Structural and opto-electrical properties of Al doped ZnO sputtered thin films

Abstract

Transparent and conductive aluminum-doped zinc oxide (AZO) thin films with high preferential c-axis orientation have been deposited on glass substrates by radio frequency magnetron sputtering method of ZnO and DC magnetron sputtering of Al. Structural, surface morphology, optical and electrical properties of ZnO thin films were studied by X-ray diffraction, scanning electron microscope, ultraviolet-visible spectrophotometer, surface plasmon spectroscopy and Hall effect measurements. The results show that AZO films are polycrystalline and exhibit the hexagonal wurzite crystal structure with a preferred orientation along (002) direction. When DC sputtering power supplied to Al target increases, the crystallinity decreases while the electrical resistivity increases. The average measured transmittance exceeded 75 % in the visible range for all AZO thin films. The band gap values increase with decreasing the Al concentrations.

A comparative study of multi- and mono-layer structures for bulk and thin film plasmonic sensing

“…These plasmonic modes enable the manipulation of light at the nanoscale resulting in field enhancement and bound waves at interfaces. The sensitivity of these plasmonic effects to changes at the metal/dielectric boundary has been employed for various applications 2,3 , for example, plasmonic sensors which are highly sensitive to changes in refractive index of surrounding medium making them suitable for chemical and biomolecular detection 4 . This principle is applied in surface plasmon resonance (SPR) and localized surface plasmon resonance (LSPR) sensors that can specifically or sensitively detect molecules like DNA 5 , proteins 6 , and chemicals 7 .…”