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

In this study, high-performance In
₂
Se
₃
/Silicon-on-Insulator (SOI) heterojunction field-effect transistor photodetector is fabricated. The In
₂
Se
₃
/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
^-1/2
and higher detectivity of 2.9×10
¹³
cm.Hz
^1/2
W
^-1
. Flicker noise dominates the In
₂
Se
₃
/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.