The Epitaxial Growth and Properties of Silicon on Stoichiometric Spinel and Sapphire Substrates Using Silane‐Helium Mixtures vs. Silane‐Hydrogen Mixtures

Abstract

Epitaxial growth of silicon on (111) and (100) stoichiometric spinel, , (0001), and sapphire using silane in helium has been studied. (100) Si seems to be more compatible with sapphire than (111) Si, and exactly the opposite is true with sloichiometric spinel. Higher growth rate is preferred for epitaxial growth on sapphire and lower growth rate is favored for growth on stoichiometric spinel. Silicon films grown in hydrogen tend to have a smoother surface than that grown in helium, but larger contamination and interdiffusion effects. Lower optimum growth temperatures have also been observed for the silicon growth in helium than in hydrogen.Effects of various growth parameters on the properties of the silicon layer using silane in helium were investigated. Hall mobilities comparable to bulk Si were realized in p‐type films on (111) spinel. Hall mobility dependence, for both holes and electrons, on film thickness was found to be nearly constant for Si layers on spinel beyond 1 µm. The effect of stress on the mobility of (111) and (100) Si has been discussed.