Claims
- 1. A semiconductor device obtained by forming a circuit in a surface portion of a semiconductor substrate, wherein said semiconductor substrate has an interstitial oxygen concentration (to be referred to as [Oi] hereinafter) of not more than 8E17 cm−3, an oxygen precipitate density (to be referred to as [BMD] hereinafter) of not less than 1E8 cm−3, and a resistivity of not less than 500 Ω·cm.
- 2. A device according to claim 1, wherein said circuit is formed in the surface portion of said semiconductor substrate by a device process including a heat-treating step of not more than 25 hrs as a value calculated assuming that the temperature is 1,000° C.
- 3. A device according to claim 1, wherein
said semiconductor substrate is obtained by performing heat-treating at 500 to 700° C. for not more than 5 hrs for a semiconductor substrate having an [Oi] of not more than 8E17 cm−3, and a resistivity of not less than 500 Ω·cm, thereby setting a [BMD] of not less than 1E8 cm−3, and said circuit is formed in the surface portion of said semiconductor substrate by a device process including a heat-treating step of not more than 25 hrs as a value calculated assuming that the temperature is 1,000° C.
- 4. A device according to claim 1, wherein
said semiconductor substrate has a [BMD] of not less than 1E8 cm−3, which is obtained by doping not less than 1E13 cm−3 of [N] during crystal pulling, and also has an [Oi] of not more than 8E17 cm−3 and a resistivity of not less than 500 Ω·cm, and said circuit is formed in the surface portion of said semiconductor substrate by a device process including a heat-treating step of not more than 25 hrs as a value calculated assuming that the temperature is 1,000° C.
- 5. A method of fabricating a semiconductor device by forming a circuit by using a semiconductor substrate, comprising the step of performing a heat-treating step of a device process for forming said circuit for not more than 25 hrs as a value calculated assuming that the temperature is 1,000° C., by using a semiconductor substrate having an [Oi] of not more than 8E17 cm−3, a [BMD] of not less than 1E8 cm−3, and a resistivity of not less than 500 Ω·cm.
- 6. A method according to claim 5, further comprising the step of obtaining said semiconductor substrate by performing heat-treating at 500 to 700° C. for not more than 5 hrs for a semiconductor substrate having an [Oi] of not more than 8E17 cm−3, and a resistivity of not less than 500 Ω·cm, thereby setting a [BMD] of not less than 1E8 cm−3.
- 7. A method according to claim 5, further comprising the step of obtaining said semiconductor substrate having a [BMD] of not less than 1E8 cm−3, which is obtained by doping not less than 1E13 cm−3 of [N] during crystal pulling, and also having an [Oi] of not more than 8E17 cm−3 and a resistivity of not less than 500 Ω·cm.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2000-191323 |
Jun 2000 |
JP |
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims benefit of priority under 35 USC 119 to Japanese Patent Application No. 2000-191323, filed on Jun. 26, 2000, the entire contents of which are incorporated by reference herein.