An examination of facet formation during solid phase epitaxy of line-shaped amorphized regions in (001) and (011) Si

The shapes of the recrystallization fronts observed during solid phase epitaxy (SPE) in line-shaped amorphized Si (a-Si) regions in single-crystal (001) and (011) Si are shown to exhibit a complex time evolution inconsistent with simple models in which regrowth behavior is determined exclusively by the competition between fixed-growth-rate lateral and vertical SPE. We find that the main features of our data for 〈110〉-aligned a-Si lines may be explained by the propensity of the lateral and vertical growth fronts to form stable a-Si {111} interfaces at their edges. These same a-Si {111} interfaces have been previously implicated as the root cause of the trench-edge defects produced during the recrystallization of patterned a-Si regions bounded laterally by oxide-filled trenches. An extension of a nanofacet model recently developed to explain the trench-edge defects is shown to explain many of the observed recrystallization behaviors. © 2007 American Institute of Physics.