Claims
- 1. A semiconductor device in which at least one semiconductor element is disposed on an electro-insulative silicon carbide sintered body of an electrical resistivity of 10.sup.7 .OMEGA.-cm or more at 25.degree. C. and of a linear thermal expansion coefficient of not larger than 4.0.times.10.sup.-6, said sintered body having a relative density of not less than 90%.
- 2. A semiconductor device comprising at least one semiconductor element disposed through a metallic film on an electro-insulative silicon carbide sintered body and a metallic substrate carrying the sintered body; the silicon carbide sintered body containing at least 90% by weight of silicon carbide and less than 3.5% by weight of beryllium, having an electrical resistivity of 10.sup.3 ohm.multidot.cm or more, a thermal conductivity of 0.5 to 0.75 cal/cm.multidot.sec.multidot..degree.C. and a relative density of 96 to 100%.
- 3. A semiconductor device which comprises at least one semiconductor element disposed through a metallic film on an electro-insulative silicon carbide body containing BeO in an amount of 0.1 to 3.5% by weight of Be.
- 4. A semiconductor device according to claim 1 or claim 3, wherein the sintered body consisting essentially of 0.1 to 3.5 wt.% of beryllium, up to 0.1 wt.% of aluminum, up to 0.1 wt.% of boron, up to 0.4 wt.% of free carbon the balance being silicon carbide; said sintered body having density of at least 90% relative density with respect to the theoretical density of said silicon carbide and thermal conductivity of at least 0.4 cal/cm.multidot.sec.multidot..degree.C. at 25.degree. C., electrical resistivity of at least 10.sup.7 ohm.multidot.cm at 25.degree. C. and coefficient of thermal expansion of up to 4.times.10.sup.-6 /.degree.C. from 25.degree. C. to 300.degree. C.
- 5. A semiconductor device according to any one of claims 1 to 3, wherein alpha-type silicon carbide is the principal component of said silicon carbide.
- 6. A semiconductor device according to claim 1 or claim 3, wherein the sintered body has an electrical resistivity of 10.sup.13 ohm.multidot.cm or more, a thermal conductivity of 0.5-0.75 cal/cm.multidot.sec.multidot..degree.C., and a relative density of 96-100%.
- 7. A semiconductor device according to claim 1 or claim 3, wherein the sintered body has a relative density of 90% or more, said sintered body consisting essentially of 0.1 to 3.5% by weight of beryllium in the form of beryllium oxide and a balance of silicon carbide, said sintered body being produced by sintering a mixture consisting essentially of beryllium oxide and a balance substantially of silicon carbide having an average grain size of up to 10 .mu.m in a non-oxidizing atmosphere at 1850.degree. to 2500.degree. C.
- 8. A semiconductor device according to claim 1, wherein the silicon carbide sintered body contains at least 90% by weight of silicon carbide and less than 3.5% by weight of beryllium, and has an electrical resistivity of 10.sup.13 ohm.multidot.cm or more, a thermal conductivity of 0.5 to 0.75 cal/cm.multidot.sec.multidot..degree.C. and a relative density of 96 to 100%.
- 9. A semiconductor device according to claim 1, wherein the silicon carbide sintered body consists essentially of silicon carbide and beryllium in an amount sufficient to render the sintered body electro-insulative and to give the body a thermal conductivity of at least 0.4 cal/cm.multidot.sec.multidot..degree.C.
- 10. A semiconductor device according to claim 2, wherein the sintered body consists essentially of 0.3 to 3.5 wt. % of beryllium, up to 0.1 wt. % of aluminum, up to 0.1 wt. % of boron, up to 0.4 wt. % of free carbon, the balance being silicon carbide; said sintered body having a coefficient of thermal expansion of up to 4.times.10.sup.-6 /.degree.C. from 25.degree. C. to 300.degree. C.
- 11. A semiconductor device according to claim 2, wherein the sintered body consists essentially of 0.1 to 3.5% by weight of beryllium in the form of beryllium oxide and a balance of silicon carbide, said sintered body being produced by sintering a mixture consisting essentially of beryllium oxide and a balance substantially of silicon carbide having an average grain size of up to 10 .mu.m in a non-oxidizing atmosphere at 1850.degree. to 2500.degree. C.
Priority Claims (3)
Number |
Date |
Country |
Kind |
54-142059 |
Nov 1979 |
JPX |
|
55-75601 |
Jun 1980 |
JPX |
|
8010679.9 |
Nov 1980 |
EPX |
|
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part application Ser. No. 203,554, filed Nov. 5, 1980, titled "ELECTRICALLY INSULATING SUBSTRATE AND A METHOD OF MAKING SUCH A SUBSTRATE", now U.S. Pat. No. 4,370,421.
US Referenced Citations (4)
Foreign Referenced Citations (1)
Number |
Date |
Country |
56-15047 |
Feb 1981 |
JPX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
203554 |
Nov 1980 |
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