Silicon epitaxial growth on (100) patterned oxide wafers at 800 °C by ultralow-pressure chemical vapor deposition

Abstract
This letter presents for the first time the results of low‐temperature (800 °C) silicon epitaxial growth on (100) patterned oxide wafers by ultralow‐pressure chemical vapor deposition. The epitaxial layers were deposited at 6 mTorr of SiH4 following an in situ argon sputter cleaning step. The films on the exposed single‐crystal silicon islands were epitaxial with high structural quality, while those on the oxide were polycrystalline with columnar grains. The growth rate of epitaxial silicon was 2.5 times that of polycrystalline silicon. The transition region between the epitaxial and polycrystalline silicon deposited is very sharp, confined to a boundary which is parallel to the growth direction, and located on the edges of the exposed silicon islands.