Thermally Grown MoSe2 Thin Film-Based n-MoSe2/p-Si Broadband Photodetector

This article reports an n-MoSe2/p-Si heterojunction-based broadband photodetector fabricated by depositing an n-MoSe2 thin film on a $\langle 100\rangle $ p-Silicon substrate (2– $5~\Omega $ -cm resistivity) by a thermal evaporation method. The facile hydrothermal route was adopted to synthesize MoSe2 powder. The as-synthesized MoSe2 powder was then deposited on the p-type Si substrate to form a p-n heterojunction. The photoresponse of the fabricated device was measured using monochromatic light of 300–1100 nm wavelengths. The maximum responsivity, detectivity, and external quantum efficiency (EQE) of the fabricated device were obtained as 316.25 mA/W, $1.54\times 10^{{11}}$ Jones, and ~45%, respectively, at 890 nm with the applied reverse bias voltage of 2 V. The rise time and fall time of the device was 396 and 224 ms, respectively.