表面合金化对NiPt金属栅电极功函数的影响Effect of Surface Alloying on Work Function of NiPt Metal Gate
许桂贵;吴景;黄志高;
摘要(Abstract)：
利用基于密度泛函理论的第一性原理方法研究了Ni1-xPtx(111)和Ni1-xPtx(001)表面合金的功函数.计算结果表明,Pt原子掺杂在表面层时对功函数影响较大,而且表面层Pt原子掺杂后的合金结构最为稳定;对于Ni1-xPtx(001),当表面层Pt原子的覆盖度从0增加到100%时,功函数近线性增加了0.6eV;而对于Ni1-xPtx(111),当表面层Pt原子的覆盖度从0增加到25%时,功函数增加了0.22eV,覆盖度从25%增加到100%时,功函数却几乎不再变化.上述结果表明,表面层合金化对功函数有重要影响,而金属功函数又强烈依赖于表面取向.
关键词(KeyWords)： 表面合金化;NiPt;第一性原理;功函数
基金项目(Foundation): 国家自然科学基金资助项目(11074039;11004032)
作者(Authors): 许桂贵;吴景;黄志高;
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