Patent US5061070A successfully refreshed from Google Patents.
US5061070A
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US
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Particulate inspection of fluids using interferometric light measurements
Assignee: International Business Machines Corp
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Filing: 1988-04-22
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Granted: 1991-10-29
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Expires: 2008-04-22
Abstract
Abstract A method and apparatus for monitoring process fluids used in the manufacture of semiconductor components and other microelectronic devices relies upon detection of the phase shift of a pair of optical energy beams encountering a bubble or particle in the fluid. The system distinguishes between bubbles and particles having indices of refraction greater than the surrounding fluid and between different types and sizes of particles.
Inventors
- 👤 John S. Batchelder
- 👤 Donald M. DeCain
- 👤 Marc A. Taubenblatt
- 👤 Hermantha K. Wickramasinghe
- 👤 Clayton C. Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:40
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/41; G01N21/45; G01J; G01J9/00; G01J9/02; G01J2009/0261; G01N15/00; G01N2015/0007; G01N2015/0011; G01N2015/0042; G01N2015/0053; G01N15/02; G01N15/0205; G01N2015/0238; G01N21/84; G01N21/88; G01N21/94
Claims Analysis
Total Claims: 48
Claim 1
Independent Claim
140 words
An apparatus for detecting objects within a fluid comprising: means for transmitting a beam of optical energy; first optical means for splitting said beam of optical energy into two substantially parallel beams of different polarization, having axes which are laterally displaced and focused in a focal plane located where a fluid is to be inspected, which focal plane is substantially normal to the beam axes; second optical means for recombining said two beams into a single beam after said beams travel through the focal plane a distance greater than the depth of focus of said two beams; third optical means for separating said single beam into two beams, and detection means for receiving said two beams from said third optical means and providing a signal responsive to a phase shift between said two beams after traveling through the focal plane.
Claim 2
Independent Claim
140 words
An apparatus for detecting objects within a fluid comprising: means for transmitting a beam of optical energy; first optical means for splitting said beam of optical energy into two substantially parallel beams of different polarization, having axes which are laterally displaced and focused in a focal plane located where a fluid is to be inspected, which focal plane is substantially normal to the beam axes; second optical means for recombining said two beams into a single beam after said beams travel through the focal plane a distance greater than the depth of focus of said two beams; third optical means for separating said single beam into two beams, and detection means for receiving said two beams from said third optical means and providing a signal responsive to a phase shift between said two beams after traveling through the focal plane.
Claim 3
Dependent Claim
21 words
An apparatus as set forth in claim 1, wherein said first optical means and said second optical means includes Nomarski lenses.
Claim 4
Dependent Claim
17 words
An apparatus as set forth in claim 1, wherein said third optical means includes a Wollaston prism.
Claim 5
Dependent Claim
29 words
Apparatus as set forth in claim 1, wherein said first optical means and said second optical means include Nomarski lenses and said third optical means includes a Wollaston prism.
Claim 6
Dependent Claim
25 words
An apparatus as set forth in claim 1, wherein said third optical means spatially separates said single beam into beams separated by substantially 90 degrees.
Claim 7
Dependent Claim
14 words
An apparatus as set forth in claim 1, wherein said detection means is non-linear.
Claim 8
Dependent Claim
18 words
An apparatus as set forth in claim 1, wherein said detection means includes photodetectors and an isolation amplifier.
Claim 9
Dependent Claim
26 words
An apparatus as set forth in claim 1, wherein said two beams of different polarization are each polarized in a plane substantially normal to each other.
Claim 10
Dependent Claim
35 words
An apparatus as set forth in claim 1, further comprising analysis means for receiving said signal from said detection means and providing an output signal indicative of a characteristic of an object in the fluid.
Claim 11
Dependent Claim
32 words
An apparatus as set forth in claim 9, wherein said analysis means includes a counter for providing a signal indicative of a quantity of objects being detected during a predetermined time interval.
Claim 12
Dependent Claim
16 words
An apparatus as set forth in claim 9, wherein said characteristic is a type of object.
Claim 13
Dependent Claim
15 words
An apparatus as set forth in claim 9, wherein said characteristic is size of object.
Claim 14
Dependent Claim
18 words
An apparatus as set forth in claim 1, wherein said beam of optical energy is a laser beam.
Claim 15
Dependent Claim
24 words
An apparatus as set forth in claim 1, further including a flow cell disposed between said first optical means and said second optical means.
Claim 16
Independent Claim
121 words
A method of detecting objects in a fluid comprising the steps of: transmitting a beam of optical energy; splitting said beam of optical energy into two substantially parallel beams of different polarization having axes which are laterally displaced and focussed in a focal plane located in a fluid to be inspected, which focal plane is substantially normal to the beam axes; recombining said two beams into a single beam after said beams travel through the focal plane a distance greater than the depth of focus of said two beams; separating said single beam into two beams, and detecting said separated two beams for providing a signal responsive to a phase shift of said two beams after traveling through said focal plane.
Claim 17
Independent Claim
121 words
A method of detecting objects in a fluid comprising the steps of: transmitting a beam of optical energy; splitting said beam of optical energy into two substantially parallel beams of different polarization having axes which are laterally displaced and focussed in a focal plane located in a fluid to be inspected, which focal plane is substantially normal to the beam axes; recombining said two beams into a single beam after said beams travel through the focal plane a distance greater than the depth of focus of said two beams; separating said single beam into two beams, and detecting said separated two beams for providing a signal responsive to a phase shift of said two beams after traveling through said focal plane.
Claim 18
Dependent Claim
29 words
A method as set forth in claim 15, wherein each beam of said two beams of different polarization being polarized in a plane substantially normal to the other beam.
Claim 19
Dependent Claim
27 words
A method as set forth in claim 15, wherein said separating said single beam separates said single beam into two beams, spatially separated by substantially 90 degrees.
Claim 20
Dependent Claim
30 words
A method as set forth in claim 15, further including analyzing said signal responsive to a phase shift for providing a signal indicative of a characteristic of a detected object.
Claim 21
Dependent Claim
34 words
A method as set forth in claim 15, further including analyzing said signal responsive to a phase shift for providing a signal indicative of a quantity of objects detected during a predetermined time interval.
Claim 22
Dependent Claim
15 words
A method as set forth in claim 15, wherein said optical energy is laser energy.
Claim 23
Independent Claim
135 words
An apparatus for detecting and analyzing object in a system for manufacturing semiconductor or other microelectronic devices comprising: a flow cell adapted to pass therethrough an object containing fluid; means for transmitting a beam of optical energy; first optical means for splitting said beam of optical energy into two substantially parallel beams of different polarization, having axes which are laterally displaced and focussed in a focal plane located in said flow cell, which focal plane is substantially normal to the beam axes; second optical means for recombining said two beams into a single beam after said beams travel through said flow cell; third optical means for spatially separating said single beam into two beams, and detection means for providing a signal responsive to a phase shift of said two beams from said third optical means.
Claim 24
Independent Claim
135 words
An apparatus for detecting and analyzing object in a system for manufacturing semiconductor or other microelectronic devices comprising: a flow cell adapted to pass therethrough an object containing fluid; means for transmitting a beam of optical energy; first optical means for splitting said beam of optical energy into two substantially parallel beams of different polarization, having axes which are laterally displaced and focussed in a focal plane located in said flow cell, which focal plane is substantially normal to the beam axes; second optical means for recombining said two beams into a single beam after said beams travel through said flow cell; third optical means for spatially separating said single beam into two beams, and detection means for providing a signal responsive to a phase shift of said two beams from said third optical means.
Claim 25
Dependent Claim
21 words
An apparatus as set forth in claim 21, wherein said first optical means and said second optical means includes Nomarski lenses.
Claim 26
Dependent Claim
17 words
An apparatus as set forth in claim 21, wherein said third optical means includes a Wollaston prism.
Claim 27
Dependent Claim
30 words
An apparatus as set forth in claim 21, wherein said first optical means and said second optical means includes Nomarski lenses and said third optical means includes a Wollaston prism.
Claim 28
Dependent Claim
19 words
An apparatus as set forth in claim 21, wherein said spatially separated beams are separated by substantially 90 degrees.
Claim 29
Dependent Claim
14 words
An apparatus as set forth in claim 21, wherein said detection means is non-linear.
Claim 30
Dependent Claim
18 words
An apparatus as set forth in claim 21, wherein said detection means includes photodetectors and an isolation amplifier.
Claim 31
Dependent Claim
26 words
An apparatus as set forth in claim 21, wherein said two beams of different polarization are each polarized in a plane substantially normal to each other.
Claim 32
Dependent Claim
38 words
An apparatus as set forth in claim 21, further comprising analysis means for receiving said signals responsive to a phase shift and providing an output signal indicative of a characteristic of a detected object in the flow cell.
Claim 33
Dependent Claim
33 words
An apparatus as set forth in claim 29, wherein said analysis means includes a counter for providing an output signal indicative of a quantity of objects being detected during a predetermined time interval.
Claim 34
Dependent Claim
16 words
An apparatus as set forth in claim 29, wherein said characteristic is a type of object.
Claim 35
Dependent Claim
15 words
An apparatus as set forth in claim 29, wherein said characteristic is size of object.
Claim 36
Dependent Claim
15 words
An apparatus as set forth in claim 21, wherein said optical energy is laser energy.
Claim 37
Dependent Claim
124 words
In a system for manufacturing semiconductor or other microelectronic devices, a method for monitoring process fluids comprising the steps of: passing a process fluid through a flow cell; transmitting a beam of optical energy; splitting said beam of optical energy into two substantially parallel beams of different polarization, having axes which are laterally displaced and focussed in a focal plane located in the flow cell, which focal plane is substantially normal to the beam axes; recombining said two beams into a single beam after said beams travel through the flow cell; spatially separating said single beam into two beams, and detecting said spatially separated beams for providing a signal responsive to a phase shift of said two beams after traveling through the flow cell.
Claim 38
Dependent Claim
124 words
In a system for manufacturing semiconductor or other microelectronic devices, a method for monitoring process fluids comprising the steps of: passing a process fluid through a flow cell; transmitting a beam of optical energy; splitting said beam of optical energy into two substantially parallel beams of different polarization, having axes which are laterally displaced and focussed in a focal plane located in the flow cell, which focal plane is substantially normal to the beam axes; recombining said two beams into a single beam after said beams travel through the flow cell; spatially separating said single beam into two beams, and detecting said spatially separated beams for providing a signal responsive to a phase shift of said two beams after traveling through the flow cell.
Claim 39
Dependent Claim
29 words
A method as set forth in claim 34, wherein each beam of said two beams of different polarization being polarized in a plane substantially normal to the other beam.
Claim 40
Dependent Claim
28 words
A method as set forth in claim 34, wherein said spatially separating said single beam separates said single beam into two beams spatially separated by substantially 90 degrees.
Claim 41
Dependent Claim
31 words
A method as set forth in claim 34, further including analyzing said signal responsive to a phase shift for providing an output signal indicative of a characteristic of a detected object.
Claim 42
Dependent Claim
35 words
A method as set forth in claim 34, further including analyzing said signal responsive to a phase shift for providing an output signal indicative of a quantity of objects detected during a predetermined time interval.
Claim 43
Dependent Claim
20 words
A method as set forth in claim 34, wherein said beam of optical energy is a beam of laser energy.
Claim 44
Dependent Claim
14 words
A method as set forth in claim 34, wherein said detecting includes non-linear detection.
Claim 45
Independent Claim
108 words
An apparatus for inspecting a fluid comprising: means including Nomarski objectives for transmitting into a fluid to be inspected two substantially parallel beams of optical energy, said beams being mutually coherent, of different polarizations, having axes which are laterally displaced and being focussed in a focal plane located where the fluid is to be inspected which focal plane is substantially normal to the beam axes; detector means; means for coherently interfering at said detector means said beams after passing through the focal plane a distance greater than the depth of focus of said beams, and means for generating a signal commensurate with difference of phase between said beams.
Claim 46
Independent Claim
108 words
An apparatus for inspecting a fluid comprising: means including Nomarski objectives for transmitting into a fluid to be inspected two substantially parallel beams of optical energy, said beams being mutually coherent, of different polarizations, having axes which are laterally displaced and being focussed in a focal plane located where the fluid is to be inspected which focal plane is substantially normal to the beam axes; detector means; means for coherently interfering at said detector means said beams after passing through the focal plane a distance greater than the depth of focus of said beams, and means for generating a signal commensurate with difference of phase between said beams.
Claim 47
Independent Claim
108 words
An apparatus for inspecting a fluid comprising: means for transmitting into a fluid to be inspected two substantially parallel beams of optical energy, said beams being mutually coherent, of different polarizations, having axes which are laterally displaced and being focussed in a focal plane located where the fluid is to be inspected which focal plane is substantially normal to the beam axes; detector means; means including Norarski objectives for coherently interfering at said detector means said beams after passing through the focal plane a distance greater than the depth of focus of said beams, and means for generating a signal commensurate with difference of phase between said beams.
Claim 48
Independent Claim
108 words
An apparatus for inspecting a fluid comprising: means for transmitting into a fluid to be inspected two substantially parallel beams of optical energy, said beams being mutually coherent, of different polarizations, having axes which are laterally displaced and being focussed in a focal plane located where the fluid is to be inspected which focal plane is substantially normal to the beam axes; detector means; means including Norarski objectives for coherently interfering at said detector means said beams after passing through the focal plane a distance greater than the depth of focus of said beams, and means for generating a signal commensurate with difference of phase between said beams.
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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) | 1994-10-28 | 1995-04-29 | 1995-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-10-28 | 1999-04-29 | 1999-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-10-28 | 2003-04-29 | 2003-10-29 | $7700.00 | Window Closed / Lapsed |