On the super lateral growth phenomenon observed in excimer laser-induced crystallization of thin Si films

This letter reports on the experimental findings, and provides a theoretical description of the super lateral growth (SLG) phenomenon observed in the pulsed laser-induced solidification of amorphous thin Si films on SiO ₂. Experimentally, we report and elaborate on the isolated single-crystal disk structure that is observed at the upper threshold of the SLG regime; the structure is revealed as an important microstructural feature for understanding the phenomenon. A theoretical discussion of the SLG phenomenon is provided in terms of the key factors that are suggested by our model - the interface response function of the solid, the nucleation kinetics of the solid, and a highly transient lateral-thermal profile near the solid-melt interface. Our model and analysis point out the important inadequacies associated with the vertical solidification rate/temperature gradient model, which is currently being utilized to explain the excimer laser crystallization of thin Si films on SiO₂.