06909114 is referenced by 187 patents and cites 57 patents.

There is provided a thin film transistor having improved reliability. A gate electrode includes a first gate electrode having a taper portion and a second gate electrode with a width narrower than the first gate electrode. A semiconductor layer is doped with phosphorus of a low concentration through the first gate electrode. In the semiconductor layer, two kinds of n−-type impurity regions are formed between a channel formation region and n+-type impurity regions. Some of the n−-type impurity regions overlap with a gate electrode, and the other n−-type impurity regions do not overlap with the gate electrode. Since the two kinds of n−-type impurity regions are formed, an off current can be reduced, and deterioration of characteristics can be suppressed.

Title
Semiconductor device having LDD regions
Application Number
9/433705
Publication Number
6909114 (B1)
Application Date
November 4, 1999
Publication Date
June 21, 2005
Inventor
Shunpei Yamazaki
Tokyo
JP
Agent
Robinson Intellectual Property Law Office P C
Eric J Robinson
Assignee
Semiconductor Energy Laboratory
JP
IPC
H01L 031/113
H01L 031/062
H01L 029/94
H01L 029/04
H01L 029/76
View Original Source