Patent · US Expired

Process for forming in a silicon oxide layer a portion with vertical side walls

US4800170A · kind A · utility

10Cited by
5References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 2, 1987
Grant dateJan 24, 1989
Priority date
Expiry dateOct 2, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/31111
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A process for forming a buried patterned silicon oxide layer in a silicon chip in which the layer is formed by implanting oxygen into the chip through a mask of silicon oxide on the surface of the silicon chip. The silicon oxide mask is formed to have essentially vertical side walls by interposing an irradiation step between a pair of isotropic wet etching steps in its formation.

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