The complex surface morphology, defect subsystem and an ab initio model study of Pb1-xCdxTe thin films deposited on mica-muscovite substrates by PVD technology in open vacuum are presented in this paper. The thickness, growth mechanisms and uniformity of condensates, depending on deposition regimes, were studied by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The deposited films have a granular structure and sizes of crystallites depend on thickness and difference between substrate and condensate crystallographic parameters. The dominance of film growth by the Vollmer-Weber mechanism is demonstrated. Studies of film growth mechanisms have allowed us to predict that the formation of grains and the dynamics of their size changes during film growth are caused by complex defects associated with Cd atoms in nodes and vacancies of chalcogens.