JP2007218591A - Hybrid-type surface thermometer, apparatus, and method for measuring temperature distribution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hybrid-type surface thermometer, capable of generating synergistic effects by combining advantages of a contact type approach, such as a thermocouple and advantages of a noncontact type approach, such as temperature measurement by radiation and simultaneously overcoming weak points of both approaches. <P>SOLUTION: The hybrid-type surface thermometer measures the surface temperature of an object to be measured by pressing a membranous metal to the object to be measured by a prescribed pressure into contact and measuring radiance from the back surface of the membranous metal with an optical sensor. A rod-like light-transmitting body, such as sapphire, is further arranged in the immediate vicinity of the object to be measured. Then radiation from the object to be measured is made to transmit through the rod-like light-transmitting body and detected with the optical sensor. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention combines the advantages of a contact-type surface temperature measurement method such as a thermocouple with the advantages of a non-contact-type surface temperature measurement method such as radiation temperature measurement, and at the same time demonstrates the weaknesses of both. The present invention relates to a new hybrid type surface thermometer, temperature distribution measuring apparatus and measuring method which have been overcome. Measurement is performed by pressing a thin film metal material with particularly good thermal conductivity against the object to be measured to reveal a thermal equilibrium state, and measuring the back surface of the thin film metal material that is not in contact with the object to be measured by a radiation temperature measurement method. The present invention provides a hybrid surface thermometer, a temperature distribution measuring device, and a measuring method capable of measuring the true temperature of an object.

  Temperature is one of the most basic and important physical quantities in various fields. For this reason, various temperature measurement methods exist, and research and development are still in progress. An overview of measurement objects limited to measuring the surface temperature of an object is roughly classified as a thermocouple, where the object is thermally contacted by welding or the like, and the temperature is measured by measuring its thermoelectromotive force, so-called contact. There are two types of temperature measurement methods: a radiation temperature measurement method in which a temperature is measured by detecting an electromagnetic wave emitted corresponding to the temperature of an object, a so-called non-contact temperature measurement method.

  The former is basically required to be welded to the object, so it is difficult to apply to objects that are difficult to weld or to travel, damage the object for welding, environment And the problem of deterioration of the thermocouple itself due to aging. On the other hand, the latter radiation temperature measurement method causes a critical temperature measurement error when the emissivity of the surface of the measurement object changes. A measurement object having a constant emissivity is extremely rare in practice, and in order to apply the radiation temperature measurement method, basically, a measure for correcting the emissivity by some method is necessary.

Non-Patent Document 1 below discloses a method of measuring temperature by using a thermocouple and indirectly contacting the measurement object via a thin film metal, instead of welding the thermocouple directly to the measurement object. Yes. That is, it is described that measurement accuracy is improved when a thin film metal with a thermocouple fixed is brought into contact with a measurement object and temperature is measured. However, it cannot be easily used for measuring the surface temperature of a silicon semiconductor wafer or the like, and has the disadvantage of temperature measurement using the thermocouple described above.
D. Yakob, HeatTransfer, Vol.II, John Wiley & Sons (1965) P.151-P.152

Furthermore, as an adapter for a non-contact thermometer for measuring low emissivity, a portion of the convex cross section that crosses the optical axis is attached to the tip of the non-contact thermometer with a thin synthetic resin infrared radiation member. A surface thermometer having a configuration is disclosed in Patent Document 1, and an internal thermometer that measures the inside of a measurement target is disclosed in Patent Document 2. Although these have a relatively simple configuration, they cannot be easily used for measuring the surface temperature of a silicon semiconductor wafer or the like.
Japanese Patent Laid-Open No. 10-9958 Japanese Patent Laid-Open No. 10-281878

The present invention combines the advantages of a contact-type method such as a thermocouple with the advantages of a non-contact method such as radiation temperature measurement, and at the same time provides a new hybrid surface thermometer that overcomes the weaknesses of both. The purpose is to provide.

  In addition, a new thin-film metal material with good thermal conductivity is brought into contact with the object to be measured to reveal the thermal equilibrium state, and the back surface of the thin-film metal material that is not in contact with the object to be measured is measured using a radiation temperature measurement method. An object is to provide a hybrid surface thermometer. It is another object of the present invention to provide a new hybrid surface thermometer that measures the true temperature by a radiation temperature measurement method that does not depend on variation in emissivity by processing the back surface of the thin film metal material with high emissivity.

  Furthermore, by combining the surface thermometer part using thin film metal that is in contact with the object to be measured and the radiometer part not being used, not only the temperature of the object to be measured but also the emissivity of the object to be measured, which is a weak point of the radiation thermometry An object of the present invention is to provide a new hybrid surface thermometer that can be used.

  It is another object of the present invention to provide a new hybrid surface thermometer that is particularly effective for measuring the temperature of a semiconductor wafer or the like where it is difficult to weld a thermocouple or the like to the surface.

  It is another object of the present invention to provide a new hybrid surface thermometer that can be applied in a wide range from a low temperature near normal temperature to a high temperature exceeding 2000 ° C. Furthermore, not only local point measurement such as single point measurement of a minute surface with a diameter of 1 mm or less, but also combination with an optical fiber or a light transmission rod, multiple points can be measured simultaneously, and high added value. It is an object of the present invention to provide a new hybrid surface thermometer, temperature distribution measuring apparatus and measuring method that can be used in many fields.

  In order to solve the above-mentioned problems and objects, in the hybrid surface thermometer according to claim 1 of the present invention, the thin film metal is brought into pressure contact with the measurement object at a desired pressure, and the back surface of the thin film metal not in contact with the measurement object. The surface temperature of the measurement object is measured by measuring the radiance from the optical sensor with an optical sensor.

In the hybrid surface thermometer according to claims 2 and 3 of the present invention, a rod-shaped light transmission of sapphire, quartz, calcium fluoride (CaF ₂ ), barium fluoride (BaF ₂ ) or the like is provided in the immediate vicinity of the measurement object. A body is installed, and radiation from the back surface that is not in contact with the thin film metal measurement object is transmitted through the rod-shaped light transmission body, and is detected by an optical sensor. The hybrid surface thermometer according to claim 4 of the present invention is characterized in that the dependence of the emissivity is reduced by processing the back surface of the thin film metal that is not in contact with the object to be measured with high emissivity.

  Furthermore, the hybrid surface thermometer according to claim 5 of the present invention has a compensation means for compensating the temperature of the thin film metal which is lowered by the thermal contact resistance generated when the thin film metal contacts the measurement object. The surface temperature of the measurement object is compensated for measurement.

Furthermore, in the temperature distribution measuring apparatus using a hybrid surface thermometer according to claim 6 of the present invention, one or a plurality of hybrid surface thermometers described in claims 1 to 5 are arranged at predetermined intervals. The temperature distribution of the measurement object is measured.

  Furthermore, in the measuring method and the hybrid surface thermometer according to claim 7 of the present invention, the surface temperature of the object to be measured is measured by one hybrid surface thermometer described in claims 1 to 5, and the thin film metal is also measured. The surface temperature and emissivity of the measurement object can be measured by measuring the radiance of the same measurement region of the measurement object with a radiometer using a second optical sensor prepared separately. .

  Further, in the measurement method and the hybrid surface thermometer according to claim 8 of the present invention, the temperature and polarization of the object to be measured can be obtained by attaching a polarizer to the measurement method of claim 7 and the radiometer of the hybrid surface thermometer. The emissivity can be measured.

  Further, in the measurement method and the hybrid surface thermometer according to claim 9 of the present invention, the spectroscope is attached before the measurement method according to claim 7 and the radiometer of the hybrid surface thermometer, so that The spectral emissivity can be measured.

  The hybrid surface thermometer and measurement method according to the present invention combine the advantages of a contact method such as a thermocouple with the advantages of a non-contact method such as radiation temperature measurement, and at the same time exhibit a synergistic effect. New surface temperature measurement overcoming the weak points is possible. In other words, it is possible to bring a thin film metal material with good thermal conductivity into contact with the object to be measured to reveal the thermal equilibrium state, and to accurately measure the true temperature on the back surface by radiation thermometry, which damages the object to be measured. In the measurement temperature range, by selecting a thin film metal material, it is possible to accurately measure the true temperature over a wide range from a low temperature near normal temperature to a high temperature exceeding 2000 ° C.

  Furthermore, in the hybrid surface thermometer and measurement method according to the present invention, there is no need to weld a thermocouple or the like to the surface to be measured or to attach a black body tape or black body paint to the object to be measured. It is easy and easy to operate. In addition, it can be a particularly effective temperature measurement technique for a sample such as a silicon semiconductor wafer in which it is extremely difficult to weld a thermocouple to the sample surface. It is also effective as a so-called in-situ temperature measurement method during the manufacturing process. This is particularly effective for measuring the temperature of a semiconductor wafer or the like.

  Further, in the hybrid surface thermometer and measurement method according to the present invention, since a thin metal material is used, the function of the thermocouple wire is not deteriorated without the deterioration of the function, that is, the change in electromotive force, unlike the thermocouple. Since no conduction loss is involved, it is easy to realize a rapid thermal equilibrium state with the measurement object, and the true temperature of the measurement object can be accurately measured.

Furthermore, in the hybrid surface thermometer according to the second and third aspects of the present invention, a rod-shaped light transmission body such as a sapphire rod, a quartz rod, a calcium fluoride (CaF ₂ ) rod, a barium fluoride (BaF ₂ ) rod or the like. Since the radiance from the thin film metal is transmitted through this light transmitting body and detected by the optical sensor, the surface thermometer can be made compact, and the surface temperature of a minute surface can be measured.

  Furthermore, in the hybrid surface thermometer according to the present invention of claim 4, since the back surface not in contact with the thin film metal measurement object is processed with high emissivity, the influence of fluctuation of the emissivity of the thin film metal can be reduced. It is possible to accurately measure the true temperature of the measurement object.

  Further, the hybrid surface thermometer according to the present invention of claim 5 has compensation means for compensating the temperature of the thin film metal which is lowered by the thermal contact resistance generated when the thin film metal contacts the measurement object. Since the surface temperature is compensated by the measurement, the true temperature of the measurement object can be accurately measured even if thermal contact resistance may occur.

  Furthermore, in the temperature distribution measuring apparatus according to the present invention of claim 6, a plurality of the hybrid surface thermometers of the present invention are arranged at a predetermined interval, and multiple points on a minute surface can be measured simultaneously. It is possible to accurately measure the temperature distribution. As a high value-added temperature measuring instrument that can measure not only one point on a minute surface with a diameter of 1 mm or less but also multiple points simultaneously by combining with an optical fiber or a light transmitting rod, etc. in many fields. Can be used.

Furthermore, the measurement method and the hybrid surface thermometer according to the present invention of claim 7 to 9 have a hybrid surface thermometer and a radiometer, and not only the surface temperature of the same measurement region to be measured but also the emissivity and polarization. It is possible to measure emissivity and spectral emissivity almost simultaneously. Furthermore, for example, even if the emissivity fluctuates due to an oxide film (SiO ₂ ) grown on the silicon semiconductor wafer surface, the temperature and emissivity can be measured simultaneously with this measurement method and the hybrid surface thermometer. It is also possible to investigate the relationship between and emissivity in the process.

Before describing the best mode for carrying out the present invention, the basic principle of a hybrid surface thermometer according to the present invention will be described below with reference to FIG. The hybrid surface thermometer according to the present invention brings a thin film metal material having a good thermal conductivity into contact with the surface of the object to be measured to reveal a thermal equilibrium state, and from the back surface not in contact with the object of measurement of the thin film metal material. The radiance is measured by an optical sensor, and the surface temperature of the measurement object is measured. In FIG. 1, 1 is a measurement object such as a silicon semiconductor wafer, 2 is a thin film metal, and 3 is a radiometer acting as an optical sensor. The thin film metal 2 is usually 5 mm wide, 10 mm long and about 20 to 50 μm thick. When the thin film metal 2 is brought into pressure contact with the measurement object 1, the measurement object 1 and the thin film metal 2 are ideally in thermal equilibrium. It becomes a state and becomes almost the same temperature. Therefore, by measuring the luminance of the back surface 2B opposite to the contact surface 2A with the measurement object 1 of the thin film metal 2 with the radiometer 3, the temperature of the measurement object 1 can be obtained indirectly. The present invention is based on this technique. At this time, it is preferable that the emissivity of the back surface 2B of the thin film metal 2 is stable and known, or artificially set to a high emissivity state. In such a case, more accurate temperature measurement is possible. Become.
The best mode for carrying out the present invention will be described below with reference to the drawings.
In the following embodiment, an embodiment implemented as a surface thermometer for measuring the surface temperature of a silicon semiconductor wafer will be described.

  FIG. 2 is a basic configuration diagram of an embodiment of a hybrid surface thermometer according to the present invention. A thin film metal 12 brought into contact with a measuring object 11 which is a silicon semiconductor wafer is supported by a quartz pipe 13 having excellent heat insulation. ing. The sapphire rod 14 is provided in the holder 15 so that the tip portion is closest to the thin film metal 12, and the radiation from the thin film metal 12 is transmitted through the sapphire rod 14. As shown in FIG. 2, the holder 15 holds the end of the sapphire rod 14 on which the thin film metal 12 is not attached. Further, the radiance from the thin film metal 12 is detected by the optical sensor 17 through the optical fiber 16 connected to the other end of the sapphire rod 14. The detected radiance is corrected by the signal processing unit 18 as necessary. As will be described later, signal processing is performed, a display signal for the surface temperature is formed, the surface temperature is displayed on a display not shown, and is recorded by a printer not shown. A thin film metal 12, a quartz pipe 13, a sapphire rod 14, and a holder 15 for holding them constitute a sensor unit 19. Further, the drive unit 20 is connected to the holder 15, and the sensor unit 19 is moved by a predetermined distance in the vertical direction in FIG. 2 by the drive unit 20 (the state in which the thin film metal 12 is pressed and contacted with the measurement object 11, as shown in FIG. 2. It is provided to be movable only in a state of being separated from the measurement object 11 being measured. The thin film metal 12 is supported at the tip of the sensor unit 19 by a quartz pipe 13 at a predetermined distance from the tip of the sapphire rod 14. In this embodiment, the thin-film metal 12 is supported by using the quartz pipe 13, but the thin-film metal 12 can also be supported by using a ceramic heat insulating material in addition to the quartz pipe.

When the thickness of the thin film metal 12 brought into contact with the measurement object 11 is about 20 to 50 μm, there is almost no temperature difference (within 0.1 K) between the measurement object 11 and the thin film metal 12 in an ideal contact state. Depending on the degree of surface roughness of the surface to be measured and the thin film metal surface, thermal contact resistance may occur. In this case, a temperature gap is generated between the surface temperature of the measuring object 11 and the temperature of the thin film metal 12. As a result of experiments by the present inventors, it has been found that it is necessary to press the thin film metal 12 against the measurement object 11 with a pressure of 5 × 10 ³ Pa or more in order to reduce the thermal contact resistance.

  The thin film metal 12 at the sensor tip is typically (preferably) a thin metal material having a width of 5 mm, a length of 10 mm, and a thickness of about 20 to 50 μm, such as gold, platinum, iridium and other precious metals, aluminum, stainless steel, Base metals or alloys such as Inconel, titanium, tungsten, and hastelloy can be used. The selection of the material is mainly used depending on the temperature region. The advantage of this thin metal plate is that it does not involve functional deterioration like a thermocouple, that is, no change in electromotive force and does not involve heat conduction loss of the thermocouple element. It is easy to realize a stable thermal equilibrium state.

  Furthermore, the optical sensor 17 detects the radiance from the back surface 12B of the thin film metal 12, that is, the surface 12B opposite to the surface 12A in contact with the measurement object 11. In the case of noble metals such as gold and platinum, the optical constant as a physical property value is extremely stable and known, so the emissivity can also be regarded as extremely stable and known. Can be requested. Alternatively, for metals such as aluminum, stainless steel, inconel, titanium, and hastelloy, the surface is roughened by fine processing to increase the effective emissivity, or the surface is coated with a pseudo black body paint, which is about 0.95. By making the emissivity high, temperature measurement close to the true temperature can be realized. In the case of gold or platinum, a high emissivity state can be similarly obtained by chemical treatment of gold black or platinum black, and true temperature measurement can be realized without emissivity correction. Thus, it can be said that the correction of the emissivity may be performed if necessary.

  Furthermore, by selecting the thin film metal material of the thin film metal 12 as described above, it is possible to measure the true temperature of the measurement object 11 in the measurement temperature range from room temperature to a high temperature of about 2000K. That is, a high thermal conductivity thin film metal such as aluminum from room temperature to about 600K, and various metals or alloys such as stainless steel plate, inconel, titanium, hastelloy, etc. can be selected and used in the medium to high temperature range from about 600K to about 1300K. In addition, when it is necessary to avoid oxidation due to heating, a noble metal such as platinum or gold can be used. Further, in a high temperature range from about 1300K to 2000K, a metal that can withstand high temperatures such as iridium can be used. Further, as the heat insulating material that supports these thin film metals 12, quartz or a high-temperature ceramic heat insulating material can be used. In the temperature measurement in a vacuum as a special environment, a thin film of tungsten can be used in addition to the above materials.

Table 1 shows a thermal contact resistance of 60 × 10 ⁻⁶ [m ² / W · K] (where W is watts, K) using a literature value with a silicon semiconductor wafer having a flat and specular surface as a measurement object 11. Represents Kelvin.) When using a thin film alloy Hastelloy having a thickness of 20 μm and a thermal conductivity of 70 W / m ² K as the thin film metal 12, the emissivity of the radiance measurement surface is 0.95 The measurement result of the hybrid surface thermometer by simulation is shown. The surface temperature of the silicon semiconductor wafer in the left column of Table 1 is assumed to be 320K to 1100K, and when the heat is transferred to Hastelloy in contact with the wafer surface, the surface temperature of the back surface of the Hastelloy, that is, the temperature of the thin film metal 12 is simulated. The hour value is described in the middle column. The right column shows the difference between the assumed surface temperature of the silicon semiconductor wafer (measurement object 11) and the temperature of the thin film metal 12. (This difference can be judged to be mostly an error caused by thermal contact resistance.) As can be seen from Table 1, in the relatively low temperature range where the surface temperature of the silicon semiconductor wafer to be measured is 400K or less, the hybrid surface thermometer is used. The temperature measurement error remains below 1K, but the error increases as the temperature increases. Since this temperature error always occurs under certain conditions, it can be considered as a systematic error.

  Table 2 shows the experimental results of actually measuring the surface temperature of the silicon semiconductor wafer using the hybrid surface thermometer embodiment of the present invention shown in FIG. The surface temperature of the silicon semiconductor wafer on the left side in Table 2 indicates the surface temperature obtained by actually measuring the surface temperature of the silicon semiconductor wafer by another method in order to confirm the operation of the hybrid surface thermometer according to the present invention. Another method here is to apply a black paint that becomes a pseudo black body on the surface of the silicon semiconductor wafer so that the emissivity of the wafer is about 0.95, and another (conventional) thermometer to measure the silicon semiconductor wafer. This is a method of using the radiation thermometer output after measuring the surface temperature of the silicon semiconductor wafer and correcting it with an emissivity of 0.95, and this output is described in the column on the left side of Table 2 as the true surface temperature of the silicon semiconductor wafer. On the other hand, the temperature before the correction processing by the signal processing unit 18 measured in the embodiment shown in FIG. 2 of the hybrid surface thermometer according to the present invention is described in the center column of Table 2. The right column of Table 2 shows the surface temperature of the silicon semiconductor wafer measured by another method (left column) and the temperature before correction of the thin film metal 12 measured by the hybrid surface thermometer according to the present invention (center column). Showing the difference. For example, when the surface temperature of the silicon semiconductor wafer in the left column is 500K, the indication of the hybrid surface thermometer in the middle column is 497.5 ± 0.7K, but this is centered on 497.5K. It shows that it varies by ± 0.7K. That is, as shown in the temperature difference in the right column, the systematic error is 2.5K, and the accidental error is ± 0.7K. Similarly, when the surface temperature of the silicon semiconductor wafer (left column) is 1200K, the temperature difference in the right column is 10.1 ± 0.9K, of which 10.1K is a systematic error, and the ± 0.9K portion Indicates a true random error, which is called an accidental error, and this is a temperature error in the original sense.

Therefore, as a practical usage of the hybrid type surface thermometer of the present invention, first, the temperature of the thin film metal is measured by an optical sensor, and an approximate systematic error is assumed from the displayed value and corrected by the signal processing unit 18. . For example, if a thin film metal is measured at 1080K, assuming that the systematic error is about 8K, 8K is added to 1080K, and 1088K is corrected by the signal processing unit to obtain the true surface temperature of the silicon semiconductor wafer. In that case, it is considered that it includes a chance error of about ± 0.8K. Here, the pressure applied to the measuring object 11 which is a silicon semiconductor wafer when the thin film metal 12 is in contact is set to 0.02 MPa. As a result of experiments by the present inventor, it has been found that a pressure in the range of 5 × 10 ³ Pa or more and a measurement target such as a silicon semiconductor wafer is not damaged is necessary. The systematic temperature error shows the same result as the simulation result. Further, the accidental measurement error in each temperature range is suppressed to ± 1K or less.

  As described in detail above, the signal processing of the following procedure is performed by the signal processing unit 18 of FIG. 2 as signal processing of the hybrid surface thermometer from the simulation and actual measurement results. That is, when the contact pressure of the tip of the hybrid surface thermometer (thin film metal 12) with respect to the measurement object 11 is predetermined and the radiance is detected by the optical sensor 17, the temperature is converted to the temperature. If a systematic temperature error is added, the correct temperature of the measuring object 11 can be obtained. The systematic temperature error can be determined in each temperature region as described above if the material of the measurement object 11 and its surface roughness are known. Thus, by the signal processing, the final temperature measurement error obtained can always be ± 1K or less in the temperature range exceeding 1000K.

  FIG. 3 is a basic configuration diagram of another embodiment of the hybrid surface thermometer according to the present invention. Reference numeral 21 denotes a measurement object such as a silicon semiconductor wafer, and reference numeral 22 denotes a thin film metal supported by a heat insulating material holder 24. As the heat insulating material holder 24 for supporting the thin film metal 22, a ceramic heat insulating material can be used in addition to the quartz pipe. In this embodiment, the radiance from the thin film metal 22 is directly applied to the optical sensor 27 through the optical system such as the lens 23 without using the sapphire rod 14 and the optical fiber 16 used in the first embodiment of FIG. Thereafter, the signal processing unit 28 performs signal processing in the same manner as in the first embodiment, as in the first embodiment shown in FIG. Reference numeral 24 denotes a heat insulating material holder for holding the lens 23 and the thin film metal 22, as in the first embodiment of FIG. 2, by a drive unit 30 in the vertical direction in FIG. 3 (the thin film metal shown in FIG. 3). 22 is provided so as to be movable only between a state where it is pressed against the measuring object 21 and a state where it is separated from the measuring object 21). Other structural actions are the same as those of the first embodiment shown in FIG.

  Furthermore, the hybrid surface thermometer according to the present invention can be applied as a means for measuring not only the surface temperature of the measurement object but also the emissivity of the measurement object almost simultaneously. FIG. 4 is a basic configuration diagram of a third embodiment of the hybrid surface thermometer according to the present invention. The hybrid surface thermometer of the first embodiment using a combination of the sapphire rod and the optical fiber shown in FIG. 2 is used. It is a conceptual diagram of the simultaneous temperature and emissivity measuring apparatus. The same components as those in the first embodiment shown in FIG.

As shown in FIG. 4, the hybrid type surface temperature of the first embodiment including the thin film metal 12, the quartz pipe 13, the sapphire rod 14, the holder 15, the optical fiber 16, the optical sensor 17, the signal processing unit 18, and the driving unit 20. The measurement unit 11 is the same as the measurement target 11, and the radiometer unit 44 including the second sapphire rod 40, the second optical fiber 41, the second optical sensor 42, and the second signal processing unit 43 not having a thin film metal. Install to see the area. The former, that is, the hybrid-type surface thermometer unit 45 is moved up and down by the drive unit 20 as described above to intermittently contact and press the measurement target 11 to correct the surface temperature T of the measurement target 11 by the signal processing described above. And measure accurately. As the latter back and forth, i.e. sapphire rod 40, optical fiber 41, the optical sensor 42, and the radiance _{E = εL λ. B (T} ) from the same region of the measurement target 11 by the radiometer unit 44 and a signal processing unit 43 taking measurement. Here, L _{λ .b} (T) is a spectral blackbody radiance at temperature T and represents a signal output detected by the optical sensor 42 via the sapphire rod 40 and the optical fiber 41. ε is the spectral emissivity of the measurement object 11 corresponding to the detection wavelength of the optical sensor 42. Since the black body radiance output E _b = L _λ . _B (T) corresponding to this radiometer is obtained by the temperature T previously measured by the hybrid surface thermometer, the emissivity ε of the measurement object is the two signals E And E _b are obtained by the following mathematical formula 1.

  In the third embodiment shown in FIG. 4, a spectroscope is installed in front of the optical sensor that detects the radiance E, so that the emissivity for each wavelength, that is, the spectral emissivity can be improved and modified. . Furthermore, if a polarizer is installed on the front surface of the sapphire rod 40, and this radiometer is measured at an angle of θ = 30 ° or more from the surface normal direction of the measurement object, p-polarized emissivity, or It is also possible to measure s-polarized emissivity. If the spectral emissivity and polarized emissivity can be measured in such a wide wavelength band, not only temperature measurement but also surface information related to the emissivity of the object to be measured, such as oxide film characteristics (thickness, etc.) in-situ There is a possibility that it can be grasped, and the use is expanded.

  FIG. 5 is a graph showing the results of simultaneous measurement of spectral emissivity and surface temperature at a wavelength l = 0.9 mm according to the third embodiment of the hybrid surface thermometer of the present invention shown in FIG. A stainless steel plate (SUS430) is heated as an object to be measured in the atmosphere, and in the temperature rising process, the temperature is measured by a hybrid surface thermometer configured with Hastelloy as a thin film metal 12, and intermittently based on the above-described equation (1). The emissivity is obtained. It can be observed that the emissivity increases with increasing temperature, but then starts decreasing. This is because the emissivity increases with the generation of an oxide film on the surface of the thin film metal 12 as the temperature rises. However, when the oxide film thickness increases to some extent, multiple reflections of radiation occur between the surface of the measurement object 11 and the oxide film surface. It shows the emissivity inversion phenomenon caused by the interference effect. Since the hybrid surface thermometer according to the present invention can simultaneously measure the emissivity and the temperature as described above, it can provide means for grasping such a phenomenon in the process. As described above, since the emissivity can be measured at the same time as the temperature in-situ, it is possible to provide a powerful new means for grasping the surface phenomenon of the measurement object related to the emissivity. Since this hybrid surface thermometer has such a possibility, it can be a novel sensor that exceeds the role as a temperature measurement sensor.

  Furthermore, the hybrid surface thermometer according to the present invention can measure not only the surface temperature of the measurement target but also the temperature distribution of the measurement target by arranging a plurality of the hybrid surface thermometers at predetermined intervals. FIG. 6 shows a sensor array in which twelve sensor units 19 of the hybrid surface thermometer embodiment shown in FIG. 2 are arranged at a predetermined interval. Each sensor portion 19 is constituted by a thin film metal 12, a quartz pipe 13, a sapphire rod 14, and a holder 15 as in the embodiment of FIG. The optical fiber 16 and the optical sensor 17 shown in FIG. 2 are not shown for simplicity, but are provided in the same manner as the embodiment shown in FIG. That is, it shows a basic method of measuring the temperature distribution of the measurement object (sample surface) 11 by arranging a large number of sensor tip portions of the hybrid surface thermometer in an array.

Furthermore, the hybrid surface thermometer, the temperature distribution measuring apparatus and the measuring method according to the present invention can be used not only in the atmosphere, but also by measuring the temperature of the sample in the vacuum apparatus or the emissivity by changing the appropriate structure. It can also be used for measurement. The hybrid surface thermometer, temperature distribution measuring apparatus, and measuring method according to the present invention are particularly effective for a sample that is extremely difficult to weld a thermocouple to a measurement target (sample surface) such as a silicon semiconductor wafer. Temperature measurement technology. It can also be used as a so-called in-situ temperature measurement method during the manufacturing process. For example, even if the emissivity fluctuates greatly due to an oxide film (SiO ₂ ) grown on the silicon semiconductor wafer surface, the hybrid surface thermometer according to the present invention can simultaneously measure temperature and emissivity. And the relationship between emissivity in the process.

It is the figure which showed the basic principle of the hybrid type surface thermometer which concerns on this invention. It is a basic lineblock diagram of the 1st example of a hybrid type surface thermometer concerning the present invention. It is a basic composition figure of the 2nd example of the hybrid type surface thermometer concerning the present invention. It is a basic block diagram of 3rd Example of the hybrid surface thermometer which concerns on this invention which measures surface temperature and an emissivity simultaneously. 6 is a graph showing the results of simultaneous measurement of emissivity and surface temperature according to a third example of the hybrid surface thermometer of the present invention. It is a basic composition figure of the sensor array of the temperature distribution measuring device using the sensor part of the 1st example of the hybrid type surface thermometer concerning the present invention.

Explanation of symbols

1, 11, 21 Measuring object 2, 12, 22 Thin film metal 3 Radiometer (optical sensor)
13 Quartz pipe 14, 40 Sapphire rod 15, 24 Holder 16, 41 Optical fiber 17, 27, 42 Optical sensor 18, 28, 43 Signal processing unit 19 Sensor unit 20, 30 Drive unit 23 Lens

Claims (9)

  Measuring the surface temperature of the measurement object by bringing the thin film metal into contact with the measurement object at a desired pressure and measuring the radiance from the back surface of the thin film metal not in contact with the measurement object with an optical sensor. Features a hybrid surface thermometer.   2. The hybrid surface thermometer according to claim 1, wherein a rod-shaped light transmitting body is installed on the back side of the thin film metal so as to be close to the measurement object, and the thin film is passed through the rod-shaped light transmitting body. A hybrid surface thermometer characterized in that the surface temperature of the object to be measured is measured by transmitting radiance from a metal and detecting it with an optical sensor. 3. The hybrid surface thermometer according to claim 2, wherein the rod-shaped light transmitting body is one of a sapphire rod, a quartz rod, a calcium fluoride (CaF ₂ ) rod, a barium fluoride (BaF ₂ ) rod, or A hybrid surface thermometer characterized by the use of a plurality.   4. The hybrid surface thermometer according to claim 3, wherein the back surface of the thin film metal that is not in contact with the object to be measured is processed with high emissivity to reduce dependence due to a difference in emissivity. Hybrid surface thermometer.   2. The hybrid surface thermometer according to claim 1, further comprising compensation means for compensating for the temperature of the thin film metal which is lowered by a thermal contact resistance generated when the thin film metal comes into contact with a measurement object. A hybrid surface thermometer characterized in that the surface temperature of the object to be measured is compensated for by the measurement.   A temperature by a hybrid surface thermometer, wherein one or a plurality of hybrid surface thermometers according to claim 1 are arranged at a predetermined interval to measure a temperature distribution of the measurement object. Distribution measuring device.   One hybrid surface thermometer according to claim 1 and a radiometer for measuring emissivity by a second photosensor not having a thin film metal, and having the same measurement region of the measurement object A measurement method and a hybrid surface thermometer, wherein the surface temperature and emissivity of the measurement object are measured by measuring radiance.   A measurement method and a hybrid surface thermometer according to claim 7, wherein a surface temperature and a polarized emissivity of the measurement object are measured by attaching a polarizer to the radiometer, and Hybrid surface thermometer.   The measurement method and the hybrid surface thermometer according to claim 7, wherein a surface temperature and a spectral emissivity of the measurement object are simultaneously measured by attaching a spectroscope in front of the radiometer. Measuring method and hybrid surface thermometer.

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