Processing and characterisation of nanostructured Al doped ZnO antireflection films

Al doped ZnO films (3 at-%) were developed on soda lime glass substrate by electroless deposition. The films were characterised by X-ray diffraction (XRD), field scanning electron microscope (FESEM/EDS), atomic force microscope (AFM) and UV visible spectrophotometer. X-ray diffraction analysis indicates that preferential growth of the films are (101) reflection peak in the 400, 500 and 600°C annealed films. FESEM surface and cross-section analysis exhibit that Al doped ZnO film has dense and compact grains as compared to undoped ZnO film. Film is composed of Zn, Al and O is confirmed by EDS analysis. Surface roughness of the film is determined by AFM. The Al doped ZnO films exhibit excellent optical transmittance (more than 80%) and minimum absorbance spectra in visible range 400–800 nm wavelength. Al doped ZnO film annealed at 500°C is suitable for antireflection coating in silicon solar cell.