In‐situ X‐ray photoelectron spectroscopy of trimethyl aluminum and water half‐cycle treatments on HF‐treated and O3‐oxidized GaN substrates

We have investigated the effect of trimethyl aluminum (TMA) and water (H2O) half‐cycle treatments on HF‐treated, and O3‐oxidized GaN surfaces at 300 °C. The in‐situ X‐ray photoelectron spectroscopy results indicate no significant re‐growth of Ga–O–N or self‐cleaning on HF‐treated and O3‐oxidized GaN substrates with exposure to water and TMA. This result is different from the self‐cleaning effect of Ga2O3 seen on sulfur‐treated GaAs or InGaAs substrates. O3 causes aggressive oxidation of GaN substrate and direct O–N bonding compared to H2O. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)