Patent · US Active

Polysilicon etch with high selectivity

US8916477B2 · kind B2 · utility

13Cited by
1References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 2013
Grant dateDec 23, 2014
Priority date
Expiry dateJun 12, 2033

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P80/30
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Provided are methods and systems for removing polysilicon on a wafer. A wafer can include a polysilicon layer and an exposed nitride and/or oxide structure. An etchant with a hydrogen-based species, such as hydrogen gas, and a fluorine-based species, such as nitrogen trifluoride, can be introduced. The hydrogen-based species and the fluorine-based species can be activated with a remote plasma source. The layer of polysilicon on the wafer can be removed at a selectivity over the exposed nitride and/or oxide structure that is greater than about 500:1.

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