Verfahren und Schaltung zur bipolaren pulsfoermigen Energieeinspeisung in Niederdruckplasmen
The invention solves the problem of supplying the highest possible power over mean time to the low-pressure discharge. The same power shall be supplied in each pole, although the impedance differs strongly. In a system for plasma and surface technology comprising at least two electrodes and one power supply, the outputs of at least two floating direct current power supplies are switched in such a way that the output of the one DC power supply is connected to an identical polarity and the output of the other is connected conductively. These switches are operated by means of a clock generator at the rate of the pole changing frequency via a switch connected with each feeder line to the electrodes, and whose other outputs are routed together to the other outputs of the DC power source. When an arc discharge occurs, the switches are opened. The process is used for bipolar pulse sputtering to deposit electrically insulating layers on workpieces. Preferably, such layers are used for mechanic al protection, wear protection and to improve slide characteristics.
DE 1994-4438463 A: 19941027