Patent · US Expired

Process for forming shallow trench isolation

US5747377A · kind A · utility

65Cited by
4References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 6, 1996
Grant dateMay 5, 1998
Priority date
Expiry dateSep 6, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/947
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A process for forming a shallow trench isolation is disclosed. Initially, a gate oxide layer is formed on a substrate, and a silicon nitride, which defines an active area, is then patterned on the gate oxide layer. Next, hemispherical grain silicon is formed on the silicon nitride, the sidewalls of the silicon nitride, and the exposed gate oxide layer. Portions of the gate oxide layer are removed to form oxide islands using the silicon nitride and the hemispherical grain silicon as mask. Thereafter, portions of the substrate are removed using the oxide islands as mask. Finally, the exposed substrate is thermally oxidized to form the field oxide structure of the present invention.

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