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:
Feb. 05, 2002
Filed:
Apr. 27, 1999
Keisuke Hatano, Tokyo, JP;
Yasutaka Nakashiba, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
An image pickup element unit and peripheral circuits are formed on a common semiconductor substrate. The image pickup element unit comprises sensors which converts incident lights into charges. The peripheral circuits comprise contact holes therein and transfer signals to external components via the contact holes. A tungsten film which works as both a photo shield and a barrier metal film is formed on the semiconductor substrate so that each of the sensors has its opening portion and the contact holes are filled with the tungsten film. An aluminum film which works as wiring is formed on the tungsten film filing the contact holes. A tungsten silicide layer is formed at conjunction portion between the tungsten film in the contact holes and the semiconductor substrate. Contacts comprising the tungsten film and the tungsten silicide layer show excellent ohmic contact characteristics.