Browse Prior Art Database

Selective Etching of Glass

IP.com Disclosure Number: IPCOM000092948D
Original Publication Date: 1967-Apr-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Gajda, JJ: AUTHOR

Abstract

This differential etch permits selectivity of attack to completely etch away the protective glass coating on semiconductor chips. Such is effected without damaging the underlying aluminum or aluminum-silicon interconnections.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Selective Etching of Glass

This differential etch permits selectivity of attack to completely etch away the protective glass coating on semiconductor chips. Such is effected without damaging the underlying aluminum or aluminum-silicon interconnections.

The etch has application in transistor manufacturing, where 2-3 mil openings in the glass have to be made in order to contact the metal interconnections. This etch has the advantage of attacking the glass while not damaging the underlying metal such as aluminum or aluminum-silicon interconnection stripes.

The composition of two solutions is as follows: Solution 1 Solution 2

2 parts HF (48%) 2 parts HF (48%)

1 part HNO(3) (70%) 1 part HNO(3) (70%)

3 parts Glycerine 12 parts Glycerine.

1