Characterization of Nanocrystalline SnS Thin Film Fabricated used PLD Method for Photodetection Applications

Abstract

Pulsed laser deposition was used to create tin sulfide (SnS) nanoparticles with a Nd:YAG laser (700 mJ) with laser pulses of (200, 250, 300, and 350 pulses). Nanoparticles were created and investigated using XRD, AFM, and UV-Vis spectroscopy to understand their optical, topographical, and electrical properties. After that, a SnS photodetector was built for the first time, and its performance, photoresponse, and sensitivity were evaluated. The development of monocrystalline SnS films was confirmed by X-ray diffraction (XRD) examination. Clear crystallization with increased crystalline size and the optimum orientation was observed in the sample synthesized SnS thin film treated with 300 pulses. The crystallite size increased from 44 at 200 to 77 nm for 350 pulses. These films were characterized by better surface morphology with (111) preferred crystals. In addition, atomic force microscopy (AFM) studies showed that the average diameter of generated SnS nanoparticles rose from (39.4 nm to 64.7) nm when the laser pulses increased in pulsed laser deposition. Transmission measurements were used to determine the films' absorption coefficient energy gap (Eg), and they showed that the optical transition was direct and that the transmittance value dropped with increasing laser pulses. Band gap energy is reduced from 2.139 to 1.773 eV. Moreover, Hall Effect measurements on all samples demonstrate that all thin films were n-type, with charge carrier concentration increasing with increased pulses and carrier mobility decreasing with increased pulses. The photodetectors ' photosensitivity was evaluated in the dark after depositing Al contacts on SnS thin films through a metal mask. The Pulses of enhancement cause a red shift in the values of particular detectivity and quantum efficiency. The highest responsivity was obtained at 350 pulses, 6.72×10−1 AW−1. The high (QE) of 150% at 200 p and detectivity of 2.9×1011 cm, Hz1/2.W-1 at 300p.