Title :
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
fDate :
11/1/1997 12:00:00 AM
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;
Journal_Title :
Electron Devices, IEEE Transactions on
