US3645292A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas supply system
Assignee: H L Schoger & Associates Inc
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Filing: 1970-07-23
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Granted: 1972-02-29
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Expires: 1990-07-23
Abstract
Abstract An improved gas supply system for supplying nitrogen and/or oxygen or other gases to semiconductor doping systems via liquid, such as water, boiling in a flask in a manner whereby the supply of gas remains consistent as to its characteristics, for example, moisture content, purity, etc. A double check valve arrangement, with one check valve weighted to a closed position, permits a gas, such as oxygen, to be supplied selectively wet or dry to a doping furnace as employed in semiconductor manufacture. The dual check valve arrangement further serves to permit a second source of gas to be employed. Liquid is maintained at a constant level in the boiling water flask by means of a magnetic element carried in the elongated stem of a float riding in the water. The magnetic element serves to activate a reed switch for electrically controlling a solenoid operated water supply valve.
Inventors
- 👤 Henry L Schoger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:40
CPC Classifications
C; C30; C30B; C30B31/00; C30B31/06; C30B31/16; C30B31/165; Y; Y10; Y10T; Y10T137/00; Y10T137/2931; Y10T137/3112; Y10T137/8593; Y10T137/87265; Y10T137/87338; Y10T137/87507
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
276 words
A gas supply system for doping semiconductor materials comprising a source of gas, a supply line leading from said source, a closed container adapted to receive water therein, means to supply and heat the water in the container, an output line forming a fluid discharge path from said container, a furnace input line adapted to carry gas into a semiconductor doping furnace, first and second check valves each oriented to pass fluid into said furnace input line and disposed whereby the discharge side of each check valve is coupled to supply gas under pressure to tend to close the discharge side of the other valve, means forming a first and second fluid path to said furnace input line from said source, said first path including said second check valve means and said second path including said container and said first check valve means, selectively operable gas supply valve means coupled to said gas supply line to selectively direct gas from said source to said furnace input line via said first or second path, a steam relief valve coupled to said second fluid path intermediate said first check valve means and said container and selectively operable to vent or contain steam pressure in said second path, and control means operably coupled to means for operating both said steam relief valve and said gas supply valve means and serving in one state to operate the steam relief valve to prevent pressure buildup in said second path when the gas supply valve means has been operated to couple said source to said first path and in a second state to reverse the conditions of the two last-named valve means.
Claim 2
Dependent Claim
276 words
A gas supply system for doping semiconductor materials comprising a source of gas, a supply line leading from said source, a closed container adapted to receive water therein, means to supply and heat the water in the container, an output line forming a fluid discharge path from said container, a furnace input line adapted to carry gas into a semiconductor doping furnace, first and second check valves each oriented to pass fluid into said furnace input line and disposed whereby the discharge side of each check valve is coupled to supply gas under pressure to tend to close the discharge side of the other valve, means forming a first and second fluid path to said furnace input line from said source, said first path including said second check valve means and said second path including said container and said first check valve means, selectively operable gas supply valve means coupled to said gas supply line to selectively direct gas from said source to said furnace input line via said first or second path, a steam relief valve coupled to said second fluid path intermediate said first check valve means and said container and selectively operable to vent or contain steam pressure in said second path, and control means operably coupled to means for operating both said steam relief valve and said gas supply valve means and serving in one state to operate the steam relief valve to prevent pressure buildup in said second path when the gas supply valve means has been operated to couple said source to said first path and in a second state to reverse the conditions of the two last-named valve means.
Claim 3
Dependent Claim
51 words
A gas supply system according to claim 1 in which there is further included a second source of gas and means serving to selectively couple same to said first path to be delivered to said furnace input line while said second gas urges said first check valve to a closed state.
Claim 4
Dependent Claim
55 words
A gas supply system according to claim 1 wherein each of said check valves includes a movable closure element, said closure element for said first check valve being characterized by means for urging same to a position impeding the flow passage of said first check valve in favor of that of said second check valve.
Claim 5
Dependent Claim
67 words
A gas supply system according to claim 3 wherein the last-named means comprises additional weight carried by said closure element of said first check valve as compared to that of the closure element of said second check valve, said valves being oriented to dispose their closure elements for movement between lowered and raised positions to respectively close and open a flow passage in their respective check valves.
Claim 6
Dependent Claim
147 words
In a system for supplying gas to an input line of a semiconductor furnace from a source of gas, first and second check valves, each of said check valves including a movable closure element, each check valve being oriented to pass gas to said Input line and disposed whereby the discharge side of each check valve is coupled to supply gas to the discharge side of the other for closing the flow passage thereof, the closure element for said first check valve being provided with means for urging same to a position closing the flow passage of said first check valve in favor of that of said second check valve whereby the pressure of gas fed to said input line via said second check valve plus the action of said means serves to protect said gas from being mixed with gas fed via said first check valve.
Claim 7
Dependent Claim
147 words
In a system for supplying gas to an input line of a semiconductor furnace from a source of gas, first and second check valves, each of said check valves including a movable closure element, each check valve being oriented to pass gas to said Input line and disposed whereby the discharge side of each check valve is coupled to supply gas to the discharge side of the other for closing the flow passage thereof, the closure element for said first check valve being provided with means for urging same to a position closing the flow passage of said first check valve in favor of that of said second check valve whereby the pressure of gas fed to said input line via said second check valve plus the action of said means serves to protect said gas from being mixed with gas fed via said first check valve.
Claim 8
Dependent Claim
54 words
In a system for supplying gas according to claim 5 wherein said means consists of a heavier closure element in said first check valve than in said second check valve, the closure elements of both of said check valves being oriented to require upward movement in order to pass gas through their respective valves.
Claim 9
Dependent Claim
67 words
In a system for supplying gas according to claim 1 further including a source of liquid for said container, float means riding in said liquid in said container, electrically operated valve means serving to selectively supply said liquid to said container, and switch means operably responsive to the position of said float means for operating said valve means in response to the liquid level within said container.
Claim 10
Dependent Claim
148 words
In a system according to claim 1 further including an elongated float element for riding deeply in liquid maintained in said container, electrically operated valve means serving to selectively supply liquid to said container, and switch means operably responsive to the position of said float element for operating said valve means in response to the liquid level within said container, said switch means including a pair of conductive movable leave including a portion of each disposed in closely spaced relation to the other, one of said leaves being nonmagnetic and the other being magnetically responsive, a magnet carried by said float element for movement into and out of proximity with said portions to attract said magnetically responsive leaf into engagement with the other leaf to close the switch, said valve means being operably responsive to closure of the switch to control the flow of liquid into said container.
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) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |