Patent · US Expired

Fabrication of shallow trench isolation structures with rounded corner and self-aligned gate

US6709924B1 · kind B1 · utility

16Cited by
3References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 12, 2002
Grant dateMar 23, 2004
Priority date
Expiry dateNov 12, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/978
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

For fabricating a shallow trench isolation structure, a notched masking structure is formed over an active area of a semiconductor substrate. A shallow trench opening is formed at a side of the active area with a top corner of the shallow trench opening being exposed and facing a notched surface of the notched masking structure. Liner oxide is formed in a thermal oxidation process at the top corner of the shallow trench opening to round the top corner of the shallow trench opening. The liner oxide may also be formed on walls including the bottom corner of the shallow trench opening during the thermal oxidation process. The shallow trench opening is then filled with a trench dielectric material to form the shallow trench isolation structure.

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