Growth of InAs on Si substrates at low temperatures using metalorganic vapor phase epitaxy

Abstract

The growth behavior of InAs on Si using metalorganic vapor phase epitaxy (MOVPE) was studied. The large lattice mismatch of InAs to Si, ∼12%, results in island formation under typical MOVPE growth conditions, which prevents the development of the thin coherent films of InAs needed for high-speed device applications. The growth of InAs at low temperature is expected to lead to rapid nucleation and low surface mobility, resulting in the formation of a coherent film at low thicknesses. This study explored the growth behavior of InAs on Si at low temperatures, i.e. <350 °C and varying V/III ratio. InAs films were grown on {1 0 0}-, {1 1 1}- and {2 1 1}-oriented Si substrates using trimethyl indium, tertiary butyl arsine and AsH 3. Small islands ranging from 15 to 30 nm form on the samples at growth temperatures <325 °C. Subsequent annealing of this thin layer at 600 °C for 5 min leads to island coarsening. High-resolution X-ray diffraction, atomic force microscopy and scanning electron microscopy were used to characterize InAs layer grown on Si.