Postannealing Effect at Various Gas Ambients on Ohmic Contacts of Pt/ZnO Nanobilayers toward Ultraviolet Photodetectors
Open Access
- 18 December 2013
- journal article
- research article
- Published by Hindawi Limited in International Journal of Photoenergy
- Vol. 2013, 1-9
- https://doi.org/10.1155/2013/372869
Abstract
This paper describes a fabrication and characterization of ultraviolet (UV) photodetectors based on Ohmic contacts using Pt electrode onto the epitaxial ZnO (0002) thin film. Plasma enhanced chemical vapor deposition (PECVD) system was employed to deposit ZnO (0002) thin films onto silicon substrates, and radio-frequency (RF) magnetron sputtering was used to deposit Pt top electrode onto the ZnO thin films. The as-deposited Pt/ZnO nanobilayer samples were then annealed atin two different ambients (argon and nitrogen) to obtain optimal Ohmic contacts. The crystal structure, surface morphology, optical properties, and wettability of ZnO thin films were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), photoluminescence (PL), UV-Vis-NIR spectrophotometer, and contact angle meter, respectively. Moreover, the photoconductivity of the Pt/ZnO nanobilayers was also investigated for UV photodetector application. The above results showed that the optimum ZnO sample was synthesized with gas flow rate ratio of 1 : 3 diethylzinc [DEZn, Zn(C2H5)2] to carbon dioxide (CO2) and then combined with Pt electrode annealed atin argon ambient, exhibiting good crystallinity as well as UV photo responsibility.
Keywords
Funding Information
- National Science Council (NSC 101–2221-E-027-042)
This publication has 29 references indexed in Scilit:
- High performance ZnO:Al films deposited on PET substrates using facing target sputteringApplied Surface Science, 2013
- Optical Properties Characterization of InGaN/GaN near UV Photodetector with Surface Nano-Structure Fabricated by Nano-ImprintingAdvanced Materials Research, 2011
- AlGaN Schottky Diodes for Detector Applications in the UV Wavelength RangeIEEE Transactions on Electron Devices, 2009
- Characterization of diamond ultraviolet detectors fabricated with high-quality single-crystalline chemical vapor deposition filmsApplied Physics Letters, 2009
- Persistent photoconductivity in p-type ZnO(N) grown by molecular beam epitaxyApplied Physics Letters, 2007
- GaN UV photodetector by using transparency antimony-doped tin oxide electrodeJournal of Crystal Growth, 2007
- ZnO thin film photoconductive ultraviolet detector with fast photoresponseJournal of Crystal Growth, 2006
- ZnSe MSM photodetectors prepared on GaAs and ZnSe substratesMaterials Science and Engineering B, 2005
- Photoconductive UV detectors on sol–gel-synthesized ZnO filmsJournal of Crystal Growth, 2003
- Pulsed laser reactive deposition of p-type ZnO film enhanced by an electron cyclotron resonance sourceJournal of Crystal Growth, 2001