en گروه سرامیک Ceramic Materials and Engineering Research Paper Research Paper Abstract: A thermodynamic model was used to find out the optimum temperature for the growth of ZnS single crystals in closed ampoules by chemical vapor transport technique. Based on this model 1002 °C was found to be optimum temperature for 2 mg/cm3 concentration of transporting agent (iodine). ZnS Crystals were grown in optimum (1002 °C) and non-optimum (902 °C and 1102 °C) temperatures. The composition structure and microstructure of the grown crystals were studied by Atomic absorption spectroscopy, X-ray diffraction and Scanning electron microscopy measurements. Properties of the grown crystals were correlated to the growth conditions especially a stability in mass transport along the closed tube length. Keywords: Semiconductors, Crystal growth, Electron microscopy, X-ray diffraction, Microstructure. 51 61 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-127-6&slc_lang=en&sid=1 M. J. Tafreshi mj.tafreshi@gmail.com 180031947532846001464 180031947532846001464 Yes B. Dibaie 180031947532846001465 180031947532846001465 No M. Fazli 180031947532846001466 180031947532846001466 No