Patent · US Expired

Method of making a graded grown, high quality oxide layer for a semiconductor device

US6541394B1 · kind B1 · utility

8Cited by
7References
33Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 11, 2000
Grant dateApr 1, 2003
Priority date
Expiry dateApr 17, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/02255
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for making an oxide layer on a silicon substrate produces an oxide layer including graded portions with greatly reduced stress. The method includes growing a first oxide portion over a substrate by upwardly ramping the substrate to a first temperature lower than a SiO2 viscoelastic temperature. Thereafter a second oxide portion is grown between the first oxide portion and the silicon substrate by exposing the silicon substrate to an oxidizing ambient at a second temperature higher than the SiO2 viscoelastic temperature. The second oxide portion may have a thickness in a range of about 25 to 50% of a total thickness of the graded oxide layer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.