AVS 51st International Symposium
    Thin Films Tuesday Sessions
       Session TF1-TuM

Paper TF1-TuM3
Multi-layered ITO and SiO@sub 2@ Thin Films Deposited on Plastic Substrates by Vacuum Arc Plasma Evaporation

Tuesday, November 16, 2004, 9:00 am, Room 303C

Session: Thin Films on Flexible and Polymer Substrates
Presenter: T. Miyata, Kanazawa Institute of Technology, Japan
Authors: T. Miyata, Kanazawa Institute of Technology, Japan
Y. Minamino, Kanazawa Institute of Technology, Japan
T. Minami, Kanazawa Institute of Technology, Japan
Correspondent: Click to Email
Recently, a vacuum arc plasma evaporation (VAPE) method that provides a high rate deposition on large area substrates has been newly developed. This paper describes the preparation of multi-layered structures composed of ITO and SiO@sub 2@ thin films deposited on plastic substrates by the VAPE method. Structures such as ITO/SiO@sub 2@ and ITO/SiO@sub 2@/ITO were prepared for the purpose of improving the optical transmittance of flexible transparent conducting films that exhibit a desirable sheet resistance, e.g., ITO thin films deposited on thick PET films. The ITO and SiO@sub 2@ thin films were prepared on PET substrates by the VAPE method using sintered ITO and fused quartz fragments, respectively, as targets. The film depositions were carried out under the following conditions: substrate, PET (glass used as a monitor); substrate temperature, 100°C; pressure, 0.08 to 1 Pa; Ar and O@sub 2@ gas flow rates, 20 and 0 to 20 sccm; and cathode plasma power, 4.5 to 10 kW. The optical and electrical properties of the ITO thin films were strongly dependent on the deposition conditions. In addition, the optical transmission spectra of the SiO@sub 2@ thin films also were affected by the deposition conditions. By optimizing the deposition conditions, highly transparent and conductive ITO thin films were prepared at 100°C on both PET and glass substrates. The resistivity of ITO thin films increased from 2.9 to 7.8X10@super –4@@ohm@cm as the O@sub 2@ flow rate was increased from 5 to 20 sccm. In addition, SiO@sub 2@ thin films that were prepared on PET substrates under optimized conditions exhibited a high transmittance in the visible region. Using optimized deposition conditions, ITO/SiO@sub 2@ and ITO/SiO@sub 2@/ITO multi-layered structures with a desirable sheet resistance were prepared on PET substrates based on the theoretical calculation. However, the film thickness of the ITO top layer was determined by the desired sheet resistance. In conclusion, transmittance could be successfully improved in transparent and conductive ITO/SiO@sub 2@ and ITO/SiO@sub 2@/ITO multi-layered structures prepared on flexible plastic substrates by the VAPE method.