In situ metalorganic chemical vapor deposition of Al2O3 on N-face GaN and evidence of polarity induced fixed charge

The in situ metalorganic chemical vapor deposition (MOCVD) of Al2O3 dielectrics on N-face GaN is reported. The near-interface fixed charges are measured by using capacitance-voltage techniques on a metal-oxide-semiconductor (MOSCAP) structure, and the results are compared with those obtained on Ga-face MOSCAPs with the same in situ MOCVD Al2O3 dielectrics. The influence of GaN polarity as well as other possible mechanisms on the formation of fixed charge are identified and discussed. (C) 2014 AIP Publishing LLC.