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:
Sep. 02, 2003
Filed:
Mar. 13, 2000
Satoshi Takenaka, Suwa, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
The invention provides an active matrix substrate which allows the film quality of a MIS transistor to be evaluated easily and accurately, an electrooptical device using such an active matrix substrate, and a method of producing such an active matrix substrate. On an active matrix substrate, a film quality evaluation region with a size of 1 mm square is formed at a location where neither an image display area, a scanning line driving circuit, a data line driving circuit, nor a signal line is formed. A semiconductor film (silicon film) for film quality evaluation is formed in the film quality evaluation region using the same layer as a heavily doped source/drain region of a TFT and doped with the same impurity at the same concentration as the source/drain region. The semiconductor film for film quality evaluation is exposed through an opening formed through interlayer insulating films, so that it is possible to immediately start evaluation of the film equality.