AVS 50th International Symposium
    Nanotubes Wednesday Sessions
       Session NT-WeP

Paper NT-WeP8
Growth of Carbon with Vertically Aligned Nano-scale Flake Structure by rf Sputtering

Wednesday, November 5, 2003, 11:00 am, Room Hall A-C

Session: Poster Session
Presenter: E. Kusano, Kanazawa Institute of Technology, Japan
Authors: E. Kusano, Kanazawa Institute of Technology, Japan
H. Zhang, Kanazawa Institute of Technology, Japan
T. Kogure, University of Tokyo, Japan
I. Yoshimura, Kanazawa Institute of Technology, Japan
K. Yamamoto, Kanazawa Institute of Technology, Japan
A. Kinbara, Kanazawa Institute of Technology, Japan
Correspondent: Click to Email
Carbon nanoflake has been deposited by rf sputtering using the mixture of Ar and CH@sub 4@ with a total pressure of 14.5Pa as a discharge gas and a graphite disk as a target. A Si (110) wafer was used as a substrate on which carbon nanoflakes was grown at 670°C. The rf (13.56MHz) discharge power was kept 100W for all deposition. Deposition time was changed from 15 min to 3 hours. Microstructure of deposited carbon was investigated by Field Emission Scanning Electron Microscope (FESEM) and High Resolution Transmission Electron Microscope (HRTEM). Under the present conditions, high-density vertically aligned carbon nanoflakes with a thickness of about 30 nm were obtained. High intensity and symmetry of electron diffraction pattern indicated that carbon nanoflakes deposited by rf sputtering had the three dimensionally perfect crystallinity with an interlayer spacing of 335pm. In particular, there was no disorder in stacking of layer structure. It was further found that the thickness of the flakes was independent of deposition time while the length of the flakes increased to about 600-800 nm with increasing deposition time to 3 hours. Width of the carbon nanoflake was about 300 nm after 3-hour deposition. The results suggest that a critical thickness of carbon nanoflake exists, possibly depending on deposition conditions such as substrate temperature and discharge pressure. This critical thickness was almost equal to the layer number of about 90. Some potential applications of the carbon nanoflake film are being considered in vacuum electronic devices, chemical catalyst, frictional abrasion resistance, etc.