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. 12, 1991
Filed:
Mar. 22, 1988
Applicant:
Inventor:
Shigeru Shirai, Nagahama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ; H01L / ; H01L / ;
U.S. Cl.
CPC ...
357 237 ; 357-2 ; 437 84 ; 437 87 ;
Abstract
An improved field effect thin film transistor characterized in that the semiconductor layer being formed from a polycrystal silicon film: said layer containing at least hydrogen atom and fluorine atom except silicon atom layer: and the concentration of said hydrogen atom or said fluorine atom being distributed in the thickness direction in the state that it being relatively thick in a layer region in the side of the substrate and relatively thin in a layer resion in the opposite side. A process for preparing the above field effect thin film transistor, characterized in that the semiconductor layer is formed by: