Layer-by-Layer Growth of AlAs Buffer Layer for GaAs on Si at Low Temperature by Atomic Layer Epitaxy

We developed a novel growth technique for AlAs on GaAs and Si substrates at a low temperature of 150°C. The low-temperature growth was achieved using atomic layer epitaxy (ALE) with trimethylamine alane as a group III source. Layer-by-layer growth of one monolayer per ALE cycle with a self-limiting effect was obtained on both substrates. Surface morphology of GaAs on Si was improved by the use of this AlAs as a buffer layer. The degradation of crystal quality, expected due to the growth of the GaAs active layer on the low-temperature buffer layer, did not occur.