Silicon nitride powder production method, silicon nitride powder, silicon nitride sintered body and circuit substrate using same
AssigneeUbe Industries, Ltd.
InventorsKoji Shibata, Takuji Ohmaru, Takeshi Yamao, Masataka Fujinaga, Michio Honda, Takayuki Fujii
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Abstract
A method of producing a silicon nitride powder includes heating an amorphous Si—N(—H)-based compound in which assuming that the specific surface area is RS (m2/g) and the oxygen content ratio is RO (mass %), RS/RO is 500 or more, at a temperature rising rate of 12 to 100° C./min in a temperature range from 1,000 to 1,400° C. while flowing the compound by a continuous firing furnace.
Claims20
A method of producing a silicon nitride powder comprising firing an amorphous Si—N(—H)-based compound having a specific surface area of 400 to 1,200 m2/g at a temperature of 1,400 to 1,700° C. in a nitrogen-containing inert gas atmosphere or a nitrogen-containing reducing gas atmosphere while flowing the compound in a continuous firing furnace, wherein:
- assuming that a specific surface area of said amorphous Si—N(—H)-based compound is RS (m2/g) and an oxygen content ratio is RO (mass %), RS/RO is 500 or more, and
- during said firing, said amorphous Si—N(—H)-based compound is heated at a temperature rising rate of 12 to 100° C/min in a temperature range from 1,000 to 1,400° C.
A silicon nitride powder having a specific surface area from 5 to 30 m2/g;
- wherein, assuming that the content ratio of oxygen existing in a region from a particle surface to 3 nm beneath the particle surface is FSO (mass%), the content ratio of oxygen existing in a more inward side than 3 nm beneath the particle surface is FIO (mass %), and a specific surface area is FS (m2/g), FS/FSO is from 8 to 25 and FS/FIO is 22 or more;
- and when a particle size distribution on a volume basis is measured by a laser diffraction particle size distribution meter, the ratio D10/D90 between a 10 vol % diameter D10 and a 90 vol % diameter D90 is 0.1 or more.
Dependencies are inferred from the claim text.