Synthesize and Investigate Structural, Surface Morphology, Optical, and Electrical Characterization of Cu₂Se Thin Films by Thermal Evaporation Technique

Copper selenide (Cu₂Se) is a promising semiconductor with notable potential for optoelectronic and thermoelectric applications. This study investigates the impact of film thickness on the physical properties of Cu₂Se thin films. Cu₂Se thin films of varying thicknesses were synthesized using the thermal evaporation technique. These films were then analyzed for optical properties, structural characteristics, and surface morphology. Optical analysis was conducted using absorption spectra over a wavelength range of 200 to 900 nm. From these spectra, we determined key optical parameters such as the energy band gap (E_g), extinction coefficient (k), and refractive index for films of different thicknesses. Dielectric properties were evaluated, allowing us to calculate the dielectric constant and dielectric loss for various film thicknesses. Additionally, current–voltage (I-V) characteristics and Raman spectroscopy were performed, and the results are presented and discussed in detail.