Method for low temperature oxidation of silicon

• US 20030224619A1
• Filed: 06/04/2002
• Published: 12/04/2003
• Est. Priority Date: 06/04/2002
• Status: Abandoned Application

• Current Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hill, Ray, Ono, Yoshi, Burgholzer, Mark A.
• Application Number:
  US10/164,924
• Publication Number:
  US 20030224619A1
• Time in Patent Office: Days
• US Class Current: 438/771
• CPC Class Codes: C23C 8/10 Oxidising
• CPC Class Codes: C23C 8/36 using ionised gases, e.g. ionitriding
• CPC Class Codes: C30B 29/06 Silicon
• CPC Class Codes: C30B 33/005 Oxydation
• CPC Class Codes: H01L 21/02238 silicon in uncombined form, i.e. pure silicon
• CPC Class Codes: H01L 21/02255 formation by thermal treatment H01L21/02252 takes precedence; after treatment of an insulating film H01L21/3105 and subgroups
• CPC Class Codes: H01L 21/31662 of silicon in uncombined form

Abstract

A method of low-temperature oxidation of a silicon substrate includes placing a silicon wafer in a vacuum chamber; maintaining the silicon wafer at a temperature of between about room temperature and 400° C.; introducing an oxidation gas in the vacuum chamber; dissociating the oxidation gas into O(1D) radical oxygen and irradiating the surface of the silicon wafer with a xenon excimer lamp generating light at a wavelength of about 172 nm to eject electrons from the surface of the silicon wafer and forming the reactive oxidizing species over the silicon wafer; and forming an oxide layer on at least a portion of the silicon wafer.

Claims

1. A method of low-temperature oxidation of a silicon substrate comprising:

placing a silicon wafer in a vacuum chamber;

maintaining the silicon wafer at a temperature of between about room temperature and 400°

C.;

introducing an oxidation gas in the vacuum chamber;

irradiating the silicon wafer surface with a xenon excimer lamp generating light at a wavelength of about 172 nm to eject electrons from the silicon wafer surface and dissociating the oxidation gas to form a reactive oxygen species over the silicon wafer; and

forming an oxide layer on at least a portion of the silicon wafer.

2. The method of claim 1 which further includes maintaining the vacuum chamber at a pressure of between about 40 mTorr. and 90 mTorr.

3. The method of claim 1 wherein said introducing an oxidation gas in the vacuum chamber includes providing a gas flow rate of between about 2 sccm and 50 sccm.

4. The method of claim 1 wherein said introducing an oxidation gas in the vacuum chamber includes introducing N₂O into the vacuum chamber.

5. The method of claim 1 which includes, during said irradiating, applying a negative potential of between about five to ten volts to the silicon wafer.

6. The method of claim 1 which includes, after said forming, annealing the silicon wafer and oxide layer in an inert atmosphere for between about one to ten minutes at a temperature of between about 600°

C. to 750°

C.

7. A method of low-temperature oxidation of a silicon substrate comprising:

placing a silicon wafer in a vacuum chamber;

maintaining the silicon wafer at a temperature of between about room temperature and 400°

C.;

introducing an oxidation gas in the vacuum chamber;

irradiating the silicon wafer surface with a xenon excimer lamp generating light to eject electrons from the silicon wafer surface and dissociating the oxidation gas to form a reactive oxygen species over the silicon wafer; and

forming an oxide layer on at least a portion of the silicon wafer.

8. The method of claim 7 which further includes maintaining the vacuum chamber at a pressure of between about 40 mTorr. and 90 mTorr.

9. The method of claim 7 wherein said introducing an oxidation gas in the vacuum chamber includes providing a gas flow rate of between about 2 sccm and 50 sccm.

10. The method of claim 7 wherein said introducing an oxidation gas in the vacuum chamber includes introducing a gas taken from the group of oxidation gases consisting of N₂O, NO, O₂, and O₃ into the vacuum chamber.

11. The method of claim 7 wherein said generating light includes generating light at a wavelength of about 172 nm.

12. The method of claim 7 which includes, during said irradiating, applying a negative potential of between about five to ten volts to the silicon wafer.

13. The method of claim 7 which includes, after said forming, annealing the silicon wafer and oxide layer in an inert atmosphere for between about one to ten minutes at a temperature of between about 600°

C. to 750°

C.

14. A method of low-temperature oxidation of a silicon substrate comprising:

placing a silicon wafer in a vacuum chamber;

maintaining the silicon wafer at a temperature of between about room temperature and 400°

C.;

introducing N₂₀ oxidation gas in the vacuum chamber;

irradiating the silicon wafer surface with a xenon excimer lamp generating light at a wavelength of about 172 nm to eject electrons from the silicon wafer surface and dissociating the oxidation gas to form a reactive oxygen species over the silicon wafer, and applying a negative potential of between about five to ten volts to the silicon wafer;

forming an oxide layer on at least a portion of the silicon wafer; and

annealing the silicon wafer and oxide layer in an inert atmosphere for between about one to ten minutes at a temperature of between about 600°

C. to 750°

C.

15. The method of claim 14 which further includes maintaining the vacuum chamber at a pressure of between about 40 mTorr. and 90 mTorr.

16. The method of claim 14 wherein said introducing an oxidation gas in the vacuum chamber includes providing a gas flow rate of between about 2 sccm and 50 sccm.