×

Method for creating thick oxide on the bottom surface of a trench structure in silicon

  • US 6,861,296 B2
  • Filed: 06/19/2002
  • Issued: 03/01/2005
  • Est. Priority Date: 08/16/2000
  • Status: Expired due to Term
First Claim
Patent Images

1. A method of forming a gate dielectric layer of a trenched gate field effect transistor having source regions proximate the trenched gate, the method comprising the steps of:

  • forming a trench extending into a silicon region;

    forming a first layer of a dielectric material extending at least along sidewalls and bottom of the trench; and

    forming a second layer of dielectric material at the bottom of the trench such that a thickness of the first layer of a dielectric material smoothly changes from a substantially uniform thickness along the sidewalls of the trench to a thickness of the combined first and second layers of dielectric material along the bottom of the trench without a reduction in thickness in the transition region from the trench sidewalls to the trench bottom.

View all claims
  • 6 Assignments
Timeline View
Assignment View
    ×
    ×