Electrical characteristics of poly-Si TFT´s with smooth surface roughness at oxide/poly-Si interface

Author

Min, Byung-Hyuk ; Park, Cheol-Min ; Han, Min-Koo

Author_Institution

Dept. of Electr. Eng., Seoul Nat. Univ., South Korea

Volume

44

Issue

11

fYear

1997

fDate

11/1/1997 12:00:00 AM

Firstpage

2036

Lastpage

2038

Abstract

We have fabricated a polycrystalline silicon thin film transistor (poly Si TFT) using a novel oxidation method, which improves the surface roughness at the interface between the poly-Si layer and the gate oxide layer. Compared with the poly-Si TFT´s fabricated by the conventional oxidation method, the proposed poly-Si TFT exhibits the remarkable enhancement of the electrical parameters, such as the subthreshold swing and the threshold voltage. It is observed that the proposed poly-Si TFT has a higher dielectric strength, and the device characteristics are not degraded significantly after an electrical stress. The improvement of the surface roughness at oxide/poly-Si interface is found to he critical to enhance the device performance

Keywords

characteristics measurement; electric breakdown; electric strength; elemental semiconductors; oxidation; silicon; surface topography; thin film transistors; Si; device characteristics; device performance; dielectric strength; electrical parameters; gate oxide layer; oxidation method; oxide/polysilicon interface; polysilicon TFTs; smooth surface roughness; subthreshold swing; threshold voltage; Degradation; Dielectric breakdown; Electric variables; Oxidation; Rough surfaces; Silicon; Stress; Surface roughness; Thin film transistors; Threshold voltage;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.641379

Filename

641379