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. 27, 2009
Filed:
Sep. 08, 2006
Sam-hyo Hong, Spänga, SE;
Henrik Hoyer, Los Gatos, CA (US);
Jeffrey Hume, El Granada, CA (US);
Infineon Technologies AG, Munich, DE;
Abstract
In a circuit, an integrated circuit package and methods for attaching integrated circuit dies or discrete power components to flanges of integrated circuit packages, each of the integrated circuit dies is sawed from a wafer. The thickness of the wafer is reduced by mechanical grinding, applying an isotropic wet chemical etching to the wafer to eliminate crystal defects, evaporating adhesion and diffusion barrier metals on the backside of the wafer, evaporating Au and Sn on the backside of the wafer, wherein the weight proportion of Au is equal to or larger than 85%, sawing the wafer into the circuit dies, and soldering each of the circuit dies to a respective flange of an integrated circuit package.