The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 14, 2009
Filed:
May. 26, 2006
David Paul Jones, South Glamorgan, GB;
Hugo R. G. Burke, Wales, GB;
David Paul Jones, South Glamorgan, GB;
Hugo R. G. Burke, Wales, GB;
International Rectifier Corporation, El Segundo, CA (US);
Abstract
A process for etching a thick aluminum contact layer of a semiconductor wafer comprises the formation of a wet etch photoresist mask and the opening of a window in the mask, followed by a wet etch of a first portion of the thickness of the contact layer exposed by the window and the inherent under cutting of the contact layer under the mask window. A dry etch is next carried out, using the same window as a mask, to cut the remaining web of the contact layer under the window. An etch stop layer of Ti or TiN can be formed within the body of the contact layer to define the depth of the initial wet etch into the contact layer.