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:
Mar. 08, 2011
Filed:
Jan. 05, 2007
Kiyoshi Ouchi, Kodaira, JP;
Mutsuko Hatano, Kokubunji, JP;
Takeshi Sato, Kokubunji, JP;
Mitsuharu Tai, Kokubunji, JP;
Kiyoshi Ouchi, Kodaira, JP;
Mutsuko Hatano, Kokubunji, JP;
Takeshi Sato, Kokubunji, JP;
Mitsuharu Tai, Kokubunji, JP;
Hitachi Displays, Ltd., Chiba, JP;
Abstract
An image display device capable of high-resolution and smooth moving image display, equipped with TFTs in an n-type (or p-type) semiconductor layer with a high on-off ratio and a low resistance. In polysilicon crystallization by laser annealing, an n-type (or p-type) semiconductor layer with a low resistance is produced by performing the following processes in order: implanting nitrogen (N) ions into an amorphous silicon precursor semiconductor film; laser crystallization; implanting n-type (or p-type) dopant ions; and annealing for dopant activation. When fabricating TFTs, this low-resistance semiconductor layer is used to form a source and a drain. Since C, N, and O impurities decrease the mobility of the TFTs, polysilicon is used in which the contaminants concentrations meet the following conditions: carbon concentration ≦3×10cm, nitrogen concentration ≦5×10cm, and oxygen concentration ≦3×10cm.