Effects of substrate temperature on the orientation of ultrahigh vacuum evaporate Si and Ge films

Abstract
Studies of texture in ultrahigh vacuum deposited Si and Ge films show a (220) preferred orientation for the as-prepared polycrystalline films. On the other hand, amorphous silicon (a-Si) followed by thermal crystallization exhibits a (111) orientation when contamination with oxygen is allowed prior to annealing. Oxygen incorporation is only indirectly involved in promoting the (111) preferred orientation via high annealing temperature. Preferred orientation is absent when contamination is avoided. In contrast, thermally crystallized a-Ge films show no preferred orientation regardless of oxygen contamination.