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. 23, 2010
Filed:
Feb. 05, 2007
Shahram Mostafazadeh, San Jose, CA (US);
Viraj Patwardhan, Santa Clara, CA (US);
Shahram Mostafazadeh, San Jose, CA (US);
Viraj Patwardhan, Santa Clara, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
Improved protective metallization is described for bumped copper-top semiconductor chips. The semiconductor device includes a top wafer fabrication passivation layer with openings through which contact pads are exposed. A patterned copper layer is formed over the passivation layer and is electrically coupled to the contact pads through the openings. A metallic barrier layer is provided between the contact pads and the patterned copper layer. A titanium metallization layer overlies the patterned copper layer and cooperates with the barrier layer to envelop the copper layer in the regions of the contact pads. An aluminum metallization layer overlies the titanium metallization layer. An electrically insulating protective layer overlies the aluminum metallization and passivation layers. The protective layer includes openings in which underbump metallization stacks are formed. Each underbump metallization stack electrically connects to the aluminum metallization layer through an opening in the protective layer. Solder bumps adhere to the underbump metallization stacks.