Method of cleaning a surface of a semiconductor substrate by a heat treatment in an inert gas atmosphere

• US 5,849,102 A
• Filed: 02/28/1997
• Issued: 12/15/1998
• Est. Priority Date: 02/28/1996
• Status: Expired due to Term

• Current Assignee: Longitude Semiconductor S.à r.l. (Vector Capital Corporation)
• Original Assignee: NEC Corporation
• Inventors: Okonogi, Kensuke
• Primary Examiner(s): Warden, Robert
• Assistant Examiner(s): CARRILLO, BIBI SHARIDAN
• Application Number:
  US08/808,169
• Time in Patent Office: 655 Days
• Field of Search: 134/2, 134/3, 134/19, 134/21, 134/902, 438/906, 438/770
• US Class Current: 134/19
• CPC Class Codes: H01L 21/02046 Dry cleaning only H01L21/02085 takes precedence
• CPC Class Codes: H01L 21/6704 for wet cleaning or washing
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/67098 Apparatus for thermal treatment
• CPC Class Codes: Y10S 134/902 Semiconductor wafer
• CPC Class Codes: Y10S 438/906 Cleaning of wafer as interim step

Abstract

A method of cleaning a surface of a semiconductor comprising the steps of a) washing the semiconductor surface with chemicals to remove particles and metal impurities from the surface; b) inserting the semiconductor into a furnace that contains a gas mixture of nitrogen gas and a second inert gas; c) replacing the gas mixture with a third inert gas; d) heating the furnace containing the third inert gas for a predetermined period of time; and e) replacing the third inert gas in the furnace with oxygen and thermally oxidizing the surface of the semiconductor to form an oxide film on the surface.

Claims

1. A method of cleaning and oxidizing a surface of a silicon-on-insulator semiconductor comprising the steps of:

washing the semiconductor surface with chemicals to remove particles and metal impurities from the surface;

inserting the semiconductor into a furnace that has an atmosphere of a first gas to prevent formation of an oxide film on the surface;

replacing the first gas mixture of the furnace with argon;

removing particles and metal impurities from the surface that were not removed by the washing step by heating the furnace containing said argon to a first temperature for a first period of time;

replacing said argon contained in the furnace with an oxygen gas; and

thermally oxidizing the surface in the furnace to form an oxide film on the surface.

2. The method of claim 1, wherein said second inert gas of said first gas mixture is argon.

3. The method of claim 1, further comprising the step of maintaining the first temperature during the step of replacing said argon with said oxygen gas.

4. The method of claim 2, wherein the first temperature is from 800°

C. to 900°

C. and the first period of time is 20 minutes.