Abstract
ZnO thin films were grown onto chemically and ultrasonically cleaned heated and unheated glass substrates in a vacuum of 10-6 mbar by using oil diffusion pump. The optical properties of the films have been ascertained by UV-VIS-NIR spectrophotometry in the photon wavelength range of 300 – 2500 nm. The effect of substrate temperature on the optical properties of the films has been investigated, where all film thickness was kept fixed at 100 10 nm. Bang gap and Urbach energy values of the films were calculated. Surface topography studied by Atomic Force Microscopy (AFM) measurements showed a uniform film texture. The extent and nature of transmittance and optimized band gap of the material make possible to use it for optoelectronic applications..
Keywords
ZnO thin film, Vacuum evaporation, Optical properties, Urbach energy.
Citation
F. CHOWDHURY, KH. S. BEGUM, S. M. FIROZ HASAN, M. S. ALAM, Effects of substrate temperature on the optical properties of vacuum evaporated ZnO thin films, Optoelectronics and Advanced Materials - Rapid Communications, 5, 4, April 2011, pp.356-359 (2011).
Submitted at: March 5, 2011
Accepted at: April 11, 2011