Fabrication of ᵞ-In₂Se₃-Based Photodetector Using RF Magnetron Sputtering and Investigations of Its Temperature-Dependent Properties
Yogesh Hase, Vidhika Sharma, Mohit Prasad, Rahul Aher, Shruti Shah, Vidya Doiphode, Ashish Waghmare, Ashvini Punde, Pratibha Shinde, Swati Rahane, Bharat Bade, Somnath Ladhane, Habib M. Pathan, Shashikant P. Patole, Sandesh Jadkar
Abstract
Metal chalcogenide indium selenide (In2Se3) is attracting increasing research interest for photodetector applications due to its excellent photoresponse and superior stability under ambient conditions. However, the temperature-dependent performance of In2Se3-based photodetectors has rarely been reported. Here, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -In2Se3 thin films were prepared at various deposition pressures using the RF magnetron sputtering for photodetector applications. The formation of single-phase <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -In2Se3 films has been confirmed by the X-ray diffraction (XRD) and Raman analyses. Binding energies and elemental composition of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -In2Se3 films were examined by XPS analysis. Field emission scanning electron microscopy (FE-SEM) images show that the prepared <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -In2Se3 films were crack- and pore-free, dense, compact, smooth, and have small grains. The optical energy bandgap decreases from 2.2 to 1.7 eV with an increase in deposition pressure. Then, the photoresponse of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -In2Se3-based photodetectors was investigated. The photodetector fabricated with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -In2Se3 at 5 Pa on an ITO-coated interdigital electrode (IDE) exhibited excellent photoresponsivity ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.82~\mu \text{A}$ </tex-math></inline-formula> /W) and detectivity ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$7.06\times 10^{{7}}$ </tex-math></inline-formula> Jones) with a fast rise time of 0.26 s and a decay time of 0.32 s. Finally, the temperature-dependent photoresponse of the photodetector fabricated with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula> -In2Se3 at 5 Pa is meticulously investigated. We found that the photodetector properties of a photodetector critically depend on the operating temperature.