Epitaxial Growth of GaAs at One to Two Monolayers per Cycle by Alternate Supply of GaCl3 and AsH3

Atomic layer growth of GaAs using GaCl3 and AsH3 was carefully investigated. Precise measurements revealed that the growth rate depended on the growth temperature and increased from 1 monolayer/cycle at 300°C to nearly 2 monolayers/cycle at 450°C for alternating supply of GaCl3 and AsH3, contrary to what we had previously reported. When the growth temperature was less than 300°C, GaAs deposited both on a GaAs substrate and on the SiO2 mask and the growth rate was about 0.7 monolayers/cycle. Raman spectra of the grown layers indicated that GaAs grown at above 300°C was a single crystal but that GaAs deposited below 300°C was polycrystalline.