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:
May. 15, 2012
Filed:
Jun. 12, 2009
Michihiro Kawashita, Hitachinaka, JP;
Yasuhiro Yoshimura, Kasumigaura, JP;
Naotaka Tanaka, Kasumigaura, JP;
Takahiro Naito, Duesseldorf, DE;
Takashi Akazawa, Musashimurayama, JP;
Michihiro Kawashita, Hitachinaka, JP;
Yasuhiro Yoshimura, Kasumigaura, JP;
Naotaka Tanaka, Kasumigaura, JP;
Takahiro Naito, Duesseldorf, DE;
Takashi Akazawa, Musashimurayama, JP;
Renesas Electronics Corporation, Kanagawa, JP;
Abstract
When a through-hole electrode and a rear-surface wire are formed on a rear surface of a chip, a convex portion is formed on the rear surface of the chip due to a rear-surface wiring pad which is a part of the through-hole electrode and the rear-surface wire. This causes the air leakage when the chip is sucked, and therefore, the reduction of the sucking force of the chip occurs. A concave portion is formed in advance in a region where a rear-surface wiring pad and a rear-surface wire are formed. The rear-surface wiring pad and the rear-surface wire are provided inside the concave portion. Thus, a flatness of the rear surface of the chip is ensured by a convex portion caused by thicknesses of the rear-surface wiring pad and the rear-surface wire, so that the reduction of the sucking force does not occur when the chip is handled.