Advanced Materials Research Vol. 667

Abstract: The optical and structural properties of Zinc Oxide (ZnO) nanostructures is prepared by sol-gel immersion method at different temperature on Porous Silicon (PSi) Substrates. PSi is produced from the Si by using electrochemical etching process. The ZnO solution is prepared by using the sol-gel immersion method. Parameters such as different deposition time were studied. The optical properties of ZnO Nanostructures will be characterized by using PL and SEM. The structural properties of ZnO Nanostructures will be characterized by using XRD. The result of investigation show that the growth of ZnO nanostructures improving as the deposition temperature increase.

Abstract: Fermented tapioca which is a new starting material was used as a carbon precursor. Carbon nanotubes (CNTs) were deposited on silicon wafer (Si) by Thermal Chemical Vapor Deposition (TCVD). The gas flow of Argon (Ar) was constant at 70 bubbles per minute and 20 minutes of deposition time. Before the deposition process, silicon was coated with Nickel using spin coater. Various parameters such as amount of inoculums have been studied. Surface morphology and uniformity were characterized using FESEM. The surface morphology and uniformity of CNTs are dependents on parameters used. The optimum CNTs that produced using Thermal CVD was 1.5 wt% of inoculums due to the size and the uniformity of CNTs growth.

Abstract: Zinc Oxide thin film has been prepared by sol-gel spin-coating techniques and has three steps preparation were includes. They were solution preparation, thin film deposition and characterization process. The film were prepared to investigate the annealing temperatures depend with two environments were hot and room temperatures. Annealing temperatures were set up into five temperatures 200°C, 300°C, 400°C, 500°C, and 600°C were heated inside furnace. The characterization of ZnO thin film was measured by UV-Vis Spectrometry which to measure the transmittance of ZnO have when through the medium. The transmittance was investigated by use glass as a substrate. The optical properties showed when increased annealing temperatures, so the high UV was transmit. From that, the absorption coefficient of ZnO also can also investigate too. The surface morphology in increasing annealing temperature has a small size and less porosity between particles.

Abstract: Titanium Dioxide (TiO2) thin films have been prepared on glass substrates by using sol-gel method and spin-coating technique. The samples have been annealed at temperatures of 350°C ~ 500oC. The electrical and structural properties of the thin films due to the changes of annealing treatment process were investigated by 2 point probes I-V measurement and X-ray Diffraction (XRD) respectively. The result show that resistivity of the thin film decreased with annealing temperatures. XRD characterization indicates crystalline structure of TiO2 thin films improved as annealed at higher temperatures.

Abstract: This paper focus on zinc oxide (ZnO) nanorods prepared using sol-gel immersion method immersed at different time. Immersion times have been varied 1~24 hr and the characteristics of each sample have been observed. The effects of immersion time on ZnO nanorods thin films have been studied in surface morphology and structural properties using Scanning Electron Microscopy (SEM) and X-ray diffractometer (XRD), respectively.

Abstract: We have investigated the morphology and sensitivity characteristics of nanostructured ZnO thin film prepared by sol-gel method from different molarities of zinc nitrate hexahydrate and hexamethylenetetramine (HMT) solutions. ZnO thin film coated glass substrates were used to growth the ZnO structures and have been annealed at different temperatures. The morphology of the samples was observed by scanning electron microscopy (SEM) and their sensitivity characteristics were measured by using the I-V measurement. The SEM studies shows that the nanostructured ZnO was denser at higher molarities and I-V measurement demonstrates that the nanostructured ZnO having higher sensitivity at higher molarities and higher annealing temperatures.

Abstract: The electrical properties of nanostructured Aluminum (Al) doped Zinc Oxide (ZnO) thin films based ultraviolet (UV) sensor prepared by sol-gel spin-coating method have been investigated. Uniform nanoparticles Al doped ZnO have been deposited with high absorption coefficient at UV region and low absorption coefficient properties in visible and near-infrared (NIR) region. I-V spectra show high sensitivity characteristic of UV sensor with fast response after UV light exposure.

Abstract: We investigated the effect of immersion time on optical, electrical properties and surface morphology of nanostructured Aluminium (Al) doped Zinc Oxide (ZnO) thin films prepared by immersion technique. UV-Vis-NIR spectra indicate that the transmittance of the samples decrease with immersion time. Electrical properties study reveals the nanostructured Al doped ZnO thin film at 1 hr shows the lowest resistivity compared to other samples. Surface morphology results as characterized by scanning electron microscope (SEM) show that the Al doped ZnO nanorods quantity increased with immersion time.

Abstract: Zinc oxide (ZnO) is a one of the most interesting compound semiconductors that received more attention during last few years due to its unique properties. Due to that, this study has been done to manipulate those properties to be used for FET applications. The ZnO thin film has been deposited using the thermal chemical vapor deposition. This is done in a double furnace, which vapored the ZnO powder at different temperature. The growth of the ZnO thin film has been observed using SEM and the electrical properties has been analyzed by using I-V probe station. This is done to study the diode characteristics of ZnO thin film to be used in FET applications.

Abstract: The characterized on porous silicon layer by using photoluminescence (PL) and I-V measurement (I-V) has been done. Porous silicon was formed by electrochemical etching on (100) p-type Si wafer substrate with the constant current density (20mA/cm2) and variable the etching time. The samples ware prepared under various etching time and properties of porous silicon depend on an etching time. Porous silicon has been used in humidity sensors to detect humidity through changes of its electrical properties. The samples of porous silicon were characterized by using Photoluminescence Spectroscopy (PL) that used to characterize optical properties while I-V Measurement (I-V) used to characterize porous silicon junction properties using a linear voltage source. The result shows PL intensity is increase while the wavelength is decrease for etching time of PSi is longer. For the I-V measurement result shows the etching time affect the resistance of sample due to its porosity.