Open AccessUltrahard Multilayer Coatings
Author(s) -
D. C. Chrzan,
M.T. Dugger,
D. M. Follstaedt,
Lawrence H. Friedman,
T. A. Friedmann,
J. A. Knapp,
Kevin F. McCarty,
Douglas L. Medlin,
Paul B. Mirkarimi,
Nancy A. Missert,
P.P. Newcomer,
John P. Sullivan,
D. R. Tallant
Publication year - 1999
Language(s) - English
Resource type - Reports
DOI - 10.2172/7225
Subject(s) - materials science , diamond , annealing (glass) , composite material , thin film , modulus , pulsed laser deposition , atmospheric temperature range , optoelectronics , nanotechnology , physics , meteorology
We have developed a new multilayer a-tC material that is thick stress-free, adherent, low friction, and with hardness and stiffness near that of diamond. The new a-tC material is deposited by J pulsed-laser deposition (PLD) at room temperature, and fully stress-relieved by a short thermal anneal at 600°C. A thick multilayer is built up by repeated deposition and annealing steps. We measured 88 GPa hardness, 1100 GPa Young's modulus, and 0.1 friction coefficient (under high load). Significantly, these results are all well within the range reported for crystalline diamond. In fact, this material, if considered separate from crystalline diamond, is the 2nd hardest material known to man. Stress-free a-tC also has important advantages over thin film diamond; namely, it is smooth, processed at lower temperature, and can be grown on a much broader range of substrates. This breakthrough will enable a host of applications that we are actively pursuing in MEMs, sensors, LIGA, etc