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:
Oct. 13, 2009
Filed:
Oct. 24, 2005
Raj N. Master, San Jose, CA (US);
Junaida A. Bakar, Penang, MY;
Diong H. Ding, Penang, MY;
Srinivasan Parthasarathy, Santa Clara, CA (US);
Raj N. Master, San Jose, CA (US);
Junaida A. Bakar, Penang, MY;
Diong H. Ding, Penang, MY;
Srinivasan Parthasarathy, Santa Clara, CA (US);
GlobalFoundries Inc., Grand Cayman, KY;
Abstract
A method for forming a solder joint for a package arrangement with a dispersed Sn microstructure provides a flip chip on a package, with a flip chip having solder bumps to be connected by eutectic solder joints to pads on the package. The eutectic solder is reflowed at a solder bump/pad interface with a eutectic reflow profile that is configured to achieve eutectic solder joints having substantially evenly distributed Sn grains. The eutectic reflow profile includes an increased cooling rate and decreased hold time with a higher peak temperature. A defined ratio of the pad openings in the solder mask to the under bump metallurgy is provided. The eutectic reflow profile and the defined ratio prolong fatigue life in the package arrangement.