[23a-A202-1~10] 6.2 Carbon-based thin films

▼ [23a-A202-8] Ab-initio study of defects states in diamond/Al₂O₃ interface

〇YAOTANG ZHANG¹, NAOYA YAMAGUCHI², XUNFANG ZHANG², NORIO TOKUDA², FUMIYUKI ISHII² (1.Kanazawa Univ., 2.NanoMari.)

Keywords:diamond, power device

Since diamond has a series of excellent properties such as a wide band gap, high field strength, and high thermal breakdown conductivity, it has attracted much attention in the power-electronics field. Matsumoto et al. developed the inversion-channel diamond metal oxide semiconductor field-effect transistors (MOSFETs) where the diamond was OH-terminated and the oxide was Al₂O₃ formed by atomic layer deposition (ALD) [1]. Despite the normally off feature, the device suffered from low channel mobility. One main reason would be attributed to high density of interface states [2]. Prior to reducing interface states, it is significant to clarify their physical origin, which, however, has not been studied. In this work, we employed the first-principles calculations to reveal which factors are dominated and how they affect diamond/Al₂O₃ interface.