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. 15, 2015
Filed:
Feb. 04, 2014
Globalfoundries Inc., Grand Cayman, KY;
Tanya Andreeva Atanasova, Dresden, DE;
Reiner Willeke, Dresden, DE;
Anh Ngoc Duong, Fremont, CA (US);
GLOBALFOUNDRIES INC., Grand Cayman, KY;
Abstract
Methods for wet etching a UBM layer and the resulting devices are disclosed. Embodiments may include patterning metal bumps on a wafer that has at least two metal layers thereon; exposing the wafer to a first acid solution to remove a portion of a first of the two metal layers exposed by the patterning of the metal bumps; and exposing the wafer to a second acid solution to remove a portion a second of the two metal layers exposed by the patterning of the metal bumps and the exposure of the wafer to the first acid solution, wherein an undercut below the metal bumps, formed by removal of the portions of the first and second metal layers, is less than 1.5 microns.