Solid-phase epitaxy from 0.2-thick amorphous films, which had been prepared by As ion implantation, was produced by exposure to synchrotron radiation. The substrate temperature during this process (less than 430C) was insufficient for thermal crystallization. It was found that the photon flux threshold for such X-ray assisted crystallization was 5 x 1015/mm2. The threshold was attributed to a transition from a diffusion-limited rate to a reaction-limited rate for the annihilation of vacancies.

T.Katoh, H.Yamada, F.Sato, Y.Hirano, J.Chikawa: Journal of Vacuum Science and Technology A, 1996, 14[4], 2443-7