US4723254A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recycling apparatus for an excimer laser
Assignee: Individual
•
Filing: 1985-05-22
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Granted: 1988-02-02
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Expires: 2005-05-22
Abstract
Abstract For an excimer laser system utilizing in a laser chamber a lasing material and a mixture of a diluent rare gas and a heavy rare gas and halogen rare gas in given percentages, there is disclosed a method and apparatus for reducing the expenditure of the rare gases by continuously evacuating the laser mixture from the laser chamber removing from the evacuated laser mixture any gaseous impurities to provide a cleaned laser mixture and thereafter feeding the cleaned laser mixture back into the laser chamber. Along with the cleaned laser mixture there is fed in a supplemental halogen gas. The gaseous impurities along with the halogen are removed by passing the gas through an elongated tube having calcium particles therein with a void fraction for a given length of tube in the range 0.30 to 0.60. Some of the ratio is obtained by providing alternate layers of calcium particles and inert, refractory spacers, such as stainless steel wool.
Inventors
- 👤 Robert E. Turner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:21
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/02; H01S3/03; H01S3/036; H01S3/14; H01S3/22; H01S3/223; H01S3/225
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
82 words
Apparatus for removing chemical impurities from a rare gas stream comprising an elongated tubular member of given volume having an inlet for accepting the rare gas stream and an outlet for passing the rare gas stream and calcium particles of given volume within said tubular member, the quotient of the empty volume of the tubular member to the volume of calcium particles in said tubular member for a given length of said tubular member being in the range of 0.03 to 0.60.
Claim 2
Dependent Claim
82 words
Apparatus for removing chemical impurities from a rare gas stream comprising an elongated tubular member of given volume having an inlet for accepting the rare gas stream and an outlet for passing the rare gas stream and calcium particles of given volume within said tubular member, the quotient of the empty volume of the tubular member to the volume of calcium particles in said tubular member for a given length of said tubular member being in the range of 0.03 to 0.60.
Claim 3
Dependent Claim
31 words
The apparatus of claim 1 wherein said calcium particles have a size of 2 to 4 mesh and the inner diameter of said tubular member being from 0.75 to 2.00 inches.
Claim 4
Dependent Claim
31 words
The apparatus of claim 1 wherein said calcium particles occupy only a portion of said given length and further comprising inert, refractory spacer means in the remainder of said given length.
Claim 5
Dependent Claim
35 words
The apparatus of claim 3 wherein there is at least two layers of calcium particles and said inert spacer means is a layer of a metal wool interposed between the two layers of calcium particles.
Claim 6
Dependent Claim
31 words
The apparatus of claim 4 wherein the ratio of the length of a layer of calcium particles to a layer of metal wool being in the range of 1.5 to 5.
Claim 7
Dependent Claim
34 words
The apparatus of claim 1 wherein said elongated tubular member is of a refractory material and further means for heating said calcium particles to a temperature in the range of 500° to 700° C.
Claim 8
Dependent Claim
54 words
The apparatus of claim 1 wherein said calcium particles are arranged within said tubular member in a plurality of axially displaced layers and further comprising a plurality of layers of stainless steel wool, the layers of stainless steel wool axially alternating with the layers of calcium particles along the length of said tubular member.
Claim 9
Dependent Claim
31 words
The apparatus of claim 7 wherein the ratio of the length of a layer of calcium particles to a layer of metal wool being in the range of 1.5 to 5.0.
Claim 10
Dependent Claim
31 words
The apparatus of claim 8 wherein said calcium particles have a size of 2 to 4 mesh and the inner diameter of said tubular member being from 0.75 to 2.00 inches.
Claim 11
Dependent Claim
34 words
The apparatus of claim 9 wherein said elongated tubular member is of a refractory material and further means for heating said calcium particles to a temperature in the range of 500° to 700° C.
Claim 12
Dependent Claim
55 words
Apparatus for removing chemical impurities from a rare gas stream comprising an elongated tubular member having an inlet and an outlet, at least two layers of particles of calcium and at least one layer of metal spacers between said two layers of particles of calcium, said layers being axially aligned within said elongated tubular member.
Claim 13
Dependent Claim
55 words
Apparatus for removing chemical impurities from a rare gas stream comprising an elongated tubular member having an inlet and an outlet, at least two layers of particles of calcium and at least one layer of metal spacers between said two layers of particles of calcium, said layers being axially aligned within said elongated tubular member.
Claim 14
Dependent Claim
31 words
The apparatus of claim 11 wherein said calcium particles have a size of 2 to 4 mesh and the inner diameter of said tubular member being from 0.75 to 2.00 inches.
Claim 15
Dependent Claim
31 words
The apparatus of claim 12 wherein the ratio of the length of a layer of calcium particles to a layer of metal wool being in the range of 1.5 to 5.0.
Claim 16
Dependent Claim
34 words
The apparatus of claim 13 wherein said elongated tubular member is of a refractory material and further means for heating said calcium particles to a temperature in the range of 500° to 700° C.
Claim 17
Dependent Claim
165 words
Apparatus for conserving the expenditure of diluent rare gas and heavy rare gas in an excimer laser system utilizing in a laser chamber a mixture of the diluent rare gas, the heavy rare gas and a halogen, said apparatus comprising: withdrawing means for continuously withdrawing the gas mixture from the lasing chamber; cleaning means for removing halogen compounds from the withdrawn gas mixture, said cleaning means comprising an elongated tubular member of given volume having an inlet for accepting the rare gas stream and an outlet for passing the rare gas stream and calcium particles of given volume within said tubular member, the quotient of the empty volume of tubular member to the volume of calcium particles in said tubular member for a given length of said tubular member being in the range of 0.30 to 0.60; means for returning the cleaned gas mixture back to the lasing chamber; and means for adding to the mixture another gas mixture comprising at least the halogen gas.
Claim 18
Dependent Claim
165 words
Apparatus for conserving the expenditure of diluent rare gas and heavy rare gas in an excimer laser system utilizing in a laser chamber a mixture of the diluent rare gas, the heavy rare gas and a halogen, said apparatus comprising: withdrawing means for continuously withdrawing the gas mixture from the lasing chamber; cleaning means for removing halogen compounds from the withdrawn gas mixture, said cleaning means comprising an elongated tubular member of given volume having an inlet for accepting the rare gas stream and an outlet for passing the rare gas stream and calcium particles of given volume within said tubular member, the quotient of the empty volume of tubular member to the volume of calcium particles in said tubular member for a given length of said tubular member being in the range of 0.30 to 0.60; means for returning the cleaned gas mixture back to the lasing chamber; and means for adding to the mixture another gas mixture comprising at least the halogen gas.
Claim 19
Dependent Claim
31 words
The apparatus of claim 15 wherein said calcium particles have a size of 2 to 4 mesh and the inner diameter of said tubular member being from 0.75 to 2.00 inches.
Claim 20
Dependent Claim
30 words
The apparatus of claim 15 wherein said calcium particles occupy only a portion of said given length and further comprising metal spacer means in the remainder of said given length.
Claim 21
Dependent Claim
34 words
The apparatus of claim 17 wherein there are at least two layers of calcium particles and said metal spacer means is a layer of metal wool interposed between the two layers of calcium particles.
Claim 22
Dependent Claim
35 words
The apparatus of claim 15 wherein said elongated tubular member is of a refractory material and further comprising means for heating said calcium particles to a temperature in the range of 500° to 700° C.
Claim 23
Dependent Claim
54 words
The apparatus of claim 15 wherein said calcium particles are arranged within said tubular member in a plurality of axially displaced layers and further comprising a plurality of layers of stainless steel wool, the layers of stainless steel wool axially alternating with the layers of calcium particles along the length of said tubular member.
References Cited (Backward Citations)
US4196400A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-01 | 1991-08-03 | 1992-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-01 | 1995-08-03 | 1996-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-01 | 1999-08-03 | 2000-02-02 | $7700.00 | Window Closed / Lapsed |