Exciton Photoluminescence of ZnO Thin Films Grown by ALD-Technique

The low-temperature exciton photoluminescence of thin ZnO films grown by atomic layer deposition (ALD) on (100) and (111) Si substrates under He-Cd (λ = 325 nm) and N2 (λ = 337 nm) laser excitation is studied. The structure of the films is analyzed by XRD and SEM methods. The effects of excitation intensity and laser irradiation on the photoluminescence spectra are investigated. A wide asymmetric emission band attributed to excitons localized in the near surface potential fluctuations has been observed in photoluminescence spectra of the film and powder samples.