RF performance of high transconductance and high-channel-mobility surface-channel polycrystalline diamond metal-insulator-semiconductor field-effect transistors

Hitoshi Umezawa, Takuya Arima, Naoki Fujihara, Hirotada Taniuchi, Hiroaki Ishizaka, Minoru Tachiki, Christoph Wild, Peter Koidl, Hiroshi Kawarada

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The RF device potential of surface-channel polycrystalline diamond metal-insulator-semiconductor field-effect transistors (MISFETs) is demonstrated for the first time. Utilizing a self-aligned gate field-effect transistor (FET) fabrication process, effective transconductance of 70 mS/mm is realized at 0.7 μm gate length. This FET also shows high fTT and fmax of 2.7 and 3.8 GHz, respectively. However, the breakdown voltage and f max/fT ratio are lower than those for the homoepitaxial layer because of the parasitic capacitance at the grain boundaries in the drain region. Because of the fluctuation of channel mobility, the fluctuation of gm and fT is observed. In order to realize high-power operation at high frequency, the fabrication of the FET on a single grain to reduce the parasitic capacitance is required.

Original languageEnglish
Pages (from-to)2611-2614
Number of pages4
JournalJapanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers
Issue number4 B
Publication statusPublished - 2002 Apr 1



  • Hydrogen-terminated surface channel
  • Polycrystalline diamond
  • RF performance
  • Self-aligned gate process

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

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