US5641419A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for optical temperature control
Assignee: Individual
•
Filing: 1992-11-03
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Granted: 1997-06-24
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Expires: 2012-11-03
Abstract
Abstract The radiation generated by at least one radiation source is controlled so as to generate a constant radiation intensity, thereby to cause the object to be heated, and the radiation intensity from the object at a first wavelength is sensed until it is equal to the present radiation intensity generated by the at least one radiation source, whereby the temperature of the object has a predetermined value. From that time on, the development of the actual temperature of the object is controlled accurately according to a predetermined program merely by sensing the radiation intensity from the object at a second wavelength larger than the first wavelength, and using the measuring signal representative of the sensed radiation intensity to continuously control the radiation intensity generated by the at least one radiation source.
Inventors
- 👤 Peter Vandenabeele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 23:00
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/60; G05; G05D; G05D23/00; G05D23/19; G05D23/27; G01J5/602
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
145 words
A method for optical temperature control of an object placed inside a heating chamber including at least one radiation source by means of at least one radiation detector directed to said object so as to sense the radiation intensity from the object, comprising the steps of: controlling the at least one radiation source so as to generate a source radiation intensity, thereby to cause the object to be heated, sensing the radiation intensity from the object at a first wavelength until said radiation intensity is equal to the source radiation intensity, whereby the temperature of the object has a predetermined value, sensing the radiation intensity from the object at a second wavelength larger than the first wavelength, and using the sensed radiation intensity at the second wavelength to further control the source radiation intensity, thereby to control the development of the temperature of said object.
Claim 2
Independent Claim
145 words
A method for optical temperature control of an object placed inside a heating chamber including at least one radiation source by means of at least one radiation detector directed to said object so as to sense the radiation intensity from the object, comprising the steps of: controlling the at least one radiation source so as to generate a source radiation intensity, thereby to cause the object to be heated, sensing the radiation intensity from the object at a first wavelength until said radiation intensity is equal to the source radiation intensity, whereby the temperature of the object has a predetermined value, sensing the radiation intensity from the object at a second wavelength larger than the first wavelength, and using the sensed radiation intensity at the second wavelength to further control the source radiation intensity, thereby to control the development of the temperature of said object.
Claim 3
Dependent Claim
34 words
A method as claimed in claim 1, wherein the first and second wavelength radiation intensities are sensed using one radiation detector having means to calibrate the detector at said first and said second wavelength.
Claim 4
Dependent Claim
37 words
A method as claimed in claim 1, wherein the first and second wavelength radiation intensities are sensed using two radiation detectors, one being calibrated at said first wavelength and the second being calibrated at said second wavelength.
Claim 5
Dependent Claim
54 words
A method as claimed in claim 1, further comprising the step of sensing the radiation intensity from the object at a third wavelength lower than the first wavelength and using the measuring signal representative of the sensed radiation intensity to determine the present reflectivity of the object at a particular location of said object.
Claim 6
Independent Claim
219 words
An apparatus for optical temperature control of an object comprising a chamber including at least one radiation source positioned so as to irradiate an object placed inside the chamber, a radiation detector positioned to be directed to an object placed inside the chamber so as to sense the radiation from the object at a first wavelength and produce a first measuring signal representative of the sensed radiation, and a control unit connected to receive the signal for controlling the radiation source, further comprising at least one second radiation detector positioned to sense radiation from the object, said second radiation detector being calibrated to a second wavelength different from the first wavelength thereby to sense a radiation intensity substantially different from the radiation intensity at said first wavelength at the first radiation detector, and producing a second measuring signal representative of the sensed radiation intensity at said second wavelength, means for sensing the radiation intensity of the at least one radiation source, and means for producing a source intensity signal representative of the radiation intensity of the at least one radiation source, wherein the control unit is arranged to produce a continuous control signal for the radiation source as a function of the second measuring signal in response to the first measuring signal being equal to said source intensity signal.
Claim 7
Independent Claim
219 words
An apparatus for optical temperature control of an object comprising a chamber including at least one radiation source positioned so as to irradiate an object placed inside the chamber, a radiation detector positioned to be directed to an object placed inside the chamber so as to sense the radiation from the object at a first wavelength and produce a first measuring signal representative of the sensed radiation, and a control unit connected to receive the signal for controlling the radiation source, further comprising at least one second radiation detector positioned to sense radiation from the object, said second radiation detector being calibrated to a second wavelength different from the first wavelength thereby to sense a radiation intensity substantially different from the radiation intensity at said first wavelength at the first radiation detector, and producing a second measuring signal representative of the sensed radiation intensity at said second wavelength, means for sensing the radiation intensity of the at least one radiation source, and means for producing a source intensity signal representative of the radiation intensity of the at least one radiation source, wherein the control unit is arranged to produce a continuous control signal for the radiation source as a function of the second measuring signal in response to the first measuring signal being equal to said source intensity signal.
Claim 8
Dependent Claim
38 words
An apparatus as claimed in claim 5, further comprising a window-shaped filter having a predetermined size positioned across a field of view of the second radiation detector, said filter being adapted to pass radiation at said second wavelength.
Claim 9
Dependent Claim
25 words
An apparatus as claimed in claim 6, wherein the second radiation detector has a field of view substantially corresponding to the size of the filter.
Claim 10
Dependent Claim
28 words
An apparatus as claimed in claim 7, wherein the window-shaped filter is mounted in an opening formed in a tube arranged to receive the object to be heated.
Claim 11
Dependent Claim
84 words
An apparatus as claimed in claim 5, further comprising at least one third radiation detector directed to the object to sense radiation intensity from the object at a third wavelength lower than the first wavelength and produce a third measuring signal representative of the sensed radiation intensity, the output of said third radiation detector being connected to the control unit, said control unit being arranged to determine the reflectivity of a particular area on the object as a function of said third measuring signal.
Claim 12
Independent Claim
162 words
An apparatus for optical temperature control of an object, comprising: at least one radiation source positioned to irradiate the object, said at least one radiation source having a controllable intensity; means for sensing the intensity of said at least one radiation source and generating a corresponding source signal; a first radiation detector positioned to detect radiation at a first wavelength, said first radiation detector generating a first signal representing an intensity of radiation detected at the first wavelength; a second radiation detector positioned to detect radiation at a second wavelength, said second radiation detector generating a second signal representing an intensity of radiation detected at the second wavelength; and a controller coupled to the at least one radiation source, the first radiation detector and the second radiation detector, wherein said controller compares said first signal to said source signal and generates a control signal for adjusting the controllable intensity of the at least one radiation source in accordance with the second signal.
Claim 13
Independent Claim
162 words
An apparatus for optical temperature control of an object, comprising: at least one radiation source positioned to irradiate the object, said at least one radiation source having a controllable intensity; means for sensing the intensity of said at least one radiation source and generating a corresponding source signal; a first radiation detector positioned to detect radiation at a first wavelength, said first radiation detector generating a first signal representing an intensity of radiation detected at the first wavelength; a second radiation detector positioned to detect radiation at a second wavelength, said second radiation detector generating a second signal representing an intensity of radiation detected at the second wavelength; and a controller coupled to the at least one radiation source, the first radiation detector and the second radiation detector, wherein said controller compares said first signal to said source signal and generates a control signal for adjusting the controllable intensity of the at least one radiation source in accordance with the second signal.
Claim 14
Dependent Claim
26 words
An apparatus as claimed in claim 10, wherein said first radiation detector and said second radiation detector are directed to a first location on said object.
Claim 15
Dependent Claim
58 words
An apparatus as claimed in claim 11, further comprising an additional first radiation detector and an additional second radiation detector, wherein said additional first and second radiation detectors are directed to a second location on said object that is different than said first location on the object, whereby temperature control at different locations on the object is obtained.
Claim 16
Dependent Claim
14 words
An apparatus as claimed in claim 10, wherein the object is a semiconductor wafer.
Claim 17
Dependent Claim
17 words
An apparatus as claimed in claim 10, wherein said second wavelength is larger than said first wavelength.
Claim 18
Dependent Claim
17 words
An apparatus as claimed in claim 10, further comprising a tube within which said object is mounted.
Claim 19
Dependent Claim
18 words
An apparatus as claimed in claim 15, wherein said at least one radiation source comprises a halogen lamp.
Claim 20
Dependent Claim
32 words
An apparatus as claimed in claim 16, wherein said sensing means comprises at least one of a lamp resistance measuring device, a lamp power measuring device and a tube temperature measuring device.
References Cited (Backward Citations)
GB472146A
Cited
FR1453784A
Cited
GB1222167A
Cited
JPS605508A
Cited
US4854724A
Cited
US4729668A
Cited
US4818102A
Cited
US5354323A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2000-06-23 | 2000-12-23 | 2001-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-23 | 2004-12-23 | 2005-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-06-23 | 2008-12-23 | 2009-06-24 | $7700.00 | Window Closed / Lapsed |