US6150628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Toroidal low-field reactive gas source
Assignee: MKS Instruments Inc
•
Filing: 1997-06-26
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Granted: 2000-11-21
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Expires: 2017-06-26
Abstract
Abstract An apparatus for dissociating gases includes a plasma chamber that may be formed from a metallic material and a transformer having a magnetic core surrounding a portion of the plasma chamber and having a primarily winding. The apparatus also includes one or more switching semiconductor devices that are directly coupled to a voltage supply and that have an output coupled to the primary winding of the transformer. The one or more switching semiconductor devices drive current in the primary winding that induces a potential inside the chamber that forms a plasma which completes a secondary circuit of the transformer.
Inventors
- 👤 Donald K. Smith
- 👤 Xing Chen
- 👤 William M. Holber
- 👤 Eric Georgelis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:31
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J27/00; H01J27/02; H01J27/16; H01J37/32082; H01J37/321; H01J37/32357; H01J37/32431; H01J37/32798; H01J37/32853; H01J37/32862
Claims Analysis
Total Claims: 50
Claim 1
Independent Claim
91 words
An apparatus for dissociating gases comprising: a) a plasma chamber; b) a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) a solid state AC switching power supply comprising one or more switching semiconductor devices coupled to a voltage supply and having an output coupled to the primary winding, the AC switching power supply driving current in the primary winding, the current inducing an AC potential inside the chamber that directly forms a toroidal plasma which completes a secondary circuit of the transformer.
Claim 2
Independent Claim
91 words
An apparatus for dissociating gases comprising: a) a plasma chamber; b) a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) a solid state AC switching power supply comprising one or more switching semiconductor devices coupled to a voltage supply and having an output coupled to the primary winding, the AC switching power supply driving current in the primary winding, the current inducing an AC potential inside the chamber that directly forms a toroidal plasma which completes a secondary circuit of the transformer.
Claim 3
Dependent Claim
19 words
The apparatus of claim 1 wherein the voltage supply comprises a line voltage supply or a bus voltage supply.
Claim 4
Dependent Claim
19 words
The apparatus of claim 1 wherein the one or more switching semiconductor devices comprises one or more switching transistors.
Claim 5
Dependent Claim
23 words
The apparatus of claim 1 wherein the output of the one or more switching semiconductor devices is directly coupled to the primary winding.
Claim 6
Dependent Claim
12 words
The apparatus of claim 1 wherein the chamber comprises a metallic material.
Claim 7
Dependent Claim
11 words
The apparatus of claim 5 wherein the metallic material comprises aluminum.
Claim 8
Dependent Claim
12 words
The apparatus of claim 1 wherein the chamber comprises a dielectric material.
Claim 9
Dependent Claim
27 words
The apparatus of claim 1 further comprising an electrode positioned in the chamber that generates free charges which assist the ignition of a plasma in the chamber.
Claim 10
Dependent Claim
28 words
The apparatus of claim 1 further comprising an electrode capacitively coupled to the chamber that generates free charges which assist the ignition of a plasma in the chamber.
Claim 11
Dependent Claim
30 words
The apparatus of claim 1 further comprising an ultraviolet light source optically coupled to the chamber that generates free charges which assist the ignition of a plasma in the chamber.
Claim 12
Dependent Claim
58 words
The apparatus of claim 1 further comprising a circuit for measuring electrical parameters of the primary winding and the plasma, the electrical parameters including one or more of a current driving the primary winding, a voltage across the primary winding, a bus voltage, an average power in the primary winding, and a peak power in the primary winding.
Claim 13
Dependent Claim
66 words
The apparatus of claim 11 further comprising a power control circuit coupled to an output of the circuit for measuring electrical parameters of the primary winding and the plasma, the power control circuit determining the current driving the primary winding from a measurement of the electrical properties of the primary winding and of the plasma and from a predetermined set point representing a desired operating condition.
Claim 14
Dependent Claim
27 words
The apparatus of claim 1 further comprising a process chamber that is coupled to the plasma chamber and positioned to receive reactive gas generated by the plasma.
Claim 15
Independent Claim
108 words
An apparatus for generating ions comprising: a) a plasma chamber; b) a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) a solid state AC switching power supply comprising one or more switching semiconductor devices coupled to a voltage supply and having an output coupled to the primary winding, the solid state AC switching power supply driving current in the primary winding, the current inducing an AC potential inside the chamber that directly forms a toroidal plasma which completes a secondary circuit of the transformer, and d) an orifice positioned in the chamber for directing ions generated by the plasma.
Claim 16
Independent Claim
108 words
An apparatus for generating ions comprising: a) a plasma chamber; b) a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) a solid state AC switching power supply comprising one or more switching semiconductor devices coupled to a voltage supply and having an output coupled to the primary winding, the solid state AC switching power supply driving current in the primary winding, the current inducing an AC potential inside the chamber that directly forms a toroidal plasma which completes a secondary circuit of the transformer, and d) an orifice positioned in the chamber for directing ions generated by the plasma.
Claim 17
Dependent Claim
19 words
The apparatus of claim 14 wherein the voltage supply comprises a line voltage supply or a bus voltage supply.
Claim 18
Dependent Claim
29 words
The apparatus of claim 14 further comprising a process chamber that is coupled to the orifice in the Plasma chamber and adapted to receive ions generated by the plasma.
Claim 19
Dependent Claim
21 words
The apparatus of claim 16 further comprising accelerating electrodes positioned in the process chamber for accelerating ions generated by the plasma.
Claim 20
Dependent Claim
12 words
The apparatus of claim 14 wherein the chamber comprises a refractory metal.
Claim 21
Independent Claim
93 words
An apparatus for dissociating gases comprising: a) a plasma chamber comprising an electrically conductive material and at least one dielectric region that forms an electrical discontinuity in the chamber; b) a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) an AC power supply having an output electrically connected to the primary winding, the power supply driving current in the primary winding, the current inducing an AC potential inside the chamber that directly forms a toroidal plasma which completes a secondary circuit of the transformer.
Claim 22
Independent Claim
93 words
An apparatus for dissociating gases comprising: a) a plasma chamber comprising an electrically conductive material and at least one dielectric region that forms an electrical discontinuity in the chamber; b) a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) an AC power supply having an output electrically connected to the primary winding, the power supply driving current in the primary winding, the current inducing an AC potential inside the chamber that directly forms a toroidal plasma which completes a secondary circuit of the transformer.
Claim 23
Dependent Claim
23 words
The apparatus of claim 19 wherein the chamber comprises a plurality of dielectric regions separating at least two regions of the plasma chamber.
Claim 24
Dependent Claim
30 words
The apparatus of claim 19 wherein the dielectric region comprises at least one of a dielectric spacer or a dielectric coating of at least one mating surface of the chamber.
Claim 25
Dependent Claim
10 words
The apparatus of claim 19 wherein the chamber comprises aluminum.
Claim 26
Dependent Claim
22 words
The apparatus of claim 19 wherein the chamber comprises cooling channels for passing a fluid that controls the temperature of the chamber.
Claim 27
Dependent Claim
31 words
The apparatus of claim 19 wherein the power supply comprises one or more switching semiconductor devices directly coupled to a voltage supply and having an output coupled to the primary winding.
Claim 28
Dependent Claim
19 words
The apparatus of claim 24 wherein the voltage supply comprises a line voltage supply or a bus voltage supply.
Claim 29
Dependent Claim
27 words
The apparatus of claim 19 further comprising an electrode positioned in the chamber that generates free charges which assist the ignition of a plasma in the chamber.
Claim 30
Dependent Claim
28 words
The apparatus of claim 19 further comprising an electrode capacitively coupled to the chamber that generates free charges which assist the ignition of a plasma in the chamber.
Claim 31
Dependent Claim
26 words
The apparatus of claim 19 further comprising an ultraviolet light source optically coupled to the chamber which assists the ignition of a plasma in the chamber.
Claim 32
Independent Claim
94 words
A method for dissociating gases comprising: a) providing a chamber for containing a gas at a pressure; b) providing a transformer having a magnetic core surrounding a portion of the chamber and a primary winding; c) driving the primary winding of the transformer with a current generated by a solid state AC switching power supply comprising one or more switching semiconductor devices; and d) inducing an AC potential inside the chamber with the current in the primary winding, the AC potential directly forming a toroidal plasma which completes a secondary circuit of the transformer.
Claim 33
Independent Claim
94 words
A method for dissociating gases comprising: a) providing a chamber for containing a gas at a pressure; b) providing a transformer having a magnetic core surrounding a portion of the chamber and a primary winding; c) driving the primary winding of the transformer with a current generated by a solid state AC switching power supply comprising one or more switching semiconductor devices; and d) inducing an AC potential inside the chamber with the current in the primary winding, the AC potential directly forming a toroidal plasma which completes a secondary circuit of the transformer.
Claim 34
Dependent Claim
42 words
The method of claim 29 wherein the step of directly coupling one or more switching semiconductor devices to a voltage supply comprises directly coupling the one or more switching semiconductor devices to a line voltage supply or to a bus voltage supply.
Claim 35
Dependent Claim
23 words
The method of claim 29 further comprising the step of directly coupling the one or more switching semiconductor devices to the primary winding.
Claim 36
Dependent Claim
18 words
The method of claim 29 further comprising the step of providing an initial ionization event in the chamber.
Claim 37
Dependent Claim
26 words
The method of claim 32 wherein the step of providing an initial ionization event in the chamber comprises applying a voltage pulse to the primary winding.
Claim 38
Dependent Claim
24 words
The method of claim 32 wherein the step of providing an initial ionization event in the chamber comprises exposing the chamber to ultraviolet light.
Claim 39
Dependent Claim
12 words
The method of claim 29 wherein the gas comprises a noble gas.
Claim 40
Dependent Claim
12 words
The method of claim 29 wherein the gas comprises a reactive gas.
Claim 41
Dependent Claim
19 words
The method of claim 29 wherein the gas comprises a mixture of a reactive gas and a noble gas.
Claim 42
Dependent Claim
56 words
The method of claim 29 further comprising the step of measuring electrical parameters of the primary winding and of the plasma including one or more of the current driving the primary winding, a voltage across the primary winding, a bus voltage, an average power in the primary winding, and a peak power in the primary winding.
Claim 43
Dependent Claim
47 words
The method of claim 37 further comprising the step of determining an output of the one or more switching semiconductor devices from the measurement of the electrical parameters of the primary winding and of the plasma and from a predetermined set point representing a desired operating condition.
Claim 44
Dependent Claim
16 words
The method of claim 29 wherein the pressure is substantially between 1 mtorr and 100 torr.
Claim 45
Dependent Claim
17 words
The method of claim 29 wherein an electric field of the plasma is substantially between 1-100 V/cm.
Claim 46
Independent Claim
130 words
A method for cleaning a process chamber comprising: a) providing a plasma chamber for containing a reactive gas at a pressure, the plasma chamber being coupled to the process chamber; b) providing a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) driving the primary winding of the transformer with a current generated by a solid state AC switching power supply comprising one or more switching semiconductor devices; d) inducing an AC potential inside the plasma chamber with the current in the primary winding, the AC potential directly forming a plasma which completes a secondary circuit of the transformer; and e) directing chemically active species generated in the plasma from the plasma chamber into the process chamber thereby cleaning the process chamber.
Claim 47
Independent Claim
130 words
A method for cleaning a process chamber comprising: a) providing a plasma chamber for containing a reactive gas at a pressure, the plasma chamber being coupled to the process chamber; b) providing a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) driving the primary winding of the transformer with a current generated by a solid state AC switching power supply comprising one or more switching semiconductor devices; d) inducing an AC potential inside the plasma chamber with the current in the primary winding, the AC potential directly forming a plasma which completes a secondary circuit of the transformer; and e) directing chemically active species generated in the plasma from the plasma chamber into the process chamber thereby cleaning the process chamber.
Claim 48
Dependent Claim
20 words
The method of claim 42 wherein the current driving the primary winding corresponds to a power of approximately 3.5 kW.
Claim 49
Independent Claim
104 words
A method for generating reactive gases comprising: a) providing a plasma chamber for containing a reactive gas at a pressure; b) providing a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) driving the primary winding of the transformer with a current generated by a solid state AC switching power supply comprising one or more switching semiconductor devices; d) inducing an AC potential inside the chamber with the current in the primary winding, the AC potential directly forming a plasma which completes a secondary circuit of the transformer; and e) generating reactive gas in the plasma.
Claim 50
Independent Claim
104 words
A method for generating reactive gases comprising: a) providing a plasma chamber for containing a reactive gas at a pressure; b) providing a transformer having a magnetic core surrounding a portion of the plasma chamber and a primary winding; c) driving the primary winding of the transformer with a current generated by a solid state AC switching power supply comprising one or more switching semiconductor devices; d) inducing an AC potential inside the chamber with the current in the primary winding, the AC potential directly forming a plasma which completes a secondary circuit of the transformer; and e) generating reactive gas in the plasma.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-11-21 | 2004-05-22 | 2004-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-11-21 | 2008-05-22 | 2008-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-11-21 | 2012-05-22 | 2012-11-21 | $7700.00 | Window Closed / Lapsed |