Studies of thick films (approximately 30 μm) of undoped zinc oxide on sapphire substrate obtained by magnetron sputtering method with the use of an uncooled target were conducted. The structural and luminescent properties of the initial films and films that underwent additional recrystallization annealing in the air were investigated. The time and temperature dependent characteristics of the samples were considered. It was shown that annealing in air leads to an improvement in the structural, optical, and luminescent properties of the obtained film.

The results of comparative studies of the processes of high-temperature synthesis, luminescence and scintillation characteristics of ZnO films on M(100)- and A(110)-orientation sapphire substrates are presented. It is shown that the use of the magnetron deposition method makes it possible to form, against the background of a continuous film, ensembles of individual [001] ZnO microcrystals with pronounced X-ray luminescent properties. The X-ray luminescence kinetics is characterized by two components: a fast component with a decay time in the order of a nanosecond and a slow luminescence component. The study of the films by photoluminescence spectroscopy revealed the features of the near-band-edge luminescence spectra of the samples, in particular, the presence of various excitonic emission channels. Differences in the spectral parameters of the near-band-edge luminescence band in the case of optical and X-ray excitation are found and interpreted.

For the first time, the work presents a thin-film X-ray scintillator based on ZnO with a thickness of more than 100 μm with luminescence decay kinetics of the order of 1.1 ns (including the width of the exciting pulse). The absorption edge of the film scintillator is shown to be located in the region 388 nm. The total transmittance of the sample in the visible and near infrared region reaches 40%. The X-ray luminescence spectrum is represented by two intense bands: a narrow band of excitonic nature with a maximum in the region of 389 nm and a wide band of green luminescence related to intrinsic defects.