Title :
Annealing Effects of Ti/Au Contact on n-MgZnO/p-Si Ultraviolet-B Photodetectors
Author :
Yaonan Hou ; Zengxia Mei ; Huili Liang ; Daqian Ye ; Changzhi Gu ; Xiaolong Du ; Yicheng Lu
Author_Institution :
Beijing Nat. Lab. for Condensed Matter Phys., Inst. of Phys., Beijing, China
Abstract :
Effects of postannealing on Ti/Au-MgZnO contact and n-MgZnO/p-Si heterojunction ultraviolet-B photodetector´s performance are investigated. It is found that the out diffusion of oxygen from MgZnO and its bonding with Ti at the interface have significant influences on the properties of Ti/MgZnO interface and photodetector. The persistent photocurrent observed in the annealed device is attributed to the oxygen vacancies near the interface, consistent with the theoretical calculations. It is revealed that the reaction at metal/MgZnO interface possibly plays a key role and even dominates the MgZnO p-n heterojunction ultraviolet detectors´ performances.
Keywords :
II-VI semiconductors; annealing; diffusion; elemental semiconductors; gold; magnesium compounds; photoconductivity; photodetectors; semiconductor heterojunctions; semiconductor-metal boundaries; silicon; titanium; ultraviolet detectors; vacancies (crystal); wide band gap semiconductors; zinc compounds; Ti-Au-MgZnO-Si; Ti/Au-MgZnO contact; bonding; metal/MgZnO interface; n-MgZnO/p-Si heterojunction ultraviolet-B photodetector; oxygen diffusion; oxygen vacancies; photocurrent; postannealing effects; Annealing; Detectors; Electrodes; Gold; Photoconductivity; Photodetectors; Zinc oxide; MgZnO; metal–semiconductor contact; persistent photocurrent (PPC); ultraviolet photodetector;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2013.2278894
