×

Method of forming a truck MOS gate or a power semiconductor device

  • US 5,783,491 A
  • Filed: 02/02/1995
  • Issued: 07/21/1998
  • Est. Priority Date: 02/04/1994
  • Status: Expired due to Term
First Claim
Patent Images

1. A method of fabricating a semiconductor device, comprising the steps of:

  • (a) anisotropically etching a semiconductor substrate to form a trench extending in a direction of the thickness of said substrate;

    (b) performing a first thermal oxidation to form a first sacrificial oxide film in said trench;

    (c) removing said first sacrificial oxide film;

    (d) performing a second thermal oxidation to form a second sacrificial oxide film in said trench after said step (c);

    (e) removing said second sacrificial oxide film;

    (f) forming an insulating film comprising a part of a control electrode in said trench after said step (e); and

    (g) filling said trench to form said control electrode opposed to said substrate through said insulating film comprising said part of said control electrode.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×