Yoshinobu Narita

Sciocs Company Limited
  • Fabrication of Recessed Structures for GaN HEMTs by a Simple Wet Etching Process

    Taketomo Sato, Hokkaido University
    Fumimasa Horikiri, Sciocs Company Limited
    Noboru Fukuhara, SCIOCS Company Ltd.
    Masachika Toguchi, Hokkaido University
    Kazuki Miwa, Hokkaido University
    Yoshinobu Narita, Sciocs Company Limited
    Osamu Ichikawa, SCIOCS Company Ltd.
    Ryota Isono, SCIOCS Company Ltd.
    Takeshi Tanaka, SCIOCS Company Ltd.

    Photoelectrochemical (PEC) etching is a promising technology for fabricating GaN devices with low damage. In the simple contactless PEC (CL–PEC) etching process that includes K2S2O8 in the electrolyte as an oxidizing agent, a sample is dipped into the electrolyte under UV irradiation. In this study, we applied CL–PEC to the gate-recess process of GaN HEMTs on an SiC substrate. The etching depth of the recess showed considerable reproducibility by the self-termination feature, and the residual AlGaN layer thickness was approximately 5 nm. The Schottky gate HEMTs with a recessed structure showed the normally off characteristics, and the Vth value was +0.4 V with a standard deviation of ±3.8 mV.

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  • 4.1 A Wafer-Level Uniformity Improvement by the Substrate Off Angle Control for the Vertical GaN-on-GaN Power Switching Devices

    Fumimasa Horikiri, Sciocs Company Limited
    Yoshinobu Narita, Sciocs Company Limited
    Takehiro Yoshida, Sciocs Company Limited
    Toshio Kitamura, Sciocs Company Limited
    Yukio Abe, Sciocs Company Limited
    Hiroshi Ohta, Osaka University
    Tohru Nakamura, Hosei University
    Tomoyoshi Mishima, Osaka University
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  • 7.2 An Analysis of the Surface Morphology of the GaN-on-GaN Epi Wafers and the Control by the Substrate Off Angle

    Fumimasa Horikiri, Sciocs Company Limited
    Yoshinobu Narita, Sciocs Company Limited
    Takehiro Yoshida, Sciocs Company Limited
    Chikashi Ito, KLA-Tencor Limited
    Varun Gupta, KLA-Tencor Limited
    Anoop Somanchi, KLA-Tencor Limited
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  • 10b.3 Mechanism of Initial Failures in Breakdown Voltage of GaN-on-GaN Power Switching p-n Diodes

    Fumimasa Horikiri, Sciocs Company Limited
    Yoshinobu Narita, Sciocs Company Limited
    Takehiro Yoshida, Sciocs Company Limited
    Hiroshi Ohta, Osaka University
    Tomoyoshi Mishima, Osaka University
    Tohru Nakamura, Hosei University
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