Method of surface preparation

• US 6,465,374 B1
• Filed: 01/13/2000
• Issued: 10/15/2002
• Est. Priority Date: 10/21/1997
• Status: Expired due to Fees

• Current Assignee: FSI International, Inc. (Tokyo Electron Limited)
• Original Assignee: FSI International, Inc. (Tokyo Electron Limited)
• Inventors: Butterbaugh, Jeffery W., Schwab, Brent
• Primary Examiner(s): DANG, THI D
• Application Number:
  US09/482,222
• Time in Patent Office: 1,006 Days
• Field of Search: 438/795, 438/796, 438/906
• US Class Current: 438/795
• CPC Class Codes: C23C 16/481 by radiant heating of the substrate
• CPC Class Codes: H01L 21/02046 Dry cleaning only H01L21/02085 takes precedence
• CPC Class Codes: H01L 21/67115 mainly by radiation
• CPC Class Codes: Y10S 438/906 Cleaning of wafer as interim step
• CPC Class Codes: Y10S 977/841 Environmental containment or disposal of nanostructure material

Abstract

A semiconductor substrate is heated via exposure to ultraviolet radiation substantially in the absence of a halogen containing chemical and subsequently exposed to a halogen-containing gas in the absence of ultraviolet radiation to remove contaminants therefrom.

Claims

1. A method of treating a semiconductor substrate comprising the steps of:

providing a semiconductor substrate having oxides on the surface thereof in a process chamber;

applying ultraviolet radiation to the substrate substantially in the absence of a halogen containing chemical to heat the substrate;

exposing the heated substrate, in the absence of ultraviolet radiation to a halogen-containing gas; and

preparing the substrate prior to heating the substrate to remove at least some of the oxide on the surface of the substrate.

2. The method of claim 1 wherein substantially all of the oxide is removed during the preparation of the substrate.

3. The method of claim 1 wherein the during the preparation of the substrate, the substrate is exposed to gaseous anhydrous HF and gaseous IPA.

11. The method of claim 2 further comprising the step of oxidizing the semiconductor substrate following the exposing step.

4. A method of treating a semiconductor substrate comprising the steps of:

providing a semiconductor substrate in a process chamber;

applying ultraviolet radiation to the substrate substantially in the absence of a halogen containing chemical to heat the substrate;

exposing the heated substrate, in the absence of ultraviolet radiation to a halogen-containing gas; and

depositing silicon on the substrate.

5. The method of claim 4 further comprising the step of oxidizing the semiconductor substrate following the exposing step.

6. The method of claim 5 wherein the semiconductor is exposed to ultraviolet radiation during the oxidizing step.

7. The method of claim 6 wherein the ultraviolet radiation is applied at a heating level during the oxidizing step.

8. A method of treating a gallium arsenide semiconductor substrate comprising the steps of:

providing a gallium arsenide semiconductor substrate in a process chamber;

applying ultraviolet radiation to the substrate substantially in the absence of a halogen containing chemical to heat the substrate; and

exposing the heated substrate, in the absence of ultraviolet radiation to a halogen-containing gas.

9. A method of treating a semiconductor substrate comprising the steps of:

providing a semiconductor substrate in a process chamber;

applying ultraviolet radiation to the substrate substantially in the absence of a halogen containing chemical to heat the substrate; and

exposing the heated substrate, in the absence of ultraviolet radiation to a halogen-containing gas wherein the halogen-containing gas contains chlorine.

10. The method of claim 9 wherein the halogen-containing gas is Cl₂.

12. The method of claim 10 wherein during the applying step, the substrate is heated to a temperature of at least about 80°

C.

13. The method of claim 10 wherein during the applying step, the substrate is heated to a temperature of at least about 100°

C.

14. The method of claim 10 wherein during the applying step, the substrate is heated to a temperature of at least 60°

C. above the temperature of the substrate prior to the applying step.

15. A method of treating a semiconductor substrate comprising the steps of:

providing a semiconductor substrate including oxides on the surface thereof in a process chamber;

removing at least some of the oxide on the surface of the substrate;

applying ultraviolet radiation to the substrate substantially in the absence of a halogen containing chemical to heat the substrate;

exposing the heated substrate, in the absence of ultraviolet radiation to a halogen-containing gas; and

oxidizing the semiconductor substrate following the exposing step.

16. The method of claim 15 wherein the substrate comprises silicon and the halogen-containing gas comprises chlorine.

17. The method of claim 15 wherein the ultraviolet radiation is applied to the substrate to heat the substrate in the absence of a halogen-containing gas.

18. The method of claim 15 wherein prior to the removing step, the substrate is heated to a predetermined temperature via exposure to ultraviolet radiation and the substrate is exposed to a halogen-containing gas.

19. The method of claim 15 wherein the process chamber is substantially evacuated following the removing step and before applying the ultraviolet radiation to heat the substrate.

20. A method of treating a substrate comprising the steps of:

providing a substrate including oxides on the surface thereof in a process chamber;

preparing the substrate to remove at least some of the oxide from the substrate;

applying ultraviolet radiation to the substrate to heat the substrate; and

exposing the heated substrate, in the absence of ultraviolet radiation to a halogen-containing gas.

21. The method of claim 20 wherein the exposing step is followed by a post-teatment process in which the surface of the substrate is at least partially oxidized.