Особенности интерпретации спектров люминесценции пленок оксида цинка на сапфире

Abstract

In the presented work features of interpretation of luminescent spectral dependence properties of ZnO films on sapphire are given. For complex analysis, films of ZnO of different thickness obtained in oxygen medium at different substrate temperatures are considered using the stage of recrystallysis annealing. It is shown that only a red (650 – 1000 nm) band ZnO sapphire substrate is observed in the spectrum of cathodoluminescence of thin films obtained at low temperature of the substrate, and luminescence of the film ZnO fed by excessive defect. Prolonged recrystallization annealing results in improved quality of thin ZnO films and a broad (430 – 740 nm) band in the ZnO. With an increase the film thickness, only bands associated with ZnO appear in the cathodoluminescence spectra: the edge luminescence band (maximum 390 nm) and the red band (500 – 950 nm with a maximum in the region of 710 nm) are associated with charged zinc vacancies. Focusing the beam leads to local heating of the sample and an increase in the concentration of interstitial zinc. This is due to the displacement of the edge light band into the 410 nm region, as well as the blue mixing of the defective luminescence band.