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:
Jun. 29, 1993
Filed:
Apr. 15, 1992
Makio Okada, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
The present invention relates to a leadframe having slits around a semiconductor device forming area to absorb distortion or warpage of the leadframe because of the difference in the coefficients of thermal expansion of the leadframe and a sealing resin. The present invention is directed to limiting shifting of the outer leads caused by distortion or contraction of the leadframe and preventing cutting of the outer leads in a tie bar cutting process. To achieve these goals, positioning holes are provided on the inner portion of the leadframe in the vicinity of the tie bars at the three corners of the semiconductor device forming area but not at a corner where the resin injecting portion is located.