Observation of explosive crystallization during excimer laser annealing using in situ time-resolved optical reflection and transmission measurements

XeF excimer laser-induced melting and recrystallization of amorphous silicon was investigated using in situ on-line time-resolved reflection and transmission measurements with a nanosecond time resolution. Explosive crystallization was observed for 900 Å thick amorphous silicon on SiO2 deposited on non-alkali glass substrate upon 25 ns pulse duration of excimer laser by continuous-wave He-Ne probe laser. Three distinct regrowth regimes were investigated on the basis of various excimer laser fluences. Scanning electron microscopy, Raman spectroscopy and atomic force microscopy were used to evaluate the excimer laser-irradiated region of the sample. Grain size, surface roughness and melt duration as a function of various laser fluences are also determined.