Large area, low power MoSe2 nanostructures based Infrared photodetectors on flexible substrates beyond $2.3\ \mu\mathrm{m}$

Abstract

A scalable, SWIR, MSM photodetector using MoSe2 flower-like nanostructures on a flexible substrate has been reported here. Films of MoSe2 have been synthesized in large areas using low-cost hydrothermal and drop-cast method. The MoSe2 nanostructures MSM detector shows photoresponse in the wide infrared range (1000-2400 nm) with a maximum photoresponse of ∼ 2.75 A/W at 2000 nm in the SWIR spectra. The synthesis process results in an imperfect growth of the MoSe2 nanostructures, which leads to defects in the lattice. These defects caused high SWIR optical absorption beyond its normal range. Under applied stress, change in photoresponse has been observed in the device due to the piezo-photonic effect in MoSe2 and barrier height modulation at the MoSe2-metal interface. This work demonstrates the potential of a low-cost fabrication scheme of large area TMDCs semiconductors to meet the increasing demands for wearable and portable electronics.