Reduction of native oxides on GaAs during atomic layer growth of AI_2O_3

摘要

The reduction of surface "native" oxides from GaAs substrates following reactions with trimethylalummum (TMA) precursor is studied using medium energy ion scattering spectroscopy (MEIS) and x-ray photoelectron spectroscopy (XPS). MEIS measurements after one single TMA pulse show that ～65% of the native oxide is reduced, confirmed by XPS measurement, and a 5 A thick oxygen-rich aluminum oxide layer is formed. This reduction occurs upon TMA exposure to as-received GaAs wafers.