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. 14, 2008
Filed:
Aug. 20, 2002
Norio Kainuma, Kawasaki, JP;
Shunji Baba, Kawasaki, JP;
Hidehiko Kira, Kawasaki, JP;
Toru Okada, Kawasaki, JP;
Norio Kainuma, Kawasaki, JP;
Shunji Baba, Kawasaki, JP;
Hidehiko Kira, Kawasaki, JP;
Toru Okada, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An apparatus and method for improving the underfill filling of a semiconductor chip elementwhich is ultrasonically bonded to and mounted on a circuit board. A semiconductor chip elementincludes a silicon chipand a group of stud bumpsformed on a bottom surfaceof the chip. Signal stud bumpsare made of gold while power stud bumpsground stud bumpsand dummy stud bumpsare all made of a gold-palladium alloy, which are harder than the signal stud bumpsand thus do not deform easily during ultrasonic treatment. Therefore, in a state in which the semiconductor chip elementis mounted, a gap of approximately 30 μm is maintained between the bottom surfaceof the chipand a top surface of the circuit boardon which the semiconductor chip elementis mounted.