High broadband photoconductivity of few-layered MoS₂field-effect transistors measured using multi-terminal methods: effects of contact resistance

Abstract

Among the layered two dimensional semiconductors, molybdenum disulfide (MoS2) is considered to be an excellent candidate for applications in optoelectronics and integrated circuits due to the layer-dependent tunable bandgap in...

Vinyl-Flanked Diketopyrrolopyrrole Polymer/MoS2 Hybrid for Donor–Acceptor Semiconductor Photodetection

“…36 In our previous report, a similar wavelength-dependent photoresponsivity was reported where responsivity decreased rapidly from 800 to 900 nm and no responsivity was measured above 900 nm due to the limitation of band edge absorption of the MoS 2 . 40 Remarkably, our PDPPVTT/MoS 2 hybrid system recorded a stable high photoresponsivity of R ∼100 A/W in the range of 900−1050 nm. This photoresponsivity above 900 nm wavelength is attributed to the absorption of the NIR absorbing PDPPVTT where MoS 2 abosrption is extremely low.…”

“…This result suggests that our CVT-grown MoS 2 is electron-doped. 40 The mobility was extracted using the MOSFET formula given below (eq 4)…”

“…This value is similar to the previously reported mobility from our two-terminal measurements. 40 The mobility is also limited by the contact resistance associated with the two-terminal measurements and can be improved using the four-terminal method. 40,60,61 After the initial FET characterization on the device, we explored the photoresponse of the MoS 2 device under white light illumination of power, P opt = 0.9 nW, by measuring I ds vs V ds , I ds vs V bg , and extract the photocurrent I ph vs V ds (Figure 7a,b,e).…”

“…40 The mobility is also limited by the contact resistance associated with the two-terminal measurements and can be improved using the four-terminal method. 40,60,61 After the initial FET characterization on the device, we explored the photoresponse of the MoS 2 device under white light illumination of power, P opt = 0.9 nW, by measuring I ds vs V ds , I ds vs V bg , and extract the photocurrent I ph vs V ds (Figure 7a,b,e). The device yields much higher current under white light illumination of 0.9 nW incident power than under dark conditions (without light) as shown in Figure 7a,b.…”

An In Situ Reflectance Spectroscopic Investigation to Monitor Two-Dimensional MoS2 Flakes on a Sapphire Substrate

“…The monolayer MoS 2 has a direct band-gap, which is between graphene with zero band-gap and hexagonal boron nitride with wide band-gap. It is considered to have attractive prospects for sensors, catalysis, supercapacitor, and optoelectronic devices [5][6][7][8][9][10][11]. It is crucial to acquire high-quality materials for industrial applications.…”