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A silicon carbide sintered body exhibiting N-type semiconductivity is produced by shaping a mixture of b

A silicon carbide sintered body exhibiting N-type semiconductivity is produced by shaping a mixture of b

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A method of producing an N-type semiconductor having an electrical resistivity at 20°C. ranging from 10 ohm centimeters to 10-2 ohm centimeter and an electrical resistance that shows a positive temperature coefficient at temperatures ranging from about 800°C. to about 2000°C. and which retains N-typ

A method of producing an N-type semiconductor having an electrical resistivity at 20°C. ranging from 10 ohm centimeters to 10-2 ohm centimeter and an electrical resistance that shows a positive temperature coefficient at temperatures ranging from about 800°C. to about 2000°C. and which retains N-type semiconducting properties at temperatures ranging from about -100°C. to 2000°C. which comprises providing a substantially homogeneous mixture of a submicron powder consisting essentially of b0.3 part to 3.0 parts by weight of boron based on 100 parts by weight of said b0.1 part to 1.0 part by weight of free carbon based on 100 parts by weight of said b50°C. to 1000°C. to said free carbon and gaseous product of decomposition, shaping the mixture into a green body, and sintering the green body at a temperature ranging from about 1280°C. to 2300°C. in a sintering atmosphere which ranges from atmospheric pressure to superatmospheric pressure of 5 atmospheres and which contains nitrogen from a partial pressure of 10-1 atmosphere to a pressure of 5 atmospheres producing a sintered body having a density of at least 90% of the theoretical density for silicon carbide and having pores which are substantially non-interconnecting.