Study of the spectral response in the visible spectral region the ZnSe thin films
Main Article Content
Keywords
ZnSe thin films, Photoconductivity, SEM.
Abstract
In this work are presented results in the study of photoconductivity of ZnSe thin films deposited on glass substrates at different temperatures, under high vacuum using thermal evaporation technique. The effect of substrate temperature on the spectral photoconductivity and morphological properties of ZnSe thin films were studied. For the measurements of photoconductivity copper contacts were deposited on the samples. Spectral responses were obtained for samples of between 290 and 500 nm. In all samples the signal present two contributions associated with transitions E(Γ7V – Γ6C) and Eg(Γ8V – Γ6C) , with average values energy of 3.35 and 2.80 eV, respectively. The response time of the sample is associated with the morphology of the samples. In the prepared samples were obtained at lower temperatures response times on the order of seconds, whereas the time decreases by one order of magnitude in the samples prepared at the substrate temperature of 250 C.
PACS:73.50pz
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