Evaluation and Analysis of Aluminium Thinfilm Coatings for Solar Reflectors Application

Abstract

Aluminium thin films are very frequently used and its application rise steeply during the second half of the 20^th century for solar reflectors. The focus was on study aluminium thin films for solar reflectors, which would accomplish by concentrating the solar energy using reflectors. The use of solar reflector to increase solar energy collection is a cheaper alternative to increase the concentration of solar energy. The aim of this research work was to study the optical and mechanical properties of aluminium thinfilm coatings. The thinfilms were characterized by atomic force microscope, UV VIS NIR spectrophotometer, thickness profiler and nano mechanical testing system. The surface morphology of the thinfilm was characterized by using atomic force microscope shows the dense and uniform nanostructures with increased surface roughness from 6 to 25 nm with increasing protective coatings. UV-VIS-NIR spectrophotometer analysis indicates higher reflection factor for all the films within the wavelength vary of 250 nm to 2500 nm. Nano indentation study disclosed that there was a substantial modification in hardness values of the aluminium thin films deposited using DC magnetron sputtering. There are several star reflectors systems used these days with thinfilm coatings, however if the user needs to extend the energy collected and has restricted area for the advance, then the utilization of reflectors with higher protecting layer skinny film coatings is an attractive answer.