Browse Prior Art Database

Chemical Etching of Aluminum

IP.com Disclosure Number: IPCOM000092828D
Original Publication Date: 1967-Mar-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Palmer, MD: AUTHOR

Abstract

This method improves aluminum subtractive etching through the elimination of hydrogen gas.

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

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Chemical Etching of Aluminum

This method improves aluminum subtractive etching through the elimination of hydrogen gas.

Etching of aluminum creates hydrogen gas in small bubbles which act as a barrier to the etchant, typically HNO(3) or H(3)PO(4). The bubbles prevent aluminum etching resulting in shorts. These occur where the circuit patterns are very dense or a large number of wafers are required to be etched at a single etching operation.

The reduction of the vapor pressure over the etching solution by approximately 1 atmosphere reduces the hydrogen bubbles. Typically, 750 mm mercury vacuum removes the hydrogen gas as it is formed. The low vapor pressure permits the hydrogen to escape from the etchant as it is formed. The process reduces the failure rate of integrated components from approximately 30% to nearly 0% for the aluminum etching operation.

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