US6853142B2 — Methods and apparatus for generating high-density…

Claim 1

Independent Claim 119 words

An apparatus for generating a strongly-ionized plasma in a chamber, the apparatus comprising: an ionization source that generates a weakly-ionized plasma from a feed gas, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition in the chamber; a power supply that supplies power to the weakly-ionized plasma though an electrical pulse applied across the weakly-ionized plasma, the electrical pulse having a magnitude and a rise-time that is sufficient to increase the density of the weakly-ionized plasma to generate a strongly-ionized plasma; and a gas line that supplies feed gas to the strongly-ionized plasma, the feed gas diffusing the strongly-ionized plasma, thereby allowing additional power from the pulsed power supply to be absorbed by the strongly-ionized plasma.

Claim 2

Independent Claim 119 words

An apparatus for generating a strongly-ionized plasma in a chamber, the apparatus comprising: an ionization source that generates a weakly-ionized plasma from a feed gas, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition in the chamber; a power supply that supplies power to the weakly-ionized plasma though an electrical pulse applied across the weakly-ionized plasma, the electrical pulse having a magnitude and a rise-time that is sufficient to increase the density of the weakly-ionized plasma to generate a strongly-ionized plasma; and a gas line that supplies feed gas to the strongly-ionized plasma, the feed gas diffusing the strongly-ionized plasma, thereby allowing additional power from the pulsed power supply to be absorbed by the strongly-ionized plasma.

Claim 3

Dependent Claim 41 words

The apparatus of claim 1 wherein the power supply applies the electrical pulse across the weakly-ionized plasma to excite atoms in the weakly-ionized plasma and to generate secondary electrons, the secondary electrons ionizing the excited atoms, thereby creating the strongly-ionized plasma.

Claim 4

Dependent Claim 24 words

The apparatus of claim 1 wherein the gas line supplies additional feed gas that exchanges the weakly-ionized plasma while applying the electrical pulse across.

Claim 5

Dependent Claim 13 words

The apparatus of claim 1 wherein the power supply generates a constant power.

Claim 6

Dependent Claim 13 words

The apparatus of claim 1 wherein the power supply generates a constant voltage.

Claim 7

Dependent Claim 60 words

The apparatus of claim 1 wherein the ionization source is chosen from the group comprising an electrode coupled to a DC power supply, an electrode coupled to an AC power supply, a UV source, an X-ray source, an electron beam source, an ion beam source, an inductively coupled plasma source, a capacitively coupled plasma source, and a microwave plasma source.

Claim 8

Dependent Claim 31 words

The apparatus of claim 1 further comprising a magnet that is positioned to generate a magnetic field proximate to the weakly-ionized plasma, the magnetic field trapping electrons in the weakly-ionized plasma.

Claim 9

Dependent Claim 11 words

The apparatus of claim 7 wherein the magnet comprises an electro-magnet.

Claim 10

Dependent Claim 10 words

The apparatus of claim 7 wherein the magnet is movable.

Claim 11

Independent Claim 97 words

A method for generating a strongly-ionized plasma in a chamber, the method comprising: ionizing a feed gas to form a weakly-ionized plasma that reduces the probability of developing an electrical breakdown condition in the chamber; supplying power to the weakly-ionized plasma by applying an electrical pulse across the weakly-ionized plasma, the electrical pulse having a magnitude and a rise-time that is sufficient to increase the density of the weakly-ionized plasma to generate a strongly-ionized plasma; and diffusing the strongly-ionized plasma with additional feed gas thereby allowing the strongly-ionized plasma to absorb additional energy from the power supply.

Claim 12

Independent Claim 97 words

A method for generating a strongly-ionized plasma in a chamber, the method comprising: ionizing a feed gas to form a weakly-ionized plasma that reduces the probability of developing an electrical breakdown condition in the chamber; supplying power to the weakly-ionized plasma by applying an electrical pulse across the weakly-ionized plasma, the electrical pulse having a magnitude and a rise-time that is sufficient to increase the density of the weakly-ionized plasma to generate a strongly-ionized plasma; and diffusing the strongly-ionized plasma with additional feed gas thereby allowing the strongly-ionized plasma to absorb additional energy from the power supply.

Claim 13

Dependent Claim 37 words

The method of claim 10 wherein the applying the electrical pulse across the weakly-ionized plasma excites atoms in the weakly-ionized plasma and generates secondary electrons, the secondary electrons ionizing the excited atoms, thereby creating a strongly-ionized plasma.

Claim 14

Dependent Claim 15 words

The method of claim 10 further comprising exchanging the weakly-ionized plasma with additional feed gas.

Claim 15

Dependent Claim 21 words

The method of claim 10 wherein the applying the electrical pulse comprises applying a quasi-static electric field across the weakly-ionized plasma.

Claim 16

Dependent Claim 34 words

The method of claim 10 further comprising selecting at least one of a pulse amplitude and a pulse width of the electrical pulse in order to increase an ionization rate of the strongly-ionized plasma.

Claim 17

Dependent Claim 34 words

The method of claim 10 further comprising selecting at least one of a pulse amplitude and a pulse width of the electrical pulse in order to cause the strongly-ionized plasma to be substantially uniform.

Claim 18

Dependent Claim 19 words

The method of claim 10 wherein the electrical pulse comprises a rise time that is less than about 100V/μsec.

Claim 19

Dependent Claim 23 words

The method of claim 10 wherein the peak plasma density of the weakly-ionized plasma is less than about 10 12 cm −3 .

Claim 20

Dependent Claim 23 words

The method of claim 10 wherein the peak plasma density of the strongly-ionized plasma is greater than about 10 12 cm −3 .

Claim 21

Dependent Claim 38 words

The method of claim 10 wherein the ionizing the feed gas comprises exposing the feed gas to one of a static electric field, an pulsed electric field, UV radiation, X-ray radiation, electron beam radiation, and an ion beam.

Claim 22

Dependent Claim 25 words

The method of claim 10 further comprising generating a magnetic field proximate to the weakly-ionized plasma, the magnetic field trapping electrons in the weakly-ionized plasma.

Claim 23

Independent Claim 98 words

An apparatus for generating a strongly-ionized plasma, the apparatus comprising: an anode; a cathode that is positioned adjacent to the anode and forming a gap there between; an ionization source that generates a weakly-ionized plasma proximate to the cathode, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition between the anode and the cathode; and a power supply that produces an electric field across the gap, the electric field generating excited atoms in the weakly-ionized plasma and generating secondary electrons from the cathode, the secondary electrons ionizing the excited atoms, thereby creating the strongly-ionized plasma.

Claim 24

Independent Claim 98 words

An apparatus for generating a strongly-ionized plasma, the apparatus comprising: an anode; a cathode that is positioned adjacent to the anode and forming a gap there between; an ionization source that generates a weakly-ionized plasma proximate to the cathode, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition between the anode and the cathode; and a power supply that produces an electric field across the gap, the electric field generating excited atoms in the weakly-ionized plasma and generating secondary electrons from the cathode, the secondary electrons ionizing the excited atoms, thereby creating the strongly-ionized plasma.

Claim 25

Dependent Claim 13 words

The apparatus of claim 21 wherein the power supply generates a constant power.

Claim 26

Dependent Claim 13 words

The apparatus of claim 21 wherein the power supply generates a constant voltage.

Claim 27

Dependent Claim 14 words

The apparatus of claim 21 wherein the electric field comprises a quasi-static electric field.

Claim 28

Dependent Claim 14 words

The apparatus of claim 21 wherein the electric field comprises a pulsed electric field.

Claim 29

Dependent Claim 28 words

The apparatus of claim 21 wherein a rise time of the electric field is chosen to increase an ionization rate of the excited atoms in the weakly-ionized plasma.

Claim 30

Dependent Claim 16 words

The apparatus of claim 21 wherein the strongly-ionized plasma is substantially uniform proximate to the cathode.

Claim 31

Dependent Claim 32 words

The apparatus of claim 21 wherein a dimension of the gap between the anode and the cathode is chosen to increase an ionization rate of the excited atoms in the weakly-ionized plasma.

Claim 32

Dependent Claim 60 words

The apparatus of claim 21 wherein the ionization source is chosen from the group comprising an electrode coupled to a DC power supply, an electrode coupled to an AC power supply, a UV source, an X-ray source, an electron beam source, an ion beam source, an inductively coupled plasma source, a capacitively coupled plasma source, and a microwave plasma source.

Claim 33

Dependent Claim 35 words

The apparatus of claim 21 further comprising a magnet that is positioned to generate a magnetic field proximate to the weakly-ionized plasma, the magnetic field trapping electrons in the weakly-ionized plasma proximate to the cathode.

Claim 34

Independent Claim 77 words

A method for generating a strongly-ionized plasma, the method comprising: ionizing a feed gas to generate a weakly-ionized plasma proximate to a cathode, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition proximate to the cathode; and applying an electric field across the weakly-ionized plasma in order to excite atoms in the weakly-ionized plasma and to generate secondary electrons from the cathode, the secondary electrons ionizing the excited atoms, thereby creating the strongly-ionized plasma.

Claim 35

Independent Claim 77 words

A method for generating a strongly-ionized plasma, the method comprising: ionizing a feed gas to generate a weakly-ionized plasma proximate to a cathode, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition proximate to the cathode; and applying an electric field across the weakly-ionized plasma in order to excite atoms in the weakly-ionized plasma and to generate secondary electrons from the cathode, the secondary electrons ionizing the excited atoms, thereby creating the strongly-ionized plasma.

Claim 36

Dependent Claim 17 words

The method of claim 31 wherein the applying the electric field comprises applying a quasi-static electric field.

Claim 37

Dependent Claim 20 words

The method of claim 31 wherein the applying an electric field comprises applying the electric field at a constant power.

Claim 38

Dependent Claim 20 words

The method of claim 31 wherein the applying an electric field comprises applying the electric field at a constant voltage.

Claim 39

Dependent Claim 20 words

The method of claim 31 wherein the applying the electric field comprises applying an electrical pulse across the weakly-ionized plasma.

Claim 40

Dependent Claim 34 words

The method of claim 35 further comprising selecting at least one of a pulse amplitude and a pulse width of the electrical pulse in order to increase an ionization rate of the strongly-ionized plasma.

Claim 41

Dependent Claim 44 words

The method of claim 35 further comprising selecting at least one of a pulse amplitude and a pulse width of the electrical pulse in order to cause the strongly-ionized plasma to be substantially uniform in an area adjacent to a surface of the cathode.

Claim 42

Dependent Claim 16 words

The method of claim 31 wherein the strongly-ionized plasma is substantially uniform proximate to the cathode.

Claim 43

Dependent Claim 25 words

The method of claim 31 further comprising generating a magnetic field proximate to the weakly-ionized plasma, the magnetic field trapping electrons in the weakly-ionized plasma.

Claim 44

Independent Claim 101 words

An apparatus for generating a strongly-ionized plasma in a chamber, the apparatus comprising: means for ionizing a feed gas to form a weakly-ionized plasma that reduces the probability of developing an electrical breakdown condition in the chamber; means for supplying power to the weakly-ionized plasma by applying an electrical pulse across the weakly-ionized plasma, the electrical pulse having a magnitude and a rise-time that is sufficient to increase the density of the weakly-ionized plasma to generate a strongly-ionized plasma; and means for diffusing the strongly-ionized plasma with additional feed gas to allow additional power to be absorbed by the strongly-ionized plasme.

Claim 45

Independent Claim 101 words

An apparatus for generating a strongly-ionized plasma in a chamber, the apparatus comprising: means for ionizing a feed gas to form a weakly-ionized plasma that reduces the probability of developing an electrical breakdown condition in the chamber; means for supplying power to the weakly-ionized plasma by applying an electrical pulse across the weakly-ionized plasma, the electrical pulse having a magnitude and a rise-time that is sufficient to increase the density of the weakly-ionized plasma to generate a strongly-ionized plasma; and means for diffusing the strongly-ionized plasma with additional feed gas to allow additional power to be absorbed by the strongly-ionized plasme.

Claim 46

Independent Claim 81 words

An apparatus for generating a strongly-ionized plasma, the apparatus comprising: means for ionizing a feed gas to generate a weakly-ionized plasma proximate to a cathode, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition proximate to the cathode; and means for applying an electric field across the weakly-ionized plasma in order to excite atoms in the weakly-ionized plasma and to generate secondary electrons from the cathode, the secondary electrons ionizing the excited atoms, thereby creating the strongly-ionized plasma.

Claim 47

Independent Claim 81 words

An apparatus for generating a strongly-ionized plasma, the apparatus comprising: means for ionizing a feed gas to generate a weakly-ionized plasma proximate to a cathode, the weakly-ionized plasma reducing the probability of developing an electrical breakdown condition proximate to the cathode; and means for applying an electric field across the weakly-ionized plasma in order to excite atoms in the weakly-ionized plasma and to generate secondary electrons from the cathode, the secondary electrons ionizing the excited atoms, thereby creating the strongly-ionized plasma.

Claim 48

Dependent Claim 13 words

The apparatus of claim 1 wherein the power supply comprises the ionization source.

Claim 49

Dependent Claim 13 words

The apparatus of claim 21 wherein the power supply comprises the ionization source.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2008-02-08	2008-08-09	2009-02-08	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2012-02-08	2012-08-09	2013-02-08	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2016-02-08	2016-08-09	2017-02-08	$7700.00	Window Closed / Lapsed

Methods and apparatus for generating high-density plasma

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