標題: | Dark current suppression of amorphous selenium based photosensors by the ZnO hole blocking layer |
作者: | Yu, Tung-Yuan Pan, Fu-Ming Chang, Cheng-Yi Hu, Tien Chen, Jenn-Fang Wang, Jia-Feng Lin, Cheng-Lu Chen, Tsung-Han Chen, Te-Ming 材料科學與工程學系 電子物理學系 Department of Materials Science and Engineering Department of Electrophysics |
關鍵字: | Zinc oxide;Amorphous Se;Hole blocking layer;Oxygen vacancy;DLTS |
公開日期: | 1-五月-2014 |
摘要: | To study the influence of defects in the hole blocking layer (HBL) on the dark current of amorphous selenium (a-Se) based photosensors, we prepared ZnO thin films by reactive sputter deposition (RSD) for the use as the HBL of the photosensors. The ZnO HBL layers prepared with different oxygen flow rates were characterized by X-ray photoelectron spectroscopy, Raman scattering analysis and photoluminescence, indicating that the density of oxygen vacancies in the ZnO thin films is significantly affected by the oxygen flow rate. The deep level transient spectroscopy measurement reveals two hole trap levels present in the RSD deposited ZnO thin films; one is at 0.94 eV and the other at 0.24 eV above the valence band edge. The electrical performance of the a-Se photosensor is largely influenced by the amount of oxygen vacancies in the ZnO thin film. The a-Se photosensor with the ZnO HBL of the most oxygen vacancies has the lowest dark current and demonstrates the highest breakdown field. (C) 2014 Elsevier B.V. All rights reserved. |
URI: | http://dx.doi.org/10.1016/j.cap.2014.02.011 http://hdl.handle.net/11536/24457 |
ISSN: | 1567-1739 |
DOI: | 10.1016/j.cap.2014.02.011 |
期刊: | CURRENT APPLIED PHYSICS |
Volume: | 14 |
Issue: | 5 |
起始頁: | 659 |
結束頁: | 664 |
顯示於類別: | 期刊論文 |