[14p-B401-1~17] 13.7 Compound and power electron devices and process technology

△ [14p-B401-16] Reduction of contact resistance of ALD-Al₂O₃ diamond MOSFETs by selective regrowth high concentration boron doped layer;Drain current density | I_DS | > 1 A/mm

〇(B)Yukiko Suzuki¹, Shoichiro Imanishi¹, Ken Kudara¹, Kiyotaka Horikawa¹, Shotaro Amano¹, Masayuki Iwataki¹, Aoi Morishita¹, Atsushi Hiraiwa¹, Hiroshi Kawarada^1,2 (1.Waseda Univ., 2.Zaiken.)

Keywords:diamond, MOSFET, radio frequency

To improve the high-frequency output power density P_out of FET, it is effective to improve the maximum drain current density I_DSmax. For the conventional two-dimensional hole gas (2DHG) diamond MOSFETs using TiC as source and drain electrodes, the on-resistance of 30 Ω mm and the contact resistance of 9 Ω mm brought about the high knee voltage and the low I_DSmax. For a high-frequency device of the miniaturized distance between the source and drain electrodes, the ratio of contact resistance to on-resistance is high. Thus low R_C can further enhance RF output power density. In this study, heavily boron-doped growth layer was introduced directly under the source-drain electrodes of 2DHG diamond MOSFETs to reduce R_C, and R_C = 1.1 Ω mm and | I_DSmax |> 1 A / mm were obtained.