کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5367300 | 1388364 | 2009 | 5 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Photosensitivity of nanocrystalline ZnO films grown by PLD Photosensitivity of nanocrystalline ZnO films grown by PLD](/preview/png/5367300.png)
We have studied the properties of ZnO thin films grown by laser ablation of ZnO targets on (0 0 0 1) sapphire (Al2O3), under substrate temperatures around 400 °C. The films were characterized by different methods including X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and atomic force microscopy (AFM). XPS analysis revealed that the films are oxygen deficient, and XRD analysis with θ-2θ scans and rocking curves indicate that the ZnO thin films are highly c-axis oriented. All the films are ultraviolet (UV) sensitive. Sensitivity is maximum for the films deposited at lower temperature. The films deposited at higher temperatures show crystallite sizes of typically 500 nm, a high dark current and minimum photoresponse. In all films we observe persistent photoconductivity decay. More densely packed crystallites and a faster decay in photocurrent is observed for films deposited at lower temperature.
Journal: Applied Surface Science - Volume 255, Issue 11, 15 March 2009, Pages 5917-5921