中文摘要：

通过不同气体（NO、N2O、NH3）对Ge衬底进行表面预处理，生长GeOxNy界面层，然后采用反应磁控溅射方法生长HfTiO薄膜，制备HfTiO/GeOxNy叠层高k栅介质GeMOS电容，研究表面预处理对界面层以及界面层对器件性能的影响。隧穿电子扫描电镜（TEM）、栅电容-电压（C-V）栅极漏电流-电压（J-V）的测量结果表明，湿NO表面预处理能生长高质量的界面层，降低界面态密度，抑制MOS电容的栅极漏电流密度。施加高场应力后，湿NO表面预处理样品的平带漂移及漏电流增加最小，表示器件的可靠性得到有效增强。

英文摘要：

Novel surface pretreatments for preparing GeOxNy interlayer on Ge substrate by NO, N2O, NH3 gas, followed as depositing high-quality HfTiO gate dielectric by reactive co-sputtering method, and impacts of surface pretreatments on interlayer, and interlayer on electrical and reliability properties were investigated. The experimental results of TEM, C-V and J-V show that wet-NO pretreatment can effectively improve interface quality, and decrease gate leakage current of Ge MOS capacitors. Good reliability properties for wet-NO pretreatment sample with the smallest increase of leakage current and flat-band voltage after high- field stress are achieved.