Improvement of the reliability of amorphous silicon transistors by conduction-band tail width reduction

Author

GadelRab, Serag M. ; Chamberlain, Savvas G.

Author_Institution

Dept. of Electr. & Comput. Eng., Waterloo Univ., Ont., Canada

Volume

45

Issue

10

fYear

1998

fDate

10/1/1998 12:00:00 AM

Firstpage

2179

Lastpage

2186

Abstract

We present theoretical and experimental evidence showing that bias induced threshold voltage degradation of a-Si:H transistors is reduced by decreasing the width of the conduction-band tail. We show that transistors which are made using a thick (0.5 μm) a-Si:H layer possess a narrower conduction-band tail compared to transistors made using thin (0.05 μm) a-Si:H layers. We find that bias-induced threshold voltage degradation decreases by a factor of two for thick-layered TFTs compared with conventional, thin-layered TFTs. Finally, we present device design guidelines for improving the reliability of a-Si:H TFTs including several possible device designs for achieving further improvements in the reliability of a-Si:H TFTs

Keywords

amorphous semiconductors; band structure; elemental semiconductors; hydrogen; semiconductor device reliability; thin film transistors; 0.05 micron; 0.5 micron; Si:H; amorphous semiconductors; bias induced threshold voltage degradation; conduction-band tail width reduction; device designs; reliability; thick-layered TFTs; thin-layered TFTs; Amorphous silicon; Circuits; Degradation; Guidelines; Image sensors; Stability; Switches; Tail; Thin film transistors; Threshold voltage;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.725252

Filename

725252