AVS 46th International Symposium
    Thin Films Division Friday Sessions
       Session TF-FrM

Paper TF-FrM9
Stabilization of High Deposition Rate Reactive Magnetron Sputtering of Oxides by In-Situ Spectroscopic Ellipsometry and Plasma Diagnostics

Friday, October 29, 1999, 11:00 am, Room 615

Session: In-situ Characterization and Material Process Imaging
Presenter: M. Vergöhl, Fraunhofer Institute for Surface Engineering and Thin Films, Germany
Authors: M. Vergöhl, Fraunhofer Institute for Surface Engineering and Thin Films, Germany
N. Malkomes, Fraunhofer Institute for Surface Engineering and Thin Films, Germany
B. Hunsche, Fraunhofer Institute for Surface Engineering and Thin Films, Germany
B. Szyszka, Fraunhofer Institute for Surface Engineering and Thin Films, Germany
T. Matthée, Fraunhofer Institute for Surface Engineering and Thin Films, Germany
Correspondent: Click to Email
High deposition rates are of essential importance in reactive magnetron sputtering on architectural glass. To reach high deposition rates and a high transparency of oxide films with constant properties during the full target lifetime, it is required that the process can be stabilized in a specific window within the transition mode. In general, the control of the plasma parameters alone (i.e. partial pressure, optical emission intensity, plasma impedance) is not sufficient for the definition of an operating point with constant film parameters. Therefore, a control system is proposed that is based on a combination of a short-term stabilization of the plasma and a long-term stabilization employing an in-situ spectroscopic ellipsometer. For niobium and titanium oxide, both an optical emission monitor and reactive gas partial pressure measurement were employed. In addition, it turns out that the specific deposition rate, i.e. deposition rate divided by the power density, is a suitable control parameter. Compared to the oxide mode, the deposition rate of Nb2O5 and TiO2 films deposited in the transition mode could be enlarged by a factor of 3-4. The films were grown at different process parameters (oxygen partial pressure, target power, absolute pressure, mid-frequency and DC-technique) onto unheated substrates. Nearby in-situ ellipsometry, ex-situ spectroscopic ellipsometry at different angles of incidence was applied to study the optical properties and the morphology of the films.