کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5357488 1503608 2015 21 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Correlation between structural and electrical properties of PLD prepared ZnO thin films used as a photodetector material
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Correlation between structural and electrical properties of PLD prepared ZnO thin films used as a photodetector material
چکیده انگلیسی
The electrical transport properties of a set of zinc oxide (ZnO) thin films, prepared by pulsed laser ablation, were investigated at the temperatures of 30 K and 300 K. Information about the structural and morphological properties of the samples were obtained by means of atomic force microscopy (AFM) and X-ray diffraction (XRD). A significant variation in the surface morphology and photoresponse characteristics of the ZnO thin films were observed as a function of the deposition temperature. Upon increasing the deposition temperature, the surface topography changes from a more fine-grained to a more coarse-grained structure, showing a tetragonal wurtzite crystalline structure. Time resolved photocurrent measurements showed significantly variations as function of the observed samples morphologies. A photocurrent value of about three order of magnitude larger is observed for samples showing a more coarse-grained structure with respect to the fine-grained ones. Such a result is interpreted as due to the contributions of both “bulk” and defect centers that affect the conduction mechanisms and influence both the photoconductivity values and the photoresponse speed. The observed decay times are very long with respect to films grown by other techniques, due to the reduction of the surface localized centers of defect available for recombination. In this context, the sample morphology appears to be a key parameter to control the photoconductivity in ZnO thin films.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Surface Science - Volume 359, 30 December 2015, Pages 266-271
نویسندگان
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