Structural and wavelength dependent optical study of thermally evaporated Cu₂Se thin films

Abstract

The present work encloses structural and optical characterization of copper (I) selenide (Cu2Se) thin films. The films having thickness 85 nm have been deposited using thermal evaporation technique in initial step of work. The structural and morphological studies of deposited thin films are then done by X-ray diffraction (XRD), scanning electron microscope (SEM), and surface profilometer measurements. Later on, ultraviolet-visible-near-infrared (UV-VIS-NIR) spectrophotometer and Raman spectroscopic measurements are performed for optical characterization of films. The structure and morphology measurements reveal that deposited material of films is crystalline. The optical band gap estimated from the optical transmission spectra of the film has been found 1.90 eV. The mean values of refractive index, extinction coefficient, real and imaginary dielectric constant are received 3.035, 0.594, 9.623, and 3.598, respectively. The obtained results are compared and analyzed for justification and application of Cu2Se thin films.

Study of the structural and optical properties of thallium gallium disulfide (TlGaS2) thin films grown via thermal evaporation

“…However, the nanoparticle sizes vary between 100 and 200 nm. Similar uniform nanoparticle deposition over the film surface was observed for Fe 2 O 3 [20], Cu 2 Se [21] and TiO 2 thin films [22]. The nanoparticle size distribution in the films can be improved by annealing them at high temperatures for longer periods.…”

All-Vacuum-Deposited Bifacial Cu2ZnSnSe4 Photovoltaic Cells with Sputtered Cd-Free Buffer Layer

“…The variation in reflectance was primarily attributed to the effects of material properties and surface topography, whereas the change in the reflectance of the films was primarily attributed to the refractive index of the materials and the roughness of the surface. Hirate et al and Yadav et al revealed that below 1200 nm, the trends of the change in the refractive index of CZTSe, Cu x Se, and CTSe are virtually the same [39,40]. Thus, little change occurred in the reflectance characteristics of the four samples.…”

Facile synthesis and characterization of Cu2Se thin films and self-powered p-Cu2Se/n-Si heterojunction with high-performance photoresponse

“…The PCE of the Cu 2 Se/Si solar cell presented here surpasses these reported values for the solar cells based on CuO/Si or Cu 2 O/Si systems. Yadav et al [56] reported that the refractive index n and the extinction coefficient K for Cu 2 Se in the visible light region (390-780 nm) range from 4.62 to 2.63 and from 0.569 to 0.613, respectively. Consequently, the reflectance R = [(n−1) 2 + K 2 ]/[(n + 1) 2 + K 2 ] for the Cu 2 Se film lies between 42% and 22%.…”