AVS 50th International Symposium
    Advanced Surface Engineering Monday Sessions
       Session SE-MoA

Invited Paper SE-MoA3
Reactive Magnetron Sputtering of Hard Si-C-N and Si-B-C-N Films and Their Properties

Monday, November 3, 2003, 2:40 pm, Room 323

Session: Hard Coatings: Preparation, Properties, Wear, and Nanotribology
Presenter: J. Vlcek, University of West Bohemia, Czech Republic
Authors: J. Vlcek, University of West Bohemia, Czech Republic
J. Cizek, University of West Bohemia, Czech Republic
S. Potocky, University of West Bohemia, Czech Republic
M. Kormunda, University of West Bohemia, Czech Republic
J. Houska, University of West Bohemia, Czech Republic
P. Zeman, University of West Bohemia, Czech Republic
Z. Soukup, University of West Bohemia, Czech Republic
Correspondent: Click to Email
Based on the results obtained for C-N films a systematic investigation of reactive magnetron sputtering of hard ternary Si-C-N and quaternary Si-B-C-N materials has been carried out. The Si-C-N and Si-B-C-N films were deposited on Si(100) substrates by dc magnetron co-sputtering of silicon and carbon (Si-C-N films) and silicon, boron and carbon (Si-B-C-N films) in nitrogen-argon gas mixtures using a composed C-Si and C-Si-B (at a fixed 20% boron fraction in the erosion track area) target, respectively, with variable Si/C area ratios. Elemental compositions of the films (determined by RBS and ERD), their bonding structure, and mechanical (hardness and friction coefficient) and optical (refractive index and extinction coefficient) properties were controlled by the Si fraction (5-80%) in the magnetron erosion track area, by the Ar concentration (0-75%) in the gas mixture, by the rf induced negative substrate bias voltage (from a floating potential to -500V) and by the substrate temperature (135-800°C). The total pressure and the discharge current on the magnetron target were held constant at 0.5Pa and 1A, respectively. The energy and flux of ions bombarding the target and the growing films were estimated on the basis of the discharge characteristics measured for both the dc magnetron discharge and the rf discharge dominating in a deposition zone. Mass spectroscopy was used to explain differences between sputtering of carbon, boron and silicon from the composed targets in nitrogen-argon discharges. The films, typically 1-2µm thick, were found to be amorphous with a very smooth surface (R@sub a@ less than 1nm) and good adhesion to substrates at a compressive stress less than 1.2GPa. They exhibited hardness up to 35GPa (Si-C-N films) and 50GPa (Si-B-C-N films), enhanced high-temperature oxidation resistance and very high optical transparency (at a high Si content), and promising tribological properties (at a high C content).