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:
Dec. 31, 2013
Filed:
Aug. 21, 2007
Applicant:
Ashay Chitnis, Goleta, CA (US);
Inventor:
Ashay Chitnis, Goleta, CA (US);
Assignee:
Cree, Inc., Durham, NC (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 21/302 (2006.01); H01L 21/461 (2006.01);
U.S. Cl.
CPC ...
Abstract
The present invention is directed to post-deposition, wet etch processes for patterning AuSn solder material and devices fabricated using such processes. The processes can be applied to uniform AuSn layers to generate submicron patterning of thin AuSn layers having a wide variety of features. The use of multiple etching steps that alternate between different mixes of chemicals enables the etch to proceed effectively, and the same or similar processes can be used to etch under bump metallization. The processes are simple, cost-effective, do not contaminate equipment or tools, and are compatible with standard cleanroom fabrication processes.