Surface morphology and depth profile study of Cd1−xZnxTe alloy nanostructures

• Published in: Journal of alloys and compounds 2012-12, Vol.545, p.90-98
• Main Authors: Yilmaz, Ercan, Tuğay, Evrin, Aktağ, Aliekber, Yildiz, Ilker, Parlak, Mehmet, Turan, Raşit
• Format: Article
• Language: English
• Subjects: AFM; Annealing; CdZnTe; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deposition; Deposition by sputtering; EDS; Exact sciences and technology; Heat treatment; Ii-vi semiconductors; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Nanomaterials; Nanostructure; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of specific thin films; Physics; SEM; Spectroscopy; Sputtering; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Thin films; X-ray photoelectron spectroscopy; XPS; XRD
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2012.08.028

► Cd1−xZnxTe (CZT) films were grown on heated glass at 400°C from a single target. ► CZT films were annealed at 300 and 450°C for 1h under N2 gas at atm. pressure. ► The structural and optical properties of CZT films were studied. ► Better structural stability and reproducibility in CZT films were succeeded. ► Uniform and stoichiometric CZT films with required compositions were fabricated. Cd1−xZnxTe thin films with thickness of 200nm were deposited on glass substrates from a single sputtering target. During the deposition process, the substrates were heated at 400°C and deposited films were subjected to an annealing process at 300 and 450°C for an hour under flowing N2 gas at atmospheric pressure. Influence of in situ heating and post-deposition annealing treatments on the structural and optical evolution of Cd1−xZnxTe nanostructures were investigated by diagnostic techniques such as X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and UV-transmission spectroscopy. The transmission spectra in the region of the optical absorption band edge were measured for as-deposited and heat-treated of CdZnTe samples. Band gap of the deposited films were found to be in the range of 1.59–1.66eV. The XRD studies revealed that heated Cd1−xZnxTe films have a cubic oriented (111), (220) and (311) polycrystalline structure whereas unheated films are mostly amorphous. The effects of annealing temperature on the composition of the thin films were discussed. XPS measurements were performed in the depth profiling mode in order to understand the variation in the chemical composition of the films. Results were compared with the structural analysis obtained from the XRD measurements.