TEMPERATURE AND TIME DEPENDENCE OF EMISSION PROPERTIES OF ZnO FILMS DEPOSITED ON Si SUBSTRATES

Abstract

The emission properties of ZnO films deposited on Si substrates by reactive dc sputtering have been studied using synchrotron radiation (SR). The integrated luminescence spectra as well as the spectra at a fast time window from about 4 ns to 8 ns and a slow time window from about 20 ns to 160 ns were measured simultaneously, at a temperature range from several K to 300 K. Apart from the bound-exciton radiation recombination (peaked at 369.5 nm) and ultraviolet emission band (peaked at 380 nm), a new emission band peaked at 290 nm was found for the first time under SR vacuum ultraviolet excitation. The mechanisms of these photoluminescence emissions are discussed.