Postannealing Effect at Various Gas Ambients on Ohmic Contacts of Pt/ZnO Nanobilayers toward Ultraviolet Photodetectors. (18th December 2013)

• Record Type: Journal Article
• Authors: Chao, Chung-Hua; Chen, Mao-Yi; Lin, Chii-Ruey; Yu, Yueh-Chung; Yao, Yeong-Der; Wei, Da-Hua
• Other Names: Meen Teen-Hang Academic Editor.
• Is Part Of: International journal of photoenergy. Volume 2013(2013)
• Publication Date: 2013-12-18
• Subjects: Photochemistry -- Periodicals; Photobiology -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Photochimie; Photobiologie; Chimie physique et théorique; Chemistry, Physical and theoretical; Photobiology; Photochemistry; Electronic journals; Periodicals; 541.35
• DOI: 10.1155/2013/372869
• Languages: English
• ISSNs: 1110-662X

Abstract

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 at 450 ∘ C in 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(C2 H5 )2 ] to carbon dioxide (CO2 ) and then combined with Pt electrode annealed at 450 ∘ C in argon ambient, exhibiting good crystallinity as well as UV photo responsibility.