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In this work, silicon dioxide (SiO2) films were fabricated on indium tin oxide (ITO) coated glass substrates by radio frequency (RF) magnetron sputtering deposition technique. The deposition rate of the magnetron sputtered SiO2 films was investigated. The SiO2 films were characterized with the atomic force microscopy (AFM) for their surface topology. In addition, the electrical insulating strength of the magnetron sputtered SiO2 was examined.

In this work, ZnO films were fabricated by sol-gel spin coating technique. Different spinning speeds of 1000 to 6000 revolutions per minute (RPM) were used in order to study the changes on the properties of the ZnO films. The characterizations were conducted using surface profilometer for thickness measurement, atomic force microscopy (AFM) for surface scanning, X-ray diffractometer (XRD) for structural analysis, and ultraviolet-visible (UV-VIS) spectrophotometer for optical transmittance. The influence of spinning speed and the mechanisms which affect the growth of the ZnO films will be revealed.

In recent years, as a ceramic semiconducting material, zinc oxide (ZnO) has received great attention in sensing applications, including ultra-violet (UV), gas, and humidity sensors. In this work, ZnO based humidity sensors were fabricated on thermally oxidized silicon substrates. The contact electrodes for the sensors were realized using patterned aluminium (Al) films. ZnO films were deposited on the substrates as the active layer for the sensors using radio frequency (RF) magnetron sputtering technique. The electrical properties of the sensors were tested in various relative humidity (RH) levels. The ZnO humidity sensors have showed a decrease in resistance with increasing humidity level. The fabrication process and the characteristics of the ZnO humidity sensors will be revealed in this work.

The Zinc Oxide (ZnO) films were fabricated on glass coated with indium tin oxide (ITO) substrate by sol-gel spin coating technique. With regard to the preheating temperatures, the effects of growth mechanism ZnO films on the optical and structural properties were investigated. In this study, the preheating temperatures were varied from 250°C, 280°C, and 300°C. The X-ray diffraction (XRD) and ultraviolet-visible (UV-Vis) spectroscopy were used to examine the structural and optical properties of the ZnO films. The XRD results revealed that, the ZnO films are highly crystalline for all samples which are dominated by (002) peak orientation. Meanwhile, observation from optical results indicated that, the variation of transmittance spectra were turn out and it is proportional to the preheating temperatures used. Overall, we realized that the properties of the ZnO films in the sol-gel spin coating technique strongly depend on the preheating temperature and need to be considered as important factor to obtain the high-quality of the ZnO films. Keywords: Sol-gel, Zinc oxide film, X-ray diffraction

Aluminium (Al) doped zinc oxide (ZnO) has been considered as one of the promising transparent conducting oxide for wide applications in electronic devices. In this investigation, sol-gel spin coating process were employed to fabricate Al:ZnO on glass coated with indium tin oxide (ITO) substrate. In order to expose the effects of aluminium concentration on the structural and electrical properties of the ZnO films, different Al concentrations (1 at.%, 3 at.% and 5 at.%) were used. A field emission scanning electron microscope (FESEM) and a two point probe were employed to examined the material properties of the Al:ZnO films. Through the FESEM results, the Al:ZnO films show different morphologies behaviour with increasing the Al concentrations. Besides, the electrical conductivity was increased by increasing the dopant source and the lowest resistivity was obtained at 5 at.%. In general, the Al concentration exerts strong influence on the ZnO films properties. Keywords: Transparent conducting oxide, X-ray diffraction, sol gel

In this paper, direct current plasma magnetron sputter deposition technique was employed to deposit zinc oxide (ZnO) films on glass substrates. The magnetron sputtering process parameters including film thickness and substrate temperature were investigated. The crystallite sizes of the ZnO films were extracted from the measured X-ray diffraction patterns. The correlation of the crystallite size of the ZnO films with the film thickness and the substrate temperature will be discussed in this paper.

Zinc oxide (ZnO) is a promising electronic material for a variety of large area electronic applications including thin-film sensors, transistors, and solar cells. Various techniques have been focused and explored to synthesize ZnO films. In this study, sol-gel process was adopted as the fabrications process to grow the ZnO films. Three different types of solvents were used including ethanol, isopropanol and ethylene glycol as the reaction medium in the ZnO solution. The correlation between different solvents used and the properties of the ZnO films was explored and observed. The surface morphologies, structural and optical properties were examined using field émission scanning electron microscope (FESEM), X-ray diffractometer (XRD) and ultraviolet-visible (UV-Vis) spectroscopy. Through the observation from FESEM results, the surface morphology changed when different solvents were used. The crystallographic structures of the ZnO films demonstrate high crystallinity, and the extracted crystallite size is around 30 nm. Furthermore, ZnO films synthesized using isopropanol and ethylene glycol exhibit high transmittance spectra greater than 80% in the visible region. In general, the experimental results revealed that different solvents in the sol-gel process exert influences on the properties of the ZnO films.

Ultraviolet (UV) sensors have variety of applications. In this work, a new transparent UV sensor is developed based on zinc oxide (ZnO) films. The ZnO films with 350 nm thicknesses were fabricated on glass substrates by using direct current (DC) plasma magnetron sputtering technique. The ZnO UV sensors are characterised by using current-voltage (I-V) measurements at room temperature. The current is measured by applying small bias voltage under the white light, UV light (325 nm), and dark condition and the photocurrent responses extracted from the I-V measurements are compared. The transparent UV sensors based on ZnO films deposited at high substrate temperature of 450 °C exhibit most significant photocurrent response under UV irradiation.