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. 04, 1999
Filed:
Feb. 27, 1997
Applicant:
Inventor:
Shigehisa Yamamoto, Tokyo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G01R / ; H01L / ;
U.S. Cl.
CPC ...
324537 ; 3241581 ; 257758 ;
Abstract
Center-to-center spacings (L.sub.1, L.sub.2, L.sub.3, L.sub.4, . . . ) of adjacent holes (5) in a hole chain (6) are set to values not less than five times a Blech length. This setting causes two parameters (MTF and .sigma.) of a logarithmic normal distribution used as a failure distribution for EM lifetime prediction to be constant independently of the center-to-center spacings, permitting stable EM lifetime prediction of the hole chain. Further, setting the length of each of extension interconnect wires (2) to a value not greater than the Blech length prevents voids from being created in the extension interconnect wires (2).