Theoretical insights towards a highly responsive AgInSe₂ photodetector

This treatise showcases the design as well as modeling about a photodetector (PD) based on AgInSe 2 (AISe), a direct bandgap chalcopyrite with a bandgap of 1.19 eV. The PD exhibits outstanding optical and electronic characteristics, showcasing remarkable performance. The PD has been systematically investigated by varying the width, carrier density, and defect densities of specific layers, as well as the interface defect density of specific interfaces. Various layers are optimized to enhance the overall performance of the PD and the impact of different device resistances is analyzed. The photocurrent (J SC ) and voltage (V OC ) of the heterostructure photodetector are determined to be 38.60 mA/cm 2 and 1.0 V, in turn. The maximum responsivity ( R ) and detectivity ( D *) are identified as 0.70 A/W and 4.60 × 10 16 Jones, respectively at a wavelength of 940 nm. The spectral response exhibits significantly higher values in the range of 800–1000 nm, indicating the device's capability to detect near‐infrared (NIR) light. This research provides valuable insights for the manufacturing of AISe material‐based photodetectors with enhanced performance.