US5325019A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control of plasma process by use of harmonic frequency components of voltage and current
Assignee: State University of New York Polytechnic Institute
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Filing: 1992-08-21
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Granted: 1994-06-28
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Expires: 2012-08-21
Abstract
Abstract The present invention provides for a technique for taking advantage of the intrinsic electrical non-linearity of processing plasmas to add additional control variables that affect process performance. The technique provides for the adjustment of the electrical coupling circuitry, as well as the electrical excitation level, in response to measurements of the reactor voltage and current and to use that capability to modify the plasma characteristics to obtain the desired performance.
Inventors
- 👤 Paul A. Miller
- 👤 Mattan Kamon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:30
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32917; H01J37/3299; H01J37/32009; H01J37/32082; H01J37/32174; H01J37/32183; H01J2237/00; H01J2237/32; H01J2237/33; H01J2237/334
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
158 words
In a plasma processing apparatus, having a reactor for processing a plasma gas and wherein said reactor is coupled to an electrical energy source for generating an electrical signal at a fundamental frequency f in order to provide an electrical energy field for generation of plasma and wherein a non-linear response of said plasma introduces harmonic frequency components of voltage and current of said electrical signal, such that an operating characteristic of said plasma is measurable by observing voltage and current values of said electrical signal at its fundamental frequency and said harmonic frequency components, a combination of said reactor and a variable impedance device coupled between said reactor and said electrical energy source for selecting an operating point of said plasma by adjusting an impedance of said variable impedance device until a desirable electrical operating point of said plasma is selected based on one or more of said fundamental and harmonic frequency components of voltage and current.
Claim 2
Dependent Claim
158 words
In a plasma processing apparatus, having a reactor for processing a plasma gas and wherein said reactor is coupled to an electrical energy source for generating an electrical signal at a fundamental frequency f in order to provide an electrical energy field for generation of plasma and wherein a non-linear response of said plasma introduces harmonic frequency components of voltage and current of said electrical signal, such that an operating characteristic of said plasma is measurable by observing voltage and current values of said electrical signal at its fundamental frequency and said harmonic frequency components, a combination of said reactor and a variable impedance device coupled between said reactor and said electrical energy source for selecting an operating point of said plasma by adjusting an impedance of said variable impedance device until a desirable electrical operating point of said plasma is selected based on one or more of said fundamental and harmonic frequency components of voltage and current.
Claim 3
Dependent Claim
26 words
The apparatus of claim 1 wherein a dc bias voltage from said electrical energy source is observed and utilized to obtain said desirable electrical operating point.
Claim 4
Dependent Claim
40 words
The apparatus of claim 1 wherein said variable impedance device adjusts an effective electrical length of a conductor coupled between said variable impedance device and said reactor in order to vary said impedance to select said desirable electrical operating point.
Claim 5
Dependent Claim
27 words
The apparatus of claim 1 wherein said variable impedance device includes a variable capacitor in order to vary said impedance to select said desirable electrical operating point.
Claim 6
Dependent Claim
158 words
A plasma processing apparatus for processing a plasma gas and in which said apparatus is coupled to an electrical energy source for generating an electrical signal at a fundamental frequency f in order to provide an electrical energy field for generation of plasma and wherein a non-linear response of said plasma introduces harmonic frequency components of voltage and current of said electrical signal, such that an operating characteristic of said plasma is measurable by observing voltage and current values of said electrical signal at its fundamental frequency and said harmonic frequency components comprising: a reactor for processing said plasma gas therein; a variable impedance device coupled between said reactor and said electrical energy source for selecting an operating point of said plasma by adjusting an impedance of said variable impedance device until a desirable electrical operating point of said plasma is selected based on one or more of said fundamental and harmonic frequency components of voltage and current.
Claim 7
Dependent Claim
158 words
A plasma processing apparatus for processing a plasma gas and in which said apparatus is coupled to an electrical energy source for generating an electrical signal at a fundamental frequency f in order to provide an electrical energy field for generation of plasma and wherein a non-linear response of said plasma introduces harmonic frequency components of voltage and current of said electrical signal, such that an operating characteristic of said plasma is measurable by observing voltage and current values of said electrical signal at its fundamental frequency and said harmonic frequency components comprising: a reactor for processing said plasma gas therein; a variable impedance device coupled between said reactor and said electrical energy source for selecting an operating point of said plasma by adjusting an impedance of said variable impedance device until a desirable electrical operating point of said plasma is selected based on one or more of said fundamental and harmonic frequency components of voltage and current.
Claim 8
Dependent Claim
26 words
The apparatus of claim 5 wherein a dc bias voltage from said electrical energy source is observed and utilized to obtain said desirable electrical operating point.
Claim 9
Dependent Claim
40 words
The apparatus of claim 5 wherein said variable impedance device adjusts an effective electrical length of a conductor coupled between said variable impedance device and said reactor in order to vary said impedance to select said desirable electrical operating point.
Claim 10
Dependent Claim
27 words
The apparatus of claim 5 wherein said variable impedance device includes a variable capacitor in order to vary said impedance to select said desirable electrical operating point.
Claim 11
Independent Claim
163 words
A method for processing a semiconductor material by utilizing a plasma process of exposing said semiconductor material to a plasma gas in a reactor wherein said reactor is coupled to an electrical energy source for generating an electrical signal at a fundamental frequency f in order to provide an electrical energy field for generation of plasma and wherein a non-linear response of said plasma introduces harmonic frequency components of voltage and current of said electrical signal, such that an operating characteristic of said plasma is measurable by observing voltage and current values of said electrical signal at its fundamental frequency and said harmonic frequency components comprising: inserting a variable impedance device between said reactor and said electrical energy source to select an operating point of said plasma by adjusting an impedance of said variable impedance device until a desirable electrical operating point of said plasma is selected based on one or more of said fundamental and harmonic frequency components of voltage and current.
Claim 12
Independent Claim
163 words
A method for processing a semiconductor material by utilizing a plasma process of exposing said semiconductor material to a plasma gas in a reactor wherein said reactor is coupled to an electrical energy source for generating an electrical signal at a fundamental frequency f in order to provide an electrical energy field for generation of plasma and wherein a non-linear response of said plasma introduces harmonic frequency components of voltage and current of said electrical signal, such that an operating characteristic of said plasma is measurable by observing voltage and current values of said electrical signal at its fundamental frequency and said harmonic frequency components comprising: inserting a variable impedance device between said reactor and said electrical energy source to select an operating point of said plasma by adjusting an impedance of said variable impedance device until a desirable electrical operating point of said plasma is selected based on one or more of said fundamental and harmonic frequency components of voltage and current.
Claim 13
Dependent Claim
26 words
The method of claim 9 wherein a dc bias voltage from said electrical energy source is observed and utilized to obtain said desirable electrical operating point.
Claim 14
Dependent Claim
40 words
The method of claim 9 wherein said variable impedance device adjusts an effective electrical length of a conductor coupled between said variable impedance device and said reactor in order to vary said impedance to select said desirable electrical operating point.
Claim 15
Dependent Claim
27 words
The method of claim 9 wherein said variable impedance device includes a variable capacitor in order to vary said impedance to select said desirable electrical operating point.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-06-27 | 1997-12-27 | 1998-06-28 | $2000.00 | Window Closed / Lapsed |
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