abstract |
In an apparatus for the reactive coating of a substrate (1) with an electrically conductive material (FIG. 1 ), for example with silicon dioxide (SiO2), including a power source (10) which is connected with a cathode (5) disposed in an evacuable coating chamber (15, 15a) and enclosing magnets (7, 8, 9) and which cooperates electrically with a target (3) which is sputtered and whose sputtered particles deposit themselves on the substrate, two electrodes (5, 44) separated electrically from one another and from the sputtering chamber (25) are provided, the one electrode (5) being a magnetron cathode in which the cathode body (11) and the material of the target (3) are connected electrically with one another and the other electrode acts as an anode (44) in the plasma discharge, and wherein a direct-current source (10) with an electrically floating output is provided whose negative terminal is connected with the cathode (5)-with the interposition of choke (45) and resistance (46) connected parallel to the latter-and whose positive terminal is connected by the line (40) to the anode (44), and wherein, for the purpose of a stable coating process, between the cathode (5) and the anode (44) a first low-inductance, RF-compatible capacitor (34) and an inductor (49) are inserted and between anode (44) and the electrically separated vacuum chamber (25) a resistor (47) is inserted. |