Title :
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
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;
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
DOI :
10.1109/ICSICT.2006.306181
