Deposition and characterization of ZnxMg1−xS thin films on amorphous substrates

ZnxMg1−xS thin films are deposited on the ‘amorphous’ glass substrate in the whole composition range. The crystal structure of ZnxMg1−xS solid solutions has been determined from the results of film composition and from their structural and optical characteristics. It has been found that for 0.14 < x ≤ 1, ZnxMg1−xS with a zincblende structure is formed whereas for 0 ≤ x < 0.07, Mg-rich ZnxMg1−xS with a rocksalt structure is formed. In the intermediate range of 0.07 ≤ x ≤ 0.14, the miscibility gap has been found to exist. The miscibility behaviour is discussed on the basis of the ionicity fraction fi for ZnS and MgS.