Exploring the structural, optical, and optoelectrical characteristics of p-type CuNiBiS3 thin films prepared by the chemical deposition method

The authors use chemical bath deposition to synthesize novel copper-nickel bismuth sulfide (CuNiBiS3) thin films on glass slides. The X-ray diffraction measurements detected the crystal structure of the CuNiBiS3 layers, which display orthorhombic structures for these films. The structural indices of the CuNiBiS3 layers were determined by the Williamson-Hall relationship. Furthermore, the Energy dispersive spectroscopy of the CuNiBiS3 layers refers to these layers having a stoichiometric composition. On the other side, the linear optical indices of the CuNiBiS3 layers were determined depending on the transmittance and reflectance data. The energy gap analysis indicates that the CuNiBiS3 layers have a direct optical transition. The energy gap values of the CuNiBiS3 layers were reduced from 1.43 to 1.31 eV by enlarging the thickness of these layers. These layers' nonlinear, optoelectrical, and dispersion indices, like the static high-frequency dielectric constant, optical conductivity, dispersion energy, nonlinear refractive index, and optical carrier concentration, were improved by boosting the layer thickness. Moreover, the hot probe test revealed that CuNiBiS3 layers tended to acquire p-type characteristics.