[11p-Z04-1~14] 13.7 Compound and power electron devices and process technology

▼ [11p-Z04-10] The Si-terminated 2DHG Diamond MOSFETs with the Normally-off operation and Wide Temperature Range Stability

〇(D)Te Bi¹, Wenxi Fei¹, Masayuki Iwataki¹, Aoi Morishita¹, Atsushi Hiraiwa¹, Hiroshi Kawarada^1,2 (1.Waseda Univ., 2.Kagami Memorial Research Inst. for Materials Science and Tech.)

Keywords:Diamond, Wide-bandgap semiconductor materials, Power device

Diamond exhibits excellent electrical properties such as high thermal conductivity about 22 kW m^-1K^-1, high breakdown field over 10⁷ V/cm, and high bulk hole mobility of 2000 cm² Vs^-1. We have developed the H-terminated (C-H) diamond MOSFETs by using the two-dimensional hole gas (2DHG) .On the other hand, the electronegativity of Si is 0.7 Pauling unit lower than that of C, the different electronegativity (C: 2.5, Si: 1.8) C-Si dipole could more holes accumulate on the silicon termination diamond than the C-H(C: 2.5, H: 2.1) , the spontaneous polarization of C-Si dipole expects to induce the 2DHG which can used as the p-channel to fabricate the MOSFETs, and the SiO₂ also is advantageous for power devices in terms of chemical stability and wide band gap. The SiO₂ can be used as the gate insulator in the diamond power devices. In this work, Si-terminated (C-Si) diamond MOSFETs has been fabricated with the boron-doped p+ diamond selective growth by using the SiO₂ as the mask for source and drain formation and the gate insulator and the C-Si diamond MOSFET achieved Normally-off operations and wide temperature range stability.