US5310260A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Non-contact optical techniques for measuring surface conditions
Assignee: Luxtron Corp
•
Filing: 1992-12-28
•
Granted: 1994-05-10
•
Expires: 2012-12-28
Abstract
Abstract Thermal, optical, physical and chemical characteristics of a substrate (11) surface are determined with non-contact optical techniques that include illuminating (23) the surface with radiation having a ripple intensity characteristic (51), and then measuring the combined intensities (53) of that radiation after modification by the substrate surface and radiation emitted from the surface. Precise determinations of emissivity, reflectivity, temperature, changing surface composition, the existence of any layer formed on the surface and its thickness are all possible from this measurement. They may be made in situ and substantially in real time, thus allowing the measurement to control (39, 41) various processes of treating a substrate surface. This has significant applicability to semiconductor wafer processing and metal processing.
Inventors
- 👤 Charles W. Schietinger
- 👤 Bruce E. Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:34
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/02; G01B11/06; G01B11/0616; G01B11/0658; G01J; G01J5/00; G01J5/0003; G01J5/0007; G01J5/02; G01J5/026; G01J5/06; G01J5/064; G01J5/07; G01J5/08; G01J5/0801; G01J5/0815; G01J5/0818; G01J5/0821; G01J5/0846; G01J5/0878; G01J5/60; G01J5/602; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/4738; G01N21/474; G01N21/84; G01N21/8422; G01N2021/4742
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
180 words
A system adapted to measure a characteristic of a surface of an article, comprising: a source of electromagnetic radiation that contains a time varying ripple component, means for directing said source electromagnetic radiation against said article surface, first and second photodetectors each characterized by generating an electrical signal proportional to a level of electromagnetic radiation incident upon it, means positioned with respect to the article for carrying to the first photodetector both a portion of source electromagnetic radiation reflected from said article surface and electromagnetic radiation emitted by said article surface within a bandwidth of the source electromagnetic radiation, means positioned with respect to the source for carrying to the second photodetector a portion of source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, said source radiation carrying means including an elongated light pipe having a solid end thereof with either a convex shape or roughened surface that is oriented to gather source radiation therethrough, and means receiving and combining the electrical signals from the first and second photodetectors for determining characteristic of the surface.
Claim 2
Independent Claim
180 words
A system adapted to measure a characteristic of a surface of an article, comprising: a source of electromagnetic radiation that contains a time varying ripple component, means for directing said source electromagnetic radiation against said article surface, first and second photodetectors each characterized by generating an electrical signal proportional to a level of electromagnetic radiation incident upon it, means positioned with respect to the article for carrying to the first photodetector both a portion of source electromagnetic radiation reflected from said article surface and electromagnetic radiation emitted by said article surface within a bandwidth of the source electromagnetic radiation, means positioned with respect to the source for carrying to the second photodetector a portion of source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, said source radiation carrying means including an elongated light pipe having a solid end thereof with either a convex shape or roughened surface that is oriented to gather source radiation therethrough, and means receiving and combining the electrical signals from the first and second photodetectors for determining characteristic of the surface.
Claim 3
Dependent Claim
25 words
The system according to claim 1 wherein said light pipe consists essentially of material from one of a group of sapphire, cubic zirconia and quartz.
Claim 4
Dependent Claim
22 words
The system according to claim 1 wherein said solid end of said elongated light pipe has an approximately spherically shaped convex surface.
Claim 5
Dependent Claim
19 words
The system according to claim 1 wherein said solid end of said elongated light pipe has a ball shape.
Claim 6
Dependent Claim
25 words
The system according to claim 1 wherein said solid end of said elongated light pipe has a flat end roughened to form a diffuser thereacross.
Claim 7
Dependent Claim
32 words
The system according to claim 1 wherein said solid end of said elongated light pipe has both a convex shape and a roughened surface that is oriented to gather source radiation therethrough.
Claim 8
Dependent Claim
14 words
The system according to claim 6 wherein said convex shape is a conical shape.
Claim 9
Dependent Claim
41 words
The system according to claim 1 wherein said source radiation carrying means includes a plurality of elongated light pipes, each having a solid end thereof with either a convex shape or roughened surface that is oriented to gather source radiation therethrough.
Claim 10
Dependent Claim
18 words
The system according to claim 8 wherein said plurality of elongated light pipes are arranged in an array.
Claim 11
Dependent Claim
31 words
The system according to claim 1 wherein said article radiation carrying means includes a filter for filtering out radiation having a frequency greater than an absorption band edge of the article.
Claim 12
Dependent Claim
46 words
The system according to claim 1 wherein said article radiation carrying means includes a high bandwidth amplifier circuit emphasizing a frequency associated with said time varying ripple component, and a low bandwidth amplifier circuit emphasizing an average or mean value of said article radiation being carried.
Claim 13
Dependent Claim
91 words
The system according to claim 11 further comprising a third photodetector characterized by generating an electrical signal proportional to the level of electromagnetic radiation incident upon it, wherein said article radiation carrying means also carries to said third photodetector said portion of said source electromagnetic radiation referred from said article surface and electromagnetic radiation emitted by said article surface with the bandwidth of the source electromagnetic radiation, and said high bandwidth amplifier circuit is coupled to said second photodetector and said low bandwidth amplifier circuit is coupled to said third photodetector.
Claim 14
Dependent Claim
48 words
The system according to claim 12 wherein said source radiation carrying means includes a second high bandwidth amplifier circuit emphasizing a frequency associated with said time varying ripple component, and a second low bandwidth amplifier circuit emphasizing an average or mean value of said source radiation being carried.
Claim 15
Dependent Claim
83 words
The system according to claim 13 further comprising a fourth photodetector characterized by generating an electrical signal proportional to the level of electromagnetic radiation incident upon it, wherein said source radiation carrying means also carries to said fourth photodetector said portion of said source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, and said second high bandwidth amplifier circuit is coupled to said first photodetector and said second low bandwidth amplifier circuit is coupled to said fourth photodetector.
Claim 16
Dependent Claim
46 words
The system according to claim 1 wherein said source radiation carrying means includes a high bandwidth amplifier circuit emphasizing a frequency associated with said time varying ripple component, and a low bandwidth amplifier circuit emphasizing an average or mean value of said source radiation being carried.
Claim 17
Dependent Claim
81 words
The system according to claim 15 further comprising a fourth photodetector characterized by generating an electrical signal proportional to the level of electromagnetic radiation incident upon it, wherein said source radiation carrying means also carries to said fourth photodetector said portion of said source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, and said high bandwidth amplifier circuit is coupled to said first photodetector and said low bandwidth amplifier circuit is coupled to said fourth photodetector.
Claim 18
Dependent Claim
45 words
The system according to claim 1 wherein said article radiation carrying means includes a second elongated light pipe having a solid end thereof with either a convex shape or roughened surface that is oriented to gather therethrough radiation reflected and emitted from said article surface.
Claim 19
Dependent Claim
23 words
The system according to claim 17 wherein said solid end of said second elongated light pipe has an approximately spherically shaped convex surface.
Claim 20
Dependent Claim
20 words
The system according to claim 17 wherein said solid end of said second elongated light pipe has a ball shape.
Claim 21
Dependent Claim
26 words
The system according to claim 17 wherein said solid end of said second elongated light pipe has a flat end roughened to form a diffuser thereacross.
Claim 22
Dependent Claim
39 words
The system according to claim 17 wherein said solid end of said second elongated light pipe has both a convex shape and a roughened surface that is oriented to gather therethrough radiation reflected and emitted from said article surface.
Claim 23
Dependent Claim
20 words
The system according to claim 21 wherein said convex shape of said second elongated light pipe is a conical shape.
Claim 24
Dependent Claim
46 words
The system according to claim 17 wherein said article radiation carrying means includes a second plurality of elongated light pipes, each having a solid end thereof with either a convex or roughened surface that is oriented to gather radiation reflected and emitted from said article surface.
Claim 25
Dependent Claim
19 words
The system according to claim 23 wherein said second plurality of elongated light pipes are arranged in an array.
Claim 26
Independent Claim
184 words
A system adapted to measure a characteristic of a surface of an article, comprising: a source of electromagnetic radiation that contains a time varying ripple component, means for directing said source electromagnetic radiation against said article surface, first and second photodetectors each characterized by generating an electrical signal proportional to a level of electromagnetic radiation incident upon it, means positioned with respect to the article for carrying to the first photodetector both a portion of source electromagnetic radiation reflected from said article surface and electromagnetic radiation emitted by said article surface within a bandwidth of the source electromagnetic radiation, means positioned with respect to the source for carrying to the second photodetector a portion of source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, said source radiation carrying means including an elongated light pipe and at least one lens having at least one convex surface directing radiation towards said elongated light pipe oriented to gather source radiation therethrough, and means receiving and combining the electrical signals from the first and second photodetectors for determining the characteristic of the surface.
Claim 27
Independent Claim
184 words
A system adapted to measure a characteristic of a surface of an article, comprising: a source of electromagnetic radiation that contains a time varying ripple component, means for directing said source electromagnetic radiation against said article surface, first and second photodetectors each characterized by generating an electrical signal proportional to a level of electromagnetic radiation incident upon it, means positioned with respect to the article for carrying to the first photodetector both a portion of source electromagnetic radiation reflected from said article surface and electromagnetic radiation emitted by said article surface within a bandwidth of the source electromagnetic radiation, means positioned with respect to the source for carrying to the second photodetector a portion of source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, said source radiation carrying means including an elongated light pipe and at least one lens having at least one convex surface directing radiation towards said elongated light pipe oriented to gather source radiation therethrough, and means receiving and combining the electrical signals from the first and second photodetectors for determining the characteristic of the surface.
Claim 28
Dependent Claim
51 words
The system according to claim 25 wherein said article radiation carrying means includes a second elongated light pipe and a second at least one lens having at least one convex surface directing radiation towards said second elongated light pipe oriented to gather therethrough radiation reflected and emitted from said article surface.
Claim 29
Dependent Claim
31 words
The system according to claim 26 wherein said article radiation carrying means includes a filter for filtering out radiation having a frequency greater than an absorption band edge of the article.
Claim 30
Dependent Claim
46 words
The system according to claim 26 wherein said article radiation carrying means includes a high bandwidth amplifier circuit emphasizing a frequency associated with said time varying ripple component, and a low bandwidth amplifier circuit emphasizing an average or mean value of said article radiation being carried.
Claim 31
Dependent Claim
91 words
The system according to claim 26 further comprising a third photodetector characterized by generating an electrical signal proportional to the level of electromagnetic radiation incident upon it, wherein said article radiation carrying means also carries to said third photodetector said portion of said source electromagnetic radiation reflected from said article surface and electromagnetic radiation emitted by said article surface with the bandwidth of the source electromagnetic radiation, and said high bandwidth amplifier circuit is coupled to said second photodetector and said low bandwidth amplifier circuit is coupled to said third photodetector.
Claim 32
Dependent Claim
48 words
The system according to claim 29 wherein said source radiation carrying means includes a second high bandwidth amplifier circuit emphasizing a frequency associated with said time varying ripple component, and a second low bandwidth amplifier circuit emphasizing an average or mean value of said source radiation being carried.
Claim 33
Dependent Claim
83 words
The system according to claim 30 further comprising a fourth photodetector characterized by generating an electrical signal proportional to the level of electromagnetic radiation incident upon it, wherein said source radiation carrying means also carries to said fourth photodetector said portion of said source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, and said second high bandwidth amplifier circuit is coupled to said first photodetector and said second low bandwidth amplifier circuit is coupled to said fourth photodetector.
Claim 34
Dependent Claim
46 words
The system according to claim 25 wherein said source radiation carrying means includes a high bandwidth amplifier circuit emphasizing a frequency associated with said time varying ripple component, and a low bandwidth amplifier circuit emphasizing an average or mean value of said source radiation being carried.
Claim 35
Dependent Claim
81 words
The system according to claim 32 further comprising a fourth photodetector characterized by generating an electrical signal proportional to the level of electromagnetic radiation incident upon it, wherein said source radiation carrying means also carries to said fourth photodetector said portion of said source electromagnetic radiation substantially without any radiation reflected or emitted from said article surface, and said high bandwidth amplifier circuit is coupled to said first photodetector and said low bandwidth amplifier circuit is coupled to said fourth photodetector.
References Cited (Backward Citations)
US2709367A
Cited
US3288625A
Cited
US3586851A
Cited
US3686940A
Cited
US3698813A
Cited
US3971939A
Cited
US4101759A
Cited
US4222663A
Cited
US4236075A
Cited
US4437772A
Cited
US4254455A
Cited
JPS5730916A
Cited
US4417822A
Cited
US4408827A
Cited
US5004913A
Cited
US4579461A
Cited
US4576486A
Cited
US4540293A
Cited
US4632908A
Cited
US4579463A
Cited
US4750139A
Cited
US4752127A
Cited
EP0208067A1
Cited
US4752141A
Cited
US4745291A
Cited
US4799787A
Cited
US4850661A
Cited
US4983001A
Cited
US4919542A
Cited
US5048960A
Cited
US4979134A
Cited
US4896928A
Cited
JPH02118069A
Cited
US4865406A
Cited
EP0380412A2
Cited
US4989970A
Cited
US5156461A
Cited
US5180226A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-05-09 | 1997-11-08 | 1998-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-05-09 | 2001-11-08 | 2002-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-05-09 | 2005-11-08 | 2006-05-10 | $7700.00 | Window Closed / Lapsed |