JP2012142438A - Paste for mounting semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paste for mounting a semiconductor device which has a uniform particle size and exhibits excellent dispersibility to resins.SOLUTION: The paste for mounting a semiconductor device is composed of polyorganosiloxane particles having an average particle size in the range of 0.5-30 μm, a particle size variation coefficient (CV value) of 3% or less, and a content in the range of 30-90 wt%, and one or more than one kind selected from epoxy resin, polyimide resin, bismaleimide resin, acrylic resin, methacryl resin, silicon resin, BT resin, and cyanate resin.

Description

  The present invention relates to a paste for mounting a semiconductor device comprising polyorganosiloxane particles having a uniform particle diameter and a resin.

  In a semiconductor device, an adhesive (sometimes referred to as die attach) is used to bond a substrate and a semiconductor element (chip). At this time, as the adhesive, a resin paste for a semiconductor in which an insulating inorganic filler such as silica or alumina is blended with a resin or a conductive inorganic filler such as silver powder or copper powder is blended is used. . (Patent Document 1: JP-A-11-61086)

In a semiconductor device, a semiconductor chip is mounted on a substrate, but the substrate and the semiconductor chip generally have different linear expansion coefficients. The substrate is made of a material containing an organic resin and has a larger linear expansion coefficient than that of the semiconductor chip. For this reason, when a semiconductor device having a structure in which a semiconductor chip is mounted on a substrate is subjected to a thermal history, the substrate warps due to a difference in linear expansion coefficient between the two. In the conventional semiconductor device, due to the occurrence of the warp, damage such as cracks may occur in the semiconductor chip, the interface between the semiconductor chip and the bump, the interface between the bump and the substrate, or the like.
In addition to this, if the package having the semiconductor chip mounted on the substrate is warped, it becomes difficult to mount the package on the substrate as well as the occurrence of damage as described above. Therefore, it is required to suppress the warpage of the package.

In addition, when a semiconductor chip is mounted face-down on a substrate, a gap is formed between the substrate and the chip. Therefore, it is necessary to fill the gap with an insulating material called an underfill. Conventionally, thermosetting resins such as epoxy resins have been widely used as underfill materials. (Patent Document 2: Japanese Patent Laid-Open No. 11-233571)

  At this time, in order to reduce the coefficient of linear expansion of the underfill and effectively reduce the damage described above, the underfill resin composition contains an inorganic filler such as silica particles previously treated with a coupling agent. It has been proposed. (WO 2006/098219 gazette: Patent Document 3)

In WO2002 / 026626 (Patent Document 4), non-porous spherical silica particles are used as underfill fillers, which are excellent in fluidity at the time of resin mixing, and have low viscosity and low thixotropic underfill. The use of a material and a method for producing non-porous spherical silica particles have been proposed.
The non-porous spherical silica particles at this time have an average particle size of 0.1 to 20 μm and a maximum particle size of 4 times or less of the average particle size, for example, an average particle size of 1.3 μm and a maximum particle size of 3 μm. Silica particles are disclosed. However, in order to make the particle size distribution uniform, it was necessary to crush or classify using a screen and to remove coarse particles.

  However, in recent years, with the high integration of semiconductor substrates, high purity, uniform particle size, production reproducibility, and excellent economic efficiency, when used for underfill materials, die attach sealing materials, etc. In addition, there is a need for an inorganic filler that is excellent in dispersibility and fluidity in a resin, can be reduced in viscosity, has dilatancy properties, and can suppress the occurrence of damage or the like.

Various methods for producing silica particles are known, and a method using a hydrolyzable organosilicon compound is known as high-purity silica particles.
For example, JP-A-7-140472 (Patent Document 5)
R ¹ _m Si (OR ² ) _4-m
(R ¹ and R ² in the formula each represent a specific organic group. M is an integer of 0 to ^3. )
A spacer for a liquid crystal cell having a specific compression modulus is obtained by subjecting the particles obtained by hydrolysis and condensation polymerization of the organosilicon compound represented by formula (I) to heat treatment by changing the temperature in the range of 100 to 1000 ° C. It is disclosed that particles are obtained.

The present inventors have disclosed a method for producing organopolysiloxane fine particles using a specific organosilicon compound in Japanese Patent Application Laid-Open No. 9-59384 (Patent Document 6).
However, in the above method, depending on the type of organosilicon compound, hydrolysis / condensation polymerization may not be complete, or hydrolysis / polycondensation is slow. In some cases, the reproducibility of the particle size was insufficient.

In addition, in the conventional particle production method, it is difficult to adjust the particle size with high accuracy, and in order to obtain particles having uniform physical properties, it is necessary to reduce the production scale or strictly manage the production conditions. there were.
Furthermore, even when the manufacturing scale is reduced, there are cases in which variations among manufacturing batches become a problem.

Further, the applicant of the present application prepares silica particles having a uniform average particle diameter as core particles, hydrophobizes them, and then forms a polyorgano which forms a coating layer having elasticity derived from an organosilicon compound in the presence of a surfactant. A method for producing siloxane-coated elastic fine particles is proposed. (JP 2000-204168, JP 2000-212422: Patent Documents 7 and 8)
However, it takes a long time to obtain silica core particles having a large particle size as the core particles, and further, since an elastic coating layer is formed, there are difficulties in productivity and economy. Furthermore, a gel-like substance was generated and needed to be removed.

Nagao et al., When preparing silica particles by hydrolyzing tetraorthosilicate, when hydrolyzed in the presence of electrolytes such as Kcl and Licl, the particle growth rate is high, and the formation of new particles is suppressed. It has been reported that monodispersed particles having a particle size of about 1 μm can be obtained and the particle size distribution can be adjusted. (Non-patent document 1: D. Nagao et al., J. Chem Eng., Japan 33,468 (2000))
However, there has been a problem that the particle diameter varies from production to production.

  As a result of diligent studies in view of such circumstances, the hydrolyzable organosilicon compound phase is disposed in the upper layer, and the water / carbon monovalent alcohol mixed solvent phase of 5 to 10 carbon atoms is disposed in the lower layer. When prepared, polyorganosiloxane particles having a uniform particle size in a very short time and without coarse particles can be obtained, and when the alcohol is prepared by mixing a monovalent alcohol having 1 to 4 carbon atoms. Polyorganosiloxane particles having a desired particle size can be obtained with good reproducibility. When the polyorganosiloxane particles thus obtained are blended with a resin, the particles have excellent dispersibility in the resin, and the resulting paste has a low viscosity. As a result, the present invention was completed.

JP-A-11-61086 JP-A-11-233571 WO 2006/098219 WO2002 / 026626 Japanese Patent Laid-Open No. 7-140472 JP-A-9-59384 JP 2000-204168 A JP 2000-212422 A

D. Nagao et al., J. Chem Eng., Japan 33,468 (2000)

  An object of the present invention is to provide a paste for mounting a semiconductor device comprising a polyorganosiloxane particle having a uniform particle diameter and excellent dispersibility in a resin and a resin.

The paste for mounting a semiconductor device according to the present invention comprises polyorganosiloxane particles having an average particle diameter in the range of 0.5 to 30 μm and a particle diameter variation coefficient (CV value) of 3% or less and a resin. It is characterized by that.
The content of the polyorganosiloxane particles is preferably in the range of 30 to 90% by weight.
The resin is one or more selected from an epoxy resin, a polyimide resin, a bismaleimide resin, an acrylic resin, a methacrylic resin, a silicone resin, a BT resin, and a cyanate resin. It is preferable.
The paste for mounting the semiconductor device preferably has a viscosity (η ₁ ) in the range of ₁ to 800 Pa · s when the rotation speed of the E-type viscometer is 0.5 rpm. The viscosity (η ₂ ) at several 2.5 rpm is preferably in the range of 1 to 800 Pa · s.
The viscosity (eta ₁₎ and the viscosity ratio of the viscosity _{(η 2) (η 1)} / (η 2) is preferably in the range of from 0.001 to 8.

According to the present invention, it is possible to provide a semiconductor device mounting paste comprising polyorganosiloxane particles having a uniform particle diameter and a resin, and a semiconductor device using the semiconductor device mounting paste.
In addition, it provides a resin paste for underfill with a uniform particle size, excellent dispersibility in resin, low viscosity, excellent fluidity and reflowability, and excellent filling properties between the substrate and the chip. can do.

In addition, it has a uniform particle size, excellent dispersibility in resin, low viscosity, excellent coatability, thixotropy (low reflow property), and effective substrate and semiconductor element (chip) It is possible to provide a resin paste for die attachment that can be adhered to the substrate.
Here, the xotropic property means a phenomenon in which the viscosity gradually decreases to become liquid when subjected to shear stress, and the viscosity gradually increases to finally become solid when stationary.

It is sectional drawing which shows the outline | summary of a semiconductor device.

[Semiconductor device mounting paste]
First, a paste for mounting a semiconductor device according to the present invention will be described.
The paste for mounting a semiconductor device according to the present invention comprises polyorganosiloxane particles having an average particle diameter in the range of 0.5 to 30 μm and a particle diameter variation coefficient (CV value) of 3% or less and a resin. It is characterized by that.

Polyorganosiloxane particles used in the polyorganosiloxane particles present invention the average particle size is 0.5 to 30 m, more preferably in the range of 1 to 20 [mu] m.
When the average particle diameter of the polyorganosiloxane particles is less than 0.5 μm, the viscosity may be high when the content of the polyorganosiloxane particles in the paste is high. In addition, dispersibility may be insufficient, and when used as an object of the present invention, particularly as an underfill filler, the permeability may be insufficient.
If the average particle diameter of the polyorganosiloxane particles exceeds 30 μm, the gap formed by the bumps may not be filled, or even if it can, the permeability may be insufficient.

  When the average particle diameter of the polyorganosiloxane particles is within the above range, a paste for mounting a semiconductor device having a low viscosity, a low thixotropic property and excellent permeability can be obtained. In addition, although selection of an average particle diameter is suitably selected by the magnitude | size of a clearance gap, etc., the manufacturing method of the polyorganosiloxane particle | grains used for this invention mentioned later can manufacture the particle | grains of a desired particle diameter.

The average particle diameter (D _n ) of the polyorganosiloxane particles was photographed with a scanning electron microscope (JEOL Ltd .: JSM-5300 type), and an image analyzer (Asahi Kasei ( Co., Ltd .: IP-1000).

The particle diameter variation coefficient (CV value) is preferably 3% or less, more preferably 2% or less.
When the particle diameter variation coefficient (CV value) is 3% or less, a semiconductor device mounting paste having low viscosity, low thixotropy, and excellent permeability can be obtained.
If the particle diameter variation coefficient (CV value) exceeds 3%, depending on the particle diameter of the polyorganosiloxane particles, the permeability may be insufficient when the gap is small.

The CV value is calculated by the following formula (1).
CV value = (particle diameter standard deviation (σ ₁ ) / average particle diameter (D _n )) × 100 (1)
Particle diameter standard deviation (σ ₁ ) = Σ ⁿ | D _i −D _n | / (n−1) × D _n
D _i : particle diameter of individual particles, n: 250

The content of the polyorganosiloxane particles in the paste for mounting a semiconductor device is preferably 30 to 90% by weight, more preferably 40 to 80% by weight.
When the content of polyorganosiloxane particles is less than 30% by weight, the number of particles is so small that the expansion coefficient is not much different from that of resin alone, cracks may occur around the bumps, and the substrate is warped. Or the semiconductor element may be damaged.
When the content of the polyorganosiloxane particles exceeds 90% by weight, the amount of the resin is decreased, so that the viscosity may be increased. Further, the dispersibility becomes insufficient, and when used for the purpose of the present invention, particularly as an underfill filler, the permeability may be insufficient.

The method for producing the polyorganosiloxane particles used in the present invention is not particularly limited as long as the polyorganosiloxane particles having the average particle diameter and the particle diameter variation coefficient can be obtained. It is recommended because polyorganosiloxane particles having a particle size variation coefficient can be obtained and can be produced in a short time with good reproducibility.
Hereinafter, the manufacturing method of the polyorganosiloxane particle | grains used suitably for this invention is demonstrated.

[Production method of polyorganosiloxane particles]
The method for producing polyorganosiloxane particles used in the present invention comprises a hydrolyzable organosilicon compound phase represented by the following formula (2) as an upper layer, and a water / alcohol mixed solvent phase of a hydrolysis catalyst as a lower layer. In the method for producing polyorganosiloxane particles, wherein the alcohol is a monohydric alcohol (ROH ₁ ) having 5 to 10 carbon atoms and / or the hydrolyzable organosilicon compound and the hydrolysis catalyst are brought into contact with each other. monohydric 1 to 4 carbon atoms alcohol - it is characterized by comprising a Le (ROH _2).
R ¹ _n Si (OR ₂ ) _4-n (2)
(In the formula, R ¹ represents a hydrocarbon group having 1 to 10 carbon atoms selected from a substituted or unsubstituted hydrocarbon group, and R ² represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or 2 to 5 carbon atoms. And n is a positive number of 0 to 3)

Hydrolyzable organosilicon compounds Hydrolyzable organosilicon compounds used in the present invention include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, and diphenyl. Dimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, isobutyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (βmethoxyethoxy) silane, 3,3, 3-trifluoropropyltrimethoxysilane, methyl-3,3,3-trifluoropropyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-g Lysidoxymethyltrimethoxysilane, γ-glycidoxymethyltrioxysilane, γ-glycidoxyethyltrimethoxysilane, γ-glycidoxyethyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycyl Sidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, γ- (β-glycidoxyethoxy) propyltrimethoxysilane, γ- (meth) acrylooxy Methyltrimethoxysilane, γ- (meth) acrylooxymethyltrioxysilane, γ- (meth) acrylooxyethyltrimethoxysilane, γ- (meth) acrylooxyethyltriethoxysilane, γ- (meth) acryl Roxypropyltrimethoxysilane, γ- (meth) acrylo Xylpropyltriethoxysilane, butyltrimethoxysilane, isobutyltriethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, decyltriethoxysilane, butyltriethoxysilane, 3-ureidoisopropylpropyltriethoxysilane, perfluorooctylethyl Trimethoxysilane, perfluorooctylethyltriethoxysilane, perfluorooctylethyltriisopropoxysilane, trifluoropropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, N-β (amino Ethyl) γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, trimethylsilanol Methyl trichlorosilane, dimethoxy dimethyl silane, diethoxy-3-glycidoxypropyl methyl silane, dimethoxy diphenyl silane, diacetoxy dimethyl silane, trimethyl methoxy silane, trimethyl ethoxy silane, trimethyl silanol - le, and the like.

The hydrolyzable organosilicon compound is preferably a hydrolyzable organosilicon compound in which n is 1 in formula (2). When a hydrolyzable organosilicon compound having n of 1 is used, the hydrolysis rate is high, and large polyorganosiloxane particles having a large particle size and a uniform particle size can be obtained in a short time.
The resulting polyorganosiloxane particles do not have fine powder on the surface like fused spherical silica. In addition, there is no need for a new surface treatment with a silane coupling agent. A paste can be obtained.

In addition, the hydrolyzable organosilicon compound may be a mixture of hydrolyzable organosilicon compounds in which n is 0 and 1 in the formula (2). When the mixture is used, polyorganosiloxane particles having a relatively high compression modulus can be obtained.

Hydrolyzable organosilicon compound at this time (n = 0) the number of moles of (M ₀₎ and the hydrolyzable organosilicon compound the number of moles of _{(n = 1) (M 1} ) and the molar ratio of (M ₀₎ / ( M ₁ ) is preferably in the range of 0.01 to 0.5, more preferably 0.02 to 0.4.
When the molar ratio (M ₀ ) / (M ₁ ) is less than 0.01, the effect of mixing and using the hydrolyzable organosilicon compound (n = 0), for example, particles having high particle strength cannot be obtained. There is a case.
When the molar ratio (M ₀ ) / (M ₁ ) exceeds 0.5, the highly reactive hydrolyzable organosilicon compound (n = 0) is hydrolyzed and the hydrolyzable organosilicon compound (n = 1) In some cases, it is difficult to control the particle size because the true spherical particles cannot be obtained.

The catalyst for hydrolysis is not particularly limited as long as it can hydrolyze the hydrolyzable organosilicon compound, and examples thereof include an aqueous alkali metal solution, an aqueous amine solution, an aqueous ammonia solution, and ammonia gas. Among these, an aqueous ammonia solution and ammonia gas are preferable because they do not remain in the particles after drying, which will be described later, and are inexpensive.

Alcohol - Le alcohol - used singly or mixed to Le (ROH ₂₎ - Le (ROH ₁₎ with monohydric 1 to 4 carbon atoms alcohol - monovalent 5 to 10 carbon atoms Arco as Le.
Specifically, as monovalent alcohol (ROH ₁ ) having 5 to 10 carbon atoms, 1-pentanol, 3-methyl-1-butanol, 2-methyl-1-butanol, 2 , 2dimethyl-1-propanol, 2-pentanol, 3-methyl-2-butanol, 3-pentanol, 2-methyl-2-butanol, hexaanol, heptanol, Octanol, nonanol, decanol and the like can be mentioned. These alcohols can be mixed and used as necessary.
The Le (ROH _2), methanol - - 1 to 4 carbon atoms monohydric alcohol, ethanol - Le, 1-propanol - le, isopropanol - Le, 1-butanol - methylphenol, 2-methyl-1-propanol - And 2-butanol, 2-methyl-2-propanol, and the like, and mixtures thereof.

If the carbon number of the alcohol is 11 or more, the solubility in water is low and micelle formation does not occur, which may cause gelation or the like, and desired particles may not be obtained.
When monovalent alcohol (ROH ₁ ) having 5 to 10 carbon atoms is used, polyorganosiloxane particles having a large average particle size and a small particle size variation coefficient (CV value) can be obtained.
The average particle size at this time varies depending on the type of alcohol, but is approximately 5 μm or more, the CV value is 3% or less, and the required time is approximately 2 hours or less.

The monovalent alcohol (ROH ₂ ) having 1 to 4 carbon atoms may have an average particle size of approximately 3 μm or less, although the hydrolyzable organosilicon compound has a high hydrolysis rate, but the average particle size is 0.5 μm or more. If the CV value is 3% or less, it is suitable for the present application. The required time is approximately one hour.
In the present invention, a monovalent alcohol is used, but a polyvalent alcohol can be mixed and used as necessary.

In the above, alcohol (ROH ₁ ) and alcohol (ROH ₂ ) are mixed and used, and the average particle diameter of the polyorganosiloxane particles obtained can be easily adjusted by adjusting the mixing ratio. . On the other hand, in order to adjust the particle diameter when only one of the alcohols is used, the average is only obtained under any one of the conditions such as solid content concentration, temperature, stirring speed, pH at the time of hydrolysis described later. It is difficult to adjust the particle size, and it is difficult to accurately obtain polyorganosiloxane particles having a desired average particle size. In addition, there is a problem that variation in the average particle size for each production becomes large. is there.

Next, the manufacturing method will be specifically described.
First, a mixed solvent of alcohol and water is prepared. The concentration of the alcohol in the mixed solvent is preferably in the range of 0.1 to 20% by weight, more preferably 0.2 to 10% by weight.
If the alcohol concentration in the mixed solvent is less than 0.1% by weight, the resulting particles tend to be smaller because the formation of uniform and large micelles does not occur, and the hydrolysis reaction time tends to be longer. There is.
If the alcohol concentration in the mixed solvent exceeds 20% by weight, the hydrolysis reaction time is shortened, but control is difficult, and the uniformity and reproducibility of the particle diameter may be insufficient. Depending on the type, the separation of the upper layer of the hydrolyzable organosilicon compound and the lower layer of the alcohol / water may be incomplete, and in this case, the uniformity and reproducibility of the particle size may be insufficient. Depending on the desired particle size, alcohol (ROH ₁ ) and alcohol (ROH ₂ ) can be mixed and used.

Next, the aforementioned organosilicon compound is added. At this time, the organosilicon compound is added without stirring or under gentle stirring so that the organic silicon compound is separated into the upper layer and the mixed solvent is separated into the lower layer.
The addition amount of the organosilicon compound is such that the concentration of the organosilicon compound in the total of the mixed solvent and the organosilicon compound is a solid content (R ¹ _n SiO _{2 / 4-n} or SiO ₂ + R ¹ _n SiO _{2 / 4-n} ). It is preferably in the range of 0.5 to 15% by weight, more preferably 1 to 10% by weight.

When the concentration of the organosilicon compound is less than 0.5% by weight as the solid content, the particle diameter of the resulting polyorganosiloxane particles may be too small, and there is a problem that productivity is lowered.
When the concentration of the organosilicon compound exceeds 15% by weight as a solid content, the reaction is fast, control becomes difficult, and the particle size fluctuation tends to increase. To be more.

Next, the above-mentioned hydrolysis catalyst is continuously or intermittently added to the lower layer while gently stirring the mixed solvent phase of the lower alcohol and water.
The addition amount of the catalyst for hydrolysis is not particularly limited as long as all of the organosilicon compound can be hydrolyzed, and varies depending on the kind of the organosilicon compound, but the pH of the dispersion is preferably 7 to 13, more preferably 8 to 12. It is preferable to add so that it may become a range.
When the pH of the dispersion is less than 7, hydrolysis of the organosilicon compound does not occur easily and the formation of spherical micelles tends to be insufficient, or the particle size variation tends to increase.
When the pH of the dispersion exceeds 13, the reaction is fast, spherical micelles are not formed, the particle size fluctuation tends to increase, and there are cases where the particles are irregular (non-spherical) or a lot of gel is formed. is there.

The temperature at the time of hydrolysis varies depending on the type, boiling point, concentration and the like of the alcohol used, but is preferably in the range of −10 to 60 ° C., more preferably 5 to 50 ° C.
When the hydrolysis temperature is lower than −10 ° C., the organosilicon compound does not readily hydrolyze, and the formation of spherical micelles tends to be insufficient.
When the hydrolysis temperature exceeds 60 ° C., the organosilicon compound is rapidly hydrolyzed and the particle size variation tends to increase.

  After completion of the addition of the hydrolysis catalyst, it can be aged as necessary. By aging, the unreacted organosilicon compound disappears, the resulting polyorganosiloxane particles become more uniform (CV value decreases), and the production reproducibility is improved. The aging temperature may be the same as at the time of hydrolysis, but it may be high, and it is usually maintained at a temperature of about 20 to 95 ° C., preferably 30 to 90 ° C. for about 0.5 to 2 hours.

After the addition of the hydrolysis catalyst or after ripening, the particles are separated from the dispersion, washed with an organic solvent such as alcohol as necessary, and then dried and / or heat-treated.
Drying conditions and heat treatment conditions can be appropriately selected depending on the size of the particles, the usage of the particles, the type of resin to be blended, the blending amount and the like.
Particles dried at about 50 to 200 ° C. or heat-treated and dried at a relatively low temperature of about 200 to 500 ° C. have excellent dispersibility in the resin, but reduce the linear expansion coefficient of the substrate formed by blending with the resin. An effect may become inadequate, and when it heat-processes at a comparatively high temperature about 500-1200 degreeC, a linear expansion coefficient can be suppressed small.
The average particle diameter of the polyorganosiloxane particles thus obtained is preferably 0.5 to 30 μm, more preferably 1 to 20 μm.

Resin The resin used for the semiconductor device mounting paste of the present invention has a low viscosity of the semiconductor device mounting paste, and can quickly and densely fill the gap between the substrate and the semiconductor chip, causing cracks, or resin If there is no warping of the substrate due to the expansion of the substrate, there is no particular limitation. In addition, the semiconductor device mounting paste has a low viscosity, excellent coating properties, thixotropic properties (low reflow properties), and can be effectively bonded to the substrate and the semiconductor element (chip). Absent. As these resins, conventionally known epoxy resins, polyimide resins, bismaleimide resins, acrylic resins, methacrylic resins, silicon resins, BT resins, cyanate resins and the like can be suitably used. .
In the above, in order to reduce the viscosity of the paste, a resin having a low molecular weight, for example, a resin monomer, a resin oligomer, or the like can be mixed and used. Furthermore, a conventionally well-known solvent can also be mixed and used.

The resin content in the semiconductor device mounting paste is preferably 10 to 70% by weight, more preferably 20 to 60% by weight.
When the content of the resin in the paste for mounting a semiconductor device is less than 10% by weight, the amount of the resin is reduced, so that the adhesion to the substrate may be insufficient or the paste may have a high viscosity. In addition, the dispersibility becomes insufficient, and when used as a filler for the purpose of the present invention, particularly an underfill, the permeability may be insufficient.
If the resin content in the semiconductor device mounting paste exceeds 70% by weight, the number of particles is small, so the expansion coefficient is as large as that of the resin alone, and cracks may occur around the bumps. The substrate may be warped or the semiconductor element may be damaged. In addition, the permeability may be insufficient, and the narrow gap may not be filled quickly and densely.

Curing catalyst A curing catalyst can be used in the paste for mounting a semiconductor device of the present invention, if necessary. The curing catalyst varies depending on the resin, and examples thereof include organic anhydrides such as acid anhydrides, zinc naphthenate and tin octylate, organic amines such as triethylamine, imidazoles and phenol compounds. Examples of the acid anhydride include methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl nadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, and the like.

The paste for mounting a semiconductor device of the present invention is classified into two types of pastes according to the use and usage. One is a paste having low viscosity, reflowability, gap permeability, high adhesion, crack resistance, etc., and can be suitably used for underfill.
The other is a paste having a relatively low viscosity and thixotropy, specifically, the ability to maintain the shape without reflowing when the paste is dropped on the substrate. It can be suitably used for die attachment.

The paste for semiconductor mounting preferably has a viscosity (η ₁ ) of ₁ to 800 Pa · s, more preferably ₁ to 600 Pa · s when the rotation speed of the E-type viscometer is 0.5 rpm.
If the viscosity (η ₁ ) is less than 1 Pa · s, it is difficult to obtain, and even if it is obtained, it may be unsuitable for die attach. -May not be suitable for filling. Here, for underfill, it is preferably 50 Pa · s or less.

Moreover, it is preferable that the viscosity (η ₂ ) when the rotation speed of the E-type viscometer is 2.5 rpm is in the range of 1 to 800 Pa · s, more preferably 1 to 600 Pa · s.
When the viscosity (η ₂ ) is less than 1 Pa · s, it is difficult to obtain, and even if it is obtained, it may be unsuitable for die attach. -May not be suitable for filling. Also in this case, it is preferable that the pressure is 50 Pa · s or less for the underfill.

In the above, the viscosity (eta ₁₎ and viscosity ratio of the viscosity _{(η 2) (η 1)} / (η 2) is preferably in the range of from 0.001 to 8.
Here, the under - preferably a viscosity ratio _{(η 1) / (η 2} ) is in the range of 0.001 to 1 as a fill, the viscosity ratio as a die attach _{(η 1) / (η 2} ) Is preferably in the range of 2-8.
The viscosity in the present invention is measured with an E-type viscometer (manufactured by Toki Sangyo Co., Ltd .: TVE25H) at a measurement temperature of 30 ± 5 ° C.
Such a paste for mounting a semiconductor device is prepared by blending the polyorganosiloxane particles, the resin, and a curing catalyst as necessary, kneading, and defoaming under reduced pressure as necessary. be able to.

Example of Application to Semiconductor Device Next, a case where the above-described paste for mounting a semiconductor device is used as an underfill material and a die attach material in a semiconductor device will be exemplified.
The paste for mounting a semiconductor device of the present invention is used for a semiconductor device as shown in FIG. 1, for example.
The semiconductor device (1) includes a BGA substrate (2), a semiconductor chip (3) mounted on the BGA substrate (2), and a BGA substrate (2) and a semiconductor chip (3) provided between them. A touch material (4) is provided.
Further, as shown in FIG. 1, the semiconductor device (1) is mounted on the printed wiring board (6) via the solder balls (5) and then filled with the underfill material (7).

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.

[Example 1]
Preparation of polyorganosiloxane particles (1) 168 g of 1-pentanol and 252 g of methanol were mixed with 16760 g of water to prepare a water-alcohol mixed solvent adjusted to a temperature of 20C.
To the water-alcohol mixed solvent, 1362 g of methyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd .: KBM-13) was added dropwise as an organosilicon compound.
Subsequently, 96.4 g of aqueous ammonia having a concentration of 2.8% by weight was added in about 1 minute while gently stirring the lower layer water-alcohol mixed solvent. The pH of the mixed solvent phase after the addition was 10.4. It took 30 minutes for the organic solvent compound phase to disappear in the mixed solvent phase. Subsequently, aging was performed at 80 ° C. for 15 hours.
Subsequently, it was separated and washed with a centrifuge, then dried at 110 ° C. for 15 hours and then calcined at 1000 ° C. for 3 hours to prepare polyorganosiloxane particles (1).
The obtained polyorganosiloxane particles (1) were measured for average particle size and particle size variation coefficient, and the results are shown in the table.

Preparation of paste for semiconductor mounting (1 ) 100 g of bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd .: jER 801) containing glycidyl ether, 455 g of polyorganosiloxane particles (1), acid as curing agent A semiconductor mounting paste (1) was prepared by thoroughly mixing 95 g of an anhydride (methyltetrahydrophthalic anhydride) (Mitsubishi Chemical Corporation: jER Cure YH-307).
About the obtained semiconductor mounting paste (1), dispersibility, viscosity, gap permeability, and dropping test were measured by the following methods, and the results are shown in the table.

A paste is dropped on a dispersible glass substrate, covered with a cover glass, and a 100 g load is maintained for 30 seconds, and then the spread paste is observed with an optical microscope at 50 times magnification to disperse particles. The state was confirmed and evaluated according to the following criteria.
Almost no fixed particles were observed: ◎
Slightly fixed particles were observed: ○
Many fixed particles were observed: △
Few non-adherent particles were found: ×

Using a viscosity E-type viscometer (manufactured by Toki Sangyo Co., Ltd .: TVE25H), the viscosity (η ₁ ) at a rotation speed of 0.5 rpm at 30 ° C. and the viscosity (η ₂ ) at 2.5 rpm are measured, and the viscosity ratio (Η ₁ ) / (η ₂ ) was determined.

Drop test (reflow property)
A paste is dropped on a copper frame whose surface is silver-plated, and immediately covered with a cover glass. After holding a load of 20 g for 10 seconds, the diameter of the spread paste is measured. Evaluation was based on criteria.
A: 10 mm or more (suitable as an underfill agent)
B: 5 mm or more and less than 10 mm C: less than 5 mm (suitable as a die attach agent)

Crevice penetration property A glass space structure (gap width of about 20 μm, length of 20 mm) is formed with a glass substrate and a heat-resistant tape (kapton tape), heated to a temperature of 100 ° C., and then a semiconductor. The mounting paste (1) was hung on one side of the glass substrate, penetrated into the glass gap by capillary action, measured for the time to reach the other side, and evaluated according to the following criteria. A: 10 seconds or less (under Suitable as a fill agent)
B: 11 to less than 20 seconds C: 20 seconds or more

[Example 2]
Preparation of polyorganosiloxane particles (2)
A water-alcohol mixed solvent adjusted to a temperature of 20 ° C. was prepared by mixing 16760 g of water with 42 g of 1-pentanol and 378 g of methanol.
To the water-alcohol mixed solvent, 1362 g of methyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd .: KBM-13) was added dropwise as an organosilicon compound.
Subsequently, 96.4 g of aqueous ammonia having a concentration of 2.8% by weight was added in about 1 minute while gently stirring the lower layer water-alcohol mixed solvent. The pH of the mixed solvent phase after the addition was 10.5. It took 15 minutes for the organic solvent compound phase to disappear in the mixed solvent phase. Subsequently, aging was performed at 80 ° C. for 15 hours.
Subsequently, it was separated and washed with a centrifugal separator, then dried at 110 ° C. for 15 hours and then calcined at 1000 ° C. for 3 hours to prepare polyorganosiloxane particles (2).
The resulting polyorganosiloxane particles (2) were measured for average particle size and particle size variation coefficient, and the results are shown in the table.

Preparation of semiconductor mounting paste (2) A semiconductor mounting paste (2) was prepared in the same manner as in Example 1 except that the polyorganosiloxane particles (2) were used.
The obtained semiconductor mounting paste (2) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 3]
Preparation of polyorganosiloxane particles (3) 16760 g of water was mixed with 42 g of 1-pentanol and 378 g of methanol to prepare a water-alcohol mixed solvent adjusted to a temperature of 20C.
To the water-alcohol mixed solvent, 681 g of methyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd .: KBM-13) was added dropwise as an organosilicon compound.
Subsequently, 96.4 g of aqueous ammonia having a concentration of 2.8% by weight was added in about 1 minute while gently stirring the lower layer water-alcohol mixed solvent. The pH of the mixed solvent phase after the addition was 10.5. It took 15 minutes for the organic solvent compound phase to disappear in the mixed solvent phase. Subsequently, aging was performed at 80 ° C. for 15 hours.
Subsequently, it was separated and washed with a centrifugal separator, then dried at 110 ° C. for 15 hours and then calcined at 1000 ° C. for 3 hours to prepare polyorganosiloxane particles (3).
The resulting polyorganosiloxane particles (3) were measured for average particle size and particle size variation coefficient, and the results are shown in the table.

Preparation of semiconductor mounting paste (3) A semiconductor mounting paste (3) was prepared in the same manner as in Example 1 except that the polyorganosiloxane particles (3) were used.
The obtained semiconductor mounting paste (3) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 4]
Preparation of paste for semiconductor mounting (4) Polyorganosiloxane particles prepared in the same manner as in Example 2 with 100 g of bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd .: jER 801) containing glycidyl ether (2) 293 g and 95 g of acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Co., Ltd .: jER Cure YH-307) as a curing agent are mixed thoroughly to obtain a semiconductor mounting paste (4). Prepared.
The obtained semiconductor mounting paste (4) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 5]

Preparation of paste for semiconductor mounting (5) Polyorganosiloxane particles prepared in the same manner as in Example 2 with 100 g of bisphenol A type epoxy resin containing glycidyl ether (Mitsubishi Chemical Corporation: jER 801) (2) A semiconductor mounting paste (5) was prepared by thoroughly mixing 780 g and 95 g of acid anhydride (methyltetrahydrophthalic anhydride) (Mitsubishi Chemical Corporation: jER Cure YH-307) as a curing agent. Prepared.
The obtained semiconductor mounting paste (5) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 6]
Preparation of paste for semiconductor mounting (6) Polyorganosiloxane particles prepared in the same manner as in Example 2 with 100 g of silicone-modified polyimide resin (X-22-8904, manufactured by Shin-Etsu Chemical Co., Ltd.) 2) A semiconductor mounting paste (6) was prepared by thoroughly mixing 233 g.
The obtained semiconductor mounting paste (6) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Comparative Example 1]
Preparation of polyorganosiloxane particles (R1) A water-alcohol mixed solvent adjusted to a temperature of 5C was prepared by mixing 16760 g of water with 42 g of 1-pentanol and 378 g of methanol.
To the water-alcohol mixed solvent, 1362 g of methyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd .: KBM-13) was added dropwise as an organosilicon compound.
Next, 96.4 g of 2.8 wt% ammonia water was added in about 1 minute while sufficiently stirring the lower layer water-alcohol mixed solvent at twice the speed of Example 2. The pH of the mixed solvent phase after the addition was 10.5. It took 15 minutes for the organic solvent compound phase to disappear in the mixed solvent phase. Subsequently, aging was performed at 80 ° C. for 15 hours.
Subsequently, separation and washing were performed with a centrifugal separator, followed by drying at 110 ° C. for 15 hours and then baking at 1000 ° C. for 3 hours to prepare polyorganosiloxane particles (R1).
The resulting polyorganosiloxane particles (R1) were measured for average particle size and particle size variation coefficient, and the results are shown in the table.

Preparation of semiconductor mounting paste (R1) A semiconductor mounting paste (R1) was prepared in the same manner as in Example 1 except that the polyorganosiloxane particles (R1) were used.
The obtained semiconductor mounting paste (R1) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Comparative Example 2]
Preparation of paste for semiconductor mounting (R2) 100 g of bisphenol A type epoxy resin containing glycidyl ether (Mitsubishi Chemical Co., Ltd .: jER 801) and silica fine particles (manufactured by JGC Catalysts & Chemicals Co., Ltd .: Shinji) Sphere SW, average particle size: 3.3 μm, CV value: 1.5%) 455 g, acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Co., Ltd .: jER Cure YH-307) as a curing agent, 95 g A semiconductor mounting paste (R2) was prepared by thoroughly mixing the above.
The obtained semiconductor mounting paste (R2) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Comparative Example 3]
Preparation of paste for semiconductor mounting (R3) 100 g of bisphenol A type epoxy resin containing glycidyl ether (Mitsubishi Chemical Co., Ltd .: jER 801) and silica fine particles (manufactured by JGC Catalysts & Chemicals Co., Ltd .: Shinji) Sphere SW, average particle size: 1.4 μm, CV value: 2.0%) 455 g, acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Corporation: jER Cure YH-307) 95 g as a curing agent A semiconductor mounting paste (R3) was prepared by thoroughly mixing the above.
The obtained semiconductor mounting paste (R3) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 7]
Preparation of paste for semiconductor mounting (7) 100 g of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation: jER 828) and polyorganosiloxane particles (1) prepared in the same manner as in Example 1. A semiconductor mounting paste (7) was prepared by thoroughly mixing 140 g and 110 g of acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Corporation: jER Cure YH-307) as a curing agent.
The obtained semiconductor mounting paste (7) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 8]
Preparation of paste for semiconductor mounting (8) 100 g of bisphenol A type epoxy resin (Mitsubishi Chemical Corporation: jER 828) and polyorganosiloxane particles (2) prepared in the same manner as in Example 2 A semiconductor mounting paste (8) was prepared by thoroughly mixing 140 g and 110 g of acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Co., Ltd .: jER Cure YH-307) as a curing agent.
The obtained semiconductor mounting paste (8) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 9]
Preparation of paste for semiconductor mounting (9) 100 g of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation: jER 828) and polyorganosiloxane particles (3) prepared in the same manner as in Example 3. A semiconductor mounting paste (9) was prepared by thoroughly mixing 140 g and 110 g of acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Corporation: jER Cure YH-307) as a curing agent.
The obtained semiconductor mounting paste (9) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 10]
Preparation of paste for semiconductor mounting (10) 110 g of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation: jER 828) and polyorganosiloxane particles (2) prepared in the same manner as in Example 2. 90 g and 110 g of acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Corporation: jER Cure YH-307) as a curing agent were sufficiently mixed to prepare a semiconductor mounting paste (10).
The obtained semiconductor mounting paste (10) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 11]
Preparation of paste for semiconductor mounting (11) 100 g of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation: jER 828) and polyorganosiloxane particles (2) prepared in the same manner as in Example 2 A semiconductor mounting paste (11) was prepared by thoroughly mixing 210 g and 110 g of acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Corporation: jER Cure YH-307) as a curing agent.
The obtained semiconductor mounting paste (11) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Example 12]
Preparation of paste for semiconductor mounting (12) 100 g of polyimide resin (manufactured by Toray Industries, Inc .: Semicofine SP-811) and 67 g of polyorganosiloxane particles (2) prepared in the same manner as in Example 2 A semiconductor mounting paste (12) was prepared by mixing with the above.
The obtained semiconductor mounting paste (12) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Comparative Example 4]
Preparation of paste for semiconductor mounting (R4) 140 g of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation: jER 828) and polyorganosiloxane particles (R1) prepared in the same manner as in Comparative Example 1 A semiconductor mounting paste (R4) was prepared by thoroughly mixing 140 g and 110 g of acid anhydride (methyltetrahydrophthalic anhydride) (Mitsubishi Chemical Co., Ltd .: jER Cure YH-307) as a curing agent.
The obtained semiconductor mounting paste (R4) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Comparative Example 5]
Preparation of paste for semiconductor mounting (R5) 100 g of bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd. product: jER 828) and silica fine particles (manufactured by JGC Catalysts & Chemicals Co., Ltd .: True Ryukyu SW, average Particle size: 3.3 μm, CV value: 1.5%) 140 g and acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Co., Ltd .: jER Cure YH-307) 110 g as a curing agent are thoroughly mixed. A semiconductor mounting paste (R5) was prepared.
The obtained semiconductor mounting paste (R5) was subjected to dispersibility, viscosity, gap permeability, and dropping test, and the results are shown in the table.

[Comparative Example 6]
Preparation of paste for semiconductor mounting (R6) 100 g of bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd .: jER 828) and silica fine particles (manufactured by JGC Catalysts & Chemicals Co., Ltd .: true Ryukyu SW, average Particle size: 1.4 μm, CV value: 2.0%) 140 g, acid anhydride (methyltetrahydrophthalic anhydride) (manufactured by Mitsubishi Chemical Corporation: jER Cure YH-307) 110 g as a curing agent A semiconductor mounting paste (R6) was prepared.
As a result of evaluating the dispersibility of the obtained semiconductor mounting paste (R6), a remarkable aggregation state was observed, and thus viscosity measurement, gap permeability, and a dropping test were not performed.

Claims (6)

  A paste for mounting a semiconductor device comprising a polyorganosiloxane particle having an average particle size in the range of 0.5 to 30 μm and a particle size variation coefficient (CV value) of 3% or less and a resin.   2. The semiconductor device mounting paste according to claim 1, wherein the content of the polyorganosiloxane particles is in the range of 30 to 90% by weight.   The resin is one or more selected from an epoxy resin, a polyimide resin, a bismaleimide resin, an acrylic resin, a methacrylic resin, a silicone resin, a BT resin, and a cyanate resin. 3. The semiconductor device mounting paste according to claim 1, wherein the semiconductor device mounting paste is provided. 4. The semiconductor device mounting page according to claim 1, wherein the viscosity (η ₁ ) of the E-type viscometer at a rotation speed of 0.5 rpm is in the range of ₁ to 800 Pa · s. Strike. 5. The semiconductor device mounting page according to claim 1, wherein the viscosity (η ₂ ) of the E-type viscometer at a rotational speed of 2.5 rpm is in the range of 1 to 800 Pa · s. Strike. To claim 1, wherein the viscosity (eta ₁₎ and the viscosity (eta ₂₎ and the viscosity ratio of _{(η 1) / (η 2} ) is characterized in that in the range of from 0.001 to 8 The semiconductor device mounting paste described.

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