In situ study of MgO on GaAs (001) for integrating thin film ferroelectrics with semiconductors

Abstract

Formation of thin film MgO on the (001) GaAs surface is investigated using molecular beam epitaxy (MBE) and reflection high-energy electron diffraction (RHEED). The MBE system is equipped with a shuttered magnesium effusion cell and an electronically controlled oxygen source. The evolution of the MgO layer is monitored in situ by RHEED. The GaAs substrate is held at 100 °C while exposed simultaneously to magnesium and oxygen fluxes. The resulting MgO films are polycrystalline; however, RHEED patterns indicate a preferred growth orientation. Current growth conditions are examined and future work is proposed.