Silane and ammonia surface passivation technology for high-mobility In 0.53Ga0.47As MOSFETs

Abstract

We report the integration of silane and ammonia SiH4 + NH 3) 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 In0.53Ga 0.47As. By incorporating SiH4 + NH3 passivation, a thin silicon oxynitride (SiOxNy) interfacial layer was formed during high-κ dielectric deposition. In 0.53Ga0.47As n-MOSFETs with SiH4 + NH 3 passivation demonstrate significantly reduced subthreshold swing and off-state leakage current Ioff in comparison with control In 0.53Ga0.47As n-MOSFETs without passivation. This is due to significant reduction of interface state density Dit. Improvement in carrier mobility over the control In0.53Ga0.47As n-MOSFETs was also achieved with SiH4 + NH3 passivation. © 2010 IEEE.