Open AccessInversion channel diamond metal-oxide-semiconductor field-effect transistor with normally off characteristics
Author(s) -
Tetsuya Matsumoto,
Hiromitsu Kato,
Kazuhiro Oyama,
Toshiharu Makino,
Masahiko Ogura,
Daisuke Takeuchi,
Takao Inokuma,
Norio Tokuda,
Satoshi Yamasaki
Publication year - 2016
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep31585
Subject(s) - diamond , materials science , optoelectronics , mosfet , field effect transistor , gate oxide , transistor , annealing (glass) , silicon , electrical engineering , voltage , composite material , engineering
We fabricated inversion channel diamond metal-oxide-semiconductor field-effect transistors (MOSFETs) with normally off characteristics. At present, Si MOSFETs and insulated gate bipolar transistors (IGBTs) with inversion channels are widely used because of their high controllability of electric power and high tolerance. Although a diamond semiconductor is considered to be a material with a strong potential for application in next-generation power devices, diamond MOSFETs with an inversion channel have not yet been reported. We precisely controlled the MOS interface for diamond by wet annealing and fabricated p-channel and planar-type MOSFETs with phosphorus-doped n-type body on diamond (111) substrate. The gate oxide of Al 2 O 3 was deposited onto the n-type diamond body by atomic layer deposition at 300 °C. The drain current was controlled by the negative gate voltage, indicating that an inversion channel with a p-type character was formed at a high-quality n-type diamond body/Al 2 O 3 interface. The maximum drain current density and the field-effect mobility of a diamond MOSFET with a gate electrode length of 5 μm were 1.6 mA/mm and 8.0 cm 2 /Vs, respectively, at room temperature.