Patent US4994888A successfully refreshed from Google Patents.
Patent US5755934A successfully refreshed from Google Patents.
US5755934A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Point-of-use ammonia purification for electronic component manufacture
Assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Filing: 1996-03-04
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Granted: 1998-05-26
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Expires: 2016-03-04
Abstract
Abstract Highly purified ammonia for use in processes for the production of high-precision electronic components is prepared on-site by drawing ammonia vapor from a liquid ammonia reservoir, passing the vapor through a filter capable of filtering out particles of less than 0.005 micron in size, and scrubbing the filtered vapor in a high-pH aqueous scrubber.
Inventors
- 👤 Joe G. Hoffman
- 👤 R. Scot Clark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:29
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0402; H10P72/0404; C; C01; C01B; C01B7/00; C01B7/01; C01B7/07; C01B7/0706; C01B7/0712; C01B7/0731; C01B7/19; C01B7/191; C01B7/195; C01B7/196; C01B7/197; C01B7/198; C01C; C01C1/00; C01C1/02; C01C1/024; C01C1/16; C01C1/162; Y; Y10; Y10S; Y10S203/00; Y10S203/17
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
95 words
A system for the preparation of ultra-high purity ammonia, said system comprising: (a) a reservoir of liquid ammonia with a vapor space above said liquid ammonia; (b) means for drawing vapor containing ammonia gas from said vapor space; (c) a filtration membrane removing particles greater than 0.005 micron from vapor thus drawn; (d) a scrubber arranged to contact filtered vapor having passed through said filtration membrane with an aqueous solution of ammonia in deionized water, the vapor thus scrubbed being purified ammonia gas; and (e) piping for removing said purified ammonia gas from said scrubber.
Claim 2
Independent Claim
95 words
A system for the preparation of ultra-high purity ammonia, said system comprising: (a) a reservoir of liquid ammonia with a vapor space above said liquid ammonia; (b) means for drawing vapor containing ammonia gas from said vapor space; (c) a filtration membrane removing particles greater than 0.005 micron from vapor thus drawn; (d) a scrubber arranged to contact filtered vapor having passed through said filtration membrane with an aqueous solution of ammonia in deionized water, the vapor thus scrubbed being purified ammonia gas; and (e) piping for removing said purified ammonia gas from said scrubber.
Claim 3
Dependent Claim
129 words
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity reagents comprising ammonia to a semiconductor manufacturing operation, comprising: an evaporation source connected to receive a liquid ammonia source and to provide a flow of ammonia vapor therefrom; said flow of ammonia vapor being connected to pass through a unit which provides a recirculating volume of high-purity water, containing a high concentration of ammonium hydroxide, in contact with said flow of ammonia vapor; and a generator, connected to receive said flow of ammonia vapor from said unit and to combine said ammonia vapor with an aqueous liquid to produce an ultra-pure aqueous solution comprising ammonia; and a piping connection which routes said aqueous solution to at least one point of use in the semiconductor device fabrication facility.
Claim 4
Dependent Claim
129 words
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity reagents comprising ammonia to a semiconductor manufacturing operation, comprising: an evaporation source connected to receive a liquid ammonia source and to provide a flow of ammonia vapor therefrom; said flow of ammonia vapor being connected to pass through a unit which provides a recirculating volume of high-purity water, containing a high concentration of ammonium hydroxide, in contact with said flow of ammonia vapor; and a generator, connected to receive said flow of ammonia vapor from said unit and to combine said ammonia vapor with an aqueous liquid to produce an ultra-pure aqueous solution comprising ammonia; and a piping connection which routes said aqueous solution to at least one point of use in the semiconductor device fabrication facility.
Claim 5
Dependent Claim
18 words
The system of claim 2, further comprising a particulate filter interposed between said evaporation source and said unit.
Claim 6
Dependent Claim
14 words
The system of claim 2, wherein said liquid ammonia source consists of anhydrous ammonia.
Claim 7
Dependent Claim
17 words
The system of claim 2, wherein said recirculating volume of high-purity water does not contain any additives.
Claim 8
Dependent Claim
15 words
The system of claim 2, wherein said liquid ammonia source is of standard commercial-grade purity.
Claim 9
Dependent Claim
13 words
The system of claim 2, wherein said evaporator is a bulk storage tank.
Claim 10
Dependent Claim
25 words
The system of claim 2, wherein said evaporator operates at a controlled temperature, and is connected to receive liquid ammonia from a bulk storage tank.
Claim 11
Dependent Claim
132 words
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity reagents comprising ammonia to a semiconductor manufacturing operation, comprising: an evaporation source connected to receive a liquid ammonia and to provide a flow of ammonia vapor therefrom; said flow of ammonia vapor being connected to pass through a unit which provides a recirculating volume of high-purity water, containing a high concentration of ammonium hydroxide, in contact with said flow of ammonia vapor; and a generator, connected to receive said flow of ammonia vapor from said unit and to combine said ammonia vapor with an aqueous liquid to produce an ultra-pure aqueous solution comprising ammonia; whereby said ultra-pure aqueous solution can be used within the semiconductor device fabrication facility without bulk transfer or exposure of liquid surface to any uncontrolled atmosphere.
Claim 12
Dependent Claim
132 words
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity reagents comprising ammonia to a semiconductor manufacturing operation, comprising: an evaporation source connected to receive a liquid ammonia and to provide a flow of ammonia vapor therefrom; said flow of ammonia vapor being connected to pass through a unit which provides a recirculating volume of high-purity water, containing a high concentration of ammonium hydroxide, in contact with said flow of ammonia vapor; and a generator, connected to receive said flow of ammonia vapor from said unit and to combine said ammonia vapor with an aqueous liquid to produce an ultra-pure aqueous solution comprising ammonia; whereby said ultra-pure aqueous solution can be used within the semiconductor device fabrication facility without bulk transfer or exposure of liquid surface to any uncontrolled atmosphere.
Claim 13
Dependent Claim
18 words
The system of claim 9, further comprising a particulate filter interposed between said evaporation source and said unit.
Claim 14
Dependent Claim
14 words
The system of claim 9, wherein said liquid ammonia source consists of anhydrous ammonia.
Claim 15
Dependent Claim
17 words
The system of claim 9, wherein said recirculating volume of high-purity water does not contain any additives.
Claim 16
Dependent Claim
15 words
The system of claim 9, wherein said liquid ammonia source is of standard commercial-grade purity.
Claim 17
Dependent Claim
13 words
The system of claim 9, wherein said evaporator is a bulk storage tank.
Claim 18
Dependent Claim
25 words
The system of claim 9, wherein said evaporator operates at a controlled temperature, and is connected to receive liquid ammonia from a bulk storage tank.
Claim 19
Dependent Claim
120 words
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity ammonia for use in semiconductor manufacturing operations at said facility, comprising: an evaporation source connected to receive a liquid ammonia and to provide a flow of ammonia vapor therefrom; said flow of ammonia vapor being connected to pass through a unit which provides a recirculating volume of high-purity water, containing a high concentration of ammonium hydroxide, in contact with said flow of ammonia vapor; and a dryer, connected to receive said flow of ammonia vapor from said unit and to dry said vapor; and a piping connection which routes said aqueous solution from said dryer to at least one point of use in the semiconductor device fabrication facility.
Claim 20
Dependent Claim
120 words
An on-site subsystem, in a semiconductor device fabrication facility, for providing ultra-high-purity ammonia for use in semiconductor manufacturing operations at said facility, comprising: an evaporation source connected to receive a liquid ammonia and to provide a flow of ammonia vapor therefrom; said flow of ammonia vapor being connected to pass through a unit which provides a recirculating volume of high-purity water, containing a high concentration of ammonium hydroxide, in contact with said flow of ammonia vapor; and a dryer, connected to receive said flow of ammonia vapor from said unit and to dry said vapor; and a piping connection which routes said aqueous solution from said dryer to at least one point of use in the semiconductor device fabrication facility.
Claim 21
Dependent Claim
18 words
The system of claim 16, further comprising a particulate filter interposed between said evaporation source and said unit.
Claim 22
Dependent Claim
14 words
The system of claim 16, wherein said liquid ammonia source consists of anhydrous ammonia.
Claim 23
Dependent Claim
17 words
The system of claim 16, wherein said recirculating volume of high-purity water does not contain any additives.
Claim 24
Dependent Claim
15 words
The system of claim 16, wherein said liquid ammonia source is of standard commercial-grade purity.
Claim 25
Dependent Claim
13 words
The system of claim 16, wherein said evaporator is a bulk storage tank.
Claim 26
Dependent Claim
25 words
The system of claim 16, wherein said evaporator operates at a controlled temperature, and is connected to receive liquid ammonia from a bulk storage tank.
Claim 27
Independent Claim
95 words
A system for the preparation of ultra-high purity ammonia, said system comprising: (a) a reservoir of liquid ammonia with a vapor space above said liquid; (b) a connection for drawing vapor containing ammonia gas from said vapor space; (c) a filtration membrane removing particles from vapor thus drawn; and (d) a gas-liquid interface chamber in which filtered vapor having passed through said filtration membrane is contacted with an aqueous solution of ammonia in deionized water, the vapor thus scrubbed being purified ammonia gas; and (e) piping for removing said purified ammonia gas from said scrubber.
Claim 28
Independent Claim
95 words
A system for the preparation of ultra-high purity ammonia, said system comprising: (a) a reservoir of liquid ammonia with a vapor space above said liquid; (b) a connection for drawing vapor containing ammonia gas from said vapor space; (c) a filtration membrane removing particles from vapor thus drawn; and (d) a gas-liquid interface chamber in which filtered vapor having passed through said filtration membrane is contacted with an aqueous solution of ammonia in deionized water, the vapor thus scrubbed being purified ammonia gas; and (e) piping for removing said purified ammonia gas from said scrubber.
Claim 29
Independent Claim
153 words
A system for the manufacture of high-precision electronic components, said system comprising: (a) a production line containing a plurality of workstations arranged to perform various respective steps, on wafers containing semiconductor material, in manufacture of an electronic component, at least one of said workstations using gaseous ammonia as a source gas for operation on to said workpiece; and (b) a purification subunit connected to said at least one of said workstations by piping to supply said gaseous ammonia in ultra-high purity form, said subunit comprising: (i) a reservoir of liquid ammonia with a vapor space above said liquid ammonia; (ii) a connection for drawing vapor containing ammonia gas from said vapor space; (iii) a filtration membrane removing particles from vapor thus drawn (iv) a scrubber arranged to contact filtered vapor having passed through said filtration membrane with an aqueous solution of ammonia in deionized water, the vapor thus scrubbed being purified ammonia gas.
Claim 30
Independent Claim
153 words
A system for the manufacture of high-precision electronic components, said system comprising: (a) a production line containing a plurality of workstations arranged to perform various respective steps, on wafers containing semiconductor material, in manufacture of an electronic component, at least one of said workstations using gaseous ammonia as a source gas for operation on to said workpiece; and (b) a purification subunit connected to said at least one of said workstations by piping to supply said gaseous ammonia in ultra-high purity form, said subunit comprising: (i) a reservoir of liquid ammonia with a vapor space above said liquid ammonia; (ii) a connection for drawing vapor containing ammonia gas from said vapor space; (iii) a filtration membrane removing particles from vapor thus drawn (iv) a scrubber arranged to contact filtered vapor having passed through said filtration membrane with an aqueous solution of ammonia in deionized water, the vapor thus scrubbed being purified ammonia gas.
Claim 31
Dependent Claim
29 words
A system in accordance with claim 24 in which said subunit further comprises means for combining said purified ammonia gas with purified water to form an aqueous ammonia solution.
Claim 32
Dependent Claim
41 words
A system in accordance with claim 24 in which the distance between the point at which said purified ammonia gas leaves said purification subunit and a point of use in said at least one workstation is less than about 30 cm.
Claim 33
Dependent Claim
31 words
A system in accordance with claim 24 in which said subunit is sized to produce said purified ammonia gas at a rate of from about 2 l/h to about 200 l/h.
Claim 34
Dependent Claim
24 words
A system in accordance with claim 24 in which components (ii), (iii), and (iv) of said subunit are arranged for continuous or semi-continuous flow.
Claim 35
Independent Claim
100 words
A method for supplying a high-purity ammonia reagent to a workstation in a production line for the manufacture of a high-precision electronic component, said method comprising: (a) drawing ammonia gas from a vapor space above liquid ammonia in an ammonia-containing reservoir; (b) passing said ammonia gas through a filtration membrane removing particles greater than 0.005 micron therefrom; (c) passing said ammonia gas thus filtered through a scrubber whereby said ammonia gas is contacted with an aqueous solution of ammonia in deionized water; and (d) recovering said ammonia gas emerging from said scrubber and directing said ammonia gas to said workstation.
Claim 36
Independent Claim
100 words
A method for supplying a high-purity ammonia reagent to a workstation in a production line for the manufacture of a high-precision electronic component, said method comprising: (a) drawing ammonia gas from a vapor space above liquid ammonia in an ammonia-containing reservoir; (b) passing said ammonia gas through a filtration membrane removing particles greater than 0.005 micron therefrom; (c) passing said ammonia gas thus filtered through a scrubber whereby said ammonia gas is contacted with an aqueous solution of ammonia in deionized water; and (d) recovering said ammonia gas emerging from said scrubber and directing said ammonia gas to said workstation.
Claim 37
Dependent Claim
29 words
A method in accordance with claim 29 further comprising dissolving said ammonia gas emerging from said scrubber in purified water prior to directing said ammonia gas to said workstation.
Claim 38
Dependent Claim
29 words
A method in accordance with claim 29 further comprising passing said ammonia gas through a distillation column for further purification prior to directing said ammonia gas to said workstation.
Claim 39
Dependent Claim
50 words
A method in accordance with claim 29 further comprising the additional step of: (b') passing said ammonia gas from said scrubber through a distillation column for further purification, and dissolving said ammonia gas emerging from said distillation column in purified water prior to directing said ammonia gas to said workstation.
Claim 40
Dependent Claim
26 words
A method in accordance with claim 32 in which steps (b) and (b') are conducted at a temperature ranging from about 15° to about 35° C.
Claim 41
Dependent Claim
42 words
A method in accordance with claim 32 in which steps (b) and (b') are conducted at a temperature ranging from about 15° to about 35° C. and at a pressure of from about atmospheric pressure to about 30 psi above atmospheric pressure.
Claim 42
Dependent Claim
24 words
A method in accordance with claim 29 in which step (b) is conducted at a temperature ranging from about 100° to about 50° C.
Claim 43
Dependent Claim
24 words
A method in accordance with claim 29 in which step (b) is conducted at a temperature ranging from about 15° to about 35° C.
Claim 44
Dependent Claim
40 words
A method in accordance with claim 29 in which step (b) is conducted at a temperature ranging from about 15° to about 35° C. and at a pressure of from about atmospheric pressure to about 30 psi above atmospheric pressure.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-05-25 | 2001-11-24 | 2002-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-25 | 2005-11-24 | 2006-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-25 | 2009-11-24 | 2010-05-26 | $7700.00 | Window Closed / Lapsed |