The photovoltaic and photoconductive photodetector based on GeSe/2D semiconductor van der Waals heterostructure

Abstract

Although plenty of two-dimensional (2D) semiconductor heterostructure photodetectors have been studied, there is still a lack of systematic comparison and analysis about photovoltaic and photoconductive 2D semiconductor photodetectors. Taking advantage of the 2D semiconductor van der Waals heterostructure, this work constructs a photovoltaic (PV) GeSe/MoS2 and a photoconductive (PC) GeSe/graphene photodetector, respectively. The PC GeSe/graphene photodetector achieves relatively higher photoresponsivity (R), where R can reach up to 104 AW−1. The PV GeSe/MoS2 photodetector, by contrast, obtains a faster photoresponse speed. More importantly, the photoresponse properties of the PV GeSe/MoS2 photodetector can remain constant under the reverse bias, due to the minority carrier conduction in its depletion region at this time. The different characteristics of the two type 2D photodetectors are explored in detail, which can play a guiding role in the construction of high-performance photodetectors.

A review of molybdenum disulfide (MoS2) based photodetectors: from ultra-broadband, self-powered to flexible devices

“…422 The photodetector also exhibited bidirectional photocurrent response associated with type-II band aligned heterostructure and ITO electrodes. Yang et al 423 used narrow bandgap layered semiconductor germanium selenide (GeSe) for developing hybrid photodetectors where photoconductive GeSe/graphene photodetectors were compared with photovoltaic GeSe/MoS 2 photodetectors. The photodetector based GeSe/graphene vdWHs showed higher photoresponsivity up to 10 4 A W À1 under laser light intensity of 0.17 mW cm À2 at 532 nm whereas the GeSe/MoS 2 heterostructure based photodetector exhibited low photoresponsivity of 0.1 A W À1 but a faster recovery time of 5 ms compared with 2 s for GeSe/graphene heterostructure.…”

An InGaN/SiNx/Si Uniband Diode Photodetector

“…In contrast, the band offsets for 2D materials can freely adjust due to the van der Waals bonds at the interfaces. [15,[26][27][28][29] Under illumination, the I-V curves with logarithmic current scale for the InGaN/SiN x /Si uniband diode PD are shown in Figure 3a for different wavelengths of the incident light: 808, 638, 532, and 405 nm and 10 mW cm À2 excitation power density. The I-V curves with reduced linear scales around zero are shown in the inset.…”

“…In contrast, the band offsets for 2D materials can freely adjust due to the van der Waals bonds at the interfaces. [ 15,26–29 ]…”

Photovoltaic Field-Effect Photodiodes Based on Double van der Waals Heterojunctions

“…However, for HBD, shown in Figure e, the η can be calculated about 0.61%, which is far below that of PVFED. Similar to other HBD structures, no photovoltaic behaviors or weak photovoltaic performance were observed. ,, In order to further identify the role of the bottom vdWH on modulating the performance of PVFED, the comparative study of PVFED and pn juncton diode performance was also performed, shown in Figure S6. The PVFED exhibits the low dark current (0.71 pA) and the high light-to-dark ratio (7.7 × 10 4 ) at zero bias.…”