WO1992012405A1 - Method and device for measuring the temperature of an object and heating method - Google Patents

Method and device for measuring the temperature of an object and heating method Download PDF

Info

Publication number
WO1992012405A1
WO1992012405A1 PCT/EP1992/000039 EP9200039W WO9212405A1 WO 1992012405 A1 WO1992012405 A1 WO 1992012405A1 EP 9200039 W EP9200039 W EP 9200039W WO 9212405 A1 WO9212405 A1 WO 9212405A1
Authority
WO
WIPO (PCT)
Prior art keywords
radiation
pick
change
temperature
halogen lamps
Prior art date
Application number
PCT/EP1992/000039
Other languages
French (fr)
Inventor
Peter Michael Noel Vandenabeele
Original Assignee
Interuniversitair Micro Elektronica Centrum Vzw
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Interuniversitair Micro Elektronica Centrum Vzw filed Critical Interuniversitair Micro Elektronica Centrum Vzw
Priority to KR1019920702168A priority Critical patent/KR920704108A/en
Priority to JP92502086A priority patent/JPH05507356A/en
Publication of WO1992012405A1 publication Critical patent/WO1992012405A1/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/02—Constructional details
    • G01J5/08—Optical arrangements
    • G01J5/0801—Means for wavelength selection or discrimination
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/0003—Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiant heat transfer of samples, e.g. emittance meter
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
    • G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/0003—Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiant heat transfer of samples, e.g. emittance meter
    • G01J5/0007—Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiant heat transfer of samples, e.g. emittance meter of wafers or semiconductor substrates, e.g. using Rapid Thermal Processing
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/02—Constructional details
    • G01J5/08—Optical arrangements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/02—Constructional details
    • G01J5/08—Optical arrangements
    • G01J5/0803—Arrangements for time-dependent attenuation of radiation signals
    • G01J5/0804—Shutters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/02—Constructional details
    • G01J5/08—Optical arrangements
    • G01J5/0896—Optical arrangements using a light source, e.g. for illuminating a surface
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J5/80—Calibration
    • G01J5/802—Calibration by correcting for emissivity
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
    • G01J2005/0074—Radiation pyrometry, e.g. infrared or optical thermometry having separate detection of emissivity

Definitions

  • the present invention provides a method for measuring the temperature of an object that is heated by one or more radiation sources, wherein radiation generated by the object is received in at least one radiation pick-up and wherein the radiation sources are changed at least partially in intensity at a predetermined cyclic rate of change and wherein on the basis of the change in the radiation value measured by the radiation pick-up the degree of compensation
  • SUBSTITUTESHEET for the reflectivity and/or emissivity of the object is determined.
  • the present invention further provides a device for measuring the temperature of an object comprising: - one or more radiation sources for heating the ob ⁇ ject;
  • the present invention provides a method for heating an object wherein the compensation steps of the above method and device are applied.
  • fig. 1 shows a schematic view in section of a prefer ⁇ red embodiment of the present invention
  • fig. 2 shows a view over the line II-II in fig. 1
  • fig. 3 and 4 show graphs elucidating the preferred embodiment of the present invention
  • fig. 5 shows a further graph of measurements according to the present invention.
  • An object W for instance a wafer of Si material which may or may not be provided with insulating portions, is placed in a schematically designated RTP device 1 (fig. 1, 2) for heating by halogen lamps 2, 3 arranged respectively in an upper part 4 and a lower part 5.
  • a radiation pick-up 6 is provided with a lens 7 oriented through a schematically designated opening 8 between the halogen lamps 3 and towards the wafer .
  • a large aperture ⁇ is obtained so that, as indicated with broken lines in fig. 1, rays of
  • SUBSTITUTESHEET halogen lamps 3 reflected against wafer W as well as radiation from the halogen lamp 2 passing through the wafer W can be received in a sufficiently large solid angle.
  • a curve C] measured by a thermocouple indicates the temperature T as a function of time t, when the power is applied to the lamps 2 of fig. 1 as shown in fig. 3.
  • the curve C 2 shows the signal 6 received by the pyrometer 6, wherein the pyrometer is sensitive to radiation around a wavelength of 1.7 ⁇ m.
  • the reflectivity of the object W can be determined in the same way using variations in the intensity generated by the lamps 3.
  • the output signal of the radiation pick-up or pyrometer 6 can be compensated for transmissivity and reflectivity of the wafer W-using correlation techniques and a reliable temperature measurement of the wafer can be obtained irrespective of the material thereof, the roughness etc.
  • halogen lamps 2 and 3 respectively are varied or modulated with mutually differing frequencies
  • SUBSTITUTESHEET compensation can be made separately in the output signal of the pyrometer 6 for either reflectivity or emissivity with per se known correlation techniques.
  • the rear wall of the upper part 4 of the device 1 is preferably provided with a non-reflecting or black layer such as a filter or organic coating layer.
  • a window-shaped filter is pre ⁇ ferably placed in front of the pyrometer 6, whereby a more uniform distribution of the radiation intensity of the lamps 2 over the aperture ⁇ is obtained.
  • the curve C 3 measured according to the method of the present invention corresponds the temperature C 4 of the wafer as measured by a thermocouple.
  • C 5 and C 6 show the signal of a pyrometer and the emissivity resp.

Abstract

Method for measuring the temperature of an object that is heated by means of one or more radiation sources, wherein radiation generated by the object is received in at least one radiation pick-up and wherein the radiation sources are changed at least partially in intensity at a predetermined cyclic rate of change and wherein on the basis of the change in the radiation value measured by the radiation pick-up the degree of compensation for the reflectivity and/or emissivity of the object is determined.

Description

METHOD AND DEVICE FOR MEASURING THE TEMPERATURE OF AM OBJECT AND HEATING METHOD
Particularly in the heating of semiconductor wafers, which takes place for a short time in so-called RTP (Rapid Thermal Processing) equipment, it is difficult to accurately determine the temperature of a wafer due to ambient influen- ces and transparency of the wafer.
Earlier patent applications of applicant in this technical field are the Netherlands patent application 89.00003 and corresponding European and American applications, in addition to the as yet unpublished Netherlands patent application 90.01200.
For an exact temperature measurement it is necessary to know the correct correlation between emitted radiation and temperature. Significant problems here are the following: - the radiation emitted by an object is always smaller than the radiation emitted by a "black" object according to Boltzmann's Law. For actual objects the emissivity eint has a value between 0 and 1;
- due to reflections (and transmissions) in the en- vironment an emissivity measured in practice is always grea¬ ter than the above stated eint;
- if an object is simultaneously heated, the thermal radiation of a heat source affects the measurement;
The present invention provides a method for measuring the temperature of an object that is heated by one or more radiation sources, wherein radiation generated by the object is received in at least one radiation pick-up and wherein the radiation sources are changed at least partially in intensity at a predetermined cyclic rate of change and wherein on the basis of the change in the radiation value measured by the radiation pick-up the degree of compensation
SUBSTITUTESHEET for the reflectivity and/or emissivity of the object is determined.
The present invention further provides a device for measuring the temperature of an object comprising: - one or more radiation sources for heating the ob¬ ject;
- a radiation pick-up for receiving the radiation generated by the object;
- modulation means for changing the intensity of the radiation sources at a predetermined cyclic rate of change; and
- compensation means for determining the reflectivity and/or emissivity of the object on the basis of the radiation value measured by the radiation pick-up. Finally, the present invention provides a method for heating an object wherein the compensation steps of the above method and device are applied.
Further features, details and advantages of the pre¬ sent invention will be elucidated in the light of a descrip- tion of a preferred embodiment thereof with reference to the annexed drawing, in which: fig. 1 shows a schematic view in section of a prefer¬ red embodiment of the present invention; fig. 2 shows a view over the line II-II in fig. 1; fig. 3 and 4 show graphs elucidating the preferred embodiment of the present invention. fig. 5 shows a further graph of measurements according to the present invention.
An object W, for instance a wafer of Si material which may or may not be provided with insulating portions, is placed in a schematically designated RTP device 1 (fig. 1, 2) for heating by halogen lamps 2, 3 arranged respectively in an upper part 4 and a lower part 5. In addition a radiation pick-up 6 is provided with a lens 7 oriented through a schematically designated opening 8 between the halogen lamps 3 and towards the wafer . Using the relatively strong lens 7 a large aperture Ω is obtained so that, as indicated with broken lines in fig. 1, rays of
SUBSTITUTESHEET halogen lamps 3 reflected against wafer W as well as radiation from the halogen lamp 2 passing through the wafer W can be received in a sufficiently large solid angle.
When the halogen lamp intensity I is varied in time t as shown schematically in fig. 3, wherein the average power supplied to the lamps amounts to 9 kw, while the intensity is varied at a frequency of 4 Hz and the minimum intensity amounts to roughly 50% of the maximum, such fluctuations are also detected by the radiation pick-up or pyrometer 6. This can be seen in fig. 4 in which a curve C] measured by a thermocouple indicates the temperature T as a function of time t, when the power is applied to the lamps 2 of fig. 1 as shown in fig. 3. The curve C2 shows the signal 6 received by the pyrometer 6, wherein the pyrometer is sensitive to radiation around a wavelength of 1.7 μm. It can be seen clearly that after approximately 20 seconds the fluctuations in the signal C2 have entirely disappeared, which means that at a temperature of about 600°C of the wafer W (see curve C]) the wafer has become impermeable to the infrared radiation generated by the halogen lamp 2, this corresponding with theoretically established values therefor. It will be apparent that on the basis of the magnitude of the fluctuations in the signal of the pyrometer C2 the transmissivity of the object W can be determined at any temperature.
The reflectivity of the object W can be determined in the same way using variations in the intensity generated by the lamps 3.
When during heating of the object with halogen lamps 2 and/or 3 from the top and bottom respectively the intensity is subject to cyclic variation, the output signal of the radiation pick-up or pyrometer 6 can be compensated for transmissivity and reflectivity of the wafer W-using correlation techniques and a reliable temperature measurement of the wafer can be obtained irrespective of the material thereof, the roughness etc.
If the halogen lamps 2 and 3 respectively are varied or modulated with mutually differing frequencies,
SUBSTITUTESHEET compensation can be made separately in the output signal of the pyrometer 6 for either reflectivity or emissivity with per se known correlation techniques.
Side walls around the lamps 2 and 3 preferably take a reflecting form so that the most uniform possible radiation source is "seen" by the pyrometer. The rear wall of the upper part 4 of the device 1 is preferably provided with a non-reflecting or black layer such as a filter or organic coating layer. In order to compensate for the discrete character of the individual halogen lamps a window-shaped filter is pre¬ ferably placed in front of the pyrometer 6, whereby a more uniform distribution of the radiation intensity of the lamps 2 over the aperture Ω is obtained. In fig. 5 it is shown that the curve C3 measured according to the method of the present invention corresponds the temperature C4 of the wafer as measured by a thermocouple. Further C5 and C6 show the signal of a pyrometer and the emissivity resp.
SUBSTITUTESHEET

Claims

1. Method for measuring the temperature of an object that is heated by means of one or more radiation sources, wherein radiation generated by the object is received in at least one radiation pick-up and wherein the radiation sources are changed at least partially in intensity at a predetermined cyclic rate of change and wherein on the basis of the change in the radiation value measured by the radiation pick-up the degree of compensation for the reflectivity and/or emissivity of the object is determined.
2. Method as claimed in claim 1, wherein the cyclic rate of change amounts to 1-10 Hz and the degree of change or percentage modulation amounts to approximately 50% of the average intensity of the radiation sources.
3. Device for measuring the temperature of an object comprising:
- one or more radiation sources for heating the ob¬ ject;
- a radiation pick-up for receiving the radiation generated by the object; - modulation means for changing the intensity of the radiation sources at a predetermined cyclic rate of change; and
- compensation means for determining the reflectivity and/or emissivity of the object on the basis of the radiation value measured by the radiation pick-up.
4. Device as claimed in claim 3, wherein the radiation source comprises a series of elongate halogen lamps in mutually adjacent position.
5. Device as claimed in claim 3 or 4, wherein the halogen lamps are surrounded by flat mirrors.
6. Device as claimed in claim 3, 4 or 5, wherein a lens is disposed in front of the radiation pick-up to obtain a large aperture for the radiation pick-up.
7. Device as claimed in any of the claims 3-6, wherein the radiation pick-up is arranged behind a series of
SUBSTITUTESHEET halogen lamps and is oriented through an opening between the halogen lamps.
8. Device as claimed in claim 5, 6 or 7, wherein a window-shaped filter is arranged in front of the radiation pick-up.
9. Method for heating an object wherein the method according to claim 1 or 2 and/or the device according to any of the claims 3-8 is applied.
*****
SUBSTITUTESHEET
PCT/EP1992/000039 1991-01-08 1992-01-08 Method and device for measuring the temperature of an object and heating method WO1992012405A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
KR1019920702168A KR920704108A (en) 1991-01-08 1992-01-08 Method for measuring the temperature of an object
JP92502086A JPH05507356A (en) 1991-01-08 1992-01-08 Object temperature measurement method and device and heating method

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL9100018A NL9100018A (en) 1991-01-08 1991-01-08 METHOD AND APPARATUS FOR MEASURING THE TEMPERATURE OF AN OBJECT, AND HEATING METHOD
NL9100018 1991-01-08

Publications (1)

Publication Number Publication Date
WO1992012405A1 true WO1992012405A1 (en) 1992-07-23

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ID=19858700

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1992/000039 WO1992012405A1 (en) 1991-01-08 1992-01-08 Method and device for measuring the temperature of an object and heating method

Country Status (5)

Country Link
EP (1) EP0519033A1 (en)
JP (1) JPH05507356A (en)
KR (1) KR920704108A (en)
NL (1) NL9100018A (en)
WO (1) WO1992012405A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993010426A1 (en) * 1991-11-22 1993-05-27 Secretary Of State For Trade And Industry Temperature measuring apparatus
US5444815A (en) * 1993-12-16 1995-08-22 Texas Instruments Incorporated Multi-zone lamp interference correction system
DE4414391A1 (en) * 1994-04-26 1995-11-02 Ast Elektronik Gmbh Method and device for wave vector selective pyrometry in rapid heating systems
DE19534440A1 (en) * 1995-09-16 1997-03-20 Bergmann Hans Wilhelm Contactless measurement of temperature of coloured material

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4558411B2 (en) * 2004-08-24 2010-10-06 富士通セミコンダクター株式会社 Rapid heat treatment apparatus and method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2153077A1 (en) * 1971-10-11 1973-04-19 Bbc Brown Boveri & Cie METHOD FOR CONTACTLESS MEASUREMENT OF SURFACE TEMPERATURE ON AN OBJECT
US4799788A (en) * 1986-08-08 1989-01-24 Electricite De France Service National Process for measuring the temperature of a body by optical detection and modulated heating
US4890245A (en) * 1986-09-22 1989-12-26 Nikon Corporation Method for measuring temperature of semiconductor substrate and apparatus therefor
EP0381253A1 (en) * 1989-01-02 1990-08-08 Interuniversitair Microelektronica Centrum Vzw Apparatus and method for processing one or more wafers of material
US4956538A (en) * 1988-09-09 1990-09-11 Texas Instruments, Incorporated Method and apparatus for real-time wafer temperature measurement using infrared pyrometry in advanced lamp-heated rapid thermal processors

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2153077A1 (en) * 1971-10-11 1973-04-19 Bbc Brown Boveri & Cie METHOD FOR CONTACTLESS MEASUREMENT OF SURFACE TEMPERATURE ON AN OBJECT
US4799788A (en) * 1986-08-08 1989-01-24 Electricite De France Service National Process for measuring the temperature of a body by optical detection and modulated heating
US4890245A (en) * 1986-09-22 1989-12-26 Nikon Corporation Method for measuring temperature of semiconductor substrate and apparatus therefor
US4956538A (en) * 1988-09-09 1990-09-11 Texas Instruments, Incorporated Method and apparatus for real-time wafer temperature measurement using infrared pyrometry in advanced lamp-heated rapid thermal processors
EP0381253A1 (en) * 1989-01-02 1990-08-08 Interuniversitair Microelektronica Centrum Vzw Apparatus and method for processing one or more wafers of material

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 10, no. 290 (P-503)(2346) 2 October 1986 & JP,A,61 110 018 ( CHINO WORKS LTD ) 28 May 1986 *
PATENT ABSTRACTS OF JAPAN vol. 11, no. 31 (E-475)9 September 1986 & JP,A,61 198 735 ( FUJITSU LTD ) *
PATENT ABSTRACTS OF JAPAN vol. 12, no. 273 (E-639)3 September 1988 & JP,A,63 054 719 ( NEC CORP. ) *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993010426A1 (en) * 1991-11-22 1993-05-27 Secretary Of State For Trade And Industry Temperature measuring apparatus
US5444815A (en) * 1993-12-16 1995-08-22 Texas Instruments Incorporated Multi-zone lamp interference correction system
DE4414391A1 (en) * 1994-04-26 1995-11-02 Ast Elektronik Gmbh Method and device for wave vector selective pyrometry in rapid heating systems
US5628564A (en) * 1994-04-26 1997-05-13 Ast Elekronik Gmbh Method and apparatus for wavevector selective pyrometry in rapid thermal processing systems
DE4414391C2 (en) * 1994-04-26 2001-02-01 Steag Rtp Systems Gmbh Method for wave vector selective pyrometry in rapid heating systems
DE19534440A1 (en) * 1995-09-16 1997-03-20 Bergmann Hans Wilhelm Contactless measurement of temperature of coloured material

Also Published As

Publication number Publication date
EP0519033A1 (en) 1992-12-23
JPH05507356A (en) 1993-10-21
KR920704108A (en) 1992-12-19
NL9100018A (en) 1992-08-03

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