Patent · US Expired

Method of forming narrow trenches in semiconductor substrates

US6977203B2 · kind B2 · utility

5Cited by
14References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 20, 2001
Grant dateDec 20, 2005
Priority date
Expiry dateNov 20, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/3086
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method of forming a trench within a semiconductor substrate. The method comprises, for example, the following: (a) providing a semiconductor substrate; (b) providing a patterned first CVD-deposited masking material layer having a first aperture over the semiconductor substrate; (c) depositing a second CVD-deposited masking material layer over the first masking material layer; (d) etching the second masking material layer until a second aperture that is narrower than the first aperture is created in the second masking material within the first aperture; and (e) etching the semiconductor substrate through the second aperture such that a trench is formed in the semiconductor substrate. In preferred embodiments, the method of the present invention is used in the formation of trench MOSFET devices.

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