Patent · US Expired

Method of anisotropically etching monocrystalline, disk-shaped wafers

US5282926A · kind A · utility

8Cited by

8References

3Claims

0Family size

Assignee

Robert Bosch GmbH · DE

Inventors

Hans-Peter Trah · Reutlingen, DE
Guenther Findler · Stuttgart, DE

Key dates

Filing date	Aug 22, 1991
Grant date	Feb 1, 1994
Priority date	—
Expiry date	Aug 22, 2011

Classification

Technology area (CPC G)Physics
CPC primaryG03F1/22
WIPO fieldOptics
WIPO sectorInstruments

Abstract

A method for anisotropically etching recesses in a monocrystalline disk-shaped wafer is proposed, by which structural elements such as membranes or through openings can be made in the wafer. To this end, a mask layer is applied to a first surface of the wafer and subsequently structured by making at least one opening in the mask layer. The dimensioning of the at least one opening, and its orientation with respect to the crystal orientation of the wafer and to the anisotropic properties of the wafer material, are selected such that the desired size and shape of the area of the recess or outlet hole are attained by anisotropic etching into the wafer through the at least one opening in the mask layer and by purposeful underetching of the mask layer.

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