Claims
- 1. A method of manufacturing a semiconductor substrate having a support substrate formed of boron-doped high-concentration P-type monocrystal silicon, an oxide film formed on the support substrate, and a thin film of monocrystal silicon formed on the oxide film, comprising:
- doping boron into the support base so that a resistivity of the support base is 0.1 .OMEGA..cm or less;
- heat treating a silicon substrate on which the thin film of monocrystal silicon is formed at 1100.degree. C. or higher for 30 min or longer within a reducing atmosphere;
- attaching the heat treated silicon substrate to the high-concentration P-type support substrate via the oxide film formed on a surface of any one of the support substrate and the P-type silicon substrate and heat treating the attached substrates at 950.degree. C. or higher for 10 min or longer to bond the attached substrates together; and
- thinning the bonded silicon substrate,
- wherein said reducing atmosphere comprises at least one member selected from the group consisting of H.sub.2, CO, CO.sub.2, Ar, He, Ne, Kr and Xe.
- 2. The method of manufacturing a semiconductor substrate of claim 1, which further comprises the step of forming the oxide film with a thickness from 10 nm or more to 5 .mu.m or less on the support substrate or the silicon substrate.
- 3. The method of manufacturing a semiconductor substrate of claim 1, wherein said heat treating of the silicon substrate is carried out so that the thin film has an oxygen concentration of 5.times.10.sup.17 cm.sup.-3 or less.
- 4. The method of claim 1, wherein said oxide film has a thickness of 50 nm to 1 .mu.m.
- 5. The method of claim 1, wherein said reducing atmosphere comprises H.sub.2.
- 6. The method of claim 1, wherein said heat treating of the attached substrates is carried out in an atmosphere comprising N.sub.2.
- 7. The method of claim 1, wherein said silicon thin film has a thickness of 10 nm-10 .mu.m.
- 8. The method of claim 1, wherein said thin film has a resistivity of 0.1-100 .OMEGA.cm.
- 9. A method for manufacturing a semiconductor substrate, comprising:
- heat treating a silicon substrate at 1100.degree. C. or higher for 30 minutes or longer in a reducing atmosphere;
- attaching said heat treated silicon substrate to a boron doped silicon support base having a resistivity of 0.1 .OMEGA.cm or less, via an oxide film on a surface of said support base or said silicon substrate, and heat treating the attached support silicon substrate at 950.degree. C. or higher for ten minutes or longer; and
- thinning the attached silicon substrate,
- wherein said reducing atmosphere comprises at least one member selected from the group consisting of H.sub.2, CO, CO.sub.2, Ar, He, Ne, Kr and Xe.
- 10. The method of claim 9, further comprising the step of forming said oxide film having a thickness of 50 nm to 1 .mu.m on said support base or said silicon substrate.
- 11. The method of claim 9, wherein said thinned attached silicon substrate has an oxygen concentration of 5.times.10.sup.17 cm.sup.-3 or less.
- 12. The method of claim 9, wherein said oxide film has a thickness of 50 nm to 1 .mu.m.
- 13. The method of claim 9, wherein said reducing atmosphere comprises H.sub.2.
- 14. The method of claim 9, wherein said heat treating of said attached support and silicon substrate is carried out in an atmosphere comprising N.sub.2.
- 15. The method of claim 9, wherein said thinning is carried out until the attached silicon substrate has a thickness of 10 nm to 10 .mu.m.
- 16. The method of claim 9, wherein said thinned attached silicon substrate has a resistivity of 0.1-100 .OMEGA.cm.
- 17. The method of claim 9, wherein said semiconductor substrate produced by said method comprises a support base of boron-doped monocrystalline silicon, an oxide film on said support base, and a film of monocrystalline silicon on said oxide film.
Priority Claims (1)
Number |
Date |
Country |
Kind |
6-169588 |
Jul 1994 |
JPX |
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Parent Case Info
This is a Division of application Ser. No. 08/486,245 filed on Jun. 7, 1995, now pending.
US Referenced Citations (6)
Divisions (1)
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Number |
Date |
Country |
Parent |
486245 |
Jun 1995 |
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