Cryogenic operation of surface-channel diamond field-effect transistors

Hiroaki Ishizaka, Minoru Tachiki, Kwang Soup Song, Hitoshi Umezawa, Hiroshi Kawarada

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    6 Citations (Scopus)


    Cryogenic operation of field-effect transistors (FETs) fabricated on hydrogen-terminated (H-terminated) diamond surface conductive layers is investigated. 5-μm gate-length metal-insulator- semiconductor FETs (MISFETs) is fabricated using CaF2 film as a gate insulator. The MISFETs operate successfully even at 4.4 K. At low temperature, the contact between source/drain electrode and H-terminated diamond surface cannot maintain ohmic characteristics, because the thermal activation energy of the carriers is not high enough to overcome the barrier height at the interfaces between the source electrode and the H-terminated diamond. Estimated channel mobility increases from 63 cm2/V-s to 137 cm2/V-s and the maximum transconductance increases from 10.5 mS/mm to 14.5 mS/mm, as the temperature decreases from 300 K to 4.4 K, indicating reduced phonon scattering of the channel.

    Original languageEnglish
    Pages (from-to)1800-1803
    Number of pages4
    JournalDiamond and Related Materials
    Issue number10-11
    Publication statusPublished - 2003 Oct



    • Cryogenic temperature
    • Hydrogen-terminated diamond
    • MISFET

    ASJC Scopus subject areas

    • Electronic, Optical and Magnetic Materials
    • Materials Chemistry
    • Surfaces, Coatings and Films
    • Surfaces and Interfaces

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