Influence of gate metallization processes on the electrical characteristics of high-k/In0.53Ga0.47As interfaces

The influence of different gate metal deposition processes on the electrical characteristics of dielectric/III-V interfaces is investigated. Al2O3 and HfO2 dielectrics are grown on In0.53Ga0.47As channels and top metal electrodes are deposited by either thermal evaporation or electron beam deposition. It is shown that metal-oxide-semiconductor capacitors with electron beam evaporated electrodes exhibit substantially larger midgap interface trap densities than those with thermally evaporated electrodes. The damage caused by electron beam metallization can be mitigated by subsequent, long anneals in forming gas. (C) 2011 American Vacuum Society. [DOI: 10.1116/1.3610989]