In₂Se₃/Silicon-on-Insulator Heterojunction Phototransistor for Low Noise Dual-Band Detection

Abstract

In this study, high-performance In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Se <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> /Silicon-on-Insulator (SOI) heterojunction field-effect transistor photodetector is fabricated. The In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Se <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> /Si heterostructure phototransistor exhibits dual-band detection with a maximum responsivity of 12 A/W and 41 A/W for illumination of 405 nm and 800 nm wavelengths, respectively. This phototransistor has shown a lower noise-equivalent power of 6.8 fW.Hz <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1/2</sup> and higher detectivity of 2.9×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">13</sup> cm.Hz <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1/2</sup> W <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> . Flicker noise dominates the In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Se <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> /SOI phototransistor with a corner frequency of 3 Hz. The device's enhanced performance is due to the improved synergistic effect with efficient electron-hole dissociation in the heterojunction. This heterostructure based photodetector can be of great interest for dual-band (Ultra-violet and visible) detection in imaging, optical communication and healthcare applications.