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:
Jan. 22, 2008
Filed:
Mar. 11, 2005
Yanping LI, Mountain View, CA (US);
Jriyan Jerry Chen, Santa Clara, CA (US);
Lisa Yang, Saratoga, CA (US);
Yanping Li, Mountain View, CA (US);
Jriyan Jerry Chen, Santa Clara, CA (US);
Lisa Yang, Saratoga, CA (US);
Applied Materials, Inc., Santa Clara, CA (US);
Abstract
A nickel silicon alloy barrier layer formed between a metal bonding pad on an integrated circuit and a tin-based solder ball, for example, a lead-free solder. The nickel silicon alloy contains at least 2 wt % silicon and preferably less than 20 wt %. An adhesion layer may be formed between the barrier layer and the bonding pad. For copper metallization, the adhesion layer may contain titanium or tantalum; for aluminum metallization, it may be aluminum. The nickel silicon alloy may be deposited by magnetron sputtering. Commercially available NiSi% sputter targets have provided a superior under-bump metallization (UBM) with lead-free tin solder bumps. Dopants other than silicon/may be used to reduce the magnetic permeability and provide other advantages of the invention.