Patent US4585516A successfully refreshed from Google Patents.
US4585516A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable duty cycle, multiple frequency, plasma reactor
Assignee: Motorola Solutions Inc
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Filing: 1985-03-04
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Granted: 1986-04-29
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Expires: 2005-03-04
Abstract
Abstract A plasma reactor and a process for operating a plasma reactor are disclosed. The reactor comprises parallel plates in which one plate is connected to a source of high frequency signal and a second plate is connected to a source of low frequency signal. Control apparatus modulates one or both signals. In the process, the duty cycles of the modulating signals is controlled so that the signals overlap during at least a portion of their cycles.
Inventors
- 👤 Glenn R. Corn
- 👤 Andreas G. Hegedus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:28
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32082; H01J37/32137; H01J37/32155; H01J37/32165
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
86 words
Plasma reactor apparatus comprising: first, second and third electrodes defining an enclosed volume for receiving an article to be treated; a source of high frequency signal; a source of low frequency signal; and means for selectively connecting said source of high frequency signal to one electrode and said source of low frequency signal to another electrode; said means comprising control means for modulating the amplitude of said signals so that at least one of said signals has a duty cycle of less than one hundred percent.
Claim 2
Dependent Claim
86 words
Plasma reactor apparatus comprising: first, second and third electrodes defining an enclosed volume for receiving an article to be treated; a source of high frequency signal; a source of low frequency signal; and means for selectively connecting said source of high frequency signal to one electrode and said source of low frequency signal to another electrode; said means comprising control means for modulating the amplitude of said signals so that at least one of said signals has a duty cycle of less than one hundred percent.
Claim 3
Dependent Claim
36 words
Plasma reactor apparatus at set forth in claim 1 wherein said means comprises control means for modulating both of said signals so that said signals each have a duty cycle of less than one hundred percent.
Claim 4
Dependent Claim
63 words
A process for treating semiconductor wafers in a plasma reactor comprising the steps of: applying a high frequency signal to a plasma reactor chamber; applying a low frequency signal to said plasma reactor chamber; supplying a reactant gas to said chamber; and modulating at least one of said signals so that the duty cycle of the signal is less than one hundred percent.
Claim 5
Dependent Claim
63 words
A process for treating semiconductor wafers in a plasma reactor comprising the steps of: applying a high frequency signal to a plasma reactor chamber; applying a low frequency signal to said plasma reactor chamber; supplying a reactant gas to said chamber; and modulating at least one of said signals so that the duty cycle of the signal is less than one hundred percent.
Claim 6
Dependent Claim
15 words
The process as set forth in claim 3 wherein both of said signals are modulated.
Claim 7
Dependent Claim
20 words
The process as set forth in claim 4 wherein said signals are modulated by modulating signals having the same frequency.
Claim 8
Dependent Claim
16 words
The process as set forth in claim 5 wherein said modulating signals have different duty cycles.
Claim 9
Dependent Claim
30 words
The process as set forth in claim 6 wherein said modulating signals have duty cycles such that high and low frequency signals are not simultaneously turned off during said process.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-28 | 1989-10-28 | 1990-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-28 | 1993-10-28 | 1994-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-28 | 1997-10-28 | 1998-04-29 | $7700.00 | Window Closed / Lapsed |