Study on electrical properties of HfTiON and HfTiO gate dielectric Ge MOS capacitors with wet-NO surface pretreatment

摘要

Reactive co-sputtering is employed to prepare HfTiO/GeOxNy and HfTiON/GeOxNy stack gate dielectrics by using wet NO or N2O surface pretreatment. The experimental results show that the wet NO pretreatment can lead to excellent interface properties, gate leakage properties and device reliability, especially for HfTiON/GeOxNy stack gate dielectrics. The involved mechanisms lie in N-barrier role and suitable N incorporation in GeOxNy interlayer, effectively preventing further increase of GeOxNy interlayer and the growth of unstable GeOx during subsequent processing.