Temperature measurement method, temperature measurement device, and optical heating device

Abstract

To provide a temperature measurement method, a temperature measurement apparatus, and a light heating apparatus which can perform light irradiation to a principal surface, of a substrate, to be subjected to heating treatment, with an intensity required for heat treating, and also can measure surface temperature of a treated substrate to be subjected to heating treatment with higher accuracy.SOLUTION: There is provided a method for measuring temperature of a substrate in which a pattern is formed on a first principal surface. The method includes: a step (A) of disposing a substrate such that a first temperature measuring device two-dimensionally measuring temperature can receive infrared light emitted from a first field of measurement on a second principal surface opposite the first principal surface of the substrate; a step (B) of measuring a temperature distribution of the first field of measurement on the second principal surface by the first temperature measuring device; a step (C) of measuring temperature of a second field of measurement including a material with known emissivity on the surface of the substrate by the second temperature measuring device; and a step (D) of correcting each value of the temperature distribution of the first field of measurement on the basis of the temperature distribution of the first field of measurement measured by the first temperature measuring device and the temperature of the second field of measurement measured by the second temperature measuring device.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a temperature measurement method, a temperature measurement device, and an optical heating device. [Background technology]

[0002] In semiconductor manufacturing processes, various heat treatments such as film formation, oxidation / diffusion, modification, and annealing are performed on substrates to be processed, such as semiconductor wafers. These treatments often employ a heat treatment method using light irradiation, which allows for non-contact treatment. For example, Patent Document 1 listed below discloses a light heating device that uses an LED as a heating light source.

[0003] Furthermore, in the heat treatment process of semiconductor wafers and the like, uniform heat treatment is required across the entire substrate from the viewpoint of improving yield, etc., and a method of controlling the intensity of emitted light while checking the surface temperature of the semiconductor wafer is adopted. For example, Patent Document 2 listed below discloses an apparatus equipped with a thermo camera that two-dimensionally measures the temperature of the main surface (hereinafter referred to as the "first main surface") on which a pattern of a semiconductor wafer is formed, and a radiation thermometer that measures the temperature of the back main surface. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-009927 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-185898 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the present inventors have conducted extensive research into optical heating devices for heat-treating substrates such as semiconductor wafers and glass substrates, and have found that the following problems exist. These problems will be explained below with reference to the drawings.

[0006] In the heat treatment of a substrate to be processed, it is necessary to minimize the thermal history (also called "thermal budget"), which is the history of temperature changes that the substrate to be processed experiences, in order to suppress deformation of the substrate to be processed and fluctuations in the characteristics of elements and patterns formed on the substrate to be processed. For this reason, it is preferable that the optical heating device be configured so that heating light is irradiated onto the first main surface of the substrate to be processed.

[0007] Fig. 11 is a diagram schematically showing one configuration example of a light heating device 100 that emits heating light toward the first main surface W1a of the substrate W1 to be processed, and Fig. 12 is a diagram of the light heating device 100 of Fig. 11 as viewed from the +Z side. As shown in Figs. 11 and 12, the light heating device 100 includes an LED substrate 101b on which LED elements 101a are mounted, and a thermal camera 102. The area indicated by the dashed dotted line in Fig. 11 schematically shows the observation area of the thermal camera 102.

[0008] In the following description, the direction in which the LED substrate 101b and the substrate to be processed W1 face each other is referred to as the Z direction, and the plane perpendicular to the Z direction is referred to as the XY plane, as shown in Fig. 11. Note that the LED elements 101a are arranged in the same manner in the X and Y directions, so no distinction is made between the X and Y directions.

[0009] Also, when expressing a direction, if a distinction is made between positive and negative directions, the direction is written with a positive or negative sign, such as "+Z direction" and "-Z direction," and when a direction is expressed without distinguishing between positive and negative directions, it is simply written as "Z direction."

[0010] The optical heating device 100 is arranged so that the LED element 101a emits light toward the first main surface W1a of the substrate W1 to be processed, and the thermal camera 102 is arranged so as to measure the temperature of the first main surface W1a of the substrate W1 to be processed.

[0011] However, in this configuration, as shown in FIGS. 11 and 12, a hole 101h must be provided in the LED substrate 101b to allow the thermal camera 102 to observe the temperature of the entire first main surface W1a of the substrate to be processed W1.

[0012] As a result, the area in which the LED elements 101a can be arranged becomes narrower, and areas where no light is irradiated or where the intensity of irradiated light is extremely low are formed on the first main surface W1a of the substrate W1 to be processed, as shown in Fig. 11. This causes uneven heating on the substrate W1 to an extent that cannot be corrected by adjusting the brightness of the LED elements 101a, etc.

[0013] It is also possible to place the thermal camera 102 on the side of the substrate W1 to be processed, but if the thermal camera 102 is placed at an angle to the main surface of the substrate to be processed, large measurement errors may occur depending on the measurement position due to differences in perspective, etc.

[0014] In view of the above problems, the present invention aims to provide a temperature measurement method, a temperature measurement device, and an optical heating device that can irradiate light at the intensity required for the heat treatment onto the main surface of the substrate to be heat-treated, and that can measure the surface temperature of the substrate to be heat-treated with higher accuracy. [Means for solving the problem]

[0015] The temperature measurement method of the present invention includes: 1. A method for measuring a temperature of a substrate having a pattern formed on a first major surface, comprising: a step (A) of positioning the substrate so that a first temperature measuring device that observes infrared light radiated from the substrate and measures temperature two-dimensionally can receive infrared light radiated from a first measurement region on a second main surface of the substrate opposite to the first main surface; After the step (A), a step (B) of measuring a temperature distribution in the first measurement region on the second main surface by the first temperature measuring device; After the step (A), a step (C) is performed in which a second temperature measuring device having a higher temperature measurement accuracy and a narrower measurement range than the first temperature measuring device is used to observe infrared light emitted from the substrate and measure the temperature of a second measurement region on the surface of the substrate, the second measurement region containing a material having a known emissivity; After carrying out the steps (B) and (C), the method further comprises a step (D) of correcting each value of the temperature distribution of the first measurement area measured by the first temperature measuring device based on the temperature distribution of the first measurement area measured by the first temperature measuring device and the temperature of the second measurement area measured by the second temperature measuring device.

[0016] Here, "a material with a known emissivity" refers to, for example, a material for which a standard value generally used as a guideline for emissivity exists, or a material for which the emissivity has been measured separately in advance before the above-mentioned method is carried out. Furthermore, the measurement carried out in advance may be a measurement carried out in a device separate from the light heating device, or a measurement carried out within the light heating device immediately before the above-mentioned measurement method is carried out.

[0017] The wavelength ranges at which thermal cameras and radiation thermometers are sensitive vary slightly depending on the object being measured and the temperature range, but are generally set in the near-infrared to far-infrared wavelength range (e.g., 0.8 μm to 14 μm). In this specification, light within these wavelength ranges is collectively referred to as "infrared light."

[0018] The first temperature measuring device that measures the temperature of the main surface of the substrate two-dimensionally may be, for example, a measuring device that can measure the temperature distribution over a wide area with a single device, such as a thermocamera or a scanning radiation thermometer, or a measuring device in which multiple thermopiles or radiation thermometers are arranged in an array.

[0019] The second temperature measuring device has higher temperature measurement accuracy than these measuring devices and has a smaller overall measurement range, and for example, a radiation thermometer is used.

[0020] By using the above method, a wider area for arranging the light source unit can be secured compared to when the temperature of the first main surface of the substrate is measured with the first temperature measuring device. Also, by using the above method, a more accurate temperature distribution of the substrate can be obtained than when simply measuring with the first temperature measuring device.

[0021] The temperature measurement method is as follows: When the substrate is viewed in a direction perpendicular to the first main surface, the first measurement area and the second measurement area may overlap.

[0022] By using the above method, the correction value for correcting the temperature distribution is calculated by comparing temperatures at the same position, that is, at opposing positions on each main surface, and therefore the influence of temperature gradients on the substrate is suppressed in the correction of the temperature distribution.

[0023] In the above temperature measurement method, The step (C) may be a method of measuring the temperature of the second measurement region on the first main surface by the second temperature measuring device.

[0024] By using the above method, the temperature difference between the first main surface and the second main surface can be corrected, and the temperature distribution of the first main surface can be essentially obtained while acquiring the temperature distribution of the second main surface using the first temperature measuring device.

[0025] In the above temperature measurement method, The step (C) may be a method of measuring the temperature of the second measurement region including the alignment mark on the first main surface by the second temperature measuring device.

[0026] The term "alignment mark" as used herein refers to a mark for positioning in each processing step, such as a recess formed by cutting or etching, or a pattern of a predetermined shape, on the first main surface of the substrate. The formation method, shape, size, etc. of an alignment mark are generally determined depending on the reading mechanism. For this reason, alignment marks of the same material, shape, and size are formed on substrates to be processed. Therefore, by using the above method, measurement variations between substrates can be suppressed.

[0027] In the temperature measurement method, The step (C) may be a method in which the second temperature measuring device measures the temperature of the second measurement region on the first main surface where no pattern is formed.

[0028] By using the above method, the second temperature measuring device measures the temperature of the second measurement region of the same material (substrate material), and therefore, measurement variations between substrates are suppressed.

[0029] The temperature measurement method is as follows: a step (E) of setting an emissivity in a third temperature measuring device that measures the temperature of a third measurement area on the first main surface by observing infrared light emitted from the substrate, the third measurement area being different from the first measurement area and the second measurement area; and after the step (E), a step (F) of measuring the temperature of the third measurement area by the third temperature measuring device, In step (E), the emissivity set in the third temperature measuring device may be calculated based on the temperature distribution corrected in step (D) and the material on the first main surface of the substrate placed in the third measurement area.

[0030] By using the above method, the third temperature measuring device is set to a more appropriate emissivity depending on the pattern material and temperature of the third measurement area, and therefore, by using the above method, it is possible to more accurately measure the temperature at any position on the first main surface of the substrate.

[0031] Furthermore, by arranging a plurality of third temperature measuring devices and measuring the temperature in a part of the area in which the first main surface is divided into a plurality of zones as the third measurement area, zone control of the heat treatment can be performed.

[0032] The temperature measuring device of the present invention comprises: An apparatus for measuring the temperature of a substrate having a pattern formed on a first main surface, comprising: a first temperature measuring device that observes infrared light emitted from the substrate and two-dimensionally measures the temperature of a first measurement region on a second main surface of the substrate opposite to the first main surface; a second temperature measuring device, which has higher temperature measurement accuracy and a narrower measurement range than the first temperature measuring device, and which observes infrared light emitted from the substrate to measure the temperature of a second measurement region on the surface of the substrate, the second measurement region including a material with a known emissivity; The present invention is characterized by comprising a first calculation unit that corrects each value of the temperature distribution measured by the first temperature measuring device based on the temperature distribution of the first measurement area measured by the first temperature measuring device and the temperature of the second measurement area measured by the second temperature measuring device.

[0033] The above configuration ensures a wider area for arranging the light source unit compared to when the temperature of the first main surface of the substrate is measured with the first temperature measuring device. Furthermore, the above method provides a more accurate temperature distribution of the substrate than a temperature distribution measured simply with the first temperature measuring device.

[0034] In the above temperature measuring device, The second temperature measuring device may be disposed on the first main surface side of the substrate.

[0035] By using the above configuration, the temperature difference between the first main surface and the second main surface can be corrected, and the temperature distribution of the first main surface can be essentially obtained while acquiring the temperature distribution of the second main surface using the first temperature measuring device.

[0036] The temperature measuring device is a third temperature measuring device that measures the temperature of a third measurement area by observing infrared light emitted from the third measurement area, the third measurement area being different from the first measurement area and the second measurement area; a memory unit in which data on the material on the first main surface of the substrate placed in the third measurement area is stored; It may also be provided with a second calculation unit that calculates the emissivity to be set in the third temperature measuring device based on the temperature distribution of the substrate measured by the first temperature measuring device and the data of the material stored in the memory unit.

[0037] With the above configuration, the third temperature measuring device is set to a more appropriate emissivity depending on the material and temperature of the pattern in the third measurement area, and therefore, with the above method, it is possible to more accurately measure the temperature at any position on the first main surface of the substrate.

[0038] Furthermore, by arranging a plurality of third temperature measuring devices and measuring the temperature in a part of the area in which the first main surface is divided into a plurality of zones as the third measurement area, zone control of the heat treatment can be performed.

[0039] The light heating device of the present invention is The temperature measuring device; a chamber in which the substrate is housed; a support member for supporting the substrate within the chamber; a light source unit that emits light toward a first main surface of the substrate supported in the chamber, The first temperature measuring device and the second temperature measuring device are disposed outside the space sandwiched between the substrate and the light source unit.

[0040] In the above-mentioned light heating device, the chamber has a light-transmitting window formed on a wall surface facing each main surface of the substrate, the light-transmitting window allowing infrared light to pass therethrough; The temperature measuring device may be disposed outside the chamber and measure the temperature of the substrate through the light-transmitting window. [Effects of the Invention]

[0041] According to the present invention, a temperature measurement method, a temperature measurement device, and an optical heating device are realized that can irradiate light at the intensity required for the heat treatment onto the main surface of the substrate to be heat-treated, and can measure the surface temperature of the substrate to be heat-treated with higher accuracy. [Brief explanation of the drawings]

[0042] [Figure 1]1 is a schematic cross-sectional view of the configuration of an embodiment of a light heating device when viewed in the Y direction. [Figure 2] 2 is a view of the light heating device of FIG. 1 as seen from the +Z side. [Figure 3] 1 is a diagram of a substrate to be processed supported by a support member as viewed from the -Z side. [Figure 4] 1 is a diagram of a substrate to be processed supported by a support member as viewed from the +Z side. [Figure 5] 1 is a graph showing the relationship between infrared wavelength and emissivity at each temperature of silicon (Si). [Figure 6] 1 is a schematic cross-sectional view of the configuration of an embodiment of a light heating device when viewed in the Y direction. [Figure 7] 7 is a diagram of the light heating device of FIG. 6 as viewed from the +Z side. [Figure 8] 1 is a diagram of a substrate to be processed supported by a support member as viewed from the +Z side. [Figure 9] FIG. 10 is a schematic cross-sectional view of the configuration of another embodiment of the light heating device when viewed in the Y direction. [Figure 10] FIG. 10 is a schematic cross-sectional view of the configuration of another embodiment of the light heating device when viewed in the Y direction. [Figure 11] 1 is a diagram schematically illustrating an example of the configuration of a light heating device that emits heating light toward a first main surface of a substrate to be processed. [Figure 12] 12 is a diagram of the light heating device of FIG. 11 as viewed from the +Z side. DETAILED DESCRIPTION OF THE INVENTION

[0043] The temperature measurement method, temperature measurement device, and optical heating device of the present invention will be described below with reference to the drawings. Note that the following drawings relating to the temperature measurement device and optical heating device are all schematic illustrations, and the dimensional ratios and numbers in the drawings do not necessarily match the actual dimensional ratios and numbers.

[0044] [First embodiment] First, the configuration of the light heating device 1 will be described. Fig. 1 is a schematic cross-sectional view of the configuration of one embodiment of the light heating device 1 when viewed in the Y direction, and Fig. 2 is a drawing of the light heating device 1 of Fig. 1 when viewed from the +Z side. As shown in Fig. 1, the light heating device 1 of the first embodiment includes a chamber 10, a light source unit 11, and a temperature measuring device 20. The temperature measuring device 20 includes a thermocamera 21, a radiation thermometer 22, and a first calculation unit 23.

[0045] In the first embodiment, the substrate W1 to be processed is assumed to be a silicon wafer, but it may be a semiconductor wafer made of a material other than silicon, a glass substrate, or the like. Each main surface of the substrate W1 to be processed is divided into a first main surface W1a on which a pattern (not shown) is formed, and a second main surface W1b on which no pattern is formed. This is the same even if the substrate W1 to be processed is a semiconductor wafer made of a material other than silicon, or a glass substrate.

[0046] In the following explanation, as shown in FIG. 1, the direction in which the LED substrate 11b and the substrate to be processed W1 face each other is referred to as the Z direction, the direction in which a pair of support members 10a (described later) face each other is referred to as the X direction, and the direction perpendicular to the X direction and the Z direction is referred to as the Y direction.

[0047] Similarly, when expressing a direction, if a distinction is made between positive and negative directions, the direction is written with a positive or negative sign, such as "+Z direction" or "-Z direction," and when a direction is expressed without distinguishing between positive and negative directions, it is simply written as "Z direction."

[0048] As shown in FIG. 1, the chamber 10 includes a pair of support members 10a for supporting the substrate W1 to be processed, a light-transmitting window 10b for allowing light to enter the chamber and for a radiation thermometer 22 to measure the surface temperature of the first main surface W1a of the substrate W1 to be processed, and an observation window 10c for allowing a thermal camera 21 to measure the surface temperature of the second main surface W1b of the substrate W1 to be processed.

[0049] For example, in a configuration in which the light source unit 11, thermo camera 21, and radiation thermometer 22 are housed in the chamber 10, the chamber 10 does not need to be provided with the light-transmitting window 10b or the observation window 10c.

[0050] Furthermore, the support member 10a may support the substrate W1 to be processed in any manner so long as the first main surface W1a is positioned on the XY plane. For example, the support member 10a may have multiple pin-shaped protrusions, and the substrate W1 to be processed may be supported at points by the protrusions.

[0051] 1, the light source unit 11 emits light from LED elements 11a mounted on an LED substrate 11b toward a first main surface W1a of a substrate W1 to be processed, the substrate W1 being supported by a support member 10a. The light source unit 11 may be configured to use an LD, a fluorescent light source, or the like as a light source for heating.

[0052] As shown in FIG. 2, the light source unit 11 is configured so that the LED substrate 11b has a circular shape when viewed from the Z direction in accordance with the shape of the substrate W1 to be processed, but it may also have an elliptical or polygonal shape.

[0053] The peak wavelength of light emitted by the LED element 11a included in the light source unit 11 is preferably within a range of 365 nm to 480 nm. The light source unit 11 of the first embodiment is equipped with an LED element 11a that emits light with a peak wavelength of 395 nm.

[0054] The light-transmitting window 10b transmits at least the light emitted by the LED element 11a and the light in the sensitivity wavelength band of the radiation thermometer 22. The observation window 10c is a so-called light-transmitting window that transmits infrared light observed by the thermal camera 21. Note that the light-transmitting window 10b and the observation window 10c do not need to be light-transmitting to all of the light emitted by the LED element 11a or all of the light in the sensitivity wavelength band of the radiation thermometer 22, as long as the heat treatment of the substrate W1 to be processed and the measurement by the radiation thermometer 22 can be performed without any problems.

[0055] 3 is a view of the substrate W1 being processed, supported by the support member 10a, as viewed from the -Z side. As shown in FIG. 1, the thermal camera 21, which corresponds to the first temperature measuring device, is positioned so as to two-dimensionally measure the temperature of the entire second main surface W1b of the substrate W1 being processed. That is, as shown in FIG. 3, the entire second main surface W1b of the substrate W1 being processed serves as the first measurement region M1. Note that the first measurement region M1 may be a partial region of the second main surface W1b.

[0056] 4 is a view of the substrate W1 to be processed supported by the support member 10a as viewed from the +Z side. The radiation thermometer 22, which corresponds to the second temperature measuring device, has higher temperature measurement accuracy and a narrower measurement range than the thermal camera 21, which is the first temperature measuring device, as shown in FIGS. 1 and 4. The radiation thermometer 22 is disposed on the +Z side of the chamber 10 so that a portion of the region including an alignment mark W1m formed by cutting the first main surface W1a of the substrate W1 to be processed becomes the second measurement region M2. For ease of explanation, only one alignment mark W1m is shown larger than usual in FIG. 4.

[0057] 5 is a graph showing the relationship between infrared wavelength and emissivity of silicon (Si) at various temperatures. As shown in FIG. 5, the emissivity of silicon, including its temperature characteristics, is known and is a given value. The alignment mark W1m in the first embodiment is a mark formed by cutting the surface of the substrate W1 to be processed, and the surface material is silicon. Therefore, the second measurement region M2 including the alignment mark W1m in the first embodiment contains silicon with a known emissivity.

[0058] The radiation thermometer 22 is disposed in a hole 11h provided in the LED substrate 11b so as to be outside the space A1 sandwiched between the LED substrate 11b and the substrate to be processed W1, as indicated by the long dashed line in FIG.

[0059] The sensitivity wavelength band of the thermo camera 21 and radiation thermometer 22 varies slightly depending on the object to be measured and the temperature range, as described above, but is mainly in the near-infrared to far-infrared wavelength band (for example, 0.8 μm to 14 μm).

[0060] The first calculation unit 23 calculates a correction value for correcting the temperature distribution measured by the thermal camera 21 based on the temperature of the second measurement area M2 acquired by the radiation thermometer 22 and the temperature distribution of the first measurement area M1 measured by the thermal camera 21, and outputs the correction value to the thermal camera 21. The specific method will be described in detail below in the explanation of the temperature measurement method.

[0061] Next, a temperature measurement method using the temperature measurement device 20 will be described based on the configuration of the light heating device 1. The substrate to be processed W1 is placed in the chamber 10 so that the second main surface W1b faces the -Z side where the thermal camera 21 is placed (step S1). This step S1 corresponds to process (A).

[0062] After step S1, the thermal camera 21 measures the temperature distribution in the first measurement region M1 on the second main surface W1b (step S2). This step S2 corresponds to the process (B).

[0063] After step S1, the radiation thermometer 22 measures the temperature of the second measurement region M2 on the first main surface W1a (step S3). This step S3 corresponds to the process (C). Note that either step S2 or step S3 may be performed first.

[0064] After steps S2 and S3, the first calculation unit 23 calculates correction values for correcting each value of the temperature distribution based on the temperature distribution measured by the thermal camera 21 and the temperature measured by the radiation thermometer 22 (step S4).

[0065] More specifically, the temperature difference ΔT (= T1 - T2) between the temperature T1 at a position on the first main surface W1a opposite the second measurement area M2 in the temperature distribution measured by the thermal camera 21 and the temperature T2 measured by the radiation thermometer 22 is calculated.

[0066] The positions where the temperatures T1 and T2 are acquired may be shifted in the XY plane, but it is preferable that the shift be 2% or less of the longest width of the substrate W1 to be processed in each of the X and Y directions.

[0067] After step S4, the temperature difference ΔT calculated in step S4 is added to each value of the temperature distribution measured by the thermal camera 21 (step S5). Steps S4 and S5 correspond to process (D).

[0068] After step S5, the thermal camera 21 outputs the corrected temperature distribution data (step S6). The temperature distribution data output by the thermal camera 21 refers to output to, for example, a display unit provided in the thermal camera 21, or to an external device such as a PC or display device. Furthermore, in the first embodiment, the thermal camera 21 is configured to correct the temperature distribution, but the first calculation unit 23 may be configured to receive the temperature distribution data before correction from the thermal camera 21, perform correction processing, and output the data.

[0069] By using the above-described device and method, a wider area can be secured for arranging the light source unit 11 compared to when the temperature of the first main surface W1a of the substrate W1 to be processed is directly measured by the thermal camera 21. Furthermore, according to the above-described method, the temperature distribution of the second main surface W1b measured by the thermal camera 21 is corrected by the measurement value measured by the radiation thermometer 22, which has higher measurement accuracy, so that the temperature distribution of the second main surface W1b can be obtained with higher accuracy.

[0070] Furthermore, according to the above method, the temperature distribution can be corrected by the temperature difference ΔT between the first principal surface W1a and the second principal surface W1b at the same position in the XY plane, so that the temperature distribution of the first principal surface W1a can be essentially obtained while acquiring the temperature distribution of the second principal surface W1b using the first temperature measuring device.

[0071] The above-described temperature measurement method can be used in any step while the temperature of the substrate W1 to be processed is rising or falling, or while the substrate W1 is being maintained at a predetermined temperature.

[0072] The second measurement region M2 may be a region on the first principal surface W1a where no pattern is formed, or a region on the first principal surface W1a that contains a material with a known emissivity and does not contain the alignment mark W1m. Furthermore, when it is not essential to obtain the temperature distribution of the first principal surface W1a, the second measurement region M2 may be a region on the second principal surface W1b.

[0073] Here, it is conceivable that the second measurement region M2 contains a mixture of multiple materials with different emissivities. In such a case, the radiation thermometer 22 is set to, for example, the average emissivity of each material or the emissivity of the material most abundant in the second measurement region M2. Furthermore, when a material whose emissivity is highly temperature-dependent is included, the temperature dependency of the emissivity of the second measurement region M2 may be measured in advance using an electric furnace with a temperature measurement function, and the emissivity may be appropriately set based on the measured value and the temperature during the heating process.

[0074] [Second embodiment] The configuration of the second embodiment of the light heating device 1 of the present invention will be described, focusing on the differences from the first embodiment.

[0075] Fig. 6 is a schematic cross-sectional view of the configuration of one embodiment of the optical heating device 1 when viewed in the Y direction, and Fig. 7 is a drawing of the optical heating device 1 in Fig. 6 when viewed from the +Z side. Also, Fig. 8 is a drawing of the substrate to be processed W1 supported by the support member 10a when viewed from the +Z side. As shown in Figs. 6 to 8, the temperature measuring device 20 of the second embodiment further includes a plurality of radiation thermometers 24 corresponding to the third temperature measuring device, a second calculation unit 25, and a memory unit 26.

[0076] The second calculation unit 25 calculates the emissivity to be set in each radiation thermometer 24 based on the temperature distribution data output from the thermal camera 21 and the emissivity data for each material of the pattern on the first principal surface W1a stored in the storage unit 26. A specific calculation method will be described in detail later in the explanation of the temperature measurement method.

[0077] The memory unit 26 stores emissivity data relating to the material of the pattern located in the third measurement region M3. The data may be known data or may be a value measured in advance before the substrate W1 to be processed is placed in the chamber 10.

[0078] 6, the second calculation unit 25 and the storage unit 26 are shown separately, but the storage unit 26 may be included in the second calculation unit 25. Furthermore, the first calculation unit 23 and the second calculation unit 25 may be configured as a single calculation unit, and the storage unit 26 may be further included in the calculation unit.

[0079] Next, the temperature measurement method will be described in terms of differences from the first embodiment. In the temperature measurement method using the light heating device 1 of the second embodiment, after steps S1 to S5 described above in the description of the first embodiment are performed, in step S6 the thermal camera 21 outputs corrected temperature distribution data to the second calculation unit 25.

[0080] After step S6, the second calculation unit 25 reads out the emissivity data related to the material of the pattern located in each of the third measurement regions M3 shown in FIG. 8, which is stored in the storage unit 26 (step S7).

[0081] After step S7, the second calculation unit 25 calculates the emissivity to be set for each radiation thermometer 24 based on the emissivity data read out from the memory unit 26 and the data of the corrected temperature distribution output from the thermal camera 21 (step S8).

[0082] Specifically, the temperature T3 of the area located on the opposite side of the third measurement area M3 is extracted from the temperature distribution data output from the thermal camera 21. Then, the emissivity at the temperature T3 of the material of each pattern arranged in the third measurement area M3 is calculated from the temperature characteristic data of the emissivity for each material read from the storage unit 26.

[0083] After step S8, the second calculation unit 25 outputs the calculated emissivity to each radiation thermometer 24, and the emissivity is set in each radiation thermometer 24 (step S9). Steps S8 and S9 correspond to the process (E).

[0084] After step S9, the temperature of each third measurement region M3 is measured by each radiation thermometer 24 (step S10).

[0085] With the above configuration and method, the emissivity of the radiation thermometer 24 for measuring the temperature of the first main surface W1a is corrected to a more appropriate value according to the pattern material and the temperature during processing. Therefore, with the above configuration, the temperature at any position on the first main surface W1a of the substrate W1 to be processed can be measured with high accuracy.

[0086] Although there may be only one third measurement region M3, providing multiple third measurement regions M3 allows the first principal surface W1a to be divided into several zones and the temperature of each zone to be monitored, as shown by the dashed dotted lines in Fig. 8. With this configuration, the power supplied to the corresponding LED elements 11a can be individually controlled, allowing for more precise temperature control for each zone.

[0087] [Another embodiment] Another embodiment will be described below.

[0088] <1> Fig. 9 is a schematic cross-sectional view of another embodiment of the optical heating device 1 as viewed from the Y direction. As shown in Fig. 9, the radiation thermometer 22 may be configured to receive infrared light radiated from the substrate W1 to be processed via a fiber 22a, rather than directly receiving the light.

[0089] With the above configuration, the observation hole 11h of the light source unit 11 can be made smaller, allowing for more LED elements 11a to be placed. In other words, it is possible to configure a light heating device 1 that can irradiate the workpiece substrate W1 with light of higher intensity. As shown in Fig. 9, the radiation thermometer 22 is located outside the space A1 sandwiched between the workpiece substrate W1 and the LED substrate 11b.

[0090] Note that, in addition to the fiber 22a, an optical member such as a mirror can be used as long as it can guide the infrared light emitted from the substrate W1 to the radiation thermometer 22. The above configuration can also be applied to the radiation thermometer 24 in the same manner.

[0091] <2> Fig. 10 is a schematic cross-sectional view of another embodiment of the optical heating device 1 as viewed from the Y direction. As shown in Fig. 10, the temperature measurement device 20 may be provided with a radiation thermometer array 27 as the first temperature measurement device, in which a plurality of radiation thermometers are arranged in an array to two-dimensionally measure the temperature of the second main surface W1b of the substrate to be processed W1.

[0092] Furthermore, as shown in FIG. 10, the radiation thermometer 22 may be positioned so that it does not face any of the radiation thermometers constituting the radiation thermometer array 27 in the Z direction, and the first measurement area M1 (not shown) and the second measurement area M2 (not shown) do not overlap when the substrate W1 to be processed is viewed from the Z direction.

[0093] <3> The configurations of the light heating device 1 and the temperature measuring device 20 described above are merely examples, and the present invention is not limited to the configurations shown in the drawings. [Explanation of symbols]

[0094] 1 : Optical heating device 10: Chamber 10a: Support member 10b: Translucent window 10c: Observation window 11: Light source section 11a: LED element 11b: LED board 11h: Hole 20 : Temperature measuring device 21: Thermal camera 22 : Radiation thermometer 22a: Fiber 23: First calculation section 24 : Radiation thermometer 25: Second calculation section 26 : Storage section 27: Radiation thermometer array 100: Optical heating device 101a: LED element 101b: LED board 101h: Hole 102: Thermal Camera A1 : Space M1: First measurement area M2: Second measurement area M3: Third measurement area W1: Substrate to be processed W1a: First principal surface W1b: Second principal surface W1m: Alignment mark

Claims

1. 1. A method for measuring a temperature of a substrate having a pattern formed on a first major surface, comprising: a step (A) of positioning the substrate so that a first temperature measuring device that observes infrared light radiated from the substrate and measures temperature two-dimensionally can receive infrared light radiated from a first measurement region on a second main surface of the substrate opposite to the first main surface; After the step (A), a step (B) of measuring a temperature distribution in the first measurement region on the second main surface by the first temperature measuring device; After the step (A), a step (C) is performed in which a second temperature measuring device, which has higher temperature measurement accuracy and a narrower measurement range than the first temperature measuring device and is arranged to be located inside the substrate when viewed from a direction perpendicular to the first main surface, is used to observe infrared light emitted from the substrate and measure the temperature of a second measurement region on the first main surface of the substrate, the second temperature measuring device including a material with a known emissivity; A temperature measurement method characterized by including, after carrying out steps (B) and (C), a step (D) of correcting each value of the temperature distribution of the first measurement region measured by the first temperature measuring device based on the temperature distribution of the first measurement region measured by the first temperature measuring device and the temperature of the second measurement region measured by the second temperature measuring device.

2. 2. The temperature measuring method according to claim 1, wherein the first measurement area and the second measurement area overlap when the substrate is viewed in a direction perpendicular to the first main surface.

3. 2. The temperature measurement method according to claim 1, wherein the step (C) measures the temperature of the second measurement region including an alignment mark on the first main surface by the second temperature measuring device.

4. 2. The temperature measurement method according to claim 1, wherein the step (C) measures the temperature of the second measurement region on the first main surface where no pattern is formed by the second temperature measuring device.

5. a step (E) of setting an emissivity in a third temperature measuring device that measures the temperature of a third measurement area on the first main surface by observing infrared light emitted from the substrate, the third measurement area being different from the first measurement area and the second measurement area; and (F) measuring the temperature of the third measurement area by the third temperature measuring device after the step (E), 5. The temperature measurement method according to claim 1, wherein in the step (E), the emissivity set in the third temperature measuring device is calculated based on the temperature distribution corrected in the step (D) and a material on the first main surface of the substrate placed in the third measurement area.

6. An apparatus for measuring the temperature of a substrate having a pattern formed on a first main surface, comprising: a first temperature measuring device that observes infrared light emitted from the substrate and two-dimensionally measures the temperature of a first measurement region on a second main surface of the substrate opposite to the first main surface; a second temperature measuring device that has higher temperature measurement accuracy and a narrower measurement range than the first temperature measuring device, and that observes infrared light emitted from the substrate to measure the temperature of a second measurement region on the first main surface of the substrate, the second temperature measuring device being located inside the substrate when viewed from a direction perpendicular to the first main surface; a first calculation unit that corrects each value of the temperature distribution measured by the first temperature measuring device based on the temperature distribution of the first measurement area measured by the first temperature measuring device and the temperature of the second measurement area measured by the second temperature measuring device.

7. a third temperature measuring device that measures the temperature of a third measurement area by observing infrared light emitted from the third measurement area, the third measurement area being different from the first measurement area and the second measurement area; a memory unit in which data on the material on the first main surface of the substrate placed in the third measurement area is stored; 7. The temperature measuring device according to claim 6, further comprising a second calculation unit that calculates the emissivity to be set in the third temperature measuring device based on the temperature distribution of the substrate measured by the first temperature measuring device and the data of the material stored in the memory unit.

8. The temperature measuring device according to claim 6 or 7, a chamber in which the substrate is housed; a support member for supporting the substrate within the chamber; a light source unit that emits light toward a first main surface of the substrate supported in the chamber, An optical heating device, characterized in that the first temperature measuring device and the second temperature measuring device are arranged outside a space sandwiched between the substrate and the light source unit.

9. the chamber has a light-transmitting window formed on a wall surface facing each main surface of the substrate, the light-transmitting window allowing infrared light to pass therethrough; 9. The optical heating device according to claim 8, wherein the temperature measuring device is disposed outside the chamber and measures the temperature of the substrate through the light-transmitting window.

Images