Atomic layer epitaxy of MnAs on GaAs(0 0 1)

Atomic layer epitaxy (ALE) of MnAs on GaAs(0 0 1) has been investigated using bismethylcyclopentadienylmanganese (CH ₃C ₅H ₄) ₂Mn and trisdimethylaminoarsine As[N(CH ₃) ₂] for manganese and arsenic precursors, respectively. The α-MnAs layer of "type B" orientation was successfully grown by an alternative source supply with a wide growth temperature range from 320 to 500 °C. The grown layer showed a smooth surface morphology, reflecting the self-limiting growth. The decreased growth rate was observed below 350 °C, which was caused by the decreased reaction rate of As[N(CH ₃) ₂] ₃ on the growing surface. A clear self-limiting mechanism was realized at higher growth temperatures but the saturation thickness was 9.5×10 ^-2 nm/cycle, which was attributed to the formation of a stable surface-reconstruction of manganese stabilized surface.