Method of wet etching vias and articles formed thereby

Details Method of wet etching vias and articles formed thereby Method of wet etching vias and articles formed thereby

2006-09-05

2006-09-05

Potter, Roy (Department: 2822)

Semiconductor device manufacturing: process

Coating with electrically or thermally conductive material

To form ohmic contact to semiconductive material

C438S667000

Reexamination Certificate

active

07101789

ABSTRACT:
A method for forming smooth walled, prismatically-profiled through-wafer vias and articles formed through the method. An etch stop material is provided on a wafer, which may be a <110> silicon wafer. A mask material is provided on the etch stop material and patterned in such a way as to lead to the formation of vias that have at least one pair of opposing side walls that run parallel to a <111> plane in the wafer. A wet etchant, such as potassium hydroxide, is used to etch vias in the wafer. The use of a wet etchant leads to the formation of smooth side walls. This method allows an aspect ratio of height versus width of the vias of greater than 75 to 1.

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