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:
Apr. 03, 2001
Filed:
Jan. 13, 1999
Young Hee Byun, Novi, MI (US);
Yiwei Lu, Ann Arbor, MI (US);
OIS Optical Imaging Systems, Inc., Northville, MI (US);
Abstract
A TFT structure includes a variably doped contact layer system in order to reduce leakage current characteristics and increase mobility of the TFT. Such TFTs may be utilized in, for example, X-ray imagers or liquid crystal displays. In certain embodiments, the contact layer system is lightly doped adjacent a semiconductor or channel layer, and is more heavily doped adjacent the source/drain electrodes. The variation in doping density of the contact layer system may be performed in a step-like manner, gradually, continuously, or in any other suitable manner. In certain embodiments, the contact layer system may include a single layer which is deposited over an intrinsic semiconductor layer, with the amount of dopant gas being used during the deposition process being adjusted through the deposition of the single layer so as to cause the doping density to vary (increase or decrease) throughout the thickness of the system/layer.