Silane and Ammonia Surface Passivation Technology for High-Mobility In0.53Ga0.47As MOSFETs

We report the integration of silane and ammonia (SiH4+ NH3) surface passivation technology to realize high-quality gate stack on a high-mobility In0.53Ga0.47As compound semiconductor. Vacuum anneal at 520°C desorbs the native oxide while preserving the surface morphology and material composition of In0.53Ga0.47As. By incorporating SiH4+ NH3passivation, a thin silicon oxynitride (SiOxNy) interfacial layer was formed during high-kdielectric deposition. In0.53Ga0.47As n-MOSFETs with SiH4+ NH3passivation demonstrate significantly reduced subthreshold swing and off-state leakage currentIoffin comparison with control In0.53Ga0.47As n-MOSFETs without passivation. This is due to significant reduction of interface state densityDit. Improvement in carrier mobility over the control In0.53Ga0.47As n-MOSFETs was also achieved with SiH4+ NH3passivation.