16:00 〜 18:00
[18p-PB3-43] グラフェン-Ga2O3ヘテロ構造によるショットキー接合の作製とソーラーブラインドフォトダイオードへの応用
キーワード:グラフェン、酸化ガリウム
Ultraviolet (UV) photodetectors are key component for various applications in the field of environmental monitoring, flame detection, astronomical studies, digital imaging, short-wave communication and other emerging technologies such as internet-of-things (IoT) sensors. Among, various oxide semiconductors monoclinic beta-gallium oxide (β-Ga2O3) with a direct band gap of 4.5-4.9 eV can be suitable for solar-blind UV photodiode applications. Here, we demonstrate formation of a suitable Schottky barrier potential in graphene/β-Ga2O3 heterojunction enabling fabrication of a deep-UV photodiode. A photovoltaic action was obtained with an open circuit voltage (Voc) of 10 mV and short circuit current density of 4.4 (Jsc) µA/cm2 for DUV irradiation, attributing to possible self-powered operation of the photodiode. We also observed a bias dependent transient photoresponse for the fabricated device. A faster photoresponse was obtained for self-powered mode of the solar-blind photodiode.