Large scale plane-wave based density-functional theory simulations for electronic devices

In this paper, we demonstrate that it is practical to use plane-wave based density functional theory (DFT) calculations to study a wide range of problems related to electronic devices like field-effect transistor (FET). Realistic crystalline-Si and amorphous-SiO2 interface is constructed to model the device. A divide and conquer linear scaling three-dimensional fragment method (LS3DF) together with a special Poisson solution scheme is used to solve the whole device system self-consistently under nonequilibrium condition. A special fully ab initio quantum transport calculation method is developed to simulate the current flow through the device. We also show that the plane-wave DFT is capable of studying the reliability dynamics rooted in oxide/interfacial defects including the Si-H bond breaking due to electron excitation.