Heteroepitaxial silicon growth on polycrystalline MoSi2

Abstract

Heteroepitaxial silicon was grown on polycrystalline MoSi2 by electron beam evaporation at 800 °C in an ultrahigh vacuum. The silicon films with a thickness between 2 and 12 μm grew with either an (111) or (233) orientation. The growth and morphology of the silicon deposit was studied as a function of temperature and the partial pressure of oxygen. Depositions at substrate temperatures of 950 and 1100 °C exceeded the epitaxial temperatures producing films that had faceted grains measuring 2–8 μm in cross section along with larger grains measuring nearly 200 μm across. The introduction of 10−10 Torr partial pressure of oxygen during deposition at 1100 °C changed the morphology and eliminated the large grains. The presence of oxygen at 800 °C prevented epitaxial growth.