Self-powered photodetector based on direct vapour transfer (DVT) method grown tin selenide (SnSe) crystals

The 2D-TMDC (transition metal dichalcogenides) formed thin films have attracted more attention due to their tuneable optoelectronic properties that improved the application of the photo-sensing device. SnSe single crystals were grown in the current work utilising the direct vapour transfer (DVT) technique. The elemental proportion and 2D surface structural analysis of grown crystal SnSe are carried out using Energydispersive X-ray analysis (EDAX) and Scanning electron microscopy (SEM). The orthorhombic crystal system of grown SnSe confirmed by high resolution transmission electron microscopy (HRTEM), and Powder X-ray diffractometer (XRD), the regular spot patter of HRTEM and Sharp pick in XRD graph indicated that the SnSe are highly crystalline in nature. The X-ray photoelectron spectroscopy (XPS) is carried out for confirming the binding states and chemical composition of grown SnSe single crystal. The A1g, beta 3g and A2g vibration mode of SnSe single crystal confirmed using Raman Spectroscopy. In the application part, SnSe exhibits high photodetection capability under the monochromatic and polychromatic light sources at self-bias mode (photoresponsivity of 71.20 mu A/W and photo-detectivity of 3.45 x 108 Jones). The optoelectronic characteristics of SnSe devices including dependent photo-responses have also been carried out. Additionally, the important factors affecting photodetection characteristics are assessed, including photocurrent (Iph), sensitivity (S), photoresponsivity (R), Specific detectivity (D*), rise time, and decay time. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

In this study, SnSe single crystals were grown using the direct vapour transfer (DVT) technique. The elemental proportion and 2D surface structure of the grown crystals were analyzed using Energydispersive X-ray analysis (EDAX) and Scanning electron microscopy (SEM). The crystal system of SnSe was confirmed to be orthorhombic, and its high crystallinity was observed through high resolution transmission electron microscopy (HRTEM) and Powder X-ray diffractometer (XRD). The photodetection capability of SnSe was evaluated, showing high photoresponsivity and photo-detectivity under different light sources.