Ion beam induced epitaxy of deposited amorphous Si and Si-Ge films

Abstract

The epitaxial recrystallization of amorphous electron beam deposited silicon and silicon-germanium layers on 〈100〉 silicon substrates was induced by a 2.5 MeV Ar beam irradiation in the temperature range of 200–400 °C. Even in films with bulk oxygen concentration of 0.5 at. %, layer-by-layer regrowth was observed with an order of magnitude reduction in growth rate when compared to clean, implanted amorphous silicon. Irradiation of codeposited Si-Ge amorphous layers results in the layer-by-layer regrowth of a Si88Ge12 alloy. Ion beam assisted epitaxy of Si and Si-Ge was found to be sensitive to interfacial cleanliness, but layer-by-layer regrowth was observed for samples that did not demonstrate regrowth under conventional furnace annealing.