Papers by Keyword: Spin Coat

Abstract: Nanostructured zinc oxide (ZnO) were successfully prepared by using phyto assisted solution immersion process. ZnO were grown on a glass substrate coated with ZnO nanoparticle thin-film as seed layer at annealing temperature of 450°C. The fabricated nanostructured ZnO exhibit absorption at ∼375 nm as revealed from the UV-visible absorption spectrum, and it is comparable with ZnO nanostructured synthesized from hexamethylenetetramine (HMTA). X-ray diffraction (XRD) measurement revealed a sharp peak corresponding to the hexagonal wurtzite structure of nanostructured ZnO. Field emission scanning electron microscopy (FESEM) showed average size of ZnO at 24.15 nm slightly smaller compared to synthesized from HMTA; 30.54 nm. It should also be highlighted that the needs of using this alternative green method are due to the advantages of low working temperature and cost-effective, and with the least possible damage to the environment.

Abstract: Silicon oxide thin film was formed using reaction of spin-coated dimethyl-silicone-oil and 5% ozone gas at low temperature of 300°C. Silicone oil is used for lubrication, insulation, and so on, and it is inexpensive and easy to deal with owing to its stability. FT-IR spectrum of the formed silicon oxide film was similar to that of the thermally oxidized film, and we hardly observed peaks of Si-CH₃ and C-H bonds originated in silicone oil. The Si-OH bonds in the film were observed. The Si-OH bond causes the degradation of the electric properties of the insulator. In order to remove the Si-OH bonds, the silicon oxide film was treated with an argon excimer light at room temperature. The wavelength of the light was 126 nm. The amount of Si-OH bond was drastically reduced by the UV annealing. The energy of the UV light is high and the value is 9.8 eV. The high energy light may cut the bond of Si-OH. Therefore, the amount of Si-OH bond could be reduced.

Abstract: Poly(tetrafluoroethylene)(PTFE) thin films were coated onto metal substrates by a spin coat apparatus, vacuum evaporator and RF sputtering, and their adhesion and friction properties evaluated. PTFE thin film coated onto nickel-titanium (Ni-Ti) substrate by spin coating showed a low friction coefficient, however pull strength between the thin film and Ni-Ti substrate was low. In order to increase the pull strength, PTFE and poly(vinyl alcohol) (PVA) composite thin films were introduced between the PTFE thin film and Ni-Ti substrate by spin coating. PTFE thin film was also coated onto SUS302 substrate by a vacuum evaporator. This PTFE thin film showed poor adhesion to the SUS302 substrate. The adhesion was enhanced by heating of the substrate during the evaporation. In addition, a PTFE and ethylene vinyl alcohol (EVOH) composite thin film showed higher adhesion strength than that of the PTFE thin film. Poly(fluorocarbon) thin films were prepared by a conventional RF sputtering with PTFE target. These thin films showed a higher friction coefficient than that of the pristine PTFE. Molecular structures of the poly(fluorocarbon) thin films prepared by RF sputtering were different from the pristine PTFE. This difference may have influenced the friction coefficient. The pull strength of metal thin films such as gold, copper, nickel and aluminum deposited on the sputtered PTFE thin films by vacuum evaporation was measured. The nickel thin film adhered to the PTFE thin film most strongly of all the thin films.