Effective work function of metals interfaced with dielectrics: A first-principles study of the Pt-HfO2interface
Effective work function of metals interfaced with dielectrics: A first-principles study of the Pt-HfO2interface
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DOI：
10.1103/physrevb.83.081416
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发表时间：
2011-02
影响因子：
3.7
通讯作者：
H. Zhu;R. Ramprasad
中科院分区：
文献类型：
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作者：
H. Zhu;R. Ramprasad
提出了一种确定有效功函数的无参数方法，该功函数定义为金属在金属-介质界面电介质侧的功函数。这种方法依赖于通过标准密度泛函理论计算的界面偶极矩直接确定有效功函数，而不需要标度带隙和带偏移。对于铂-HfO2界面的情况，这一策略与统计热力学原理相结合来预测在给定的温度和O2压力组合下最可能的有效功函数(通过确定最有利的界面O覆盖率)。预测结果与观测结果吻合较好。
A parameter-free methodology to determine the effective work function, defined as the work function of the metal on the dielectric side of a metal-dielectric interface, is presented. This method relies on the direct determination of the effective work function through the interfacial dipole moment from standard density functional theory calculations devoid of scaling the band gap and band offset. For the case of a Pt-HfO2 interface, this strategy is combined with statistical thermodynamic principles to predict the most probable effective work function at given combinations of temperature and O2 pressure (through determination of the most favored interfacial O coverage). The predicted results are in excellent agreement with observations.