Synthesis and characterization of ZnO micro-rods and temperature-dependent characterizations of heterojunction of ZnO microrods/CdTe and ZnO microrods/ZnTe structures

OLGAR M. A., Atasoy Y., BACAKSIZ E., AYDOĞAN Ş.

SENSORS AND ACTUATORS A-PHYSICAL, vol.261, pp.56-65, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 261
  • Publication Date: 2017
  • Doi Number: 10.1016/j.sna.2017.04.053
  • Journal Name: SENSORS AND ACTUATORS A-PHYSICAL
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.56-65
  • Keywords: Microrods, Heterojunction, XRD, SEM, CDTE THIN-FILM, P HETEROJUNCTION, SOLAR-CELLS, ARRAYS, NANORODS, GROWTH, ENHANCEMENT, PERFORMANCE, CONTACTS, ZNO/ZNS
  • Karadeniz Technical University Affiliated: Yes

Abstract

ZnO microrods were fabricated on ZnO-coated SnO2 glass substrates by spray pyrolysis method. To obtain p-n heterojunction, p type CdTe and ZnTe layers were deposited on ZnO microrods. The structural characterizations demonstrated that ZnO microrods have a hexagonal wurtzite structure with vertically aligned rod morphology. Additionally, hexagonal rod geometry was compressed by coating CdTe layer on micro-sized ZnO rods. The diode type rectifying behaviour of ZnO microrods/CdTe and ZnO microrods/ZnTe heterojunctions have been carried out and the electrical characteristics of both devices have been analyzed with current-voltage measurements as a function of temperature. Although the mismatch between ZnO and ZnTe, the ZnO microrods/ZnTe heterojunction showed good rectifying behaviour at all temperatures. According to the our findings, both ideality factor n and barrier height Phi(b) are temperature dependent due to the deviation from pure thermionic emission theory and inhomogeneity at the interface of ZnO-CdTe and ZnO-ZnTe. (C) 2017 Elsevier B.V. All rights reserved.