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:
Jan. 05, 1999
Filed:
Apr. 18, 1997
Applicant:
Inventors:
Assignee:
Semiconductor Energy Laboratory Co., Ltd., Kanagawa, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ; G02F / ;
U.S. Cl.
CPC ...
349 42 ; 349 43 ; 349110 ; 349111 ; 349138 ;
Abstract
In an active matrix type liquid crystal electro-optical device using thin-film transistors, a metal film is formed on a transparent electrode that is opposed to the thin-film transistors. The metal film is oxidized by anode oxidation method using the electrode as an anode, to form a metal oxide film that serves as a short circuit preventing film. Alternatively, after a grid-shaped mask is formed on the metal film, the metal film is oxidized using the electrode as an anode, the mask is removed, and the metal film is again anode-oxidized, to form a non-oxidized portion. Thus, transparent and opaque regions, i.e., a black matrix is formed.