Browse Prior Art Database

Aluminum and Aluminum Copper Etch Prevention

IP.com Disclosure Number: IPCOM000073916D
Original Publication Date: 1971-Feb-01
Included in the Prior Art Database: 2005-Feb-23
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Garland, RI: AUTHOR [+3]

Abstract

The addition of reducing agents to acid etch solutions for silicon dioxide reduces attack on exposed aluminum and aluminum-copper surfaces.

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This is the abbreviated version, containing approximately 100% of the total text.

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Aluminum and Aluminum Copper Etch Prevention

The addition of reducing agents to acid etch solutions for silicon dioxide reduces attack on exposed aluminum and aluminum-copper surfaces.

For example, a wafer whose surface was partially aluminum-copper and partially silicon dioxide was etched in a conventional 10:1 buffered hydrofluoric acid etchant and in 10:1 buffered hydrofluoric acid etchants containing various reducing agents such as alkali and ammonium hypophosphites. Different sections were etched by each etchant, the remainder being protected by wax.

The amount of attack by the etchants on the aluminum-copper surface was greatly reduced as compared to the attack on the silicon dioxide layer when the etchants containing the reducing agents were used.

Similar results were obtained when the Al-Cu Lands were covered with sputtered SiO(2) which was subsequently etched for making contact to the underlying metal.

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