Epitaxial growth of cubic SiC thin films on silicon using single molecular precursors by metalorganic chemical vapor deposition

Abstract

Heteroepitaxial cubic SiC thin films have been deposited on silicon substrates at temperatures in the range of 750–1000 °C using single molecular precursors by the metalorganic chemical vapor deposition (CVD) method. Single-crystalline, crack-free, stoichiometric cubic SiC films were successfully grown on both Si(001) and Si(111) substrates without surface carbonization at as low as temperature of 920 °C with 1,3-disilabutane, H3Si–CH2–SiH2–CH3, as a liquid single source precursor which contains silicon and carbon in 1:1 ratio. Cubic SiC thin films highly oriented in the [001] direction were also obtained on Si(001) using either a liquid mixture of 1,3,5-trisilapentane (TSP), H3Si–CH2–SiH2–CH2–SiH3, and 2,4,6-trisilaheptane (TSH) at 980 °C or 2,6-dimethyl-2,4,6-trisilaheptane (DMTSH), H3C–SiH(CH3)–CH2–SiH2–CH2–SiH(CH3)–CH3 at 950 °C without carrier gas. These growth temperatures were much lower than conventional CVD growth temperatures, and this is a report of cubic SiC film growth using the single molecular precursors of trisilaalkanes (i.e., DMTSH and TSP+TSH). The as-grown SiC films were characterized by in situ reflection high-energy electron diffraction and by ex situ x-ray diffraction, transmission electron diffraction, scanning electron microscopy, Auger electron spectroscopy, and Rutherford backscattering spectroscopy