KR20110018309A - Amorphous siliceous powder, process for production of the same, and use thereof - Google Patents

Abstract

The present invention provides a resin composition, in particular a semiconductor sealing material, in which the viscosity at the time of sealing is low and the moldability is further improved even when the inorganic filler is filled high. In addition, there is provided a method for producing amorphous silicate powder and amorphous silicate powder, which are preferable for producing such a resin composition. In the amorphous silica-like powder of the present invention, after the pyridine is adsorbed to the amorphous silica-like powder, the amount of pyridine release L during heating at 450 ° C. or higher and less than 550 ° C. and pyridine at heating and heating at 150 ° C. or higher and less than 250 ° C. The ratio L / B of the deviation amount B of is 0.8 or less. In addition, the ratio (B / A) x 100% of the amount of pyridine leaving B at the time of heating of 150 to 250 degreeC which occupies for the total amount of pyridine leaving A at the time of 150 degreeC or more and less than 550 degreeC is 20%. It is preferable that it is above. In addition, the amorphous siliceous powder preferably has a specific surface area of 0.5 to 45 m 2 / g, an average particle diameter of 0.1 to 60 μm, and an average sphericity of 0.80 or more.

Description

Amorphous Silica Powder, Manufacturing Method and Use thereof {AMORPHOUS SILICEOUS POWDER, PROCESS FOR PRODUCTION OF THE SAME, AND USE THEREOF}

The present invention relates to amorphous siliceous powders, methods for their preparation and uses.

In recent years, due to the increasing awareness of global environmental conservation, the semiconductor sealing material used for sealing semiconductor elements is provided with flame retardancy without the use of harmful flame retardants such as antimony compounds and brominated epoxy resins, which have a high environmental load. It is desired to provide heat resistance to lead-free solder. The semiconductor sealing material is mainly composed of an epoxy resin, a phenol resin curing agent, a curing accelerator, an inorganic filler, and the like. However, in order to satisfy the above-described characteristics, the semiconductor sealing material has a high flame retardancy and high heat resistance structure containing many aromatic rings in an epoxy resin, a phenol resin, and the like. The method of applying a thing, the method of high filling an inorganic filler, etc. are taken. However, in these methods, the viscosity at the time of sealing of a semiconductor sealing material tends to increase.

On the other hand, in response to the demand for small size, light weight, and high performance of electronic devices, the internal structure of semiconductors is rapidly progressing in thinning of elements, small diameters of gold wires, long spans, and high density of wiring pitches. Sealing such a semiconductor using a highly viscous semiconductor sealing material results in an increase in defects such as deformation of the gold wire, cutting of the gold wire, inclination of the semiconductor element, and uncharged gap. For this reason, there is a strong demand for a semiconductor sealing material to have flame retardancy, to lower the viscosity at the time of sealing, and to reduce molding defects.

In order to satisfy such a demand, the method of aiming at low viscosity and improving moldability by the method of improving the epoxy resin, phenol resin hardening | curing agent used for a semiconductor sealing material, etc. is taken (refer patent document 1 and 2). Moreover, as improvement of a hardening accelerator, the method called so called latent which uses the component which suppresses hardenability, and protects a reactive substrate for the purpose of raising the hardening start temperature of an epoxy resin is taken (patent document 3 and 4). Reference).

As an improvement of an inorganic filler, the method etc. which adjust the particle size distribution so that the viscosity of a sealing material may not rise even if it is high charge is taken (refer patent document 5 and 6). However, in such a method, a low viscosity effect and an effect of improving moldability are not sufficient, and there is no semiconductor sealing material which can high-fill the inorganic filler, lower the viscosity at the time of sealing, and further improve moldability.

Japanese Patent Publication No. 2007-231159 Japanese Patent Laid-Open No. 2007-262385 Japanese Patent Laid-Open No. 2006-225630 Japanese Patent Laid-Open No. 2002-284859 Japanese Patent Laid-Open No. 2005-239892 WO / 2007/132771 publication

SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor sealing material having a low viscosity at the time of sealing even with high filling of an inorganic filler and further improving moldability, and providing an amorphous silica powder and a method for producing the same.

According to the present invention, after adsorbing pyridine to amorphous silica-like powder, the amount of pyridine leaving L during heating of 450 ° C. or higher and less than 550 ° C., and the amount of pyridine leaving B during heating of 150 ° C. or higher and less than 250 ° C. It is an amorphous siliceous powder whose ratio L / B is 0.8 or less.

In addition, in this invention, after making pyridine adsorb | suck to an amorphous siliceous powder, the amount of pyridine leaving at the time of the heating of 150 degreeC or more and less than 250 degreeC which occupies for the total amount of pyridine A when heating 150 degreeC or more and less than 550 degreeC. It is preferable that ratio (B / A) * 100% of B is 20% or more.

In addition, the amorphous siliceous powder of the present invention preferably has a specific surface area of 0.5 to 45 m 2 / g, an average particle diameter of 0.1 to 60 µm, and an average sphericity of 0.80 or more.

Moreover, this invention is an inorganic powder containing the amorphous silica powder of this invention.

In the present invention, the inorganic powder is preferably amorphous silica powder and / or alumina powder other than the present invention.

In addition, the present invention is prepared by spraying a mixture containing a raw silicate powder and an Al source material into a flame formed by a burner to produce an amorphous silicate powder, and then an atmosphere having a temperature of 60 to 150 ° C and a relative humidity of 60 to 90%. It is a method for producing an amorphous silica-based powder, characterized in that maintained for 15 to 30 minutes under.

Moreover, this invention is a resin composition which contains the amorphous silica-like powder of this invention in resin. As said resin, an epoxy resin is preferable.

Moreover, this invention is a semiconductor sealing material using these resin compositions.

According to this invention, the resin composition excellent in fluidity | liquidity, a viscosity characteristic, and moldability, and also the semiconductor sealing material using the said resin composition is provided. In addition, an amorphous silicaous powder is provided which is suitable for producing the resin composition.

Hereinafter, the present invention will be described in detail.

In the amorphous silica-like powder of the present invention, the amount of pyridine released when the pyridine is adsorbed and the heating is removed, and the amount of pyridine released when the heating is performed at a temperature of 450 ° C. or higher and less than 550 ° C. It is an amorphous silica-like powder whose ratio L / B of B is 0.8 or less.

In the structure of silica, when Al is substituted at the position of Si, for example, -O-Si-O-Al-O-Si-O-, the point is determined from the difference between the coordination number of Si and the coordination number of Al. It becomes phosphorus Lewis acid point (electron pair acceptor). When H ₂ O (water) is bonded to this Lewis acid point, it becomes Bronsted acid point (proton donor). The basic substance pyridine binds to these acid points on the surface of the amorphous silica-like powder, and the more strongly bound pyridine is released at a higher temperature than when heated. In the case of amorphous siliceous powder, distribution occurs in acid strength (leaving temperature) because the structure is random compared to crystalline, but pyridine leaving at a heating temperature of approximately 150 ° C to 250 ° C is combined with Bronsted acid point, 450 ° C. It is thought that the pyridine leaving at the heating temperature of 550 degreeC couple | bonded with the Lewis acid point.

When the pyridine is adsorbed and heated, the ratio L / B of the release amount L of pyridine in heating at 450 ° C. or higher and lower than 550 ° C. and the release amount B of pyridine in heating at 150 ° C. or higher and less than 250 ° C. is 0.8 or less. That means that the amount of Bronsted acid point is 1.25 times more than the amount of Lewis acid point. When such an amorphous silica is used, it becomes possible to manufacture the sealing material excellent in fluidity | liquidity, a viscosity characteristic, and moldability for the reason mentioned later. Conversely, when the ratio L / B of the amount L of pyridine released at the heating of 450 ° C. or more and less than 550 ° C. and the amount B of the pyridine release B at the temperature of 150 ° C. or more and less than 250 ° C. exceeds 0.8, Br. It means that the amount of the ted acid point is less than 1.25 times the amount of the Lewis acid point, and it becomes difficult to produce a sealing material excellent in fluidity, viscosity characteristics and moldability.

The reason for expression of the effect according to the present invention is as follows. That is, an epoxy resin, a phenol resin hardening | curing agent, and a hardening accelerator are used for a semiconductor sealing material as a main component other than amorphous silicate powder. When the semiconductor sealing material is heated to about 150 ° C. to 200 ° C., which is a general heat curing temperature (molding temperature), the proton of the phenol resin curing agent is released by the curing accelerator, and the anion polymerization chain reaction of the epoxy resin and the phenol resin curing agent proceeds to heat the sealing material. Cures. In the case of using the amorphous silica-like powder of the present invention, protons are released from the Bronsted acid point by heating. This proton binds to the anionic polymerization terminal, and the polymerization chain reaction is suspended temporarily, resulting in a delay in thermal curing of the sealing material. That is, the amorphous silica-like powder of this invention makes it possible to latent thermosetting of a sealing material, and can manufacture the sealing material excellent in the fluidity | liquidity and the viscosity characteristic at the time of shaping | molding. The latent effect is remarkable only when the ratio L / B of the release amount L of pyridine in heating at 450 ° C. or higher and lower than 550 ° C. and the release amount B of pyridine in heating at 150 ° C. or higher and lower than 250 ° C. is 0.8 or lower. do. Under this mechanism, there have been no examples of giving latent potential to amorphous siliceous powders.

On the other hand, when the ratio L / B of the leaving amount L of pyridine at the time of heating at 450 degreeC or more and less than 550 degreeC, and the leaving amount B of the pyridine at heating time of 150 degreeC or more and less than 250 degreeC exceeds 0.8, Not only is the latent potential of the sealing material by proton release from the Brönsted acid point of the amorphous silica powder as described above, but also oxygen coordination bonds to the Lewis acid point, and conversely the flow of the amorphous silica powder It is not preferable because it inhibits the fluidity and viscosity characteristics of the sealing material. Preferable L / B ratio is 0.7 or less, More preferably, it is 0.6 or less.

The release temperature and the amount of release of pyridine from the amorphous silica-like powder can be measured by the following procedure.

(1) Preparation of pyridine solution: 7.91 g of pyridine for spectroscopic analysis is weighed into a 500 ml volumetric flask and brought to a constant volume with n-heptane for spectroscopic analysis. Subsequently, 1 ml of this pyridine solution is taken in a 200 ml volumetric flask and brought to a constant volume with n-heptane.

(2) Adsorption of Pyridine to Amorphous Silica Powder: 4.00 g of amorphous silica powder, previously dried by heating at 200 ° C. in air for 2 hours and cooled in a desiccator with magnesium perchlorate desiccant, to a 25 ml volumetric flask. It is correct. 20 ml of the pyridine solution is added to the volumetric flask and shaken for 3 minutes. The flask was placed in a thermostat set at 25 ° C. and held for 2 hours, and pyridine was adsorbed onto the amorphous silica powder.

(3) Cleaning of amorphous silicaous powder: In order to clean the pyridine physically adsorbed to the amorphous silicaous powder, a shake flask taken out of the thermostat is shaken and mixed, and left to stand for 10 minutes to settle the amorphous silicaous powder. The supernatant of the pyridine solution is discarded, and about 20 ml of n-heptane for spectroscopic analysis is added, and the flask is shaken and left to stand for 10 minutes. The supernatant is placed in a measurement cell of an ultraviolet visible spectrophotometer, and the absorbance in the wavelength range of 190 to 340 nm is measured to confirm the absorption of pyridine at 251 nm. The washing operation with this n-heptane is repeated until no absorption of pyridine is confirmed in the supernatant of n-heptane. If the absorption of pyridine is not confirmed, the supernatant is discarded and the amorphous siliceous powder is dried at room temperature while blowing dry nitrogen gas at a flow rate of 100 ml / min for 10 minutes from the top of the flask.

(4) Determination of pyridine elimination temperature and amount of desorption: 10 mg of dry amorphous siliceous powder is quantified in a double shot pyrolyzer sample cup, and the mass spectrum of pyridine is monitored by heating with a pyrolysis device to monitor the pyridine mass. The departure temperature and the amount of departure are measured. The removal amount ratio of pyridine can be calculated from the area ratio of the obtained profile.

Moreover, when the ultraviolet visible spectrophotometer used for the confirmation of the presence or absence of the physically adsorbed pyridine is illustrated, it is a brand name "ultraviolet visible spectrophotometer model UV-1800" by Shimadzu Corporation. For measurement, a cell of 10 mm thickness made of quartz glass was used.

Illustrative reagents used to prepare pyridine solutions are Wako Junyaku Co., Ltd. pyridine (spectral analysis grade) and n-heptane (spectral analysis grade).

Moreover, when the apparatus used for the measurement of the detachment temperature and the detachment amount of the pyridine adsorb | sucked to an amorphous silicaous powder is illustrated, it is a thermal decomposition apparatus and the brand name "double short pyroiser model PY-2020D" made by FRONTIER LAB. , GC / MS measuring apparatus, and the brand name "GC / MSD model 6890/5973" by Agilent.

The measurement conditions of a thermal decomposition furnace are temperature rising rate from 50-700 degreeC at a temperature increase rate of 25 degree-C / min, ITF temperature: temperature increase to 150-300 degreeC, and measuring mode: EGA TEMP PROG. The measurement conditions of GC / MS are column: UADTM-2.5N (without liquid) 0.15 mmφ × 2.5 m, oven temperature: 300 ° C., inlet temperature: 280 ° C., measurement mode: SIM, split ratio: 30: 1, monitor Ion: m / z = 52, 79. In addition, the sum of the leaving amount of monitor ion 52 and 79 was made into the leaving amount of pyridine.

Since the amount of pyridine released is very small, it is difficult to quantitatively determine the absolute amount, but based on the abundance measured by the above measuring method, the amount of pyridine released L and 150 at the time of heating from 450 ° C. to 550 ° C. The total amount A of pyridine leaving when the heating amount is less than or equal to B, and the pyridine is leaving when the heating is less than or equal to 250 ° C. It is possible to accurately determine the ratio of the amount B. If pyridine is not adsorbed or released, the abundance becomes zero, and the larger the adsorption / release, the larger the abundance. In order to express the fluidity | liquidity, a viscosity characteristic, and the improvement effect of moldability like this invention, the maximum value of the escape amount presence rate of pyridine at the time of 150 degreeC or more and less than 250 degreeC needs to be 100 or more, Preferably it is 200 or more. . When the maximum value of abundance is less than 100, even if L / B ratio satisfy | fills a predetermined value, it becomes difficult to express the effect of this invention.

In addition, abundance is a numerical value obtained uniquely from the said measuring method.

The effects of improving the fluidity, the viscosity characteristics and the moldability of the amorphous silica-like powder as in the present invention are promoted when the amorphous silica-like powder is under the following conditions. That is, the ratio (B / A) × 100% of the amount of pyridine leaving B at the time of heating of 150 to 250 degreeC occupies in the total amount of pyridine leaving A at the time of the heating of 150 degreeC or more and less than 550 degreeC is 20%. We say that it is ideal. As described above, the general heat curing temperature (molding temperature) of the semiconductor sealing material is about 150 ° C to 200 ° C, and the amount of pyridine released during heating of 250 ° C or more and less than 550 ° C causes the potential of the semiconductor sealing material to be released by proton release. Not only are they difficult to contribute to, but the amount L of pyridine released from heating at a temperature of 450 ° C. or more and less than 550 ° C. is not preferable because, on the contrary, it inhibits the flow of the amorphous silica-like powder and deteriorates the fluidity and viscosity characteristics of the sealing material. Therefore, the ratio (B / A) × 100% of the amount of pyridine leaving amount B at the heating of 150 degreeC or more and less than 250 degreeC which occupies for the total leaving amount A of pyridine in the heating of 150 degreeC or more and less than 550 degreeC is 20 It is preferable that it is% or more. When this ratio is 25% or more, more preferably 30% or more, the fluidity | liquidity and the viscosity characteristic improvement at the time of shaping | molding become especially remarkable.

In addition, the effects of improving the fluidity, the viscosity characteristics and the moldability as in the present invention are such that when the specific surface area of the amorphous silica-like powder is 0.5 to 45 m 2 / g, the average particle diameter is 0.1 to 60 µm and the average sphericity is 0.80 or more. Further encouraged.

If the specific surface area of the amorphous siliceous powder is less than 0.5 m 2 / g, the contact area between the epoxy resin and the phenolic resin curing agent and the amorphous siliceous powder surface is too small, and the latent effect due to proton emission is hardly expressed. On the other hand, when the specific surface area exceeds 45 m 2 / g, it means that the amorphous silica-like powder contains a large amount of small particles or irregularities on part or all of the particle surface, and when packaging a semiconductor using a semiconductor sealing material Since the viscosity of the sealing material increases, the moldability is impaired. Preferred specific surface areas range from 0.6 to 20 m 2 / g, more preferably from 0.7 to 10 m 2 / g.

Moreover, even if the average particle diameter of amorphous siliceous powder is less than 0.1 micrometer, since the viscosity of the sealing material at the time of packaging a semiconductor using a semiconductor sealing material rises similarly, moldability is impaired and it is unpreferable. On the contrary, when the average particle diameter exceeds 60 mu m, there is a problem that the semiconductor chip is damaged, or a problem that a homogeneous package without irregularities is not obtained. The range of a preferable average particle diameter is 2-55 micrometers, and a more preferable range is 3-50 micrometers. Moreover, it is preferable that the largest particle diameter is 196 micrometers or less, More preferably, it is 128 micrometers or less.

Moreover, 0.80 or more are preferable and, as for the average sphericity of the amorphous silica-like powder of this invention, 0.85 or more are more preferable.

The average particle diameter of the amorphous silica-like powder of this invention is measured based on the particle size measurement by a laser diffraction scattering method. The measuring machine uses a Silas brand name "Silas Granulometer Model 920" to disperse the amorphous silica-like powder in water, and measures by dispersing for 1 minute at an output of 200 W with an ultrasonic homogenizer. In addition, particle size distribution measurement was performed in particle size channels 0.3, 1, 1.5, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, and 192 micrometers. In the measured particle size distribution, the particle size at which the cumulative mass is 50% is the average particle diameter, and the particle size at which the cumulative mass is 100% is the maximum particle size.

The specific surface area of the amorphous silica-like powder of this invention is measured based on the specific surface area measurement by BET method. It measures using the mounttec company brand name "Mostov model HM-1208" as a specific surface area measuring device.

The amorphous silica-like powder of this invention can express the effect even if it mixes with another inorganic powder. It is preferable that the content rate of the amorphous silica powder of this invention in an inorganic powder is 2 mass% or more, Furthermore, it is preferable that it is 5 mass% or more. As a kind of inorganic powder, it is preferable that they are amorphous silica powder and / or alumina powder other than this invention. These powders may be used alone or in combination of two. In the case of lowering the thermal expansion rate of the semiconductor sealing material or reducing the wearability of the mold, amorphous silica powder is selected as the inorganic powder, and alumina powder is selected as the inorganic powder when giving the thermal conductivity of the semiconductor sealing material. Moreover, it is preferable that it is 95% or more, and, as for an amorphous silicaous powder, with the value of the amorphous rate measured by the method mentioned later, 97% or more is more preferable.

It is preferable that the amorphous rate measured by the following method of the amorphous silica-like powder of this invention is 95% or more, and it is more preferable that it is 97% or more. The amorphous rate is an X-ray in the range where 2θ of the CuKα ray is 26 ° to 27.5 ° using a powder X-ray diffraction apparatus (for example, the product name "Model Mini Flex" manufactured by RIGAKU Co., Ltd.). Diffraction analysis is performed and measured from the intensity ratio of specific diffraction peaks. In the case of silica powder, the crystalline silica has a main peak at 26.7 °, but there is no peak in amorphous silica. When amorphous silica and crystalline silica are mixed, a peak height of 26.7 ° depending on the ratio of crystalline silica is obtained. Therefore, from the ratio of the X-ray intensity of the sample to the X-ray intensity of the crystalline silica standard sample, the crystalline silica mixture ratio (sample X-ray diffraction intensity / X-ray diffraction intensity of crystalline silica) is calculated, and the amorphous rate is obtained from the following equation (1).

[Equation 1]

Amorphous rate (%) = (1-crystalline silica mixture ratio) × 100

The average sphericity of the amorphous silica powder, the inorganic powder and the alumina powder of the present invention is preferably 0.80 or more, and more preferably 0.85 or more. Thereby, the viscosity of the resin composition of this invention can be reduced and moldability can also be improved. The average sphericity is stored in an image analyzer (e.g., Mountain View, Inc. product name "MacView") captured by a stereoscopic microscope (e.g., Nikon Corporation brand name "Model SMZ-10 type"). Then, it measures by the projection area A and the perimeter length PM of particle | grains from a photograph. If the area of the circle corresponding to the ambient length PM is set to (B), the sphericity of the particles is A / B. Therefore, a circle having an ambient length equal to the ambient length PM of the sample is assumed. When B = πr ² , PM = 2πr, B = πr ² , and B = π × (PM / 2π) ² , and the sphericity of each particle becomes Sphericalness = A / B = A × 4π / (PM) ² . The sphericity of 200 arbitrary particles obtained in this way was calculated | required, and the average value was made into the average sphericity.

As a measuring method of sphericity other than the above, it is converted according to the equation (2) from the individual particle circularity automatically quantitatively measured by a particulate analysis apparatus (for example, manufactured by Sysmex Corporation; trade name "model FPIA-3000"). You can get it.

[Equation 2]

Sphericality = (circle) ²

Next, the manufacturing method of the amorphous silica-like powder of this invention is demonstrated.

In the production method of the present invention, after the mixture comprising the raw silicate powder and the Al source material is sprayed into a flame formed by a burner to produce an amorphous silicate powder, a temperature of 60 to 150 캜 and a relative humidity of 60 to 90% A method for producing an amorphous silica-like powder, which is maintained in an atmosphere for 15 to 30 minutes. A mixture containing the raw silicate powder and the Al source material is sprayed into a flame formed by a burner, and the Al source material is applied to the surface of the silicate powder at the same time as the raw silicate powder is melted (amorphized) and spheronized. After fusion is formed to form an -O-Si-O-Al-O-Si-O- structure, the mixture is maintained for 15 to 30 minutes in an atmosphere having a temperature of 60 to 150 ° C and a relative humidity of 60 to 90%, and 150 to 250 ° C. The removal amount B of pyridine at the time of less than heating, and the removal amount L of pyridine at the time of heating at 450 degreeC or more and less than 550 degreeC are adjusted. As a result, it is possible to produce an amorphous silica-based powder having the features of the present invention.

As a device which injects the mixture containing a raw material silicate powder and an Al source material into a flame, melts, fuses, and spheroidizes it, the thing which connected the collection apparatus to the furnace body provided with a burner, for example is used. do. The furnace body may be any of an open type or a closed type, or a vertical type or a horizontal type. The collecting device is provided with at least one of a gravity settling chamber, a cyclone, a bag filter, an electrostatic precipitator, etc., and can collect the amorphous silica powder produced by adjusting the collecting conditions. When the example is shown, it is Unexamined-Japanese-Patent No. 11-57451, Unexamined-Japanese-Patent No. 11-71107. In order to maintain the amorphous silica powder in a temperature of 60 to 150 ° C. and a relative humidity of 60 to 90% for 15 to 30 minutes, for example, a line for supplying steam to the collecting device is provided. The steam temperature and steam supply can be adjusted to suit your needs. In order to adjust the holding time, the opening and closing time of the discharge valve for discharging the amorphous silica-like powder from the collecting device to the outside of the system can be adjusted to a desired time.

Immediately after the mixture containing the raw silicate powder and the Al source material is injected into the flame formed by the burner, the type of acid point of the -O-Si-O-Al-O-Si-O- structure is affected by the high temperature flame. Is mostly converted to Lewis acid, Bronsted acid combined with H ₂ O contained in the combustion gas of flammable gas used in flame formation, and the adsorption release ratio L / B of pyridine exceeds 0.8 Is in. Therefore, in the amorphous silica-like powder not subjected to the same treatment as in the production method of the present invention, the fluidity and viscosity characteristics at the time of molding due to the latent effect are not improved.

If the humidity of the humidifying fat is less than 60% or the holding time is less than 15 minutes, the change of Lewis acid to Bronsted acid is not sufficient, and the pyridine leaving amount ratio L / B cannot be adjusted to 0.8 or less. In addition, when the humidity exceeds 90% or the holding time exceeds 30 minutes, the amorphous silica-like powder is agglomerated, which is not preferable because the moldability of the semiconductor sealing material is lowered.

More preferable humidification humidity is 65 to 85%, and humidification time is a range of 20-25 minutes. Similarly, when the humidification temperature is less than 60 ° C., H ₂ O is difficult to bond and the change in Lewis acid to Bronsted acid is insufficient, and as a result, the pyridine release amount ratio L / B cannot be adjusted to 0.8 or less. On the other hand, even if the holding temperature exceeds 150 ° C, the temperature is too high and H ₂ O hardly bonds, and therefore L / B cannot be made 0.8 or less. Only when it maintains in the temperature range of 60-150 degreeC, it becomes possible to adjust L / B ratio to 0.8 or less. More preferable holding temperature is 70-120 degreeC, More preferably, it is the range of 75-100 degreeC.

As raw material silicate powder, powders of naturally occurring silica-containing minerals such as high-purity silica, high-purity silica, quartz and quartz, and high-purity silica powders produced by synthetic methods such as precipitated silica and silica gel can be used. In consideration, silica powder is most preferred. The silica powder is commercially available in various particle sizes pulverized by a pulverizer such as a vibration mill or a ball mill, and the particle size can be appropriately selected so that a desired particle size of the amorphous silica powder can be obtained.

In the present invention, the Al source material is preferably aluminum oxide powder. Examples of the Al source material include aluminum oxide, aluminum hydroxide, aluminum nitrate, aluminum chloride, aluminum organic compounds, and the like. Among these, aluminum oxide is most preferable because it is close to the melting point of the raw silicate powder, and is easily fused to the surface of the raw silicate powder when injected from the burner, and the impurity content is also small.

Moreover, it is preferable that the average particle diameter of aluminum oxide powder is 0.01-10 micrometers. If the average particle diameter is less than 0.01 µm, the powder tends to aggregate, and the composition when fused with the siliceous powder tends to be heterogeneous, and similarly, the composition when fused with the siliceous powder becomes heterogeneous even when it exceeds 10 µm. . The range of preferable average particle diameters is 0.03-8 micrometers, More preferably, it is 0.05-5 micrometers.

Further, the content of Al ₂ O ₃ in the amorphous siliceous powder according to the present invention is preferably 0.1 to 20 mass%. If the content of Al ₂ O ₃ is less than 0.1% by mass, the increase in acid point is not sufficient. If the content of Al ₂ O ₃ exceeds 20% by mass, the thermal expansion coefficient of the amorphous silica powder becomes too large, which adversely affects the function of the original semiconductor sealing material. The preferred content of Al ₂ O ₃ is more preferably from 0.15 to 18% by mass, 0.2 to 15% by weight.

The Al ₂ O ₃ content (oxide conversion) of the amorphous silica-like powder of the present invention can be measured by the following procedure using atomic absorption spectrometry. That is, 1 g of amorphous siliceous powder is precisely placed in a platinum dish, and 20 ml and 1 ml of reagent express hydrofluoric acid and reagent express perchloric acid are added, respectively. The platinum dish is allowed to stand on a sand bath heated to 300 ° C. for 15 minutes, then cooled to room temperature, and transferred to a 25 ml volumetric flask to a constant volume with pure water. The amount of Al in this solution is quantified by the calibration curve method using an atomic absorption photometer. This amount of Al is converted to Al ₂ O ₃ to calculate the content of the amorphous silica-like powder. An example of an atomic absorption photometer is Nippon Jarrell Ash Co., Ltd. brand name "Atomic Absorption Photometer Model AA-969". An example of the standard liquid used to prepare the calibration curve is an Al standard liquid for absorbing atoms made by Kanto Chemical Co., Ltd. (concentration 1000 ppm). In addition, an acetylene-nitrous oxide frame is used for the frame at the time of a measurement, and the absorbance in wavelength 309.3 nm is measured and quantified.

In addition, in the present invention, the amount of pyridine released and the temperature of the pyridine when the pyridine is adsorbed and released from the amorphous silica powder are the size, amount, humidification holding condition, ratio of Al source material to be fused to the surface of the raw silica powder. It can adjust according to surface area, average particle diameter, etc.

The specific surface area and average particle diameter of amorphous silica powder can be adjusted according to the particle size structure, flame temperature, etc. of a raw silica powder. In addition, an average sphericity degree and an amorphous rate can be adjusted with supply amount of a raw material siliceous powder to flame, flame temperature, etc. Furthermore, various kinds of amorphous silica powders having different sizes, amounts, humidified maintenance conditions, specific surface areas, average particle diameters, etc. of the fused Al source material were prepared, and two or more of them were suitably mixed to adsorb and desorb pyridine. It is also possible to produce an amorphous silica-like powder in which the amount of pyridine released, the temperature of separation, the specific surface area, the average particle diameter, and the like are more specified.

The resin composition of this invention is a resin composition which contains the amorphous silica-like powder of this invention or the inorganic powder of this invention in resin. The content rate of the amorphous silica-like powder or the inorganic powder in the resin composition is 10 to 95 mass%, more preferably 30 to 90 mass%.

Examples of the resin include epoxy resins, silicone resins, phenol resins, melamine resins, urea resins, unsaturated polyesters, polyamides such as fluorine resins, polyimides, polyamideimide, polyetherimide, polybutylene terephthalate, polyethylene terephthalate and the like. Polyester, polyphenylene sulfide, aromatic polyester, polysulfone, liquid crystal polymer, polyether sulfone, polycarbonate, maleimide modified resin, ABS resin, AAS (acrylonitrile-acrylic rubber, styrene) resin, AES (Acrylonitrile, ethylene, propylene, diene rubber-styrene) resin and the like can be used.

Among them, an epoxy resin having two or more epoxy groups in one molecule is preferable as the resin for the semiconductor sealing material. For example, phenol novolak-type epoxy resins, ortho cresol novolak-type epoxy resins, epoxidized phenols and aldehydes novolak resins, glycidyl ethers such as bisphenol A, bisphenol F and bisphenol S, phthalic acid and dimers Glycidyl ester acid epoxy resin obtained by reaction of polybasic acids, such as an acid, and epichlorohydrin, a linear aliphatic epoxy resin, an alicyclic epoxy resin, a heterocyclic epoxy resin, alkyl modified polyfunctional epoxy resin, (beta) -naphthol novolak-type Epoxy resins, 1,6-dihydroxynaphthalene type epoxy resins, 2,7-dihydroxynaphthalene type epoxy resins, bishydroxybiphenyl type epoxy resins, and halogens such as bromine are introduced to impart flame retardancy. Epoxy resin and the like. Among these, in view of moisture resistance and solder reflow resistance, ortho cresol novolac type epoxy resins, bishydroxybiphenyl type epoxy resins, and epoxy resins of naphthalene skeletons are preferable.

The epoxy resin used by this invention contains the hardening | curing agent of an epoxy resin, or the hardening | curing agent of an epoxy resin, and the hardening accelerator of an epoxy resin. As a hardening | curing agent of an epoxy resin, 1 type, or 2 or more types of mixtures chosen from the group which consists of phenol, cresol, xylenol, resorcinol, chlorophenol, t-butylphenol, nonylphenol, isopropylphenol, and octyl phenol, for example 3, such as novolak-type resin, polyparahydroxystyrene resin, bisphenol compounds, such as bisphenol A or bisphenol S, pyrogalol, and phloroglucinol, which are obtained by reacting a formaldehyde, paraformaldehyde or paraxylene together with an oxidation catalyst. And functional phenols, maleic anhydride, acid anhydrides such as phthalic anhydride and pyromellitic anhydride, and aromatic amines such as metaphenylenediamine, diaminodiphenylmethane and diaminodiphenylsulfone.

Moreover, in order to accelerate reaction of an epoxy resin and a hardening | curing agent, hardening accelerators, such as a triphenylphosphine, benzyl dimethylamine, and 2-methylimidazole, can be used, for example.

The following components can be mix | blended further with the resin composition of this invention as needed. That is, as a low stress agent, silicone rubber, polysulfide rubber, acrylic rubber, butadiene rubber, rubbery materials such as styrene block copolymers or saturated elastomers, various thermoplastic resins, resinous materials such as silicone resins, and epoxy The resin etc. which modified | denatured some or all of resin and a phenol resin with amino silicone, epoxy silicone, alkoxy silicone, etc. are mentioned. Epoxysilanes, such as (gamma)-glycidoxy propyl trimethoxysilane and (beta)-(3, 4- epoxycyclohexyl) ethyl trimethoxysilane, an aminopropyl triethoxysilane, and ureido propyl triethoxysilane as a silane coupling agent And hydrophobic silane compounds such as aminosilane, such as N-phenylaminopropyltrimethoxysilane, phenyltrimethoxysilane, methyltrimethoxysilane, and octadecyltrimethoxysilane, and mercaptosilane. As a surface treating agent, a Zr chelate, a titanate coupling agent, an aluminum coupling agent, etc. are mentioned. As a flame retardant adjuvant, and the like _{Sb 2 O 3, Sb 2 O} 4, Sb 2 O 5. Halogenated epoxy resins, phosphorus compounds, etc. are mentioned as a flame retardant. Carbon black, iron oxide, dye, a pigment, etc. are mentioned as a coloring agent. Furthermore, natural waxes, synthetic waxes, metal salts of linear fatty acids, acid amides, esters, paraffins, etc. are mentioned as a mold release agent.

The resin composition of this invention can be manufactured by blending the predetermined amount of each said material with a blender, Henschel mixer, etc., and then cooling and grind | pulverizing what was kneaded with a heating roll, a kneading machine, a single screw, or a twin screw extruder.

The semiconductor sealing material of this invention is a thing in which a resin composition contains an epoxy resin and consists of a composition containing the hardening | curing agent of an epoxy resin, and the hardening accelerator of an epoxy resin.

In order to seal a semiconductor using the semiconductor sealing material of this invention, normal shaping | molding means, such as a transfer mold method and a vacuum printing mold method, is used.

[Example]

Hereinafter, although the Example of this invention demonstrates further in detail, it is not limited to these and interpreted.

Examples 1-10 and Comparative Examples 1-8

As a raw material used for the preparation of the amorphous silica-like powder of the present invention, a crystalline silica powder (SiO ₂ content of 99.9% by mass) manufactured by Kinsei Matec Co., Ltd., an alumina powder produced by Nippon Keiginjo Co., Ltd. and an aluminum hydroxide powder were used. Particle size adjustment was performed by pulverizing and classifying each powder, and various raw silicate powders and Al source materials having different average particle diameters were prepared. The apparatus described in Japanese Patent Application Laid-Open No. 11-57451, and a line for supplying a boiler and steam for generating steam to these collecting devices, are installed, and the steam temperature and the steam supply amount are adjusted so as to achieve a desired temperature and relative humidity. It can be adjusted. By using this apparatus, the raw materials were melted, fused, spheronized, and humidified in a flame to prepare various amorphous siliceous powders shown in Tables 1 and 2. In addition, these powders were suitably blended to prepare amorphous silicate powders and inorganic powders shown in Tables 3 and 4.

In addition, the amount of pyridine released and the temperature at which the pyridine is adsorbed and detached from the amorphous silica powder are the size, amount, humidification maintenance condition, specific surface area, and average particle diameter of the Al source material to be fused to the surface of the raw silica powder. Adjustment was made by changing the back.

The specific surface area and the average particle diameter of the amorphous silica powder are adjusted according to the particle size composition and the flame temperature of the raw silica powder, and the average sphericity and the amorphous rate of the amorphous silica powder are supplied to the flame and the temperature of the raw silica powder. And the like. In addition, LPG and oxygen gas were used for flame formation, and oxygen gas was also used for the carrier gas which conveys a raw material powder to a burner. The maximum temperature of this flame was in the range of about 2000 ° C to 2300 ° C.

Adsorption of pyridine to amorphous silica powder and measurement of the release temperature and the amount of release of pyridine from the amorphous silica powder were carried out by the method described in paragraph (0015).

The amorphous ratios of the obtained amorphous silica powder were all 99.5% or more. The specific surface area, average particle diameter, average sphericity, pyridine release temperature and the amount of release of these powders were measured, and the amount of pyridine leaving L in the heating of 450 ° C. or higher and less than 550 ° C., and the heating of 150 ° C. or higher and less than 250 ° C. Ratio of the release amount B of pyridine at and the total release amount B of pyridine at the heating of 150 ° C. or more and less than 250 ° C. in the total release amount A of pyridine at the heating of 150 ° C. or more and less than 550 ° C. The ratio (B / A) × 100% was calculated. The results are shown in Tables 3 and 4.

The characteristics as a filler of the semiconductor sealing material of the obtained amorphous silica powder and inorganic powder were evaluated. That is, 5.9 parts of biphenyl-type epoxy resins (YX-4000H by Japan Epoxy Resin Co., Ltd.), 5.1 parts of phenol aralkyl resins (XLC-LL by Mitsui Chemicals, Inc.) with respect to 87.8 parts (mass parts, the same below) of each powder, 0.2 parts of triphenylphosphine, 0.6 parts of epoxysilane coupling agent, 0.1 parts of carbon black and 0.3 parts of carnauba wax were added and dry blended with a Henschel mixer. Thereafter, the mixture was heated and kneaded with a coaxial twin-screw extrusion kneader (screw diameter D = 25 mm, kneading disc length 10 Dmm, puddle rotation speed 50 to 120 rpm, discharge amount 2.5 kg / hour, kneaded material temperature 99 to 100 ° C.). . The kneaded material (discharge) was pressed by a press machine, cooled, and then ground to prepare a semiconductor sealing material. The viscosity characteristics (curelastometer torque), moldability (wire strain) and fluidity (spiral flow) of the obtained semiconductor sealing material were evaluated as follows.

These results are shown in Table 3 and Table 4.

(1) Viscosity Characteristics (Cure Rheometer Torque)

The viscosity characteristic of the semiconductor sealing material obtained above was measured as follows. The torque after 30 second when the semiconductor sealing material was heated to 110 degreeC was used as the viscosity index using the cure rheometer (for example, JSR Trading Co., Ltd. brand name "cure rheometer model 3P-S type"). Smaller values indicate better viscosity characteristics.

(2) formability (wire strain)

The moldability of the semiconductor sealing material obtained above was measured as follows. Two simulated semiconductor elements having a size of 8 mm x 8 mm x 0.3 mm were superimposed on a substrate for a ball grid array (BGA) through a diamond touch film and connected with a gold wire. Thereafter, each semiconductor sealing material was used, and after the mold was molded into a package size of 38 mm x 38 mm x 1.0 mm using a transfer molding machine, it was post-cured at 175 ° C for 8 hours to prepare a BGA type semiconductor. The gold wire part of the semiconductor was observed with the soft X-ray transmission apparatus, and the gold wire strain was measured. The gold wire strain measured the wire shortest distance X before sealing and the wire maximum displacement amount Y after sealing, and calculated | required it as (Y / X) x 100 (%). This value was made into the average value of 12 gold wire strains. In addition, the diameter of a gold wire is (phi) 30micrometer, and an average length is 5 mm. Transfer molding conditions were the mold temperature of 175 degreeC, the molding pressure of 7.4 MPa, and the pressure holding time of 90 second. The smaller this value, the smaller the wire deformation amount, and the better the moldability.

(3) fluidity (spiral flow)

The spiral flow value of each semiconductor sealing material was measured using the transfer molding machine equipped with the spiral flow measuring mold based on EMMI-I-66 (Epoxy Molding Material Institute; Society of Plastic Industry). In addition, transfer molding conditions were made into the mold temperature of 175 degreeC, the molding pressure of 7.4 MPa, and the pressure holding time of 120 second. Larger values indicate better fluidity.

As apparent from the contrast between the examples and the comparative examples, according to the amorphous silica-like powder of the present invention, it is possible to produce a resin composition, in particular, a semiconductor sealing material, which has superior fluidity, viscosity characteristics, and moldability than the comparative examples.

The amorphous silica powder of the present invention is used as a filler for semiconductor sealing materials used in automobiles, portable electronic devices, personal computers, home telephone products, and the like, and laminates on which semiconductors are mounted. Moreover, the resin composition of this invention can be used as a prepreg for printed circuit boards, various engineer plastics, etc. which are made by impregnating and hardening a glass woven fabric, a glass nonwoven fabric, and other organic substrates other than a semiconductor sealing material.

In addition, the JP Patent application 2008-129122, the claim, and all the content of the abstract for which it applied on May 16, 2008 are referred here, and it introduces as an indication of the specification of this invention.

Claims (9)

After the pyridine is adsorbed to the amorphous silica powder, the ratio L / B of the amount of pyridine released at the time of heating at 450 ° C. or higher and less than 550 ° C. and the amount of pyridine at the temperature lower than 150 ° C. Is 0.8 or less, amorphous silica powder. 2. The pyridine release according to claim 1, wherein the pyridine is adsorbed to the amorphous silica-like powder, and then the pyridine is released at the heating of 150 ° C or more and less than 250 ° C, which accounts for the total amount A of pyridine at heating from 150 ° C or more and less than 550 ° C. The amorphous silica-like powder whose ratio (B / A) * 100% of quantity B is 20% or more. The amorphous silica-like powder according to claim 1 or 2, wherein the specific surface area is 0.5 to 45 m 2 / g, the average particle diameter is 0.1 to 60 µm, and the average sphericity is 0.80 or more. The inorganic powder containing the amorphous silica-like powder in any one of Claims 1-3. The inorganic powder according to claim 4, wherein the inorganic powder is an amorphous silica powder and / or an alumina powder other than the present invention. A mixture containing the raw silicate powder and the Al source material was sprayed into a flame formed by a burner to prepare an amorphous silicate powder, and then maintained for 15 to 30 minutes in an atmosphere having a temperature of 60 to 150 ° C and a relative humidity of 60 to 90%. The manufacturing method of the amorphous silica-like powder in any one of Claims 1-3 characterized by the above-mentioned. The resin composition containing the amorphous silica-like powder or inorganic powder in any one of Claims 1-5. The resin composition of Claim 7 whose resin of a resin composition is an epoxy resin. The semiconductor sealing material using the resin composition of Claim 7 or 8.