Discharge characteristics of magnetron cells with different lengths in ultrahigh vacuum

Institute of Surface Engineering and Optoelectronics, Teslova 30, 1000 Ljubljana, Slovenia
Vacuum (Impact Factor: 1.53). 01/2003; DOI: 10.1016/S0042-207X(02)00741-8

ABSTRACT Discharge characteristics of several magnetron cells have been measured at different experimental conditions. The cell diameter was always 27 mm, while the length was between 13 and 50 mm. The voltage was varied between 1 and 8 kV. The magnetic field and pressure were constant at 0.13 T and 1×10−8 mbar, respectively. The maximum current through the cell was found to be a strong function of the cell length. A maximum was observed at the cell length of about 20 mm followed by a minimum at about 35 mm. The behaviour was explained by variations in the space charge formed within the discharge volume.

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