Patent · US Expired

Method and apparatus for sequentially etching a wafer using anisotropic and isotropic etching

US6221784A · kind A · utility

14Cited by

10References

24Claims

0Family size

Assignee

Applied Materials, Inc. · US

Inventors

Ursula Ingeborg Schmidt · Dresden, DE
Walter Schoenleber · Holzgerlingen, DE
Michael J. Schmidt · Queen Creek, US

Key dates

Filing date	Nov 29, 1999
Grant date	Apr 24, 2001
Priority date	—
Expiry date	Nov 29, 2019

Classification

Technology area (CPC H)Electricity
CPC primaryH01L21/31116
WIPO fieldSemiconductors
WIPO sectorElectrical engineering

Abstract

An apparatus and method for in-situ etching of a substrate comprising both a polysilicon layer and an overlying dielectric layer. An embodiment of the method comprises an anisotropic etch of the dielectric layer in a chamber using a first fluorinated gas (such as CF.sub.4, NF.sub.3, SF.sub.6, and the like) as an etch gas to expose at least a portion of underlying polysilicon layer. Following the anisotropic etch and without removing the substrate from the chamber, i.e., in situ, an isotropic etch is preformed on the underlying polysilicon layer using a second fluorinated gas (such as CF.sub.4, NF.sub.3, SF.sub.6, and the like) as an etch gas.

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