US4735633A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and system for vapor extraction from gases
Assignee: DRYSCRUB ETC A CALIFORNIA Corp
•
Filing: 1987-06-23
•
Granted: 1988-04-05
•
Expires: 2007-06-23
Abstract
Abstract Vapor phase waste species are removed from effluent gas streams using a plasma extraction reactor comprising a pair of parallel, spaced-apart electrodes. The electrodes are driven under conditions, usually at radio frequency, to induce a glow discharge in the waste species, and the excited species are deposited directly on the electrode surface. By providing a very high ratio of electrode area to reactor volume and waste gas volumetric flow rate, substantially complete removal of the waste species can be effected. The system is particularly useful in removing contaminant species discharged from semiconductor processing operations, such as chemical vapor deposition and plasma etching. The method and system are particularly advantageous in that the vapor phase waste products are converted to a solid phase deposited directly on the electrodes which may then be disposed of.
Inventors
- 👤 Kin-Chung R. Chiu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:41
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/32798; H01J37/32816; H01J37/32834; H01J37/32844; H01J37/32532; H01J37/32568; B; B01; B01D; B01D53/00; B01D53/32; B01D53/34; B01J; B01J19/00; B01J19/08; B01J19/087; B01J19/088; B03; B03C; B03C3/00; B03C3/34; B03C3/38; C; C23; C23C; C23C16/00; C23C16/44; C23C16/4412; B01J2219/00; B01J2219/08; B01J2219/0894
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
76 words
A method for extracting a vapor from an exhaust gas stream, said method comprising: passing the exhaust gas stream between opposed, parallel electrodes; and driving the electrodes under conditions selected to electronically excite the vapor and to cause substantially all of the excited vapor to react at the surface of the electrodes to deposit a stable film thereon whereby in excess of above 75 mole % of the vapor is extracted from the exhaust gas stream.
Claim 2
Independent Claim
76 words
A method for extracting a vapor from an exhaust gas stream, said method comprising: passing the exhaust gas stream between opposed, parallel electrodes; and driving the electrodes under conditions selected to electronically excite the vapor and to cause substantially all of the excited vapor to react at the surface of the electrodes to deposit a stable film thereon whereby in excess of above 75 mole % of the vapor is extracted from the exhaust gas stream.
Claim 3
Dependent Claim
19 words
A method as in claim 1, wherein the electrodes are replaced after the film thickness exceeds a predetermined amount.
Claim 4
Dependent Claim
18 words
A method as in claim 1, wherein the electrodes define a convoluted flow path for the exhaust stream.
Claim 5
Dependent Claim
14 words
A method as in claim 3, wherein the electrodes define a spiral flow path.
Claim 6
Dependent Claim
36 words
A method as in claim 3, wherein the electrodes comprise a first bank of parallel electrodes interleaved with a second bank of parallel electrodes to define a reversing serpentine path from the inlet to the outlet.
Claim 7
Dependent Claim
58 words
A plasma extraction reactor comprising: a vessel chamber defining an inlet port and an outlet port; spaced-apart, parallel electrodes located within the vessel and defining a convoluted flow path between said inlet and outlet ports; and means for driving the electrodes under conditions capable of electronically exciting a vapor species in an exhaust stream passing between the electrodes.
Claim 8
Dependent Claim
58 words
A plasma extraction reactor comprising: a vessel chamber defining an inlet port and an outlet port; spaced-apart, parallel electrodes located within the vessel and defining a convoluted flow path between said inlet and outlet ports; and means for driving the electrodes under conditions capable of electronically exciting a vapor species in an exhaust stream passing between the electrodes.
Claim 9
Dependent Claim
30 words
A plasma extraction reactor as in claim 6, wherein the electrodes comprise a pair of spaced-apart, parallel electrodes which define a spiral flow path from the inlet to the outlet.
Claim 10
Dependent Claim
38 words
A plasma extraction reactor as in claim 6, wherein the electrodes comprise a first bank of parallel electrodes interleaved with a second bank of parallel electrodes to define a reversing serpentine path from the inlet to the outlet.
Claim 11
Independent Claim
73 words
A method for extracting vapor species from an exhaust stream, said method comprising: passing the exhaust stream through a volume defined by opposed, parallel electrodes, wherein the ratio of the surface area of the electrodes to the volume therebetween is in excess of about 1 cm -1 ; and driving the electrodes under conditions selected to react at least about 75 mole % of the vapor species on the surface of the electrodes.
Claim 12
Independent Claim
73 words
A method for extracting vapor species from an exhaust stream, said method comprising: passing the exhaust stream through a volume defined by opposed, parallel electrodes, wherein the ratio of the surface area of the electrodes to the volume therebetween is in excess of about 1 cm -1 ; and driving the electrodes under conditions selected to react at least about 75 mole % of the vapor species on the surface of the electrodes.
Claim 13
Dependent Claim
22 words
A method as in claim 9, wherein the electrodes are replaced after a predetermined amount of the species have deposited on them.
Claim 14
Dependent Claim
18 words
A method as in claim 9, wherein the electrodes define a convoluted flow path for the exhaust stream.
Claim 15
Dependent Claim
14 words
A method as in claim 11, wherein the electrodes define a spiral flow path.
Claim 16
Dependent Claim
36 words
A method as in claim 11, wherein the electrodes comprise a first bank of parallel electrodes interleaved with a second bank of parallel electrodes to define a reversing serpentine path from the inlet to the outlet.
Claim 17
Dependent Claim
75 words
A plasma extraction reactor comprising: a vessel chamber defining an inlet port and an outlet port; spaced-apart, parallel electrodes located within the vessel and defining a flow path between said inlet and outlet ports, wherein the ratio of the surface area to the volume is at least about 1 cm -1 ; and means for driving the electrodes under conditions capable of electronically exciting a vapor species in an exhaust stream passing between the electrodes.
Claim 18
Dependent Claim
75 words
A plasma extraction reactor comprising: a vessel chamber defining an inlet port and an outlet port; spaced-apart, parallel electrodes located within the vessel and defining a flow path between said inlet and outlet ports, wherein the ratio of the surface area to the volume is at least about 1 cm -1 ; and means for driving the electrodes under conditions capable of electronically exciting a vapor species in an exhaust stream passing between the electrodes.
Claim 19
Dependent Claim
30 words
A plasma extraction reactor as in claim 14, wherein the electrodes comprise a pair of spaced-apart, parallel electrodes which define a spiral flow path from the inlet to the outlet.
Claim 20
Dependent Claim
38 words
A plasma extraction reactor as in claim 14, wherein the electrodes comprise a first bank of parallel electrodes interleaved with a second bank of parallel electrodes to define a reversing serpentine path from the inlet to the outlet.
Claim 21
Dependent Claim
24 words
A plasma extraction reactor as in claim 14, wherein the length of the flow path between the electrodes is at least about 100 cm.
Claim 22
Independent Claim
75 words
A method for extracting vapor species from an exhaust stream, said method comprising: passing the exhaust stream from an inlet to an outlet on a flow path defined by opposed, parallel electrodes, wherein said electrodes are arranged to intensify an electric field therebetween proximate the outlet end of the flow path; and driving the electrodes under conditions selected to deposit at least about 80 mole % of the species on the surface of the electrodes.
Claim 23
Independent Claim
75 words
A method for extracting vapor species from an exhaust stream, said method comprising: passing the exhaust stream from an inlet to an outlet on a flow path defined by opposed, parallel electrodes, wherein said electrodes are arranged to intensify an electric field therebetween proximate the outlet end of the flow path; and driving the electrodes under conditions selected to deposit at least about 80 mole % of the species on the surface of the electrodes.
Claim 24
Dependent Claim
22 words
A method as in claim 18, wherein the electrodes are replaced after a predetermined amount of the species have deposited on them.
Claim 25
Dependent Claim
18 words
A method as in claim 18, wherein the electrodes define a convoluted flow path for the exhaust stream.
Claim 26
Dependent Claim
14 words
A method as in claim 20, wherein the electrodes define a spiral flow path.
Claim 27
Dependent Claim
36 words
A method as in claim 20, wherein the electrodes comprise a first bank of parallel electrodes interleaved with a second bank of parallel electrodes to define a reversing serpentine path from the inlet to the outlet.
Claim 28
Dependent Claim
28 words
A method as in claim 18, wherein the ratio of the electrode area to the volumetric flow rate of the exhaust stream is at least about 10 min/cm.
Claim 29
Dependent Claim
70 words
A plasma extraction reactor comprising: a vessel chamber defining an inlet port and an outlet port; spaced-apart, parallel electrodes located within the vessel and defining a flow path between said inlet and outlet ports, wherein said electrodes are arranged to intensify an electric field therebetween proximate the outlet end of the flow path; and means for driving the electrodes under conditions capable of electronically exciting a vapor species passing therebetween.
Claim 30
Dependent Claim
70 words
A plasma extraction reactor comprising: a vessel chamber defining an inlet port and an outlet port; spaced-apart, parallel electrodes located within the vessel and defining a flow path between said inlet and outlet ports, wherein said electrodes are arranged to intensify an electric field therebetween proximate the outlet end of the flow path; and means for driving the electrodes under conditions capable of electronically exciting a vapor species passing therebetween.
Claim 31
Dependent Claim
30 words
A plasma extraction reactor as in claim 24, wherein the electrodes comprise a pair of spaced-apart, parallel electrodes which define a spiral flow path from the inlet to the outlet.
Claim 32
Dependent Claim
38 words
A plasma extraction reactor as in claim 24, wherein the electrodes comprise a first bank of parallel electrodes interleaved with a second bank of parallel electrodes to define a reversing serpentine path from the inlet to the outlet.
References Cited (Backward Citations)
US387286A
Cited
DE215706C
Cited
US1056026A
Cited
US1846365A
Cited
CH217221A
Cited
US3805492A
Cited
US3948625A
Cited
US3853512A
Cited
JPS51129868A
Cited
US4422407A
Cited
JPS584518A
Cited
JPS586231A
Cited
US4491606A
Cited
US4483883A
Cited
US4522674A
Cited
US4472174A
Cited
JPS60137421A
Cited
JPS60193522A
Cited
EP0158823A2
Cited
GB2158055A
Cited
EP0176295A2
Cited
US4664938A
Cited
US4626448A
Cited
US4675089A
Cited
JPH06108514A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-05 | 1991-10-05 | 1992-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-05 | 1995-10-05 | 1996-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-05 | 1999-10-05 | 2000-04-05 | $7700.00 | Window Closed / Lapsed |