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:
Nov. 03, 2015
Filed:
May. 13, 2014
National Center for Advanced Packaging Co., Ltd., Wuxi, Jiangsu, CN;
Wenqi Zhang, Jiangsu, CN;
NATIONAL CENTER FOR ADVANCED PACKAGING CO., LTD., Wuxi, Jiangsu, CN;
Abstract
Techniques for fabricating fine-pitch micro-bumps are disclosed. According to one embodiment, a fabrication process may comprise the following steps: depositing a dielectric layer on a wafer; forming a pattern of through holes in the dielectric layer; depositing a seed metal layer on top of the dielectric layer and inside the through holes; depositing a layer of UBM metal on top of the seed metal layer (including inside the holes), and further filling the holes with a low melting point metal; performing chemical mechanical polishing (CMP) to remove conductive material(s) outside the holes and/or on the surface of the dielectric layer, such that the metal stacks of adjacent holes are insulated by the dielectric material between them; and etching the dielectric material surrounding the holes to cause the tip of the metal stacks to extend slightly higher than the surrounding dielectric surface, thereby forming fine-pitch micro-bumps.