Plasma generator

Claim 3

A method for generating an electrical plasma in accordance with claim 1 wherein the potential between said first and said second electrodes is only slightly more than said breakdown potential and step C further comprises the steps of: C'. maintaining the potential of said vessel relative to said reference potential at a value substantially halfway between said first potential and said second potential so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 4

Apparatus for generating an electrical plasma in a plasma processing system for processing work pieces within a vacuum vessel, said system having at least two electrodes for generating a plasma, said apparatus comprising, first power supply means for establishing a first electrical potential with respect to a reference potential on a first one of said electrodes, second power supply means establishing a second electrical potential with respect to a reference potential on a second one of said electrodes, the difference between the value of said first potential and the value of said second potential exceeding the breakdown potential in said vessel, and third power supply means for maintaining the potential of said vessel relative to said reference potential at a value between said first potential and said second potential so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 5

Apparatus for generating an electrical plasma in a plasma processing system for processing work pieces within a vacuum vessel, said system having at least two electrodes for generating a plasma, said apparatus comprising, first power supply means for establishing a first electrical potential with respect to a reference potential on a first one of said electrodes, second power supply means establishing a second electrical potential with respect to a reference potential on a second one of said electrodes, the difference between the value of said first potential and the value of said second potential exceeding the breakdown potential in said vessel, and third power supply means for maintaining the potential of said vessel relative to said reference potential at a value between said first potential and said second potential so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 6

Apparatus for generating an electrical plasma in accordance with claim 3 wherein the potential between said first and said second electrodes is only slightly more than said breakdown potential and said third power supply means maintains the potential of said vessel relative to said reference potential at a value substantially halfway between said first potential and said second potential so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 7

Apparatus for generating an electrical plasma in accordance with claim 3 wherein said first electrode and said second electrode are curved to shape said plasma.

Claim 8

Apparatus for generating an electrical plasma in accordance with claim 3 wherein said processing system includes more than three or more electrodes.

Claim 9

Apparatus for generating an electrical plasma in accordance with claim 3 further comprising fourth power supply means for maintaining at least one of said work pieces at a fourth potential relative to said reference potential.

Claim 10

Apparatus for generating an electrical plasma in accordance with claim 3 wherein said first and second power supply means are alternating current power supplies.

Claim 11

Apparatus for generating an electrical plasma in a plasma processing system for processing work pieces within a vacuum vessel, said system having at least two electrodes for generating a plasma, said apparatus comprising, power supply means for establishing an first electrical potential with respect to a reference potential on a first one of said electrodes, said first potential exceeding the breakdown potential in said vessel, first means for dividing said first potential down to generate a second electrical potential with respect to a reference potential on a second one of said electrodes, the difference between the value of said first potential and the value of said second potential exceeding the breakdown potential in said vessel, and second means for dividing said first potential down to generate a third potential on said vessel relative to said reference potential at a value between said first potential and said second potential so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 12

Apparatus for generating an electrical plasma in a plasma processing system for processing work pieces within a vacuum vessel, said system having at least two electrodes for generating a plasma, said apparatus comprising, power supply means for establishing an first electrical potential with respect to a reference potential on a first one of said electrodes, said first potential exceeding the breakdown potential in said vessel, first means for dividing said first potential down to generate a second electrical potential with respect to a reference potential on a second one of said electrodes, the difference between the value of said first potential and the value of said second potential exceeding the breakdown potential in said vessel, and second means for dividing said first potential down to generate a third potential on said vessel relative to said reference potential at a value between said first potential and said second potential so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 13

Apparatus for generating an electrical plasma in accordance with claim 9 wherein the potential between said first and said second electrodes is only slightly more than said breakdown potential and second dividing means maintains the potential of said vessel relative to said reference potential at a value halfway between said first potential and said second potential so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 14

Apparatus for generating an electrical plasma in accordance with claim 9 wherein said first electrode and said second electrode are curved to shape said plasma.

Claim 15

Apparatus for generating an electrical plasma in accordance with claim 9 wherein said processing system includes more than three or more electrodes.

Claim 16

Apparatus for generating an electrical plasma in accordance with claim 9 further comprising a second power supply means for maintaining at least one of said work pieces at a fourth potential relative to said reference potential.

Claim 17

Apparatus for generating an electrical plasma in accordance with claim 9 wherein said first and second power supply means are alternating current power supplies.

Claim 18

Apparatus for generating an electrical plasma in a plasma processing system for processing work pieces within a vacuum vessel, said system having at least two electrodes for generating said plasma, said apparatus comprising, a transformer having a tapped secondary winding, said transformer generating across its secondary winding a first electrical potential exceeding the breakdown potential in said vessel, first means for attaching one of said electrodes to one end of said secondary winding, second means for attaching another of said electrodes to the other end of said secondary winding, third means for attaching said vessel to said tap so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 19

Apparatus for generating an electrical plasma in a plasma processing system for processing work pieces within a vacuum vessel, said system having at least two electrodes for generating said plasma, said apparatus comprising, a transformer having a tapped secondary winding, said transformer generating across its secondary winding a first electrical potential exceeding the breakdown potential in said vessel, first means for attaching one of said electrodes to one end of said secondary winding, second means for attaching another of said electrodes to the other end of said secondary winding, third means for attaching said vessel to said tap so that the electrical potential between said vessel and said electrodes is less than said breakdown potential.

Claim 20

Apparatus for generating an electrical plasma in accordance with claim 15 wherein said tap is a center tap.

Claim 21

Apparatus for generating an electrical plasma in accordance with claim 15 wherein said processing system includes more than three or more electrodes.

Claim 22

Apparatus for generating an electrical plasma in accordance with claim 15 further comprising a power supply for maintaining at least one of said work pieces at a potential relative to said vessel.