Apparatus and method for nano plasma deposition
An apparatus and method for initiation and control of a sustained metal plasma and nano plasma (macroparticulate) deposition methods for preparing modified metal coatings are provided. The plasma deposition process can be tightly controlled by virtue of a device that incorporates a plasma arc initiator component and an internal power supply that is capable of controlling dwell time on the target and the size range of particles ejected in the plasma arc.
1. A power supply control unit, comprising:
a plasma arc initiator device, wherein the plasma arc initiator device comprises:
a solid state relay having one end connected to a positive terminal of the DC power supply;
a resistor having a first end coupled to a second end of the solid state relay and a second end coupled to a negative terminal of the DC power supply, wherein when the solid state relay is in a closed position a short circuit occurs in a signal path of the solid state relay, the resistor and the DC power supply; and
a cathode formed at the negative terminal of the DC power supply and electrically connected to the negative terminal of the DC power supply;
a plurality of insulated Gate Bipolar Transistors (IGBTs), wherein a collector of each of the plurality of IGBTs is coupled to a DC power supply and an emitter of each of the plurality of IGBTs is coupled to a corresponding output for outputting power from the DC power supply; and
at least one control circuit, wherein one of the at least one control circuit is coupled to a gate of a corresponding one or more of the plurality of IGBTs,
wherein the at least one control circuit controls the corresponding one or more of the plurality of IGBTs to switch power supplied from the DC power supply from being output from one of the plurality of IGBTs to be output from another of the plurality of IGBTs.
2. The power supply control unit of claim 1 , wherein the plasma arc initiator further comprises an anode at the positive side of the DC power supply and separated a predetermined distance from the cathode.
3. The power supply control unit of claim 2 , wherein the plasma are initiator cathode provides a point of contact on a target.
4. The power supply control unit of claim 3 , wherein the plasma arc initiator point of contact consists of one or more conductive materials.
5. The power supply control unit of claim 1 , wherein the plasma arc initiator further comprises:
a material having a resistance, wherein the material has a first end coupled to the positive side of the DC power supply and a second end coupled to the negative side of the DC power supply.
6. The power supply control unit of claim 5 , wherein the resistance of the plasma arc initiator material is slightly greater than or equal to a resistance of plasma formed between the cathode and an anode formed at the positive side of the DC power supply and separated a predetermined distance from the cathode.
7. The power supply control unit of claim 1 , wherein the corresponding outputs of the plurality of IGBTs are connected to the cathode, wherein the plurality of IGBTs output the power from the DC power supply to the cathode according to a control signal from the at least one control circuit.
8. The power supply control unit of claim 1 , further comprising:
a cold plate coupled with a respective one of the at least one IGBT.
9. The power supply control unit of claim 1 , wherein the DC power supply is capable of supplying a current up to 600 A and a DC voltage up to 20 V.
10. The power supply control unit of claim 1 , wherein the at least one control circuit is a single control circuit coupled to all of the at least one IGBT.
11. The power supply control unit of claim 1 , wherein each of the at least one control circuit is coupled to a corresponding one of the at least one IGBT.