Surface Defects and Passivation of Ge and III-V Interfaces

The need for high-kappa gate dielectrics and metal gates in advanced integrated circuits has reopened the door to Ge and III-V compounds as potential replacements for silicon channels, offering the possibility to further increase the performances of complementary metal oxide semiconductor (CMOS) circuits, as well as adding new functionalities. Yet, a fundamental issue related to high-mobility channels in CMOS circuits is the electrical passivation of their interfaces (i.e., achieving a low density of interface defects) approaching state-of-the-art Si-based devices. Here we discuss promising approaches for the passivation of Ge and III-V compounds and highlight insights obtained by combining experimental characterization techniques with first-principles simulations.