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. 30, 2001
Filed:
Feb. 03, 1999
Ling-Chen Kung, Hsinchu, TW;
Hsu-Tien Hu, Hsinchu, TW;
Ruoh-Huey Uang, Hsinchu, TW;
Szu-Wei Lu, Hsinchu, TW;
Chun-Yi Kuo, Hsinchu, TW;
Industrial Technology Research Institute, Hsin Chu, TW;
Abstract
A method for forming solder balls that have improved height on an electronic substrate such as a silicon wafer and devices formed are disclosed. In the method, after solder bumps are deposited by a conventional method such as evaporation, electroplating, electroless plating or solder paste screen printing, the solder bumps are reflown on the substrate in an upside down position such that the gravity of the solder material pulls down the solder ball and thereby increasing its height after the reflow process is completed. It has been found that a minimum of 5%, and preferably about 10% height increase has been achieved. Another benefit achieved by the present invention novel method which is associated with the increase in the solder ball height is a corresponding increase in the pitch distance between the solder balls by at least 5%.