Gigantic crystal grain by excimer laser with a pulse duration of 200 ns and its application to TFT

The large grain growth by excimer laser annealing was observed at multi-sho ts with a long laser pulse duration of 200 ns. The grain size of the polycr ystalline Si increases up to similar to 1.5 mu m with 20 shots at a laser e nergy density of 650 mJ/cm(2), and (111) orientation is dominant. The dark conductivity and conductivity activation energy of the poly-Si were 1.47x10 (-4) Slcm and 0.54 eV, respectively. The TFT with the poly-Si exhibited a f ield effect mobility of 215 cm(2)/Vs, a threshold voltage of -0.5 V and a s ubthreshold slope of 0.9 V/dec.