Nano Archive

Structural and optical properties of nano-structured tungsten-doped ZnO thin films grown by pulsed laser deposition

Ngom, B D and Mpahane, T and Manyala, N and Nemraoui, O and Buttner, U and Kana Kana, J B and Fasasi, A.Y. and Maaza, M. and Beye, A.C. (2009) Structural and optical properties of nano-structured tungsten-doped ZnO thin films grown by pulsed laser deposition. Applied Surface Science, 225 . pp. 4153-4158.

[img]
Preview
PDF - Published Version
Available under License Creative Commons Attribution Non-commercial.

945Kb

Abstract

Novel highly c-oriented tungsten-doped zinc oxide (WZO) thin films with 1 wt% were grown by pulsed laser deposition (PLD) technique on corning 1737F glass substrate. The effects of laser energy on the structural, morphological as well as optical transmission properties of the films were studied. The films were highly transparent with average transmittance exceeding 87% in the wavelength region lying between 400 and 2500 nm. X-ray diffraction analysis (XRD) results indicated that the WZO films had caxis preferred orientation with wurtzite structure. Film thickness and the full width at half maximum (FWHM) of the (0 0 2) peaks of the films were found to be dependent on laser fluence. The composition determined through Rutherford backscattering spectroscopy (RBS) appeared to be independent of the laser fluence. By assuming a direct band gap transition, the band gap values of 3.36, 3.34 and 3.31 eV were obtained for corresponding laser fluence of 1, 1.7 and 2.7 J cm/2, respectively. Compared with the reported undoped ZnO band gap value of 3.37 eV, it is conjectured that the observed low band gap values obtained in this study may be attributable to tungsten incorporation in the films as well as the increase in laser fluence. The high transparency makes the films useful as optical windows while the high band gap values support the idea that the films could be good candidates for optoelectronic applications.

Item Type:Article
Subjects:Analytical Science > Microscopy and probe methods
Material Science > Nanofabrication processes and tools
Material Science > Nanostructured materials
Analytical Science > Beam methods
ID Code:7248
Deposited By:Dr Balla Diop Ngom
Deposited On:05 Oct 2009 07:13
Last Modified:05 Oct 2009 07:13

Repository Staff Only: item control page