.
The resin adjusts the viscosity of the conductive composition, and may be added as necessary in consideration of handleability.

  The method for manufacturing a joined body according to the present invention is a method for producing a joined body in which a first member and a second member are joined, and the conductive material described above is interposed between the first member and the second member. Heat treatment is performed with the composition interposed, and the first member and the second member are joined through a joining layer made of a fired body of the conductive composition.

  According to the method for producing a bonded body having this structure, a fine structure is formed by reduced silver particles generated by reduction of silver oxide, and a large void is generated inside by metal Ag particles of more than 0.8 μm and not more than 20 μm. It can be set as the joining layer (electroconductive baking part) of the structure where it was suppressed. The first member and the second member are bonded through such a bonding layer (conductive fired portion), and it becomes possible to manufacture a bonded body having excellent bonding reliability.

  According to the present invention, a conductive composition that is formed of a fired body having a dense structure and is capable of forming a conductive fired part in which generation of large voids is suppressed, and a joined body using the conductive composition The manufacturing method of can be provided.

It is a flowchart which shows the manufacturing method of the electroconductive composition which is embodiment of this invention. It is a flowchart which shows the manufacturing method of the conjugate | zygote which is embodiment of this invention. It is explanatory drawing of the manufacturing method of the conjugate | zygote shown in FIG.

  Below, the conductive composition which is embodiment of this invention and the manufacturing method of the conjugate | zygote using this conductive composition are demonstrated with reference to attached drawing.

The conductive composition according to the reference embodiment contains silver oxide, a reducing agent, a solvent, a resin, and metal Ag particles having a volume mode diameter of more than 0.8 μm and not more than 20 μm. The mass ratio [Ag-O] / [Ag] of the weight [Ag-O] of silver and the weight [Ag] of metal Ag particles is 50 / 50≤ [Ag-O] / [Ag] ≤99 / 1. It is set within the range. The mass ratio [Ag-O] / [R] of the weight [Ag-O] of the silver oxide and the weight [R] of the reducing agent is within the range of 3/1 ≦ Ag—O / R ≦ 12/1. Is set to

A specific composition is 10% by mass or more and 80% by mass or less of silver oxide, 1% by mass or more and 10% by mass or less of a reducing agent, and 0.1% by mass or more of metal Ag particles of 0.8 μm or more and 20 μm or less. The resin is contained in a range of 0% by mass or less and 0% by mass or more and 2% by mass or less with the balance being a solvent.
The conductive composition in the present embodiment has a viscosity adjusted to 10 Pa · s to 400 Pa · s, more preferably 30 Pa · s to 300 Pa · s.

  As the silver oxide, a powder (silver oxide powder) having an average particle diameter of 0.1 μm or more and 40 μm or less was used. The silver oxide powder is dispersed as silver oxide in the silver paste. Such silver oxide powder is available as a commercial product.

The reducing agent is an organic substance having reducibility, and for example, alcohol and organic acid can be used.
If it is an alcohol, for example, methanol, ethanol, propanol, butyl alcohol, pentyl alcohol, hexyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, etc. The primary alcohol can be used. In addition to these, compounds having a large number of alcohol groups may be used.
If it is an organic acid, for example, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, Saturated fatty acids such as octadecanoic acid and nonanedecanoic acid can be used. In addition to these, unsaturated fatty acids may be used.
Note that it is preferable to use an organic substance having a molecular structure excellent in thermal decomposability in order to suppress generation of voids due to residual impurities in the fired body obtained by sintering the conductive composition.

  In addition, if it is a reducing agent in which a reductive reaction does not advance easily after mixing with silver oxide, the storage stability of an electroconductive composition will improve. Therefore, as the reducing agent, those having a melting point of room temperature or higher are preferable, and specifically, myristyl alcohol, 1-dodecanol, 2,5-dimethyl-2,5-hexanediol, 2,2-dimethyl-1,3. It is preferable to use propanediol, 1,6-hexanediol, 1,2,6-hexanetriol, 1,10-decanediol, myristic acid, decanoic acid and the like.

It is preferable to use a solvent having a high boiling point (150 ° C. to 300 ° C.) from the viewpoint of ensuring the storage stability and printability of the conductive composition.
Specifically, α-terpineol, 2-ethylhexyl acetate, 3-methylbutyl acetate, or the like can be used.

The resin is added for the purpose of improving the handleability (for example, printability) of the conductive composition.
For example, an acrylic resin, a cellulose resin, or the like can be applied. In the present embodiment, an acrylic resin having good thermal decomposability is used in order to prevent the resin from being completely oxidized and decomposed at a temperature equal to or lower than the sintering temperature and not remaining in the conductive fired portion.

As the metal Ag particles in the reference embodiment , metal Ag powder having a volume mode diameter exceeding 0.8 μm and not more than 20 μm and an average particle diameter of 5 μm was used. The metal Ag powder is dispersed as metal Ag particles in the conductive composition. The particle diameter of the metal Ag powder (metal Ag particles) was photographed at a magnification of about 5000 times with a SEM (scanning electron microscope), and the primary particle diameter of 200 particles of metal Ag particles was measured from the obtained image. The particle size distribution is created, and the volume mode value obtained from the created particle size distribution is calculated as the volume mode diameter.
The shape of the metal Ag powder (metal Ag particles) is not particularly limited, and may be spherical or flat.

  The metal Ag powder (metal Ag particles) having a volume mode diameter of more than 0.8 μm and not more than 20 μm is contained in the conductive composition in order to suppress the formation of large voids in the conductive fired part. Since the reduced silver particles obtained by reducing silver oxide are fine, the reduced silver particles agglomerate and the fired body itself has a dense structure, but a relatively large void is generated inside the conductive fired part. There is. In this embodiment, since the conductive composition contains metal Ag particles having a volume mode diameter of more than 0.8 μm and not more than 20 μm, the generation of relatively large voids as described above is suppressed. When the volume mode diameter of the metal Ag particles is 0.8 μm or less, the effect of suppressing the generation of large voids inside the conductive fired portion cannot be obtained. On the other hand, when the thickness exceeds 20 μm, it is difficult to uniformly disperse the metal Ag particles at the time of applying the silver oxide paste.

  Furthermore, in this embodiment, the mass ratio [Ag-O] / [Ag] of the weight [Ag-O] of silver oxide and the weight Ag of the metal Ag particles is 50/50 ≦ [Ag-O] / [ Ag] ≦ 99/1. The reason for the above range is that when [Ag-O] / [Ag] is smaller than 50/50, the amount of silver oxide is too small, so that there is a shortage of fine reduced silver particles produced by reduction, and the desired conductivity. This is because the strength cannot be obtained. Moreover, since it is too few metal Ag particle | grains when larger than 99/1, it is because the inhibitory effect with respect to the space | gap generation | occurrence | production inside an electroconductive baking part is not acquired.

Next, the manufacturing method of the electroconductive composition which is this embodiment is demonstrated with reference to the flowchart shown in FIG.
In this embodiment, it is set as the structure which manufactures the electrically conductive composition which is this embodiment by mixing and stirring the silver oxide paste containing silver oxide, and Ag paste containing a metal Ag particle. Yes.

First, the above-described silver oxide powder and reducing agent (solid powder) are mixed to produce a solid component mixture (powder mixing step S01).
Moreover, resin and a solvent are mixed and an organic mixture is produced | generated (organic substance mixing process S02).

The solid component mixture obtained in the powder mixing step S01 and the organic mixture obtained in the organic matter mixing step S02 are mixed and stirred (first stirring step S03). And the stirring thing obtained by 1st stirring process S03 is mixed, for example using a roll mill machine which has a some roll, kneading (kneading process S04).
In this way, the aforementioned silver oxide paste is produced. In addition, it is preferable to preserve | save the obtained silver oxide paste at low temperature (for example, 5-15 degreeC) with a refrigerator.

On the other hand, the metal Ag powder and the solvent are mixed and stirred (second stirring step S05). As a result, an Ag paste in which metal Ag powder (metal Ag particles) having a volume mode diameter of greater than 0.8 μm and 20 μm or less is dispersed is produced.
In addition, it is desirable to use the same type of solvent as the solvent used for the silver oxide paste. The composition of the Ag paste is preferably such that the content of metal Ag particles having a volume mode diameter of more than 0.8 μm and not more than 20 μm is 50% by mass or more and 80% by mass or less, and the remainder is a solvent.

Then, the silver oxide paste and the Ag paste are mixed and stirred (paste mixing step S06).
Thus, the electroconductive composition which is this embodiment is manufactured.

Next, the manufacturing method of the joined body which is this embodiment is demonstrated using FIG.2 and FIG.3.
As shown in FIG. 3, the joined body 10 in the present embodiment is formed by joining a first member 11 and a second member 12. The first member 11 is a Si substrate, and the second member 12. Is a sapphire substrate.

  First, the electroconductive composition 20 which is this embodiment is apply | coated to the joint surface of the 1st member 11 (electroconductive composition application | coating process S11). In this conductive composition coating step S11, a screen printing method, an offset printing method, a photosensitive process spray coating method, a dispenser coating method, a spin coating method, a knife coating method, a slit coating method, an ink jet coating method, or a die Various means such as a coating method can be employed. In this embodiment, a screen printing method is used.

Next, the first member 11 and the second member 12 are laminated through the applied conductive composition 20 (lamination step S12).
And it inserts in a heating furnace in the state which laminated | stacked the 1st member 11 and the 2nd member 12, and sinters the electroconductive composition 20 (sintering process S13). At this time, the inside of the heating furnace was an air atmosphere, the heating temperature was 150 ° C. to 300 ° C., and the heating time was 0.5 hours to 2 hours.

By this sintering step S <b> 13, a bonding layer 15 (conductive fired portion) made of a fired body of the conductive composition 20 is formed between the first member 11 and the second member 12. The two members 12 are joined to each other.
Thus, the joined body 10 in which the first member 11 and the second member 12 are joined is manufactured.

  The conductive composition according to the present embodiment having the above-described configuration contains silver oxide and a reducing agent, so that the silver oxide is reduced during firing to produce fine reduced silver particles, and the dense composition. A fired body having a simple structure can be obtained. Further, it contains silver oxide and metal Ag particles having a volume mode diameter of more than 0.8 μm and not more than 20 μm, and the weight of silver oxide [Ag—O] and the weight of metal Ag particles [Ag] Since the mass ratio [Ag-O] / [Ag] is in the range of 50/50 ≦ [Ag-O] / [Ag] ≦ 99/1, the bonding layer 15 (conductive fired portion) is large. It is possible to obtain a bonding layer 15 (conductive fired portion) with less voids and less voids.

  The mass ratio [Ag-O] / [R] of the weight [Ag-O] of the silver oxide and the weight [R] of the reducing agent is 3 / 1≤ [Ag-O] / [R] ≤12 / Since it is within the range of 1, a necessary reducing agent for silver oxide is ensured, and silver oxide can be reliably reduced. Furthermore, since the reducing agent is not added excessively, it can be suppressed that the reducing agent component remains inside the conductive fired portion formed of the formed fired body.

  Further, since the silver oxide is 10% by mass or more and 80% by mass or less and the reducing agent is 1% by mass or more and 10% by mass or less, the silver oxide is surely reduced by the reducing agent, and the sintered body has a dense structure. Can be obtained. Further, since the metal Ag particles are 0.1% by mass or more and 45% by mass or less, it is possible to suppress the generation of large voids in the bonding layer 15 (conductive firing part) made of the fired body. .

  Further, by adjusting the resin content, the viscosity of the conductive composition is adjusted to 10 Pa · s or more and 400 Pa · s or less, more preferably 30 Pa · s or more and 300 Pa · s or less. Can be applied. Therefore, the conductive composition can be selectively applied only to necessary portions, and the amount of the conductive composition used can be reduced.

  Moreover, in this embodiment, since the reducing agent mixed with the conductive composition is a solid that is solid at room temperature, it is possible to prevent the reduction reaction from proceeding before the sintering step S13.

  Moreover, according to the manufacturing method of the joined body 10 of the present embodiment, the conductive composition 20 is applied between the first member 11 and the second member 12, and the conductive composition 20 is sintered and joined. Since the layer 15 is formed, the first member 11 and the second member 12 are firmly bonded to each other by the bonding layer 15 (conductive baking portion) which is made of a densely-baked body and has a small large void inside. can do.

Next, an embodiment of the present invention will be described.
The conductive composition according to the embodiment of the present invention has fine Ag particles having a volume mode diameter different from that of the metal Ag particles in addition to the conductive composition described in the reference embodiment . Specifically, it contains silver oxide, a solvent, a resin, metal Ag particles having a volume mode diameter exceeding 0.8 μm and 20 μm or less, and fine Ag particles having a volume mode diameter of 20 nm to 800 nm. The mass ratio [Ag-O] / [Ag] of the weight [Ag-O] of the silver oxide and the weight [Ag] of the metal Ag particles is 50 / 50≤ [Ag-O] / [Ag] ≤99. / 1 is set. The mass ratio [Ag-O] / [R] of the weight [Ag-O] of the silver oxide and the weight [R] of the reducing agent is 3 / 1≤ [Ag-O] / [R] ≤12 / 1 is set. In such a case, since two types of Ag particles (metal Ag particles and fine Ag particles) having two types of volume mode diameters having different volume mode diameters are used, the particle size of the Ag particles as a whole. The distribution will have two peaks.
In the embodiment of the present invention, the mass ratio [Ag] / [SAg] of the weight [Ag] of the metal Ag particles and the weight [SAg] of the fine Ag particles is 1/1 ≦ [Ag] / [SAg ] ≦ 4/1.

According to the conductive composition of this embodiment of the present invention, it contains metal Ag particles having a volume mode diameter of more than 0.8 μm and not more than 20 μm, and fine Ag particles having a volume mode diameter of not less than 20 nm and not more than 800 nm. Therefore, the fine Ag particles having a relatively small particle size are filled between the metal Ag particles having a relatively large particle size, and the density of the Ag particles after drying of the conductive composition is increased. Therefore, a dense conductive fired part can be obtained even under sintering conditions under a low load.
When the volume mode diameter of the fine Ag particles is less than 20 nm, the volume mode diameter is too small to obtain the effect of improving the compactness due to the inclusion of the fine Ag particles. It is set in the above range.

  Further, the mass ratio [Ag] / [SAg] of the weight [Ag] of the metal Ag particles and the weight [SAg] of the fine Ag particles is set to 1/1 ≦ [Ag] / [SAg] ≦ 4/1. Therefore, even if the conductive fired part is produced under sintering conditions under a low load, it is possible to obtain a conductive fired part in which the generation of voids is suppressed. When [Ag] / [SAg] is less than 1/1, since the ratio of fine Ag particles is too small, the effect of improving the compactness due to the inclusion of fine Ag particles cannot be obtained, and 4/1 When exceeding, since the ratio of the metal Ag particles is too small, the effect of suppressing the generation of relatively large voids inside the conductive fired portion cannot be obtained, so the above range is set.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.

Moreover, although this embodiment demonstrated as what manufactures an electroconductive composition by mixing a silver oxide paste and Ag paste, it is not limited to this, Silver oxide and metal Ag particle | grains are mixed. After that, a solvent or a resin may be mixed.
Furthermore, in this embodiment, although the 1st member was demonstrated as Si board | substrate and the 2nd member was demonstrated as a sapphire substrate, it is not limited to this, There is no limitation in a 1st member and a 2nd member, As mentioned above What is necessary is just to join by the sintered body of an electroconductive composition.
For example, you may apply when joining aluminum members, or joining an aluminum member and a ceramic substrate. Moreover, you may apply when joining a copper member, when joining a copper member and a ceramic substrate, and joining an aluminum member and a copper member.

  In the present embodiment, the conductive fired portion has been described as the bonding layer 15. However, the present invention is not limited to this. For example, the bonding portion may be a bonding portion for fixing the wiring of the electronic component on the substrate. good.

  Moreover, although this embodiment demonstrated the case where the metal Ag particle and fine Ag particle which have different volume mode diameter were contained, it is not limited to two types of Ag particle, Three types which have different volume mode diameters The structure using the above Ag particle | grains may be sufficient.

Below, the result of the confirmation experiment performed in order to confirm the effect of this invention is demonstrated.
A conductive composition was produced by the method described in this embodiment. At this time, as shown in Table 1, the composition of the conductive composition, the volume mode diameter of the metal Ag powder (metal Ag particles), the volume mode diameter of the fine Ag particles, the mass ratio of the silver oxide powder to the metal Ag powder [Ag -O] / [Ag], the mass ratio [Ag] / [SAg] of metal Ag particles and fine Ag particles, and the mass ratio [Ag-O] / [R] of silver oxide powder and reducing agent are changed. A composition was prepared. In Comparative Example 1, a conductive composition containing no metal Ag particles was produced.
Next, a sapphire substrate having a length of 5 mm, a width of 5 mm, and a thickness of 0.2 mm was prepared as an element.
And the electrically conductive composition shown in Table 1 was apply | coated to the surface of Si board | substrate, and the above-mentioned sapphire board | substrate was laminated | stacked. And it sintered on the conditions for 2 hours at 300 degreeC in air | atmosphere, and manufactured the joined body.

As evaluation of the produced joined body, the volume mode diameter and the porosity were measured, and the joining rate was measured. Below, each measuring method is demonstrated.
(Volume mode diameter)
The particle diameter of the metal Ag powder (metal Ag particles) was photographed at a magnification of about 5000 times with a SEM (scanning electron microscope), and the primary particle diameter of 200 particles of metal Ag particles was measured from the obtained image. The particle size distribution is created, and the volume mode value obtained from the created particle size distribution is calculated as the volume mode diameter. The particle diameter was the Heywood diameter represented by the diameter of a circle having the same area as the projected area of the particles (measurement of porosity).
About the obtained joined body, the porosity of the joining layer was measured. The cross section of the bonding layer of the manufactured bonded body was observed using an SEM (scanning electron microscope) to analyze the area of the porosity. (Porosity) = (Area of the void) / (Total of the second fired layer) The porosity was determined by the formula of (area) × 100.
(Measurement of bonding rate)
About the obtained joined body, the porosity of the joining layer was measured. The joining rate was evaluated using an ultrasonic flaw detector and calculated from the following equation. Here, the junction area is defined as an area to be joined before joining, that is, a semiconductor element area. In the ultrasonic flaw detection image, the unbonded portion is indicated by a white portion in the bonded portion, and thus the area of the white portion was defined as the peeled area.
(Joining rate) = {(joined area)-(unjoined area)} / (joined area) × 100

In Reference Example 1 and Invention Example 2 to Invention Example 6 , the particle diameter of the metal Ag powder (metal Ag particles) exceeds 0.8 μm and is 20 μm or less, and the mass ratio [Ag—O] / [Ag] is 50 / Since it is in the range of 50 or more and 99/1 or less, the porosity of the bonding layer was low and good. Particularly, in Invention Example 2 to Invention Example 6, since fine Ag particles were contained in the conductive composition, the porosity of the bonding layer was low and good.
On the other hand, since Comparative Example 1 did not contain metal Ag powder (metal Ag particles), the porosity and bonding rate were low, which was inferior to that of the present invention. Moreover, since the volume mode diameter of the metal Ag powder (metal Ag particles) is too large in Comparative Example 2, the conductive composition cannot be applied uniformly, and the bonding rate is in comparison with the present invention example. inferior. Furthermore, since the volume mode diameter of the metal Ag powder (metal Ag particles) is too small in Comparative Example 3, the effect of suppressing the generation of voids in the bonding layer cannot be obtained, and the porosity is inferior to that of the present invention example. Moreover, since the comparative example 4 had too many mass ratios of metal Ag powder with respect to silver oxide powder, the porosity became high and the joining rate became low, and it was inferior compared with the example of this invention.

DESCRIPTION OF SYMBOLS 10 Joining body 11 First member 12 Second member 15 Joining layer 20 Conductive composition

Claims (5)

A conductive composition for forming a conductive fired part having conductivity,
Silver oxide, a reducing agent, metal Ag particles, fine Ag particles having a volume mode diameter of 20 nm or more and 800 nm or less, and a solvent,
The metal Ag particles have a volume mode diameter of more than 0.8 μm and not more than 20 μm,
The mass ratio between the mass [Ag] of the mass of silver oxide [Ag-O] and the metal Ag particles [Ag-O] / [Ag] is, 50/50 ≦ [Ag- O] / [Ag] ≦ 99 A conductive composition characterized by being in the range of / 1. The mass ratio [Ag—O] / [R] of the mass [Ag—O] of the silver oxide and the mass [R] of the reducing agent is 3/1 ≦ [Ag—O] / [R] ≦ 12 / The conductive composition according to claim 1, wherein the conductive composition is within a range of 1. The mass ratio [Ag] / [SAg] of the mass [Ag] of the metal Ag particles and the mass [SAg] of the fine Ag particles is within a range of 1/1 ≦ [Ag] / [SAg] ≦ 4/1. the conductive composition according to claim 1 or claim 2, characterized in that there is a.   The silver oxide is 10% by mass to 80% by mass, the reducing agent is 1% by mass to 10% by mass, the metal Ag particles are 0.1% by mass to 45% by mass, and the resin is 0% by mass to 2% by mass. The conductive composition according to claim 1, wherein the conductive composition is contained in a range of at most% and the remainder is a solvent. A method for producing a joined body in which a first member and a second member are joined,
A heat treatment is performed with the conductive composition according to any one of claims 1 to 4 interposed between the first member and the second member, and the first member and the second member A method for producing a joined body, comprising joining a second member via a joining layer made of a fired body of the conductive composition.

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