Computational design of functional nanoscale interface using first-principles calculation

基于密度泛函理论，开发了纳米结构中电子输运性质的计算方法和程序。利用新开发的程序从理论上研究了Si/SiO_2界面堆积结构缺陷的存在与泄漏电流的关系。我发现，通过有悬空键的界面的泄漏电流是没有任何缺陷时的530倍，预计会导致介质击穿。悬空键的方向与氧化物作为绝缘体的性能密切相关。此外，还证明了氢原子终止悬空键对减小漏电流是有效的。

The calculation method and code for electron-transport properties through nanostructures based on density functional theory have been developed. The relationship between the presence of defects at the stacking structure of the Si/SiO_2 interface and leakage current is theoretically studied using the newly developed code. I found that the leakage current through the interface with dangling bonds is 530 times larger than that without any defects, which is expected to lead to dielectric breakdown. The direction of the dangling bonds is closely related to the performance of the oxide as an insulator. In addition, it is proved that the termination of the dangling bonds by hydrogen atoms is effective for reducing the leakage current.