WO2015194552A1 - 窒化ケイ素粉末、窒化ケイ素焼結体及び回路基板、ならびに窒化ケイ素粉末の製造方法 - Google Patents
窒化ケイ素粉末、窒化ケイ素焼結体及び回路基板、ならびに窒化ケイ素粉末の製造方法 Download PDFInfo
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Definitions
- the present invention relates to a silicon nitride sintered body having a dense and high mechanical strength, in particular, a silicon nitride powder capable of obtaining a silicon nitride sintered body having both high thermal conductivity and high mechanical strength, and production of the silicon nitride powder. It is about the method.
- the present invention also relates to a silicon nitride sintered body having both high mechanical strength and high thermal conductivity, and a circuit board using the same.
- a silicon nitride sintered body obtained by molding and heat-sintering silicon nitride powder is excellent in mechanical strength, corrosion resistance, thermal shock resistance, thermal conductivity, electrical insulation, etc. It is used as a wear-resistant member such as a bearing, a high-temperature structural member such as an automobile engine part, and a circuit board. In applications such as circuit boards, there is a demand for a silicon nitride sintered body that achieves both high thermal conductivity and high mechanical strength, particularly at a level higher than conventional levels.
- the sintering aid is replaced with aluminum oxide and rare earth oxide, in which a sintered body with high mechanical strength is easily obtained, but the mechanical strength is hardly increased but the thermal conductivity is increased.
- magnesium oxide and rare earth oxide which can easily obtain a high-sintered sintered body, it is preferable to use silicon nitride powder with reduced impurity content or silicon nitride powder with adjusted oxygen content as a raw material. It is believed that.
- Patent Document 1 discloses a silicon nitride sintered body obtained by sintering silicon nitride powder having a ⁇ ratio of 93%, an Al content of 150 ppm, and an oxygen content of 0.9 mass%. Specifically, the example discloses a silicon nitride sintered body having a thermal conductivity of 95 to 118 W / m ⁇ K and a three-point bending strength of 660 to 900 MPa.
- Patent Document 2 sinters silicon nitride powder having an average particle diameter of 0.55 ⁇ m containing 1.1 mass% oxygen, 0.10 mass% impurity cations, and 97% ⁇ -phase silicon nitride.
- a silicon nitride sintered body obtained in this manner is disclosed.
- the example discloses a silicon nitride sintered body having a thermal conductivity of 50 to 130 W / m ⁇ K and a three-point bending strength of 600 to 850 MPa.
- Patent Document 3 discloses that an amorphous Si—N (—H) -based compound having a small oxygen content ratio with respect to a specific surface area is flowed in a continuous firing furnace, and is 12 to 100 ° C. in a temperature range of 1000 to 1400 ° C. Specific surface area of 5.6 to 28.9 m 2 / g, specific ratio of internal oxygen and surface oxygen, specific particle size distribution
- a silicon nitride sintered body obtained by sintering the silicon nitride powder is disclosed. Specifically, the example discloses a silicon nitride sintered body having a thermal conductivity of 130 to 142 W / m ⁇ K and a three-point bending strength of 605 to 660 MPa.
- Patent Document 4 has a particle size distribution in which d 10 , d 50 , and d 100 are 0.5 to 0.8 ⁇ m, 2.5 to 4.5 ⁇ m, and 7.5 to 10.0 ⁇ m, respectively, and oxygen.
- a silicon nitride powder having a content of 0.01 to 0.5 wt% is fired to have a thermal conductivity of 80 W / m. It is disclosed to produce a silicon nitride sintered body having a K-point, a three-point bending strength at room temperature of 600 MPa or more, and a fracture toughness of 5 MPa ⁇ m 1/2 .
- the three-point bending strength of the silicon nitride sintered body having the highest thermal conductivity of 118 W / m ⁇ K among Examples is relatively low at 800 MPa, while the highest three points of 900 MPa.
- the thermal conductivity of the silicon nitride sintered body having bending strength is as low as 96 W / m ⁇ K.
- the three-point bending strength of the silicon nitride sintered body having the highest thermal conductivity of 130 W / m ⁇ K among the examples is as low as 600 MPa, while the highest three-point bending strength at 850 MPa.
- the thermal conductivity of the silicon nitride sintered body having a low value is as low as 50 W / m ⁇ K.
- Patent Document 3 silicon nitride sintered bodies having a thermal conductivity of 130 to 142 W / m ⁇ K are disclosed, but their three-point bending strength is only 660 MPa even at the highest.
- Patent Document 4 discloses silicon nitride sintered bodies having a thermal conductivity of 105 to 115 W / m ⁇ K, but their three-point bending strength is only 750 MPa even at the highest.
- a silicon nitride sintered body having a thermal conductivity of, for example, 100 W / m ⁇ K or more can be obtained by adjusting the content of oxygen-containing impurities in the silicon nitride powder as a raw material.
- a silicon nitride sintered body having a high thermal conductivity has a relatively low mechanical strength.
- the main object of the present invention is to provide a silicon nitride sintered body having high thermal conductivity and also having high mechanical strength, a circuit board using the silicon nitride sintered body, and the silicon nitride sintered body.
- the object is to provide a silicon nitride powder as a raw material and a method for producing the silicon nitride powder.
- the present invention has a specific surface area of 4.0 to 9.0 m 2 / g, a ⁇ phase ratio of less than 40%, an oxygen content of 0.20 to 0.95 mass%, and laser diffraction.
- the frequency distribution curve obtained by the volume-based particle size distribution measurement by the scattering method has two peaks, and the peak top of the peak is in the range of 0.4 to 0.7 ⁇ m and 1.5 to 3.0.
- the ratio of the frequency of peak tops (the frequency of peak tops in the range of particle diameters of 0.4 to 0.7 ⁇ m / frequency of peak tops in the range of particle diameters of 1.5 to 3.0 ⁇ m) is 0.5.
- a ratio ⁇ Dp / D50 calculated by dividing a difference ⁇ Dp ( ⁇ m) by a median diameter D50 ( ⁇ m) is 1.10 or more.
- the silicon nitride powder is characterized in that the proportion of ⁇ phase is 5 to 35% by mass.
- the minimum value of the particle size obtained by the particle size distribution measurement is in the range of 0.10 to 0.30 ⁇ m, and the maximum value of the particle size obtained by the particle size distribution measurement is 6 to 30 ⁇ m. It is related with the said silicon nitride powder characterized by being in the range.
- the present invention also relates to a silicon nitride sintered body obtained by sintering the silicon nitride powder.
- the present invention relates to a silicon nitride sintered body characterized by containing magnesium oxide and yttrium oxide as a sintering aid for the silicon nitride powder.
- the preferred embodiment of the present invention relates to a silicon nitride sintered body having a room temperature (25 ° C.) thermal conductivity of 100 W / m ⁇ K or more and a room temperature (25 ° C.) three-point bending strength of 900 MPa or more.
- the present invention relates to a circuit board using the silicon nitride sintered body.
- an amorphous Si—N (—H) compound having a specific surface area of 300 to 800 m 2 / g is accommodated in a crucible, and the amorphous Si—N (—H) compound is flowed.
- the oxygen content of the compound is 0.15 to 0.50 mass%
- the amorphous Si—N (—H) compound is 250 to 1000 ° C./hour in the temperature range of 1000 to 1400 ° C. during the firing. It is related with the manufacturing method of the silicon nitride powder characterized by heating at the temperature increase rate of.
- the silicon nitride powder obtained by crushing the silicon nitride powder obtained by the firing without pulverization has a specific surface area of 4.0 to 9.0 m 2 / g.
- the ratio of ⁇ phase is less than 40% by mass
- the oxygen content is 0.20 to 0.95% by mass
- the frequency distribution curve obtained by volume-based particle size distribution measurement by laser diffraction scattering method has two frequency distribution curves.
- a peak top of the peak is in the range of 0.4 to 0.7 ⁇ m and 1.5 to 3.0 ⁇ m, and the ratio of the frequency of the peak tops (particle diameter 0.4 to 0
- the frequency of peak top in the range of 0.7 ⁇ m / frequency of peak top in the range of 1.5 to 3.0 ⁇ m) is 0.5 to 1.5
- the specific surface area equivalent diameter calculated from the specific surface area The method for producing a silicon nitride powder wherein a ratio D50 / D BET and BET ( ⁇ m) ( ⁇ m / ⁇ m ) is 3.5 or more.
- a silicon nitride sintered body having a dense and excellent mechanical strength and a high thermal conductivity is provided. According to the present invention, it is possible to provide a silicon nitride sintered body having a high three-point bending strength of 900 MPa or more at room temperature while having a high thermal conductivity of 100 W / m ⁇ K or more at room temperature.
- a circuit board having both excellent mechanical strength and high thermal conductivity is provided.
- a powder can be provided.
- the cross section of a circuit board is shown typically. It is a figure which shows the frequency distribution curve obtained by the volume reference
- FIG. 1 shows the frequency distribution curve obtained by the volume reference
- the silicon nitride powder according to the present invention is a novel silicon nitride powder capable of obtaining a silicon nitride sintered body having both high mechanical properties and high thermal conductivity that cannot be obtained by the prior art.
- the silicon nitride powder according to the present invention will be described.
- the silicon nitride powder according to the present invention has a specific surface area of 4.0 to 9.0 m 2 / g, a ⁇ phase ratio of less than 40% by mass, and an oxygen content of 0.20 to 0.95% by mass.
- a frequency distribution curve obtained by volume-based particle size distribution measurement by a laser diffraction scattering method (hereinafter sometimes referred to as a frequency distribution curve of particle size distribution) has two peaks, and the peak top of the peak is 0.
- the ratio of the peak top frequencies (the frequency of peak tops in the range of particle diameters of 0.4 to 0.7 ⁇ m / particle diameters of 1. to 0.7 ⁇ m and 1.5 to 3.0).
- the frequency of the peak top in the range of 5 to 3.0 ⁇ m) is 0.5 to 1.5, and the specific surface area equivalent diameter D calculated from the median diameter D50 ( ⁇ m) obtained by the particle size distribution measurement and the specific surface area.
- the ratio D50 / D BET ⁇ m between BET ([mu] m) [mu] m) is silicon nitride powder, characterized in that at least 3.5.
- the ratio of the frequency of peak tops (the frequency of peak tops in the range of particle diameters of 0.4 to 0.7 ⁇ m / frequency of peak tops in the range of particle diameters of 1.5 to 3.0 ⁇ m), Sometimes referred to as peak top frequency ratio.
- the specific surface area of the silicon nitride powder according to the present invention is in the range of 4.0 to 9.0 m 2 / g.
- the specific surface area is less than 4.0 m 2 / g, the surface energy of the particles becomes small. Such powders are difficult to sinter, and the strength and thermal conductivity of the resulting sintered body tend to be low.
- the specific surface area exceeds 9.0 m 2 / g, the surface energy of the particles becomes large and it becomes easy to sinter, and further, since the oxygen content is high, it becomes easier to sinter, but the ⁇ -phase columnar particles in the sintered body When abnormal grains grow or become fine grains, the relative density of the obtained sintered body tends to be non-uniform.
- the obtained sintered body is not uniformly densified and high mechanical properties cannot be obtained. Therefore, in order to obtain a silicon nitride sintered body having both high mechanical strength and high thermal conductivity, the specific surface area of the raw material silicon nitride powder must be in the range of 4.0 to 9.0 m 2 / g. It becomes. The range is preferably from 5.0 to 8.0 m 2 / g.
- the proportion of the ⁇ phase of the silicon nitride powder according to the present invention is less than 40% by mass.
- the proportion of the ⁇ phase is smaller than 40% by mass, the densification rate at the time of sintering is increased by promoting the columnar particle formation of the ⁇ phase at the time of recrystallization in the sintering process.
- the proportion of ⁇ phase is 40% by mass or more, the obtained sintered body is difficult to be densified, and silicon nitride having both high mechanical strength and high thermal conductivity cannot be obtained.
- the proportion of ⁇ phase is preferably 5 to 35% by mass. If it is this range, the sintered compact obtained will be especially easy to densify.
- the phases other than the ⁇ phase of the silicon nitride powder according to the present invention are basically composed of an ⁇ phase, and in a preferred embodiment, all of the phases are composed of an ⁇ phase and a ⁇ phase.
- amorphous silicon nitride or the like other than the ⁇ phase and the ⁇ phase can be contained in an amount of 2.0% by mass or less, more preferably 1.5% by mass or less.
- Methods for measuring the proportion of ⁇ phase in silicon nitride powder are known. For example, components other than silicon nitride can be obtained by composition analysis, and the ratio of ⁇ phase and ⁇ phase of silicon nitride can be measured by the method described in the examples.
- the ratio of amorphous silicon nitride can be measured by the nitrogen amount of NH 3 gas generated by the decomposition of amorphous silicon nitride as follows. A precisely weighed silicon nitride powder is added to 1.0N NaOH aqueous solution, heated and boiled to decompose only amorphous silicon nitride, and NH 3 gas generated thereby is absorbed in 1% boric acid aqueous solution. The amount of NH 3 in the solution is titrated with a 0.1N sulfuric acid standard solution. Then, the amount of nitrogen generated by decomposition from the amount of NH 3 in the absorbing liquid (the amount of decomposed nitrogen) is calculated.
- the ratio of amorphous silicon nitride can be calculated by the following formula (1) from the amount of decomposed nitrogen per gram of sample and the theoretical nitrogen amount of silicon nitride of 39.94%.
- Ratio of amorphous silicon nitride (mass%) decomposed nitrogen amount per 1 g of sample (g) ⁇ 100 / 39.94 (1)
- the oxygen content of the silicon nitride powder according to the present invention is 0.20 to 0.95 mass%. If the oxygen content is less than 0.20% by mass, the silicon nitride sintered body is difficult to be densified. Therefore, a dense silicon nitride sintered body cannot be obtained unless the addition amount of the sintering aid is increased. When the amount of the sintering aid added is large, the thermal conductivity does not increase, so that a silicon nitride sintered body having both high mechanical strength and thermal conductivity cannot be obtained.
- the oxygen content of the silicon nitride powder is preferably 0.20 to 0.95% by mass.
- the frequency distribution curve obtained by volume-based particle size distribution measurement by the laser diffraction scattering method has two peaks, and the particle diameter at the peak top of the peak is 0.4-0.
- the ratio of the frequency of peak tops (the frequency of peak tops in the range of particle diameters of 0.4 to 0.7 ⁇ m / particle diameters of 1.5 to 3) is in the range of 0.7 ⁇ m and 1.5 to 3.0 ⁇ m.
- Peak top frequency in the range of .mu.m is 0.5 to 1.5.
- the peak top frequency ratio is preferably 0.5 to 1.2.
- the frequency distribution curve obtained by the particle size distribution measurement has only one peak, since the obtained silicon nitride sintered body is difficult to be densified, the mechanical strength and the thermal conductivity are hardly increased, and the high mechanical strength is obtained. And a silicon nitride sintered body having high thermal conductivity cannot be obtained.
- the frequency distribution curve obtained by the particle size distribution measurement has two peaks, and the particle diameter of the peak top having the smaller particle diameter is smaller than 0.4 ⁇ m, the sintering process
- the silicon nitride particles having a small particle diameter are taken into the relatively large silicon nitride particles and the ⁇ -phase grain growth is promoted, so that the ratio of coarse columnar particles in the particles constituting the sintered body is increased.
- the mechanical strength of the obtained silicon nitride sintered body is lowered.
- the frequency distribution curve obtained by the particle size distribution measurement has two peaks, and when the particle diameter of the peak top having the larger particle diameter is larger than 3.0 ⁇ m among those peaks, sintering is performed. Therefore, the resulting silicon nitride sintered body has low mechanical strength and thermal conductivity.
- the frequency distribution curve obtained by the particle size distribution measurement has two peaks, and the particle diameter of one or both of the two peak tops of those peaks is between 0.7 ⁇ m and 1.5 ⁇ m. Since the molding density is difficult to increase, the obtained silicon nitride sintered body is difficult to be densified, and its mechanical strength and thermal conductivity are lowered.
- Ratio of peak top frequencies of two peaks in the frequency distribution curve of particle size distribution (peak top frequency in the range of particle diameter 0.4 to 0.7 ⁇ m / peak top frequency in the range of particle diameter 1.5 to 3.0 ⁇ m) If the frequency) is less than 0.5 or greater than 1.5, the resulting silicon nitride sintered body is difficult to be densified, and its mechanical strength and thermal conductivity are low.
- the silicon nitride powder according to the present invention has a minimum particle size obtained by particle size distribution measurement obtained by volume-based particle size distribution measurement by a laser diffraction scattering method in the range of 0.10 to 0.30 ⁇ m, and the particle size distribution
- the maximum particle diameter obtained by measurement is preferably in the range of 6 to 30 ⁇ m. If the minimum and maximum particle diameters are within this range, the density during molding can be increased and the resulting silicon nitride sintered body can be easily densified. Since the uniformity of the structure becomes high, it is possible to obtain a silicon nitride sintered body having both particularly high mechanical strength and heat conductivity.
- the silicon nitride powder according to the present invention has a median diameter D50 ( ⁇ m) obtained by particle size distribution measurement obtained by volume-based particle size distribution measurement by the laser diffraction scattering method and a specific surface area equivalent diameter D calculated from the specific surface area.
- D50 ⁇ m
- D BET [mu] m) ratio of D50 / D BET ( ⁇ m / ⁇ m ) is 3.5 or more.
- the median diameter D50 refers to the particle diameter when the volume accumulated from the smaller particle diameter to the larger particle diameter distribution in the volume basis is 50% of the total volume
- D BET is the BET described above.
- the diameter (particle diameter) of a particle calculated by assuming that the silicon nitride powder is spherical from the specific surface area of the silicon nitride powder measured by the method.
- D50 / D BET ( ⁇ m / ⁇ m) is less than 3.5, it is difficult to obtain a silicon nitride sintered body having both high mechanical strength and thermal conductivity.
- the D50 / D BET ( ⁇ m / ⁇ m) of the silicon nitride powder according to the present invention is preferably 10 or less. If D50 / D BET ( ⁇ m / ⁇ m) is 10 or less, warpage and deformation of the obtained silicon nitride sintered body are reduced.
- the lower limit value of D50 / D BET ( ⁇ m / ⁇ m) is preferably 4 . If the D50 / D BET value is 4 or more, a silicon nitride sintered body having particularly high mechanical strength and thermal conductivity is easily obtained.
- the silicon nitride powder according to the present invention has a peak top particle size ( ⁇ m) in the range of 1.5 to 3.0 ⁇ m and a peak top particle size in the range of 0.4 to 0.7 ⁇ m. It is preferable that the ratio ⁇ Dp / D50 of the difference ⁇ Dp in the particle diameter ( ⁇ m) of each peak top to the median diameter D50 calculated by dividing the difference from ( ⁇ m) by D50 ( ⁇ m) is 1.10 or more. . This is because if this is 1.10 or more, it is easy to obtain a sintered body having a particularly high thermal conductivity.
- the upper limit value of ⁇ Dp / D50 is preferably 3. When ⁇ Dp / D50 is 3 or less, the obtained silicon nitride sintered body is particularly easily densified, and a silicon nitride sintered body having both high mechanical strength and thermal conductivity is particularly easily obtained.
- the silicon nitride powder according to the present invention is a silicon nitride powder having a specific surface area of 4.0 to 9.0 m 2 / g and a ⁇ phase ratio of less than 40% by mass, and having an oxygen content of 0.20 to
- the frequency distribution curve obtained by volume-based particle size distribution measurement by laser diffraction scattering method has 0.95 mass% and has two peaks, and the peak top of the peak is in the range of 0.4 to 0.7 ⁇ m.
- the ratio of the frequency of peak tops (the frequency of peak tops in the range of particle diameters of 0.4 to 0.7 ⁇ m / range of particle diameters of 1.5 to 3.0 ⁇ m).
- the ratio of the median diameter D50 ( ⁇ m) obtained by particle size distribution measurement to the specific surface area equivalent diameter D BET ( ⁇ m) calculated from the specific surface area is 0.5 to 1.5.
- D50 / D BET ( ⁇ m / ⁇ m ) of 3.5 or more der Characterized in that, there novel silicon nitride powder, it is suitable as a raw material of sintered silicon nitride having both high mechanical strength and high thermal conductivity.
- a silicon nitride sintered body having a high three-point bending strength of 900 MPa or more at room temperature while having a high thermal conductivity of 100 W / m ⁇ K or more at room temperature is provided. can do.
- silicon nitride sintered body and circuit board using the same Next, the silicon nitride sintered body according to the present invention and a circuit board using the same will be described.
- the silicon nitride sintered body according to the present invention is manufactured by the following manufacturing method.
- the silicon nitride powder and the sintering aid according to the present invention By mixing the silicon nitride powder and the sintering aid according to the present invention, forming the obtained mixed powder, and further sintering the obtained molded body, the high mechanical strength and high heat according to the present invention are obtained.
- a silicon nitride sintered body having both conductivity can be produced.
- a silicon nitride sintered body having both high mechanical strength and high thermal conductivity according to the present invention can be produced while simultaneously performing molding and sintering.
- the silicon nitride sintered body according to the present invention has a high thermal conductivity of 100 W / m ⁇ K or more at room temperature, more preferably 105 W / m ⁇ K or more, and even more preferably 110 W / m ⁇ K or more.
- sintering aids such as yttrium oxide, lanthanoid rare earth oxide, and magnesium oxide can be used alone or in appropriate combination depending on the purpose.
- magnesium compounds such as MgSiN 2 and Mg 2 Si, titanium oxide, zirconium oxide, lithium oxide, boron oxide, calcium oxide, etc. alone or yttrium oxide, lanthanoid rare earth oxide, magnesium oxide, etc. Can be used in combination with at least one of the above.
- the silicon nitride sintered body according to the present invention is preferably a sintered body obtained by sintering the silicon nitride powder according to the present invention using a powder comprising magnesium oxide and yttrium oxide as a sintering aid. This is because high strength and high thermal conductivity can be achieved at a particularly high level.
- the amount of the sintering aid added depends on the type of the sintering aid, but is generally 1.0 to 10.0% by mass based on the total of the silicon nitride particles and the sintering aid. Is preferably 1.5 to 7.0% by mass.
- a kind of sintering aid one or two kinds selected from magnesium oxide and Ca, Sr, Ba, Y, La, Ce, Pr, Nd, Sm, Gd, Dy, Ho, Er, and Yb. Combinations with the oxides of the above elements are preferred.
- magnesium oxide and yttrium oxide are preferably 0.5 to 2.5 mass% and 1.0 to 4.5 mass%, respectively, and 1.5 to 7.0 mass% in total.
- any method can be used regardless of whether it is a wet type or a dry type as long as these can be mixed uniformly, and known methods such as a rotary mill, a barrel mill, and a vibration mill are known.
- This method can be used.
- CIP cold isostatic pressing
- any method may be used as long as the obtained sintered body is densified, but nitrogen, or atmospheric pressure sintering in an inert gas atmosphere such as argon mixed with nitrogen, or Further, gas pressure sintering is employed in which the gas pressure in an inert gas atmosphere such as nitrogen or nitrogen mixed with nitrogen is increased to about 0.2 to 10 MPa.
- the sintering may be performed using nitrogen gas in a temperature range of 1700 to 1800 ° C. for atmospheric pressure sintering and 1800 to 2000 ° C. for gas pressure sintering.
- a hot press which is a method of simultaneously performing molding and sintering.
- Sintering by hot pressing may be usually performed in a nitrogen atmosphere at a pressure of 0.2 to 10 MPa and a sintering temperature of 1950 to 2050 ° C.
- the strength can be further improved by subjecting the obtained silicon nitride sintered body to HIP (hot isostatic pressing) treatment.
- HIP treatment may be usually performed in a nitrogen atmosphere at a pressure of 30 to 200 MPa and a sintering temperature of 2100 to 2200 ° C.
- the obtained silicon nitride sintered body preferably has a relative density of 96% or more, and more preferably 97% or more and 98% or more.
- the relative density of the silicon nitride sintered body is the density of the silicon nitride sintered body expressed as a percentage relative to the true density of silicon nitride. If the relative density is low, it is difficult to increase the mechanical strength.
- the circuit board according to the present invention can be manufactured by the following method.
- the circuit board is a plate-like component having an electronic circuit formed on the surface or a component (not including an electronic circuit) for forming an electronic circuit on the surface.
- FIG. 1 schematically shows a cross section of a circuit board.
- an electronic circuit 2 or a conductive material layer 2 for forming an electronic circuit is provided on the surface of a plate-like substrate 1 made of a silicon nitride sintered body.
- the circuit board according to the present invention is obtained by processing the silicon nitride sintered body according to the present invention into a plate shape by grinding or the like, joining a metal sheet or the like to the obtained plate-like sintered body, and then etching the metal sheet. It can be manufactured by removing a part and forming a conductor circuit pattern on the surface of the plate-like sintered body.
- a raw material mixture is prepared by adding a sintering aid, an organic binder and the like to the silicon nitride powder according to the present invention, and then the obtained raw material mixture is formed by a sheet forming method such as a doctor blade method ( Green sheet). Thereafter, a conductor forming paste is screen-printed on the surface of the molded body to form a conductor circuit pattern having a predetermined shape.
- the circuit board according to the present invention can be manufactured by removing the organic binder by degreasing treatment and firing the molded body on which the obtained pattern is formed in an inert atmosphere.
- the silicon nitride powder according to the present invention contains an amorphous Si—N (—H) compound having a specific surface area of 300 to 800 m 2 / g and an oxygen content of 0.15 to 0.50 mass% in a crucible. Then, in a nitrogen-containing inert gas atmosphere or a nitrogen-containing reducing gas atmosphere, heating is performed at a temperature rising rate of 250 to 1000 ° C./hour in a temperature range of 1000 to 1400 ° C., and firing is performed at a temperature of 1400 to 1700 ° C. It can manufacture preferably.
- Method for producing amorphous Si—N (—H) compound A method for producing an amorphous Si—N (—H) -based compound that can be used as a raw material for producing the silicon nitride powder according to the present invention will be described.
- a crystalline silicon nitride powder can be produced by firing an amorphous Si—N (—H) compound.
- the amorphous Si—N (—H) compound used in the present invention is Si obtained by thermally decomposing part or all of a nitrogen-containing silane compound such as silicon diimide, silicon tetraamide, silicon chlorimide, An amorphous Si—N (—H) compound containing each element of N and H, or an amorphous silicon nitride containing Si and N, represented by the following composition formula (1) .
- the amorphous Si—N (—H) compound is composed of oxygen contained in the raw material nitrogen-containing silane compound and / or oxygen derived from oxygen in the atmosphere when the nitrogen-containing silane compound is thermally decomposed. Can be contained.
- the nitrogen-containing silane compound in the present invention silicon diimide, silicon tetraamide, silicon chlorimide and the like are used. These compounds are represented by the following composition formula (3).
- the nitrogen-containing silane compound is derived from oxygen derived from oxygen in the atmosphere when the nitrogen-containing silane compound is synthesized in a gas phase, or from water contained in the reaction solvent during the liquid-phase synthesis of the nitrogen-containing silane compound. It can contain oxygen.
- the amorphous Si—N (—H) compound in the present invention can be produced by a known method.
- the nitrogen-containing silane compound is thermally decomposed at a temperature of 1200 ° C. or less in a nitrogen or ammonia gas atmosphere.
- the specific surface area of the amorphous Si—N (—H) compound used for producing the silicon nitride particles according to the present invention is preferably 300 to 800 m 2 / g. If the specific surface area of the amorphous Si—N (—H) compound is in this range, the silicon nitride powder obtained is easy to control the crystallization reaction of silicon nitride at an appropriate rate during firing. It is easy to adjust the specific surface area in the range of 4.0 to 9.0 m 2 / g.
- the specific surface area of the amorphous Si—N (—H) compound is smaller than 300 m 2 / g, a very rapid crystallization reaction occurs in the temperature range of 1000 to 1400 ° C., particularly 1100 to 1250 ° C. during firing. As a result, the proportion of particles having a small particle size increases, and particularly particles having a small particle size are generated. Therefore, the specific surface area of the obtained silicon nitride powder tends to be large, and the minimum value of the particle size tends to be small. In addition, the obtained silicon nitride powder tends to have a single peak in the frequency distribution curve obtained by volume-based particle size distribution measurement by laser diffraction scattering method, with a peak top in a relatively small particle diameter range. .
- the obtained silicon nitride sintered body is difficult to be densified, and mechanical strength and thermal conductivity are hardly increased. Moreover, the crystallization exothermic damage to the firing container used in the batch furnace and the pusher is large, which may cause the manufacturing cost to deteriorate.
- the specific surface area of the amorphous Si—N (—H) compound is larger than 800 m 2 / g, the crystallization reaction proceeds slowly, so that the obtained silicon nitride powder has a large particle diameter.
- the ratio tends to be large, and the specific surface area tends to be smaller than 4.0 m 2 / g.
- the frequency distribution curve of the particle size distribution has only one peak in the range where the particle diameter is large or has two peaks, the particle diameter of the peak top with the larger particle diameter is larger than 3.0 ⁇ m. Prone. Even if such silicon nitride powder is sintered, the obtained silicon nitride sintered body is difficult to be densified, and mechanical strength and thermal conductivity are hardly increased.
- the specific surface area of the amorphous Si—N (—H) compound is larger than 800 m 2 / g, the oxidation easily proceeds even in an atmosphere containing a slight amount of oxygen or moisture. It is difficult to adjust the oxygen content of the (—H) compound.
- the specific surface area of the amorphous Si—N (—H) compound can be adjusted by the specific surface area of the nitrogen-containing silane compound as a raw material and the maximum temperature when the nitrogen-containing silane compound is thermally decomposed.
- the specific surface area of the amorphous Si—N (—H) compound can be increased as the specific surface area of the nitrogen-containing silane compound is increased and the maximum temperature during the thermal decomposition is decreased.
- the nitrogen-containing silane compound is silicon diimide
- the specific surface area of the nitrogen-containing silane compound is, for example, a known method shown in Patent Document 5, that is, silicon halide and liquid when reacting silicon halide and liquid ammonia. It can be adjusted by a method of changing the ratio with ammonia (silicon halide / liquid ammonia (volume ratio)).
- the specific surface area of the nitrogen-containing silane compound can be increased by increasing the silicon halide / liquid ammonia.
- the oxygen content of the amorphous Si—N (—H) compound used for producing the silicon nitride particles of the present invention is preferably 0.15 to 0.50 mass%.
- the resulting silicon nitride powder tends to have a small primary particle in addition to an increase in the oxygen content.
- the specific surface area tends to be larger than 9.0 m 2 / g.
- the proportion of ⁇ phase tends to be small.
- the frequency distribution curve of the particle size distribution tends to have only one peak with a peak top in a range where the particle diameter is smaller than 0.4 ⁇ m.
- the amorphous Si—N (—H) compound is heated in the temperature range of 1000 to 1400 ° C. while flowing.
- the resulting silicon nitride powder When fired at a high temperature rate, the resulting silicon nitride powder tends to have a larger proportion of particles with small primary particles, and some of them may fuse to form relatively large particles.
- the frequency distribution curve of the particle size distribution may have two peaks, but the particle diameter of the peak top having a larger particle diameter tends to be larger than 3.0 ⁇ m.
- the obtained silicon nitride powder tends to have an oxygen content larger than 0.95 mass%. Even if such silicon nitride powder is sintered, the obtained silicon nitride sintered body is difficult to be densified, and even if it can be densified, the mechanical strength of the sintered body tends to be low. In addition, since the oxygen content is large, the thermal conductivity is hardly increased.
- the oxygen content of the amorphous Si—N (—H) compound according to the present invention is less than 0.15% by mass, the resulting silicon nitride powder has a reduced oxygen content, Primary particles tend to be large, and the specific surface area tends to be smaller than 4.0 m 2 / g. Also, the proportion of ⁇ phase tends to increase. Further, the frequency distribution curve of the particle size distribution tends to have only one peak with a peak top in a range where the particle diameter is larger than 0.7 ⁇ m. When an amorphous Si—N (—H) compound having a relatively large specific surface area is used as a raw material, some of the resulting silicon nitride powder may be coarsened.
- the distribution curve may have two peaks, but the peak top with the larger particle diameter is larger than 3.0 ⁇ m. Moreover, the obtained silicon nitride powder tends to have a low oxygen content. Even if such silicon nitride powder is sintered, the resulting silicon nitride sintered body is difficult to be densified, and neither mechanical strength nor thermal conductivity is increased.
- the oxygen content of the amorphous Si—N (—H) compound is determined by the oxygen content of the nitrogen-containing silane compound and the oxygen partial pressure (oxygen concentration) and / or flow rate in the atmosphere when the nitrogen-containing silane compound is thermally decomposed. It can be adjusted by controlling. The lower the oxygen content of the nitrogen-containing silane compound and the lower the oxygen partial pressure and / or flow rate in the atmosphere during the thermal decomposition, the lower the oxygen content of the amorphous Si—N (—H) compound. can do. Further, the oxygen content of the amorphous Si—N (—H) compound is increased as the oxygen content of the nitrogen-containing silane compound is increased, and as the oxygen partial pressure and / or flow rate in the atmosphere during the thermal decomposition is increased.
- the oxygen content of the nitrogen-containing silane compound is such that when a halogenated silicon such as silicon tetrachloride, silicon tetrabromide or silicon tetraiodide is reacted in the gas phase, the oxygen concentration in the atmospheric gas at the time of the reaction.
- a halogenated silicon such as silicon tetrachloride, silicon tetrabromide or silicon tetraiodide
- the amount of water in an organic reaction solvent such as toluene can be controlled.
- the oxygen content of the nitrogen-containing silane compound can be lowered as the water content in the organic reaction solvent is decreased, and the oxygen content of the nitrogen-containing silane compound can be increased as the water content in the organic reaction solvent is increased. it can.
- the silicon nitride powder according to the present invention contains an amorphous Si—N (—H) compound having a specific surface area of 300 to 800 m 2 / g and an oxygen content of 0.15 to 0.50 mass% in a crucible. Then, the amorphous Si—N (—H) compound can be obtained without flowing the amorphous Si—N (—H) compound in a nitrogen-containing inert gas atmosphere or a nitrogen-containing reducing gas atmosphere. Can be produced by heating at a temperature rising rate of 250 to 1000 ° C./hour in a temperature range of 1000 to 1400 ° C. and firing at a holding temperature of 1400 to 1700 ° C.
- the amorphous Si—N (—H) compound obtained by the above-mentioned method (a part or all of the nitrogen-containing silane compound is thermally decomposed) is not pulverized but pulverized.
- a crushed amorphous Si—N (—H) compound can be preferably used.
- the amorphous Si—N (—H) -based compound obtained can be used in the method for producing a silicon nitride powder according to the present invention only by crushing without being pulverized and classified. It can have characteristics such as specific surface area and oxygen content required for a high-quality Si—N (—H) compound.
- the particles are only crushed without being pulverized, the acquisition cost is reduced and foreign particles such as metals and resins are prevented from being mixed into the particles.
- the inclusion of foreign matter in the final silicon nitride powder tends to be a starting point for fracture of the sintered body and may reduce the mechanical strength of the sintered body. It is preferable that at least a part of the crushed amorphous Si—N (—H) -based compound is formed into granules and then placed in a crucible and fired.
- the amorphous Si—N (—H) -based compound By crushing the amorphous Si—N (—H) -based compound, forming at least a part of the amorphous Si-N (—H) compound into a granule, and firing it, the formation of acicular crystal particles and fine particles is easily suppressed. As a result, the minimum value of the particle diameter becomes relatively large, and the ratio of the granular particles becomes relatively large, so that it becomes easy to obtain a silicon nitride powder capable of further increasing the density of the sintered body. In addition, the packing density of the amorphous Si—N (—H) compound in the crucible can be easily adjusted.
- the crushing is preferably performed so that aggregated particles exceeding 50 ⁇ m do not remain in the amorphous Si—N (—H) -based compound before molding, and so that aggregated particles exceeding 30 ⁇ m do not remain.
- the crushing of the amorphous Si—N (—H) compound is different from the crushing for the purpose of breaking the primary particles, and is a treatment performed for the purpose of releasing the agglomeration or aggregation of relatively large agglomerated particles. That is.
- the amorphous Si—N (—H) -based compound is accommodated in a pot together with the ball and the vibration ball mill treatment is performed.
- the vibration ball mill treatment it is preferable to use a pot whose inner wall surface is lined with a resin, a ball lined with a resin, or a ball made of a silicon nitride sintered body. Further, the crushing of the amorphous Si—N (—H) compound is performed in an inert gas atmosphere such as a nitrogen atmosphere in order to suppress oxidation of the amorphous Si—N (—H) compound. It is preferable.
- batch-type vibration ball mill treatment is performed in which the powder before pulverization is accommodated in a pot for processing, and continuous treatment is performed while the powder before pulverization is continuously fed from the feeder into the pot. Any of vibration ball mill processing may be employed. Either batch type or continuous type vibration ball mill processing may be selected in accordance with the processing amount.
- a briquette machine BGS-IV manufactured by Shinto Kogyo Co., Ltd. is used in a nitrogen atmosphere under a nitrogen atmosphere.
- it is formed into an almond shape having a thickness of 6 mm, a short axis diameter of 8 mm, a long axis diameter of 12 mm, a thickness of 8 mm, a short axis diameter of 12 mm, and a long axis diameter of 18 mm. It is preferable to do.
- the apparent density of the granular shaped product of the amorphous Si—N (—H) compound is measured by Archimedes method using normal hexane as the immersion liquid.
- the amorphous Si—N (—H) compound to be fired is transferred to the crucible. It becomes easy to adjust the packing density.
- the amorphous Si—N (—H) compound according to the present invention is contained in a crucible and fired without flowing the amorphous Si—N (—H) compound.
- -H) The compound is placed in a crucible and the amorphous Si-N (-H) compound is allowed to stand in the crucible and fired using a batch furnace, a pusher type continuous furnace, or the like. It is distinguished from firing with flowing an amorphous Si—N (—H) compound using a rotary kiln furnace or the like. That is, the crucible containing the amorphous Si—N (—H) compound may be allowed to stand or move in the heating furnace, but the amorphous Si—N (—H) compound may be static in the crucible. It is placed and does not flow.
- the resulting silicon nitride powder has a frequency distribution curve obtained by particle size distribution measurement, the particle size of which is Even if there is only one peak in a relatively small range or has two peaks, the frequency of the peak top with the larger particle diameter becomes smaller, and the ratio of the peak top frequencies (particle diameter of 0.4 to The frequency of the peak top in the range of 0.7 ⁇ m / the frequency of the peak top in the range of the particle diameter of 1.5 to 3.0 ⁇ m) tends to be larger than 1.5. Even if such silicon nitride powder is sintered, it is difficult to obtain a silicon nitride sintered body having high mechanical strength and high thermal conductivity according to the present invention.
- the crucible used for firing the amorphous Si—N (—H) compound is not particularly limited, but the side or diameter of the bottom surface of the crucible is 15 mm or more and the inner dimension is 150 mm or more. It is preferable to use a crucible having For example, a box-type (bottomed square tube-shaped) crucible having a bottom side of 15 mm or more and a height of 150 mm or more, or a bottom type inner diameter of 15 mm or more and a height of 150 mm or more. It is preferable to use a cylindrical crucible or the like.
- a box-shaped crucible having a bottom side of 150 mm or more which is partitioned by a grid plate so that the inside has a spacing of 15 mm or more, or a concentric shape so that the inside has a spacing of 15 mm or more.
- a bottomed cylindrical crucible or the like that is partitioned by the arranged cylinder and has an inner diameter of the bottom surface of 150 mm or more.
- the crucible is preferably not too large, and it is preferable to use a crucible having an inner dimension of one side or inner diameter of 400 mm or less and a height of 600 mm or less.
- the amorphous Si—N (—H) -based compound is not particularly limited, but it is preferable that the amorphous Si—N (—H) compound is accommodated in a crucible at a filling density of 0.10 to 0.55 g / mL and fired.
- the packing density can be easily adjusted by the proportion of the amorphous Si—N (—H) -based compound granular molded product.
- the proportion of the granular molded product is 50% by mass or more, and the packing density is zero. It is preferably 25 to 0.50 g / mL.
- the maximum temperature during firing is in the range of 1400-1700 ° C.
- the firing temperature is lower than 1400 ° C.
- the ratio of ⁇ phase of the obtained silicon nitride powder tends to be small.
- the crystallinity may be lowered.
- the firing temperature is higher than 1700 ° C.
- the resulting silicon nitride powder has a large proportion of fused particles, and the frequency distribution curve obtained by particle size distribution measurement has a peak top in a range larger than 3.0 ⁇ m. May be included.
- the firing temperature exceeds 1750 ° C., decomposition of the silicon nitride powder starts.
- the firing temperature is not limited as long as it is in the range of 1400 to 1700 ° C., but is preferably in the range of 1400 to 1600 ° C., more preferably 1450 to 1550 ° C.
- the maximum temperature (or firing temperature) during firing is preferably maintained for 0.25 hours or more, more preferably 0.25 to 2.0 hours.
- the above amorphous Si—N (—H) compound is placed in a crucible and heated at a temperature rising rate of 250 to 1000 ° C./hour in a temperature range of 1000 to 1400 ° C. to be fired.
- the heating rate in the temperature range of 1000 to 1400 ° C. is preferably 300 to 900 ° C./hour.
- the obtained silicon nitride powder tends to have a relatively small specific surface area, and a frequency distribution curve obtained by particle size distribution measurement. Tends to be sharp and has only one peak in a relatively large particle size range.
- the obtained silicon nitride powder tends to have a small ⁇ phase ratio. Even if such silicon nitride powder is sintered, it is difficult to obtain a silicon nitride sintered body having high mechanical strength and high thermal conductivity according to the present invention.
- the obtained silicon nitride powder tends to have a relatively large specific surface area, and a frequency distribution curve obtained by particle size distribution measurement. Becomes broad and has a peak top in a range where the particle diameter is relatively small, and tends to have only one peak. Further, the obtained silicon nitride powder tends to have a large ⁇ phase ratio. Even if such silicon nitride powder is sintered, it is difficult to obtain a silicon nitride sintered body having high mechanical strength and high thermal conductivity according to the present invention.
- an amorphous Si—N (—H) compound having a relatively large specific surface area and a low oxygen content is contained in a crucible, and in a temperature range of 1000 to 1400 ° C.,
- the heating rate is higher than that of the conventional case, and the heating is performed at a heating rate of 250 to 1000 ° C./hour, which is dense.
- An unprecedented silicon nitride powder according to the present invention can be obtained, which can produce a silicon nitride sintered body having both high mechanical strength and high thermal conductivity.
- the fired silicon nitride powder is preferably pulverized without being pulverized.
- the cost is reduced, and foreign substances such as metals and resins are mixed, and an excessive increase in the oxygen content is prevented.
- the inclusion of foreign matter in the final silicon nitride powder tends to be a starting point of fracture of the sintered body, which decreases the mechanical strength of the sintered body, and an excessive increase in the oxygen content may decrease the thermal conductivity.
- the crushing treatment is preferably the same treatment as the crushing of the amorphous Si—N (—H) compound, and crushing the primary particles of the silicon nitride powder. Rather, it is a process of uncoupling the relatively large aggregated particles.
- the crushing treatment it is preferable to accommodate the silicon nitride powder together with the balls in the pot and perform the vibration ball mill treatment or the jet mill treatment.
- the vibration ball mill treatment it is preferable to use a pot whose inner wall surface is lined with a resin, a ball lined with a resin, or a ball made of a silicon nitride sintered body.
- the jet mill treatment it is preferable to perform the crushing treatment with a jet mill lined with a silicon nitride sintered body.
- the atmosphere at the time of performing a crushing process is not specifically limited, Either in inert gas atmosphere, such as nitrogen, and oxygen-containing atmospheres, such as air
- the maximum value of the particle size obtained by the particle size distribution measurement of the obtained silicon nitride powder can be made 30 ⁇ m or less, so the minimum particle size obtained by the particle size distribution measurement A silicon nitride powder having a value in the range of 0.10 to 0.30 ⁇ m and a maximum particle diameter obtained by particle size distribution measurement in the range of 6 to 30 ⁇ m can be obtained.
- silicon nitride powder is used as a raw material, it becomes easy to increase the density of the molded body of silicon nitride powder.
- silicon nitride powder is uniaxially molded, by molding at a pressure of about 2 ton / cm 2 , The compact density can be greater than 48%.
- the specific surface area is 4.0 to 9.0 m 2 / g
- the proportion of ⁇ phase is less than 40%
- the oxygen content is 0.20 to 0.95 mass.
- the frequency distribution curve obtained by volume-based particle size distribution measurement by the laser diffraction scattering method has two peaks, and the peak top of the peak is in the range of 0.4 to 0.7 ⁇ m.
- Ratio of peak top frequency in the range of 5 to 3.0 (frequency of peak top in the range of particle diameter 0.4 to 0.7 ⁇ m / frequency of peak top in the range of particle diameter 1.5 to 3.0 ⁇ m ) Is 0.5 to 1.5
- the ratio D50 / D BET between the median diameter D50 ( ⁇ m) obtained by the particle size distribution measurement and the specific surface area equivalent diameter D BET ( ⁇ m) calculated from the specific surface area Silicon nitride ( ⁇ m / ⁇ m) is 3.5 or more Powder can be first obtained.
- a silicon nitride powder having the above characteristic particle size distribution can be obtained without performing pulverization or classification after firing.
- an amorphous Si—N (—H) compound having a considerably lower oxygen content than in the prior art is contained in a crucible and 250 ° C. in a temperature range of 1000 to 1400 ° C.
- This is a method for producing silicon nitride powder, which is heated and fired at an unprecedented large temperature increase rate of ⁇ 1000 ° C./hour.
- a silicon nitride powder having a granular shape and a sharp particle size distribution has been considered as a silicon nitride powder suitable for obtaining a dense and high-strength sintered body.
- the silicon nitride powder obtained by firing the amorphous Si—N (—H) compound includes the oxygen content of the amorphous Si—N (—H) compound, the temperature and environment during the firing, and The particle diameter and particle shape change depending on the temperature rising rate during crystallization with large heat generation. This is because these factors greatly influence the crystallization mechanism of silicon nitride. For example, when an amorphous Si—N (—H) compound is contained in a crucible and fired, the heat of crystallization generated along with the crystallization of silicon nitride cannot be efficiently removed. Sudden crystallization is likely to occur.
- the resulting silicon nitride powder contains a large amount of fine particles aggregated particles and columnar or acicular crystallized coarse particles, and the compact density is difficult to increase, and the sinterability Tends to be bad silicon nitride powder.
- amorphous Si—N (—H) -based compound that generates a large amount of SiO gas that promotes nucleation and has a high oxygen content as a raw material.
- SiO gas that promotes nucleation and has a high oxygen content
- a silicon nitride powder is produced by placing an amorphous Si—N (—H) compound in a crucible and firing it, amorphous Si—N (—H) having a high oxygen content It was considered necessary to calcinate using a system compound at a rate of temperature increase of 200 ° C./hour at the maximum.
- an amorphous Si—N (—H) compound with a low oxygen content can be used, or an amorphous Si— Baking an N (—H) compound at a high rate of temperature rise has not been considered appropriate as a means of obtaining silicon nitride having excellent sinterability.
- the present invention is considered to be inappropriate as a method for producing silicon nitride powder in which an amorphous Si—N (—H) compound is placed in a crucible and fired, and has an extremely low oxygen content.
- Nitriding unexpectedly combines high mechanical strength and high thermal conductivity by using an amorphous Si-N (-H) compound and adopting an extremely high temperature rise rate. It has been found that a silicon nitride powder excellent in sinterability suitable as a raw material for a silicon sintered body can be produced.
- the specific surface area, oxygen content, particle size distribution, D50 / D BET required for the silicon nitride powder of the present invention can be obtained only by crushing without pulverizing / classifying. It becomes possible to produce a silicon nitride powder having the following characteristics. Further, by only crushing the particles without crushing them, the production / acquisition cost is reduced, and foreign particles such as metal and resin are mixed into the powder and an excessive increase in the oxygen content is prevented. The inclusion of foreign matter in the silicon nitride powder tends to be a starting point of fracture of the sintered body, which decreases the mechanical strength of the sintered body, and an excessive increase in oxygen content may decrease the thermal conductivity of the sintered body.
- Each parameter of the silicon nitride sintered body manufactured using the silicon nitride powder according to the present invention and the silicon nitride powder was measured by the following method.
- composition analysis method of amorphous Si-N (-H) compound The silicon (Si) content of the amorphous Si—N (—H) compound is determined by ICP in accordance with “7 Quantitative determination of total silicon” in “JIS R1603 Chemical analysis method of fine powder of silicon nitride for fine ceramics”. Measured by luminescence analysis, nitrogen (N) content is measured by steam distillation separation neutralization titration method according to “8 Quantitative determination method of total nitrogen” in “JIS R1603 Chemical analysis method of fine powder of silicon nitride for fine ceramics” did.
- the oxygen (O) content is determined by the inert gas melting-carbon dioxide infrared absorption method (manufactured by LECO Co., Ltd.) according to “10 Quantitative determination method of oxygen” in “JIS R1603 Chemical analysis method of fine powder of silicon nitride for fine ceramics”. TC-136 type).
- ⁇ S is the true density of silicon nitride (true density of ⁇ -Si 3 N 4 is 3.186 g / cm 3 , true density of ⁇ -Si 3 N 4 is 3.192 g / cm 3 , ⁇ phase and ⁇ phase.
- the average true density was calculated by the ratio of ( 2 ) to the true density.)
- S is the specific surface area (m 2 / g).
- the oxygen content of the silicon nitride powder according to the present invention is determined by the inert gas melting-carbon dioxide infrared absorption method according to “10 Quantitative determination method of oxygen” in “JIS R1603 Chemical analysis method of fine powder of silicon nitride for fine ceramics” ( Measured by LECO, TC-136 type).
- the particle size distribution of the silicon nitride powder according to the present invention is a dispersion treatment for 6 minutes at an output of 300 W using an ultrasonic homogenizer with a sample placed in a 0.2 mass% aqueous solution of sodium hexametaphosphate and a stainless steel center cone having a diameter of 26 mm.
- the diluted solution thus prepared was measured with a laser diffraction / scattering particle size distribution measuring device (Microtrack MT3000 manufactured by Nikkiso Co., Ltd.). From the obtained frequency distribution curve and the data, the particle diameter and frequency (vol%) of the peak top of the peak, the minimum and maximum particle diameters, and the median diameter (D50) were determined.
- the proportion of the ⁇ phase of the silicon nitride powder according to the present invention is substantially composed only of ⁇ -type silicon nitride and ⁇ -type silicon nitride from the X-ray diffraction data of the silicon nitride powder obtained by X-ray diffraction measurement. (A diffraction peak other than ⁇ -type silicon nitride and ⁇ -type silicon nitride is not observed) and by Rietveld analysis, the ⁇ fraction and ⁇ fraction of silicon nitride are calculated, It was determined by dividing by the sum of the ⁇ and ⁇ fractions.
- the X-ray diffraction measurement uses a copper tube as the target and a graphite monochromator, and the X-ray detector is in the range of diffraction angle (2 ⁇ ) of 15 to 80 ° in steps of 0.02 °.
- a regular step scanning method for step scanning was adopted.
- the obtained sintered body was cut and polished to produce a 3 mm ⁇ 4 mm ⁇ 40 mm bending test piece according to JIS R1601 and a 10 mm ⁇ ⁇ 2 mm test piece for thermal conductivity measurement according to JIS R1611.
- the relative density of the sintered body was measured by the Archimedes method.
- the room temperature flexural strength (25 ° C.) is measured by a method according to JIS R1601 using an Instron universal material testing machine, and the thermal conductivity at room temperature (25 ° C.) is measured by a flash method according to JIS R1611. did.
- Example 1 The silicon nitride powder of Example 1 was prepared as follows. First, a solution of toluene having a silicon tetrachloride concentration of 30 vol% was reacted with liquid ammonia, washed with liquid ammonia, and dried to prepare silicon diimide powder. Next, the obtained silicon diimide powder was thermally decomposed using a rotary kiln furnace to obtain an amorphous Si—N (—H) compound.
- the thermal decomposition temperature of the silicon diimide powder is 1200 ° C.
- the gas introduced at the time of the thermal decomposition is an air-nitrogen mixed gas having an oxygen concentration of 0.5 vol%
- the flow rate is 72 liter / hour per 1 kg of the silicon diimide powder
- the mixture was supplied to a rotary kiln furnace and thermally decomposed.
- the obtained amorphous Si—N (—H) compound according to Example 1 had a specific surface area of 302 m 2 / g and an oxygen content of 0.16% by mass.
- the amorphous Si—N (—H) compound according to Example 1 is an amorphous Si—N (—H) compound represented by the composition formula Si 6 N 8.04 H 0.12 , that is, Si 6 N. In 2x (NH) 12-3x , x in the formula was a compound of 3.96.
- the obtained amorphous Si—N (—H) compound was crushed using a continuous vibration mill as follows.
- the obtained amorphous Si—N (—H) -based compound was placed in a pot having a resin-lined inner wall surface filled with silicon nitride sintered balls in a nitrogen atmosphere at a rate of 25 to 35 kg / hour. While maintaining, the mixture was crushed to a state where coarse aggregated particles having a particle diameter of 50 ⁇ m or more were not included.
- the particle diameter is a particle diameter of a volumetric particle size distribution measured by a laser diffraction scattering method.
- the crushed amorphous Si—N (—H) compound was crushed in a nitrogen atmosphere with a thickness of 6 mm ⁇ minor axis diameter of 8 mm ⁇ major axis diameter. It was formed into an almond shape having a thickness of 12 mm to a thickness of 8 mm, a minor axis diameter of 12 mm, and a major axis diameter of 18 mm.
- the obtained amorphous Si—N (—H) compound almond-shaped molded product was formed in a bottom surface in which square plates having a side of 270 mm and a thickness of 6 mm were provided in a grid at intervals of 40 mm.
- a box-shaped graphite container (hereinafter referred to as an A-type container) having an inner dimension of 270 mm on each side and a height of 270 mm and coated with silicon carbide on the surface (hereinafter referred to as an A-type container) at a packing density of 0.30 g / mL and about 1.
- a batch-type firing furnace (a high-temperature atmosphere furnace manufactured by Fuji Denpa Kogyo, abbreviated as a batch furnace in Table 1).
- the temperature was increased from 1000 ° C. to 1000 ° C./hour, and from 1000 ° C. to 1400 ° C. at a heating rate of 250 ° C./hour, held at 1400 ° C. for 1 hour and fired, and then cooled.
- the fired silicon nitride powder taken out of the crucible is housed in a pot with a resin-lined inner wall filled with silicon nitride sintered balls in an air atmosphere, and a batch type vibration mill is used. Then, the silicon nitride powder of Example 1 was obtained by pulverizing to a state that does not include aggregated particles having a particle diameter of 30 ⁇ m or more.
- the physical property values of the silicon nitride powder of Example 1 measured by the method described above are shown in Table 1 together with the production conditions.
- the silicon nitride powder of Example 1 has a specific surface area of 5.0 m 2 / g, an oxygen content of 0.23 mass%, a ⁇ -phase ratio of 31%, and the frequency distribution curve of the particle size distribution has two peaks. Had. Further, the peak tops are 0.63 ⁇ m and 3.00 ⁇ m, and the ratio of peak top frequencies (peak top frequency in the range of particle diameter 0.4 to 0.7 ⁇ m / particle diameter 1.5 to 3.0 ⁇ m). The frequency of peak tops in the range of 1.2) was 1.2. Moreover, the minimum value of the particle diameter obtained by the particle size distribution measurement was 0.24 ⁇ m, and the maximum value was 24 ⁇ m.
- D50 / D BET ( ⁇ m / ⁇ m) is 3.66, and there is a peak top in the particle size range of 1.5 to 3.0 ⁇ m and a peak top in the particle size range of 0.4 to 0.7 ⁇ m.
- the ratio ⁇ Dp / D50 of the particle diameter difference ⁇ Dp of each peak top to the median diameter D50 calculated by dividing the particle diameter difference ⁇ Dp by D50 was 1.72.
- the relative density was measured by the Archimedes method, the bending strength was measured at room temperature (25 ° C.), and the thermal conductivity was measured at room temperature (25 ° C.).
- the results are shown in Table 1.
- the relative density of the sintered body was 97.3%, the bending strength at room temperature was 1015 MPa, and the thermal conductivity at room temperature was 103 W / mK.
- the silicon nitride sintered material obtained using the silicon nitride powder of Example 1 was used. The body was found to be dense and have both high mechanical strength and high thermal conductivity.
- Example 2 to 12 The silicon nitride powders of Examples 2 to 12 were produced as follows.
- the same silicon diimide powder as in Example 1 was thermally decomposed using the same rotary kiln furnace as in Example 1.
- the thermal decomposition temperature of the silicon diimide powder is in the range of 600 to 1200 ° C.
- the oxygen concentration of the air-nitrogen mixed gas introduced during the thermal decomposition is in the range of 0.5 to 4 vol%
- the gas flow rate is 35 to 150 per kg of the silicon diimide powder.
- the silicon diimide powder was thermally decomposed in the same manner as in Example 1 except that the amount was adjusted in the range of liter / hour, and the specific surface area shown in Table 1 was 302 to 789 m 2 / g and the oxygen content was 0.15 to 0.50% by mass of amorphous Si—N (—H) based compounds according to Examples 2 to 12 was produced.
- x in the composition formula Si 6 N 2x (NH) 12-3x of the amorphous Si—N (—H) compounds according to Examples 2 to 12 is 3.96, 3.94 in order from Example 2. 3.94, 2.40, 2.40, 2.38, 2.38, 3.51, 3.51, 3.03, and 3.03.
- the obtained amorphous Si—N (—H) -based compound was crushed by the same method as in Example 1 and formed into an almond shape similar to that in Example 1 by the same method as in Example 1.
- the obtained amorphous Si—N (—H) compound almond-shaped moldings were filled in the following two types of graphite containers and fired in Examples 2-12.
- One is a graphite square plate having a side of 380 mm and a thickness of 8 mm provided in a lattice shape at an interval of 40.5 mm inside, each side of the bottom surface is 380 mm and the height is 380 mm.
- a box-shaped graphite container hereinafter referred to as a B-type container).
- the other is an inner diameter of 78 mm, a height of 360 mm, a thickness of 8 mm, an inner diameter of 172 mm, a height of 360 mm, and a thickness.
- a bottomed cylinder with 8 mm diameter, 266 mm inner diameter, 360 mm height and 8 mm thickness, three types of graphite cylinders provided concentrically, with a bottom diameter of 360 mm and a height of 360 mm A graphite container (hereinafter referred to as a C-shaped container).
- Amorphous Si—N (—H) compound was filled in the graphite container shown in Table 1 at a packing density in the range of 0.25 to 0.50 g / mL, and a pusher furnace manufactured by Tokai High Heat Co., Ltd. was used. Baked in a nitrogen atmosphere. When the temperature of each zone of the pusher furnace and the conveying speed of the crucible are adjusted, the temperature is raised from 1000 ° C to 1400 ° C at a speed in the range of 250 to 1000 ° C / hour, and the holding temperature (firing temperature) is 1400 ° C Thereafter, the temperature was raised to a predetermined holding temperature (described as a firing temperature in Table 1). Further, after firing at a firing temperature in the range of 1400-1700 ° C.
- the fired silicon nitride powder taken out from the crucible was pulverized as follows using a continuous vibration mill.
- the fired silicon nitride powder is supplied in an air atmosphere to a pot in which the inner wall surface filled with silicon nitride sintered balls is resin-lined while maintaining a speed in the range of 25 to 35 kg / hour, 30 ⁇ m.
- the silicon nitride powders of Examples 2 to 12 were obtained by pulverization to a state where no aggregated particles having the above particle diameter were included.
- the frequency distribution curve of the silicon nitride powder of Comparative Example 5 has only one peak, whereas the silicon nitride powder of Example 12 according to the present invention has two peaks.
- the particle size of the peak top is 0.49 ⁇ m (range of 0.4 to 0.7 ⁇ m) and 1.94 ⁇ m (range of 1.5 to 3.0 ⁇ m), and the ratio of the frequency of the peak top (particle size)
- the frequency of the peak top in the range of 0.4 to 0.7 ⁇ m / the frequency of the peak top in the range of the particle diameter of 1.5 to 3.0 ⁇ m) is 0.5 (range of 0.5 to 1.5).
- the silicon nitride powders of Examples 2 to 12 have a specific surface area of 4.0 to 8.9 m 2 / g, an oxygen content of 0.20 to 0.94 mass%, and a ⁇ -phase ratio of 5 to 35. %,
- the peak top of the frequency distribution curve of particle size distribution is 0.45 to 0.69 ⁇ m and 1.50 to 3.00 ⁇ m, and the ratio of peak top frequencies (peaks in the range of particle diameter 0.4 to 0.7 ⁇ m)
- the frequency of top / frequency of peak top in the range of 1.5 to 3.0 ⁇ m particle diameter) was 0.5 to 1.5.
- D50 / D BET ( ⁇ m / ⁇ m) is 3.74 to 5.25, the particle diameter of the peak top in the range of 1.5 to 3.0 ⁇ m, and the particle diameter of 0.4 to 0
- Example 2 In the same manner as in Example 1, 3.5 parts by weight of yttrium oxide and 2.0 parts by weight of magnesium oxide were added as sintering aids to each 94.5 parts by mass of the obtained silicon nitride powders of Examples 2-12.
- the blended powder was wet mixed in a ball mill for 12 hours using ethanol as a medium, and then dried under reduced pressure.
- a mold was formed using a uniaxial pressure press, and further CIP was formed.
- the obtained molded body was sintered in the same manner as in Example 1.
- the obtained sintered body is cut and polished, and a 3 mm ⁇ 4 mm ⁇ 40 mm bending test piece according to JIS R1601 and a 10 mm ⁇ ⁇ 2 mm test piece for measuring thermal conductivity according to JIS R1611 are obtained. Produced.
- Example 1 the relative density, the room temperature bending strength, and the thermal conductivity at room temperature were measured by the Archimedes method in the same manner as in Example 1. The results are shown in Table 1.
- the relative density of the sintered body was 96.5 to 98.8%.
- the bending strength at room temperature (25 ° C.) is 946 to 1220 MPa, and the thermal conductivity at room temperature (25 ° C.) is 100 to 122 W / mK.
- the silicon nitride obtained using the silicon nitride powders of Examples 2 to 12 It was found that the sintered body was dense as in Example 1 and had both high mechanical strength and high thermal conductivity.
- the silicon nitride powder of Comparative Example 1 was prepared as follows. The same silicon diimide powder as in Example 1 was thermally decomposed using the same rotary kiln furnace as in Example 1. The silicon diimide powder was thermally decomposed in the same manner as in Example 1 except that the flow rate of the air-nitrogen mixed gas having an oxygen concentration of 0.5 vol% introduced at the time of thermal decomposition was 38 liters / hour per kg of silicon diimide powder. As shown in Table 1, an amorphous Si—N (—H) compound having a specific surface area of 302 m 2 / g and an oxygen content of 0.13% by mass was obtained. Note that x in the composition formula Si 6 N 2x (NH) 12-3x of the amorphous Si—N (—H) compound according to Comparative Example 1 was 3.96.
- the obtained amorphous Si—N (—H) -based compound was crushed by the same method as in Example 1 and formed into an almond shape similar to that in Example 1 by the same method as in Example 1.
- the obtained amorphous Si—N (—H) -based compound almond-shaped molded product was filled in an A-type container similar to Example 1 in a similar manner at a packing density of 0.30 g / mL, and about 1.0 kg.
- Firing was performed in a nitrogen atmosphere using a high-temperature atmosphere furnace manufactured by Fuji Denpa Kogyo. After heating to 1000 ° C. at 1000 ° C./hour and 1400 ° C. at a temperature increase rate of 200 ° C./hour, holding at 1400 ° C. for 1 hour, the temperature was lowered.
- the fired silicon nitride powder taken out from the crucible was pulverized in the same manner as in Example 1 to obtain the silicon nitride powder of Comparative Example 1.
- the physical property values of the silicon nitride powder of Comparative Example 1 measured by the method described above are shown in Table 1 together with the production conditions.
- the silicon nitride powder of Comparative Example 1 has a specific surface area of 3.8 m 2 / g, an oxygen content of 0.17% by mass, a ⁇ -phase ratio of 36%, and the frequency distribution curve of the particle size distribution has one peak. Had. Further, D50 / D BET ( ⁇ m / ⁇ m) was 3.73.
- a silicon nitride sintered body was produced in the same manner as in Example 1 using the obtained silicon nitride powder of Comparative Example 1.
- the obtained silicon nitride sintered body is cut and polished, and a 3 mm ⁇ 4 mm ⁇ 40 mm bending test piece according to JIS R1601 and a 10 mm ⁇ ⁇ 2 mm test for measuring thermal conductivity according to JIS R1611 A piece was made.
- Example 1 Using the obtained test piece, the relative density was measured by the Archimedes method, the bending strength was measured at room temperature (25 ° C.), and the thermal conductivity was measured at room temperature (25 ° C.) in the same manner as in Example 1. The results are shown in Table 1. The relative density of the sintered body was 85.6%, the room temperature bending strength was 574 MPa, and the thermal conductivity at room temperature was 83 W / mK.
- Comparative Examples 2 to 4 The silicon nitride powders of Comparative Examples 2 to 4 were prepared as follows. The same silicon diimide powder as in Example 1 was thermally decomposed using the same rotary kiln furnace as in Example 1. The pyrolysis temperature is in the range of 900 to 1200 ° C., the oxygen concentration of the air-nitrogen mixed gas introduced during the pyrolysis is in the range of 1 to 4 vol%, and the gas flow rate is in the range of 50 to 250 liters / hour per kg of silicon diimide powder.
- the silicon diimide powder was thermally decomposed in the same manner as in Example 1, and the specific surface area shown in Table 1 was 306 to 480 m 2 / g and the oxygen content was 0.14 to 0.80 mass%.
- Amorphous Si—N (—H) compounds used in Comparative Examples 2 to 4 were produced. Note that x in the composition formula Si 6 N 2x (NH) 12-3x of the amorphous Si—N (—H) compounds according to Comparative Examples 2 to 4 is 3.88, 3.31 in order from Comparative Example 2. 3.96.
- the obtained amorphous Si—N (—H) compound shown in Table 1 was crushed by the same method as in Example 1, and the same almond form as in Example 1 was obtained in the same manner as in Example 1. Molded into.
- the obtained almond-shaped molded product of amorphous Si—N (—H) compound was supplied to a rotary kiln furnace manufactured by Motoyama Co., Ltd. equipped with a SiC furnace core tube and fired.
- the SiC furnace core tube of the rotary kiln furnace is provided with a heating zone with a total length of 1050 mm divided into six equal parts. During firing, the heating zone is installed from the end of the heating zone toward the fired product discharge side.
- the temperature near the outer wall of the core tube in the center of the first zone to the sixth zone is 1100 ° C.-1210 ° C.-1320 ° C .- (1420-1500 ° C.)-(1420-1500 ° C.)-(1420-1500)
- the temperature was controlled.
- a furnace core tube inclined at 0.5 to 2 ° was rotated at a rotational speed in the range of 0.5 to 2 rpm, and while flowing nitrogen gas from the inlet side at a flow rate of 8 liter / min, amorphous Si—N ( ⁇ H)
- An almond-shaped molded product of the system compound is supplied in the range of 0.5 to 3 kg / hour, and the temperature rise rate in the temperature range from 1100 ° C. to 1420 ° C.
- the physical property values of the silicon nitride powders of Comparative Examples 2 to 4 measured by the above-described method are shown in Table 1 together with the production conditions.
- the silicon nitride powders of Comparative Examples 2 to 4 have a specific surface area of 7.2 to 20.6 m 2 / g, an oxygen content of 0.20 to 1.32% by mass, and a ⁇ -phase ratio of 6 to 45%.
- the frequency distribution curve of the particle size distribution had two peaks in Comparative Examples 2 and 3, and one peak in Comparative Example 4.
- the particle sizes of the peak top of Comparative Example 2 are 0.34 ⁇ m and 13.1 ⁇ m, and the particle size of the peak top of Comparative Example 3 is 0.75 ⁇ m and 10
- the particle diameter of any peak top was different from the range of the particle diameter of the peak top of the present invention.
- the particle diameter of the peak top in Comparative Example 4 was 0.82 ⁇ m.
- the D50 / D BET ( ⁇ m / ⁇ m) was 4.85 to 10.39.
- silicon nitride sintered bodies were produced in the same manner as in Example 1.
- the obtained silicon nitride sintered body is cut and polished, and a 3 mm ⁇ 4 mm ⁇ 40 mm bending test piece according to JIS R1601 and a 10 mm ⁇ ⁇ 2 mm test for measuring thermal conductivity according to JIS R1611 A piece was made.
- Example 1 Using the obtained test piece, the relative density was measured by the Archimedes method, the bending strength was measured at room temperature, and the thermal conductivity was measured at room temperature in the same manner as in Example 1. The results are shown in Table 1.
- the relative density of the sintered body was 97.2 to 98.3%, the bending strength at room temperature was 575 to 658 MPa, and the thermal conductivity at room temperature was 123 to 133 W / mK.
- Comparative Examples 5 to 21 The silicon nitride powders of Comparative Examples 5 to 15 were prepared as follows. The same silicon diimide powder as in Example 1 was thermally decomposed using the same rotary kiln furnace as in Example 1. Except that the pyrolysis temperature is 450 to 1225 ° C, the oxygen concentration of the air-nitrogen mixed gas introduced during pyrolysis is 0 to 4 vol%, and the gas flow rate is adjusted within the range of 35 to 265 liters / kg of silicon diimide powder.
- the silicon diimide powder was thermally decomposed in the same manner as in Example 1, and Comparative Examples 5 to 21 having a specific surface area of 243 to 822 m 2 / g and an oxygen content of 0.10 to 0.85 mass% shown in Table 1 were used.
- Amorphous Si—N (—H) compounds used in 1 were prepared. Note that x in the composition formula Si 6 N 2x (NH) 12-3x of the amorphous Si—N (—H) -based compounds according to Comparative Examples 5 to 21 is 3.53, 3. 37, 2.58, 3.53, 3.37, 3.96, 3.37, 2.30, 3.98, 3.37, 3.38, 2.39, 2.40, 3.37, They were 2.40, 3.03, and 3.03.
- the obtained amorphous Si—N (—H) -based compound shown in Table 1 was crushed by the same method as in Example 1, and the same almond shape as in Example 1 was obtained in the same manner as in Example 1. Molded.
- the resulting almond-like amorphous Si—N (—H) compound molding was filled into B-type and C-type graphite containers at a packing density of 0.23 to 0.47 g / mL, and Firing was performed in a nitrogen atmosphere using a company pusher furnace.
- Adjust the temperature of each zone of the pusher furnace and the conveying speed of the crucible and increase the temperature from 1000 to 1400 ° C, when the holding temperature (firing temperature) is 1350 ° C, from 1000 to 1350 ° C, at a rate of 25 to 1200 ° C / hour. Except when the holding temperature is 1350 ° C. or 1400 ° C., the temperature is raised to a predetermined holding temperature and then calcined by holding at a temperature of 1350 to 1750 ° C. for 0.21 to 2.5 hours. did.
- the taken silicon nitride powder after firing was pulverized in the same manner as in Examples 2 to 12 to obtain silicon nitride powders of Comparative Examples 5 to 21.
- the physical properties of the silicon nitride powders of Comparative Examples 5 to 21 measured by the method described above are shown in Table 1 together with the production conditions, and the frequency distribution curve of the particle size distribution of the silicon nitride powder of Comparative Example 5 is shown in Example 12. 2 together with that of silicon nitride powder.
- the frequency distribution curve of the silicon nitride powder of Comparative Example 5 had only one peak unlike the silicon nitride powder of Example 12.
- the silicon nitride powders of Comparative Examples 5 to 21 have a specific surface area of 2.8 to 13.4 m 2 / g, an oxygen content of 0.16 to 1.30% by mass, and a ⁇ -phase ratio of 2 to 55.
- the frequency distribution curve of the particle size distribution had one peak in Comparative Examples 5 to 10, 13 and 15, and two peaks in Comparative Examples 11, 12, 14 and 16 to 21.
- the particle sizes of the peak tops of Comparative Examples 12 and 16 to 19 are 0.69 ⁇ m and 3.27 ⁇ m in order from Comparative Example 12, 0.27 ⁇ m and 2.75 ⁇ m, 0.89 ⁇ m and 3.00 ⁇ m, 0.45 ⁇ m and 1.38 ⁇ m, 0.63 ⁇ m and 3.27 ⁇ m, and the particle diameter of one peak top is different from the range of the present invention.
- the particle sizes of the peak tops of Comparative Example 14 were 1.16 ⁇ m and 6.54 ⁇ m, and the particle sizes of any of the peak tops were different from the scope of the present invention.
- the particle diameters of the peak tops of Comparative Examples 11, 20 and 21 are 0.58 ⁇ m and 1.16 ⁇ m, 0.53 ⁇ m and 2.52 ⁇ m, and 0.49 ⁇ m and 2.52 ⁇ m
- the ratio (frequency of peak top in the range of particle size 0.4 to 0.7 ⁇ m / frequency of peak top in the range of particle size 1.5 to 3.0 ⁇ m) is 3.3, 0.3 and 1.7 This was different from the scope of the present invention.
- D50 / D BET ( ⁇ m / ⁇ m) is 3.24 to 8.01, the peak top particle size in the range of 1.5 to 3.0 ⁇ m, and the particle size of 0.4 to 0.7 ⁇ m.
- the ratio ⁇ Dp / D50 of the difference between the peak tops relative to the median diameter, calculated by dividing the difference ⁇ Dp from the peak top particle diameter in the range by D50, is Comparative Example 20 having a peak top in the range. And 21 were 1.43 and 1.72.
- a silicon nitride sintered body was produced in the same manner as in Example 1 using the obtained silicon nitride powders of Comparative Examples 5 to 21.
- the obtained silicon nitride sintered body is cut and polished, and a 3 mm ⁇ 4 mm ⁇ 40 mm bending test piece according to JIS R1601 and a 10 mm ⁇ ⁇ 2 mm test for measuring thermal conductivity according to JIS R1611 A piece was made.
- the relative density was measured by the Archimedes method, the bending strength was measured at room temperature, and the thermal conductivity was measured at room temperature in the same manner as in Example 1.
- the results are shown in Table 1.
- the relative density of the sintered body was 83.0 to 95.3%, the bending strength at room temperature was 486 to 952 MPa, and the thermal conductivity at room temperature was 52 to 103 W / mK, but the bending strength at room temperature was 900 MPa or more.
- Comparative Examples 22 and 23 A commercially available grade HQ10 manufactured by SKW was used as the silicon nitride powder of Comparative Example 22, and a commercially available grade SQ manufactured by Alzchem was used as the silicon nitride powder of Comparative Example 23.
- Table 1 shows the physical property values of the silicon nitride powders of Comparative Examples 22 and 23.
- the silicon nitride powder of Comparative Example 22 has a specific surface area of 5.4 m 2 / g, an oxygen content of 0.62% by mass, and a ⁇ -phase ratio of 12% by mass.
- the particle diameter is 0.67 ⁇ m and 1.98 ⁇ m, and the ratio of the peak top frequency (the frequency of the peak top in the range of particle diameter 0.4 to 0.7 ⁇ m / the ratio of the particle diameter in the range of 1.5 to 3.0 ⁇ m The peak top frequency) was 1.5, but D50 / D BET was 3.30, which was different from the scope of the present invention.
- the silicon nitride powder of Comparative Example 23 has a specific surface area of 3.7 m 2 / g, an oxygen content of 0.51% by mass, and a peak top particle size of 0.69 ⁇ m in the frequency distribution curve of the particle size distribution.
- the difference ⁇ Dp between the particle diameter of the peak top in the range of 1.5 to 3.0 ⁇ m and the particle diameter of the peak top in the range of 0.4 to 0.7 ⁇ m is divided by D50,
- the ratio ⁇ Dp / D50 of the difference in the particle diameter of each peak top with respect to the median diameter obtained by calculating ⁇ Dp / D50 is 1.14 in Comparative Example 22 having a peak top in the range of the particle diameter. 23 was 1.04.
- a silicon nitride sintered body was produced in the same manner as in Example 1 using the obtained silicon nitride powders of Comparative Examples 22 and 23.
- the obtained silicon nitride sintered body is cut and polished, and a 3 mm ⁇ 4 mm ⁇ 40 mm bending test piece according to JIS R1601 and a 10 mm ⁇ ⁇ 2 mm test for measuring thermal conductivity according to JIS R1611 A piece was made.
- Example 1 Using the obtained test piece, the relative density was measured by the Archimedes method, the bending strength was measured at room temperature, and the thermal conductivity was measured at room temperature in the same manner as in Example 1. The results are shown in Table 1.
- the relative density of the sintered body was 88.3 and 87.2%, the bending strength at room temperature was 603 and 554 MPa, and the thermal conductivity at room temperature was 88 and 71 W / mK.
- a silicon nitride powder of Comparative Example 24 was prepared by blending three types of silicon nitride powders of A powder, B powder, and C powder in order from the larger specific surface area with different specific surface area and D50.
- the A powder includes UBE-SN-E05 manufactured by Ube Industries, Ltd. (specific surface area is 5.0 m 2 / g, oxygen content is 0.90 mass%, ⁇ -phase ratio is 1.7 mass%, D10 is 0) .471 ⁇ m, D50 is 0.736 ⁇ m, and D90 is 1.725 ⁇ m).
- B powder was prepared as follows. Nitriding having a specific surface area of 16.5 m 2 / g, an oxygen content of 2.1% by mass, and a ⁇ -phase ratio of 95% by mass with respect to 100 parts by mass of the amorphous Si—N (—H) compound of Example 5. 0.001 part by weight of silicon powder was added and mixed, and pulverized in the same manner as the amorphous Si—N (—H) compound in Example 1, and Example 1 in the same manner as in Example 1. It was molded into the same almond shape.
- the obtained amorphous Si—N (—H) compound almond-like molded product was filled in a C-type container at a packing density of 0.30 g / mL, about 3.0 kg, and a batch-type firing furnace (Fuji Radio Industry) Using a high temperature atmosphere furnace), firing was performed in a nitrogen atmosphere. Firing is performed at a heating rate of 1000 ° C./hour from 1000 ° C./hour from room temperature to 1000 ° C., held at 1150 ° C. for 0.5 hour, and then from 1150 ° C. to 1200 ° C.
- B powder (specific surface area 0.82 m 2 / g, oxygen content 0.20% by mass, ⁇ phase) The ratio was 36%, D10 was 2.664 ⁇ m, D50 was 3.947 ⁇ m, and D90 was 6.281 ⁇ m).
- C powder was prepared as follows. Nitriding having a specific surface area of 16.5 m 2 / g, an oxygen content of 2.1% by mass, and a ⁇ -phase ratio of 95% by mass with respect to 100 parts by mass of the amorphous Si—N (—H) compound of Example 5. C powder (specific surface area 0.24 m 2 / g, oxygen content 0.10 mass) by calcining and pulverizing in the same manner as B powder except that 0.0001 part by weight of silicon powder was added and mixed. %, ⁇ phase ratio 45%, D10 7.906 ⁇ m, D50 11.06 ⁇ m, D90 16.63 ⁇ m).
- the physical property values of the silicon nitride powder of Comparative Example 24 are shown in Table 1 together with the production conditions.
- the silicon nitride powder of Comparative Example 24 has a specific surface area of 2.0 m 2 / g, an oxygen content of 0.41% by mass, a ⁇ -phase ratio of 26%, and the frequency distribution curve has two peaks. The peak tops were 0.69 ⁇ m and 3.89 ⁇ m. Further, D50 / D BET ( ⁇ m / ⁇ m) was 3.37.
- a silicon nitride sintered body was produced in the same manner as in Example 1 using the obtained silicon nitride powder of Comparative Example 24.
- the obtained silicon nitride sintered body is cut and polished, and a 3 mm ⁇ 4 mm ⁇ 40 mm bending test piece according to JIS R1601 and a 10 mm ⁇ ⁇ 2 mm test for measuring thermal conductivity according to JIS R1611 A piece was made.
- Example 1 Using the obtained test piece, the relative density was measured by the Archimedes method, the bending strength was measured at room temperature, and the thermal conductivity was measured at room temperature in the same manner as in Example 1. The results are shown in Table 1.
- the relative density of the sintered body was 82.1%, the bending strength at room temperature was 496 MPa, and the thermal conductivity at room temperature was 55 W / mK.
- the silicon nitride powder obtained by the method for producing silicon nitride powder according to the present invention when used as a raw material and sintered, it has a thermal conductivity of 100 W / m ⁇ K or more at room temperature. It was also found that a silicon nitride sintered body having a bending strength of 900 MPa or more at room temperature can be obtained.
- silicon nitride powder according to the present invention it is possible to provide a silicon nitride sintered body having both high mechanical strength and high thermal conductivity and a circuit board using the same.
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Abstract
Description
本発明に係る窒化ケイ素粉末は従来技術では得られない高い機械的特性と高い熱伝導率とを合わせ持つ窒化ケイ素焼結体を得ることができる新規な窒化ケイ素粉末である。以下、この本発明に係る窒化ケイ素粉末について説明する。
非晶質窒化ケイ素の割合(質量%)=試料1g当りの分解窒素量(g)×100/39.94・・・・(1)
次に、本発明に係る窒化ケイ素焼結体及びそれを用いた回路基板について説明する。
本発明に係る窒化ケイ素粉末は、比表面積が300~800m2/g、酸素含有量が0.15~0.50質量%の非晶質Si-N(-H)系化合物を、坩堝に収容して、窒素含有不活性ガス雰囲気下又は窒素含有還元性ガス雰囲気下、1000~1400℃の温度範囲では250~1000℃/時間の昇温速度で加熱し、1400~1700℃の温度で焼成することにより好ましく製造することができる。
本発明に係る窒化ケイ素粉末を製造するために原料として用いることができる非晶質Si-N(-H)系化合物の製造方法について説明する。
Si6N2x(NH)12-3x・・・・(2)
(ただし、式中x=0.5~4であり、組成式には明記しないが、不純物として酸素やハロゲンを含有する化合物を含む。)
Si6(NH)y(NH2)24-2y・・・・(3)
(ただし、式中y=0~12であり、組成式には明記しないが、不純物としてハロゲンを含有する化合物を含む。)
本発明に係る窒化ケイ素粉末の製造方法について説明する。
非晶質Si-N(-H)系化合物のケイ素(Si)含有量は、「JIS R1603 ファインセラミックス用窒化ケイ素微粉末の化学分析方法」の「7 全けい素の定量方法」に準拠したICP発光分析により測定し、窒素(N)含有量は、「JIS R1603 ファインセラミックス用窒化ケイ素微粉末の化学分析方法」の「8全窒素の定量方法」に準拠した水蒸気蒸留分離中和滴定法により測定した。また酸素(O)含有量は、「JIS R1603 ファインセラミックス用窒化ケイ素微粉末の化学分析方法」の「10 酸素の定量方法」に準拠した不活性ガス融解-二酸化炭素赤外線吸収法(LECO社製、TC-136型)により測定した。ただし、非晶質Si-N(-H)系化合物の酸化を抑制するために、ICP発光分析または水蒸気蒸留分離中和滴定法によるケイ素・窒素含有量測定の場合は、測定のための試料前処理直前までの試料保管時の雰囲気を窒素雰囲気とし、また赤外線吸収法による酸素含有量測定の場合は、測定直前までの試料保管時及び測定時の雰囲気を窒素雰囲気とした。非晶質Si-N(-H)系化合物の水素(H)含有量は、非晶質Si-N(-H)系化合物の全量よりケイ素(Si)、窒素(N)及び酸素(O)含有量を除いた残分として、化学両論組成に基き算出して、求めた。以上より、Si、N及びHの比を求めて、非晶質Si-N(-H)系化合物の組成式を決定した。
本発明に係る窒化ケイ素粉末及び非晶質Si-N(-H)系化合物の比表面積は、Mountech社製Macsorbを用いて、窒素ガス吸着によるBET1点法にて測定した。
また、BET径DBETは、粉末を構成する全ての粒子が同一径の球と仮定して、下記の式(4)より求めた。
DBET=6/(ρS×S)・・・(4)
ここで、ρSは窒化ケイ素の真密度(α-Si3N4の真密度3.186g/cm3、β-Si3N4の真密度3.192g/cm3と、α相とβ相との比により平均真密度を算出し、真密度とした。)、Sは比表面積(m2/g)である。
本発明に係る窒化ケイ素粉末の酸素含有量は、「JIS R1603 ファインセラミックス用窒化ケイ素微粉末の化学分析方法」の「10 酸素の定量方法」に準拠した不活性ガス融解-二酸化炭素赤外線吸収法(LECO社製、TC-136型)により測定した。
本発明に係る窒化ケイ素粉末の粒度分布は、ヘキサメタリン酸ソーダ0.2質量%水溶液へ試料を入れ、直径26mmのステンレス製センターコーンを取り付けた超音波ホモジナイザーを用いて300Wの出力で6分間分散処理して調製した希薄溶液を、レーザー回折/散乱式粒子径分布測定装置(日機装株式会社製マイクロトラックMT3000)で測定した。得られた頻度分布曲線とそのデータから、ピークのピークトップの粒子径と頻度(vol%)、粒子径の最小値及び最大値、メディアン径(D50)を求めた。
窒化ケイ素粉末の粒子形態観察は、走査型電子顕微鏡(SEM)及び透過型電子顕微鏡(TEM)観察により行った。
本発明に係る窒化ケイ素粉末のβ相の割合は、X線回折測定により得られた窒化ケイ素粉末のX線回折データから、実質的にα型窒化ケイ素とβ型窒化ケイ素のみから構成されていること(α型窒化ケイ素とβ型窒化ケイ素以外の回折ピークが観察されないこと)を確認し、リートベルト解析することによって、窒化ケイ素のα分率とβ分率を算出し、β分率を、α分率とβ分率の和で除すことによって求めた。この場合のX線回折測定は、ターゲットに銅の管球を使用し、またグラファイトモノクロームメーターを使用し、回折角(2θ)15~80°の範囲を0.02°刻みでX線検出器をステップスキャンする定時ステップ走査法を採用して行った。
窒化ケイ素粉末94.5質量部に、焼結助剤として酸化イットリウム3.5質量部及び酸化マグネシウム2質量部を添加した配合粉を、媒体としてエタノールを用いて12時間ボールミルで湿式混合した後、減圧乾燥した。得られた混合物を50MPaの成形圧で62mm×62mm×厚さ7.3mmの形状及び、12.3mmφ×厚さ3.2mmの形状に金型成形した後、150MPaの成形圧でCIP成形した。得られた成形体を窒化ホウ素製坩堝に入れ、窒素ガスによる0.8MPaの加圧雰囲気下、1900℃で22時間焼結した。得られた焼結体を切削研磨加工し、JIS R1601に準拠した3mm×4mm×40mmの曲げ試験片、及びJIS R1611に準拠した熱伝導率測定用の10mmφ×2mmの試験片を作製した。焼結体の相対密度をアルキメデス法で測定した。室温曲げ強度(25℃)を、インストロン社製万能材料試験機を用いてJIS R1601に準拠した方法により、また、室温(25℃)における熱伝導率を、JIS R1611に準拠したフラッシュ法により測定した。
実施例1の窒化ケイ素粉末を次のように調製した。まず、四塩化ケイ素濃度が30vol%のトルエンの溶液を液体アンモニアと反応させ、液体アンモニアを用いて洗浄し乾燥することでシリコンジイミド粉末を作製した。次いで、得られたシリコンジイミド粉末を、ロータリーキルン炉を用いて加熱分解して非晶質Si-N(-H)系化合物を得た。シリコンジイミド粉末の熱分解温度を1200℃、熱分解時に導入するガスを酸素濃度0.5vol%の空気-窒素混合ガス、その流量をシリコンジイミド粉末1kg当たり72リットル/時間とし、シリコンジイミド粉末を、25~35kg/時間の速度を維持しながらロータリーキルン炉に供給して加熱分解した。得られた実施例1に係る非晶質Si-N(-H)系化合物は、表1に示すように、比表面積が302m2/g、酸素含有量が0.16質量%であった。また、実施例1に係る非晶質Si-N(-H)系化合物は、組成式Si6N8.04H0.12で表される非晶質Si-N(-H)系化合物、すなわちSi6N2x(NH)12-3xにおいて式中のxが3.96の化合物であった。
実施例2~12の窒化ケイ素粉末を次のように製造した。実施例1と同じシリコンジイミド粉末を実施例1と同じロータリーキルン炉を用いて加熱分解した。シリコンジイミド粉末の熱分解温度を600~1200℃の範囲、熱分解時に導入する空気-窒素混合ガスの酸素濃度を0.5~4vol%の範囲、ガスの流量をシリコンジイミド粉末1kg当たり35~150リットル/時間の範囲で調節したこと以外は実施例1と同様の方法でシリコンジイミド粉末を加熱分解し、表1に示す、比表面積が302~789m2/gで酸素含有量が0.15~0.50質量%の実施例2~12に係る非晶質Si-N(-H)系化合物を製造した。なお、実施例2~12に係る非晶質Si-N(-H)系化合物の組成式Si6N2x(NH)12-3xにおけるxは、実施例2より順に3.96、3.94、3.94、2.40、2.40、2.38、2.38、3.51、3.51、3.03、3.03であった。
比較例1の窒化ケイ素粉末を次のように調製した。実施例1と同じシリコンジイミド粉末を実施例1と同じロータリーキルン炉を用いて加熱分解した。熱分解時に導入する酸素濃度0.5vol%の空気-窒素混合ガスの流量をシリコンジイミド粉末1kg当たり38リットル/時間としたこと以外は実施例1と同様の方法でシリコンジイミド粉末を加熱分解して、表1に示す、比表面積が302m2/g、酸素含有量が0.13質量%である非晶質Si-N(-H)系化合物を得た。なお、比較例1に係る非晶質Si-N(-H)系化合物の組成式Si6N2x(NH)12-3xにおけるxは3.96であった。
比較例2~4の窒化ケイ素粉末を次のように調製した。実施例1と同じシリコンジイミド粉末を実施例1と同じロータリーキルン炉を用いて加熱分解した。熱分解温度を900~1200℃の範囲、熱分解時に導入する空気-窒素混合ガスの酸素濃度を1~4vol%の範囲、ガスの流量をシリコンジイミド粉末1kg当たり50~250リットル/時間の範囲で調節したこと以外は実施例1と同様の方法でシリコンジイミド粉末を加熱分解して、表1に示す、比表面積が306~480m2/gで酸素含有量が0.14~0.80質量%の、比較例2~4で用いる非晶質Si-N(-H)系化合物を製造した。なお、比較例2~4に係る非晶質Si-N(-H)系化合物の組成式Si6N2x(NH)12-3xにおけるxは、比較例2より順に3.88、3.31、3.96であった。
比較例5~15の窒化ケイ素粉末を次のように調製した。実施例1と同じシリコンジイミド粉末を実施例1と同じロータリーキルン炉を用いて加熱分解した。熱分解温度を450~1225℃、熱分解時に導入する空気-窒素混合ガスの酸素濃度0~4vol%、ガスの流量をシリコンジイミド粉末1kg当たり35~265リットル/時間の範囲で調節したこと以外は実施例1と同様にしてシリコンジイミド粉末を加熱分解し、表1に示す、比表面積が243~822m2/gで酸素含有量が0.10~0.85質量%の、比較例5~21で用いる非晶質Si-N(-H)系化合物を製造した。なお、比較例5~21に係る非晶質Si-N(-H)系化合物の組成式Si6N2x(NH)12-3xにおけるxは、比較例5より順に、3.53、3.37、2.58、3.53、3.37、3.96、3.37、2.30、3.98、3.37、3.38、2.39、2.40、3.37、2.40、3.03、3.03であった。
比較例22の窒化ケイ素粉末として、市販のSKW社製のグレードHQ10を、比較例23の窒化ケイ素粉末として、市販のAlzchem社製グレードSQを用いた。
比較例22及び23の窒化ケイ素粉末の物性値を表1に示す。比較例22の窒化ケイ素粉末は、比表面積が5.4m2/g、酸素含有量が0.62質量%、β相の割合が12質量%であり、粒度分布の頻度分布曲線のピークトップの粒子径が0.67μmと1.98μmであり、前記ピークトップの頻度の比(粒子径0.4~0.7μmの範囲のピークトップの頻度/粒子径1.5~3.0μmの範囲のピークトップの頻度)が1.5であったが、D50/DBETが3.30であり、本発明の範囲とは異なっていた。比較例23の窒化ケイ素粉末は、比表面積が3.7m2/g、酸素含有量が0.51質量%であり、粒度分布の頻度分布曲線のピークトップの粒子径が0.69μmと2.75μmであり、前記ピークトップの頻度の比(粒子径0.4~0.7μmの範囲のピークトップの頻度/粒子径1.5~3.0μmの範囲のピークトップの頻度)が2.8であり、D50/DBETが3.88であったが、比表面積が3.7m2/g、β相の割合が46質量%であり、本発明の範囲とは異なっていた。また、粒子径1.5~3.0μmの範囲のピークトップの粒子径と、粒子径0.4~0.7μmの範囲のピークトップの粒子径との差ΔDpをD50にて除して、ΔDp/D50を算出して求めた、メディアン径に対する各ピークトップの粒子径の差の比ΔDp/D50は、それらの粒子径の範囲にピークトップを有する比較例22が1.14で、比較例23が1.04であった。
比表面積及びD50などが異なる、比表面積が大きい方から順にA粉末、B粉末、C粉末の、3種類の窒化ケイ素粉末を配合して、比較例24の窒化ケイ素粉末を調製した。A粉末には、宇部興産株式会社製UBE-SN-E05(比表面積が5.0m2/g、酸素含有量が0.90質量%、β相の割合が1.7質量%、D10が0.471μm、D50が0.736μm、D90が1.725μm)を用いた。
Claims (10)
- 比表面積が4.0~9.0m2/gであり、β相の割合が40質量%より小さく、酸素含有量が0.20~0.95質量%であり、レーザー回折散乱法による体積基準の粒度分布測定により得られる頻度分布曲線が、二つのピークを有し、該ピークのピークトップが、0.4~0.7μmの範囲と、1.5~3.0μmの範囲にあり、前記ピークトップの頻度の比(粒子径0.4~0.7μmの範囲のピークトップの頻度/粒子径1.5~3.0μmの範囲のピークトップの頻度)が0.5~1.5であり、前記粒度分布測定により得られるメディアン径D50(μm)と前記比表面積より算出される比表面積相当径DBET(μm)との比D50/DBET(μm/μm)が3.5以上であることを特徴とする窒化ケイ素粉末。
- 粒子径1.5~3.0μmの範囲のピークトップの粒子径(μm)と粒子径0.4~0.7μmの範囲のピークトップの粒子径(μm)との差ΔDp(μm)をメジアン径D50(μm)にて除して算出される比ΔDp/D50が1.10以上であることを特徴とする請求項1記載の窒化ケイ素粉末。
- β相の割合が5~35質量%であることを特徴とする請求項1または2記載の窒化ケイ素粉末。
- 前記粒度分布測定により得られる粒子径の最小値が0.10~0.30μmの範囲にあり、前記粒度分布測定により得られる粒子径の最大値が6~30μmの範囲にあることを特徴とする請求項1~3のいずれか一項に記載の窒化ケイ素粉末。
- 請求項1~4のいずれか一項に記載の窒化ケイ素粉末を焼結して得られる窒化ケイ素焼結体。
- 前記窒化ケイ素粉末の焼結助剤として酸化マグネシウムおよび酸化イットリウムを含むことを特徴とする請求項5に記載の窒化ケイ素焼結体。
- 室温(25℃)熱伝導率が100W/m・K以上、室温(25℃)三点曲げ強度が900MPa以上であることを特徴とする請求項5または6記載の窒化ケイ素焼結体。
- 請求項5~7のいずれか一項に記載の窒化ケイ素焼結体を用いた回路基板。
- 比表面積が300~800m2/gの非晶質Si-N(-H)系化合物を、坩堝に収容して、非晶質Si-N(-H)系化合物を流動させることなく、窒素含有不活性ガス雰囲気下又は窒素含有還元性ガス雰囲気下、1400~1700℃の温度で焼成する窒化ケイ素粉末の製造方法であって、前記非晶質Si-N(-H)系化合物の酸素含有量が0.15~0.50質量%であり、前記焼成時に、前記非晶質Si-N(-H)系化合物を1000~1400℃の温度範囲では250~1000℃/時間の昇温速度で加熱することを特徴とする窒化ケイ素粉末の製造方法。
- 前記焼成で得られた窒化ケイ素粉末を、粉砕することなく、解砕して得られる窒化ケイ素粉末が、比表面積が4.0~9.0m2/gであり、β相の割合が40質量%より小さく、酸素含有量が0.20~0.95質量%であり、レーザー回折散乱法による体積基準の粒度分布測定により得られる頻度分布曲線が、二つのピークを有し、該ピークのピークトップが、0.4~0.7μmの範囲と、1.5~3.0μmの範囲にあり、前記ピークトップの頻度の比(粒子径0.4~0.7μmの範囲のピークトップの頻度/粒子径1.5~3.0μmの範囲のピークトップの頻度)が0.5~1.5であり、前記粒度分布測定により得られるメディアン径D50(μm)と前記比表面積より算出される比表面積相当径DBET(μm)との比D50/DBET(μm/μm)が3.5以上であることを特徴とする請求項9に記載の窒化ケイ素粉末の製造方法。
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Publication number | Priority date | Publication date | Assignee | Title |
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JP2019176100A (ja) * | 2018-03-29 | 2019-10-10 | Tdk株式会社 | 放熱基板 |
WO2021200865A1 (ja) * | 2020-03-30 | 2021-10-07 | デンカ株式会社 | 窒化ケイ素粉末、及び窒化ケイ素焼結体の製造方法 |
WO2021200864A1 (ja) * | 2020-03-30 | 2021-10-07 | デンカ株式会社 | 窒化ケイ素粉末、及び窒化ケイ素焼結体の製造方法 |
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KR101972234B1 (ko) * | 2017-10-25 | 2019-04-24 | 금오공과대학교 산학협력단 | 규소 스크랩을 이용한 반응소결 질화규소 소결체 제조방법 및 이로부터 제조된 반응소결 질화규소 소결체 |
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Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58199707A (ja) * | 1982-05-18 | 1983-11-21 | Ube Ind Ltd | 結晶質窒化ケイ素粉末の製法 |
JPS59207813A (ja) * | 1983-05-10 | 1984-11-26 | Ube Ind Ltd | 結晶質窒化ケイ素粉末の製法 |
JPH03177307A (ja) * | 1989-12-07 | 1991-08-01 | Denki Kagaku Kogyo Kk | 窒化ケイ素粉末 |
JPH11292522A (ja) * | 1998-04-13 | 1999-10-26 | Ube Ind Ltd | 窒化ケイ素粉末 |
JP2002265276A (ja) * | 2001-03-07 | 2002-09-18 | Hitachi Metals Ltd | 窒化ケイ素粉末および窒化ケイ素焼結体 |
JP2013071864A (ja) * | 2011-09-28 | 2013-04-22 | Denki Kagaku Kogyo Kk | 離型剤用窒化ケイ素粉末およびその製造方法 |
WO2013146713A1 (ja) * | 2012-03-28 | 2013-10-03 | 宇部興産株式会社 | 窒化ケイ素粉末の製造方法及び窒化ケイ素粉末、ならびに窒化ケイ素焼結体及びそれを用いた回路基板 |
Family Cites Families (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5759481A (en) * | 1994-10-18 | 1998-06-02 | Saint-Gobain/Norton Industrial Ceramics Corp. | Silicon nitride having a high tensile strength |
US5641438A (en) * | 1995-01-24 | 1997-06-24 | Bunyan; Michael H. | Method for forming an EMI shielding gasket |
JP3475614B2 (ja) | 1995-12-05 | 2003-12-08 | 宇部興産株式会社 | シリコンジイミド |
DE19746008A1 (de) * | 1997-10-20 | 1999-04-22 | Bayer Ag | Sinteradditive und Si02-enthaltende Siliciumnitridwerkstoffe, ein Verfahren zu deren Herstellung und deren Verwendung |
JP3669406B2 (ja) * | 1997-12-16 | 2005-07-06 | 宇部興産株式会社 | 窒化ケイ素粉末 |
JP3900695B2 (ja) | 1998-07-30 | 2007-04-04 | 宇部興産株式会社 | 窒化ケイ素粉末焼成用るつぼ |
JP3900696B2 (ja) | 1998-07-30 | 2007-04-04 | 宇部興産株式会社 | 窒化ケイ素粉末焼成用るつぼ |
JP5143988B2 (ja) * | 1999-07-22 | 2013-02-13 | オルガノジェネシス インク. | 単離された肝細胞の機能を増強させるためのイン・ビボ誘導 |
US6472075B1 (en) * | 1999-09-08 | 2002-10-29 | Ngk Spark Plug Co., Ltd. | Sintered silicon nitride member and ceramic ball |
JP2002029849A (ja) | 2000-07-14 | 2002-01-29 | Denki Kagaku Kogyo Kk | 窒化ケイ素質焼結体とその製造方法及びそれを用いた回路基板 |
JP3797905B2 (ja) | 2000-10-27 | 2006-07-19 | 株式会社東芝 | 窒化けい素セラミックス基板およびそれを用いた窒化けい素セラミックス回路基板並びにその製造方法 |
US6613443B2 (en) | 2000-10-27 | 2003-09-02 | Kabushiki Kaisha Toshiba | Silicon nitride ceramic substrate, silicon nitride ceramic circuit board using the substrate, and method of manufacturing the substrate |
JP4473463B2 (ja) * | 2001-03-26 | 2010-06-02 | 日本碍子株式会社 | 窒化珪素多孔体及びその製造方法 |
JP5268750B2 (ja) * | 2009-04-01 | 2013-08-21 | 株式会社東芝 | 耐衝撃部材およびその製造方法 |
JP5874635B2 (ja) * | 2010-08-19 | 2016-03-02 | 宇部興産株式会社 | 珪窒化物蛍光体用窒化珪素粉末並びにそれを用いたSr3Al3Si13O2N21系蛍光体、β−サイアロン蛍光体及びそれらの製造方法 |
JP5706671B2 (ja) * | 2010-11-15 | 2015-04-22 | 独立行政法人産業技術総合研究所 | 昇華再結晶法による炭化ケイ素単結晶製造用炭化ケイ素粉体及びその製造方法 |
-
2015
- 2015-06-16 TW TW104119407A patent/TW201605763A/zh unknown
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- 2015-06-16 JP JP2016529373A patent/JP6292306B2/ja active Active
- 2015-06-16 SG SG11201610089QA patent/SG11201610089QA/en unknown
- 2015-06-16 EP EP15810442.2A patent/EP3156366A4/en not_active Withdrawn
- 2015-06-16 WO PCT/JP2015/067309 patent/WO2015194552A1/ja active Application Filing
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58199707A (ja) * | 1982-05-18 | 1983-11-21 | Ube Ind Ltd | 結晶質窒化ケイ素粉末の製法 |
JPS59207813A (ja) * | 1983-05-10 | 1984-11-26 | Ube Ind Ltd | 結晶質窒化ケイ素粉末の製法 |
JPH03177307A (ja) * | 1989-12-07 | 1991-08-01 | Denki Kagaku Kogyo Kk | 窒化ケイ素粉末 |
JPH11292522A (ja) * | 1998-04-13 | 1999-10-26 | Ube Ind Ltd | 窒化ケイ素粉末 |
JP2002265276A (ja) * | 2001-03-07 | 2002-09-18 | Hitachi Metals Ltd | 窒化ケイ素粉末および窒化ケイ素焼結体 |
JP2013071864A (ja) * | 2011-09-28 | 2013-04-22 | Denki Kagaku Kogyo Kk | 離型剤用窒化ケイ素粉末およびその製造方法 |
WO2013146713A1 (ja) * | 2012-03-28 | 2013-10-03 | 宇部興産株式会社 | 窒化ケイ素粉末の製造方法及び窒化ケイ素粉末、ならびに窒化ケイ素焼結体及びそれを用いた回路基板 |
Non-Patent Citations (1)
Title |
---|
See also references of EP3156366A4 * |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2019176100A (ja) * | 2018-03-29 | 2019-10-10 | Tdk株式会社 | 放熱基板 |
JP7069967B2 (ja) | 2018-03-29 | 2022-05-18 | Tdk株式会社 | 放熱基板 |
WO2021200865A1 (ja) * | 2020-03-30 | 2021-10-07 | デンカ株式会社 | 窒化ケイ素粉末、及び窒化ケイ素焼結体の製造方法 |
WO2021200864A1 (ja) * | 2020-03-30 | 2021-10-07 | デンカ株式会社 | 窒化ケイ素粉末、及び窒化ケイ素焼結体の製造方法 |
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