Comprehensive study of physical properties of cadmium telluride thin films: effect of post-deposition high annealing temperature

Abstract

Thin films of cadmium telluride (CdTe) with a thickness of 550 nm were prepared using the thermal evaporation method. The resulting films were annealed in air atmosphere at 200 °C, 300 °C, 400 °C and 500 °C. The annealed films were subjected to x-ray diffraction (XRD), micro-Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), ultraviolet-visible spectroscopy and transverse current–voltage (I–V) test analyses to investigate the structural, surface morphological, optical and electrical properties of films, respectively. The XRD patterns reveal the zinc blende structure of the pristine and treated film with the preferred (111) orientation. In addition, the crystallite size increases with the rise in annealing temperature. The Raman spectra reveal a redshift with annealing as well as the formation of Te precipitates in CdTe films. The SEM images show the uniformity and homogeneity of the as-prepared films. The AFM studies show an increase in the surface roughness of the annealed films. The optical energy band gap is found to decrease with the annealing temperature. The I–V measurement indicates the ohmic behavior of CdTe films. The experimental results indicate that the annealed CdTe thin films at 400 °C have optimized physical properties for solar cell applications as an absorber layer.

Impact of CdSeTe and CdSe film deposition parameter on the properties of CdSeTe/CdTe absorber structure for solar cell applications

“…Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. solar cells due to its favorable optical properties and ease of manufacturing [1,2]. Maturity of this solar cell technology is demonstrated by a cell efficiency of 22.1% and a photovoltaic (PV) module production volume of around 8 GW by the end of 2021 [3,4].…”

Effect of substrate type on the physical properties of thermally evaporated CdS thin films for CdTe/CdS solar cells applications

“…CdS thin films are fabricated on transparent glass substrates using a variety of growth methods like thermal evaporation (TE) [20], pulsed laser [21], close-spaced sublimation [22], electron beam evaporation [23], sputtering [24], spin coating [25], molecular beam epitaxy [26], atomic layer deposition [27], etc TE deposition is a promising technique of nanoparticle deposition on the substrates for fabricating high-quality thin films due to the low cost, a high deposition rate with the low tendency of oxidation and impurity formation in the prepared layer, as well as propagation of nanoparticles vapors on the direct-line toward the substrate [28,29].…”