Enhancement in Photoconductivity of a-Si thin Films by Annealing and Texturing Technique with the Third Harmonic Output from a Pulsed Nd3+:YAG Laser

Influence of the third harmonic pulsed Nd3+:YAG laser on the formation of a polycrystalline-silicon (poly-Si) on a-Si thin film with thickness of 1000 nm and 400nm in water and air ambience was investigated. In order to induce texturing of surface along with annealing, laser beam overlap technique with different percentages of spot overlap was used. Crystalline characteristics and electrical characteristics were studied to confirm the extent of crystallization. The crystalline characteristics of the film obtained with the Gaussian and the flat-top beam profiles were comparable for higher percentage of overlapping. Based on the theoretical modeling, the laser treatment without the ablation with the third output from the Nd3+:YAG laser was limited to the a-Si film thickness up to 800 nm. This was in qualitative agreement with the experimental observations.