A cathodic arc plasma source has an anode formed of a plurality of spaced baffles which extend beyond the active cathode surface of the cathode. With the open baffle structure of the anode, most macroparticles pass through the gaps between the baffles and reflect off the baffles out of the plasma stream that enters a filter. Thus the anode not only has an electrical function but serves as a prefilter. The cathode has a small diameter, e.g. a rod of about 1/4 inch (6.25 mm) diameter. Thus the plasma source output is well localized, even with cathode spot movement which is limited in area, so that it effectively couples into a miniaturized filter. With a small area cathode, the material eroded from the cathode needs to be replaced to maintain plasma production. Therefore, the source includes a cathode advancement or feed mechanism coupled to cathode rod. The cathode also requires a cooling mechanism. The movable cathode rod is housed in a cooled metal shield or tube which serves as both a current conductor, thus reducing ohmic heat produced in the cathode, and as the heat sink for heat generated at or near the cathode. Cooling of the cathode housing tube is done by contact with coolant at a place remote from the active cathode surface. The source is operated in pulsed mode at relatively high currents, about 1 kA. The high arc current can also be used to operate the magnetic filter. A cathodic arc plasma deposition system using this source can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.
RELATED APPLICATIONS
This application claims priority of Provisional Application Ser. No. 60/127,200 filed Mar. 31, 1999, which is herein incorporated by reference.
An ion source is provided, which generates or emits an ion beam which may be used to deposit a layer on a substrate, or the perform other functions. The ion source includes at least one anode and at least one cathode. In certain example embodiments, the cathode(s) is maintained or kept at a reference potential(s) other than ground for at least a period of time. This may be done, for example and without limitation, by electrically connecting a zener diode (single or double type, for example), thyristor (actively), or the like to the cathode. Thus, the ion source can be made so that it does not react adversely to its environment, and/or undesirable arcing between the anode and cathode can be reduced thereby improving ion source operation.
A device and a method for generating a truly pulsed plasma flow are disclosed. The device includes a cathode assembly comprising a cathode and a cathode holder, an anode, and two or more intermediate electrodes, the anode and the intermediate electrodes forming a plasma channel expanding toward the anode. The intermediate electrode closest to the cathode may form a plasma chamber around the cathode tip. An extension nozzle forming an extension channel having a tubular insulator along at least a portion of its interior surface is affixed to the anode end of the device.During operation, a voltage is applied between the cathode and the anode and a current is passed through the cathode, the plasma, and the anode. The voltage and current profiles are selected to cause the rapid development of a plasma flow with required characteristics. A substantially uniform temperature and power density distribution of the plasma pulse is achieved in the extension nozzle. Additionally, ozone may be generated in the extension nozzle during the generation of the plasma pulse.
