Investigation of annealing temperature effect on magnetron sputtered cadmium sulfide thin film properties

Abstract

Cadmium sulfide (CdS) thin films are deposited on the fluorine doped tin oxide coated glass substrate using the radio frequency magnetron sputtering setup. The effects of annealing in air on the structural, morphological, and optical properties of CdS thin film are studied. Optimal annealing temperature is investigated by annealing the CdS thin film at different annealing temperatures of 300, 400, and 500°C. Thin films of CdS are characterized by X-ray diffractometer analysis, field emission scanning electron microscopy, atomic force microscopy, UV-Vis-NIR spectrophotometer and four point probe. The as-grown CdS films are found to be polycrystalline in nature with a mixture of cubic and hexagonal phases. By increasing the annealing temperature to 500°C, CdS film showed cubic phase, indicating the phase transition of CdS. It is found from physical characterizations that the heat treatment in air increased the mean grain size, the transmission, and the surface roughness of the CdS thin film, which are desired to the application in solar cells as a window layer material.

Xrd, Optical and Vibrational Properties of Annealed Cadmium Sulfide Films

“…It also can be seen in these Figure, the optical band gap changes from 2.40 eV to 2.44 eV with an annealing temperature going up from 200°C to 500°C. The optical band gap values of CdS films are in accordance with the literature data [5,8,13,15,24,25]. These values of the optical band gap may be suggested as being suitable as a window layer fabrication for thin film solar cells.…”

“…The surface roughness of cadmium sulfide films increase with the increasing of the annealing temperature. These might happen because of the differences in crystallite size of the CdS films [5,15,26]. From optical microscope images, the color of the film was found to change from an orange and greenish yellow to pale green and finally to greenish yellow with the rising of the annealing temperature [27,28].…”

“…The structure of the CdS films can be changed by either preparation condition or preparation method. The annealing temperature (Ta) is one of the most important parameters which affect the physical properties of thin films such as the structural, vibrational and optical properties [14,15]. Chander and Dhaka [16], by using Electron Beam Vacuum Evaporation Method to obtain CdZnTe thin film, demonstrated that optical absorption is increased with increasing annealing temperature, resulting in decrease in optical energy gap.…”

Annealing and plasma treatment effect on structural, morphological and topographical properties of evaporated β-In2S3 films

“…It can be observed that the surface of the films was covered with uniformly distributed grains that had different shapes without any cracks. In case of untreated films, the grain size was increased for films annealed at 200°C and 250°C due to the coalescence of smaller grains [33,34]. In contrary, the appearance of nanoparticle ensembles isolated from each other on the surface became typical after plasma treatment.…”

Effect of Rotational Speed on Linear and Non-Linear Optical Properties of Sol-Gel Spin Coated Nanostructured CdS Thin Films

“…The average roughness (Ra) of the CdS thin films increased from 8.9 to 23.4 nm, whereas the RMS roughness (Rq) values increased from 6.6 to 18.5 nm with the increase of rotational speed from 1500 to 3000 rpm. The increase in surface roughness of the films decreases the reflective loss which consequently increases the quantum efficiency of a solar cell [18]. The maximum peak height (Rp) and peak valley (Rz) values increased with the increase of rotational speed due to the improvement in crystallinity of the films.…”