摘要 |
Sputtering cathode (1) according to the magnetron principle, having a target (11) of the material to be sputtered, which consists of at least one piece. Behind the target (11) there is a magnet system with a plurality of endless magnet units (14, 15, 16) of alternately different polarity, one inside the other. An endless magnetic tunnel (20) of arcuately curved lines of force is thereby formed. Those poles of the magnet units (14, 15, 16) which are turned away from the target (11) are connected together through a magnet yoke (19) of soft magnetic material. To achieve an especially good target utilization, the geometry and the amount of the magnetic field forming a magnetic tunnel (20) are variable relative to the magnetic field strength of another magnetic field through an electromagnetic (17), the current for the electromagnet (17) being variable in frequency, amplitude and pulse shape.
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