Optimization of excimer laser annealing on low temperature polysilicon for thin film transistor applications

Author

Cheng, T.C. ; Chang, W.C. ; Yarn, K.F. ; Lo, C.F. ; Kuo, J.K.

Author_Institution

Dept. of Electron. Eng., Southern Taiwan Univ. of Technol., Tainan

fYear

2006

fDate

23-26 Oct. 2006

Firstpage

266

Lastpage

268

Abstract

Excimer laser annealing (ELA) amorphous silicon (a-Si) to poly-silicon (poly-Si) in different gas environment, i.e. N₂ or N₂ mixed O₂:2%, is studied for the fabrication of thin film transistors (TFTs). Influence of laser power on the surface morphology, grain size and height of gibbous grain is investigated. The variation of threshold laser power for the generation of surface ablation in N₂ and N₂:98% mixed O₂:2% environment is also discussed. From experiment, it is found that the combination of O₂:2% enhance the threshold laser power for the generation of surface ablation from 320mJ/cm² to 390mJ/cm ². In the condition of average grain over 0.25mum, the process window is 30mJ/cm²for N₂, but is 50mJ/cm ² for N₂ mixed O₂:2% environment

Keywords

amorphous semiconductors; elemental semiconductors; excimer lasers; grain size; laser ablation; laser beam annealing; nitrogen; oxygen; silicon; surface morphology; thin film transistors; N₂; O₂; Si; TFT; amorphous silicon; excimer laser annealing; gas environment; grain size; low temperature polysilicon; surface ablation; surface morphology; thin film transistor; threshold laser power; Annealing; Gas lasers; Laser ablation; Laser applications; Power generation; Power lasers; Surface emitting lasers; Surface morphology; Temperature; Thin film transistors;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State and Integrated Circuit Technology, 2006. ICSICT '06. 8th International Conference on

Conference_Location

Shanghai

Print_ISBN

1-4244-0160-7

Electronic_ISBN

1-4244-0161-5

Type

conf

DOI

10.1109/ICSICT.2006.306181

Filename

4098081