Abstract:
Zinc oxide (ZnO) thin films were successfully deposited on glass
substrate by radio frequency (RF) sputtering technique. One set of the samples
was annealed in open air at temperatures of 423 K, 573 K and 723 K for one
hour while another set of samples was annealed under nitrogen atmosphere for
the same duration of time and temperature as the other set. A growth
mechanism for thin film growth by RF sputtering has been presented. The films
were also characterised to assess their optical properties. The ZnO thin films
showed good transmittance, low reflectance and good absorbance in the visible
region. The energy band gap (Eg) obtained is in the range of (3.15–3.28 eV)
which is good for window layer of a solar cell. Other optical constants
evaluated include refractive index and the extinction coefficient.
