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Vanadium dioxide is a good and attractive material for application of smart window coating and sensor. The main objective of this research is to fabricate and characterize the tungsten doped vanadium dioxide thin films. Sol-gel spin coating method was used because this technique was a good process for preparing the pure vanadium dioxide (VO2) thin films. Five samples of tungsten doped VO2 thin films with different annealing times parameter were fabricated on quartz substrates. Isopropanol was used as the precursor that added to the tungsten doped vanadium dioxide. All samples have been characterized for the surface morphology and thickness using field emission scanning electron microscopy (FESEM). While the electrical properties were measured by current-voltage (I-V) measurement system and the optical properties were characterized via ultraviolet-visible (UV-Vis) spectrophotometer. A linear graph shows the effect of absorbance of the tungsten-doped vanadium dioxide. Longer annealing treatment at 5 hours and 550 °C results in a lower resistivity and a higher conductivity which are 0.65 Ωm and 1.54 (Ωm)−1 respectively. In a conclusion, the effect of different annealing times successfully characterizes electrical properties, optical properties and surface morphology of tungsten-doped vanadium dioxide thin films. [ABSTRACT FROM AUTHOR]

Light emitting diode (LED) is solid state lighting uses semiconductor material and convert the electrical energy to light energy. Titanium dioxide (TiO2) was used in optoelectronic devices because it is good purity and easily synthesizing onto thin film. TiO2 nanotubes was prepared by electrochemical anodization method at room temperature. The TiO2 nanotubes was investigated amorphous and annealed sample at 450°C. The surface morphology revealed that sample annealed at 450°C showed uniformity with a regular porous on top layer of TiO2. Raman pattern showed the amorphous-to-crystalline anodic TiO2 sample transition with anodization. Optical properties showed the TiO2 nanotubes annealed at 450°C has not sharp absorbance edge and it is relates to the oxygen deficiency in nanotube material. The TiO2 nanotubes film annealed at 450°C has potential apply to LED devices. [ABSTRACT FROM AUTHOR]

Recent investigations of the promising materials for optoelectronic have been demonstrated by introducing n-type inorganic material into conjugated polymer. Morphology, optical and electrical of nanocomposites thin films based on poly[2-methoxy-5-(2’-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and zinc oxide (ZnO) nanotetrapods with various ZnO composition (0 wt% to 0.4 wt%) have been investigated. The MEH-PPV: ZnO nanocomposite thin film was deposited using spin-coating method. Surface morphology was characterized using field emission scanning electron microscopy and shows the uniform dispersion of MEH-PPV and ZnO phases for sample deposited at 0.2 wt%. The photoluminescence (PL) spectra shows the visible emission intensities increased when the ZnO composition increased. The current-voltage (I-V) measurement shows the highest conductivity of nanocomposite thin film deposited at 0.2 wt% of ZnO is 7.40 × 10−1 S. cm−1. This study will provide better performance and suitable for optoelectronic device especially OLEDs application. [ABSTRACT FROM AUTHOR]

Al-doped zinc oxide (AZO) nanorods thin film were deposited on Au catalyst using RF sputtering at 300 °C. The 15 nm thickness Au catalyst were deposited on glass substrates by sputtering method followed by annealing for 15 min at 500 °C to form Au nanostructures on the glass substrate. The AZO thin films were then deposited on Au catalyst at different RF power ranging from 50 – 200 W. The morphology of AZO was characterized using Field Emission Scanning Electron Microscopy while X-ray Diffraction was used to examine crystallinity of AZO thin films. From this work, the AZO nanorods was found grow at 200 W RF power. [ABSTRACT FROM AUTHOR]

Recent investigations of the promising materials for optoelectronic have been demonstrated by introducing ntype inorganic material into conjugated polymer. The optical and electrical of nanocomposite films based on poly[2- methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and zinc oxide (ZnO) nanostructured of various deposition layers (1 to 3 layers) have been investigated. The MEH-PPV: ZnO nanocomposite films were deposited using spin-coating technique. The surface morphology nanocomposite films were characterized using field emission scanning electron microscope. From surface profiler measurement, we found that the thickness of nanocomposite films increased as deposition time increased. The optical properties were measured using photoluminescence spectroscope. The photoluminescence (PL) spectra showed that two deposition layers is the highest intensity at visible region (green emission) due to high energy transfer from particles to the polymer. The current density for two layers sample is due to aggregation of conjugated polymer chain hence form excited interchain exciton for optical excitation. This study will provide better performance and suitable for optoelectronic device especially OLEDs application. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) thin films were prepared on glass substrates by sol-gel method. A homogeneous and stable solution was prepared by dissolving zinc acetate dehydrate in 2-methoxyethanol and monoethanolamine (MEA). ZnO films were obtained by preheating the spin-coated films at 150° C for 10 min after each coating and postheating up to 450° C for 1 h. The growth of ZnO thin film using 0.1 and 0.3 M are not strong due to insufficient of Zn species in the solution which retarded the ZnO growth. For 0.5 M film show that it is composed of a dense packing of associated particles. Cracks are also observed in the thin film with 0.9 M, and they probably originate from the different thermal expansion coefficients of the ZnO film and the substrate. The highest transmittance properties of ZnO thin films at 0.1 M, might be due to the presence of many voids which cover the glass substrate. [ABSTRACT FROM AUTHOR]