Light heating device

Abstract

To provide an optical heating device capable of performing heating processing under control to prevent a processing substrate from having temperature unevenness without using any thermometer.SOLUTION: An optical heating device comprises: a chamber which houses a processed substrate; a support member which supports the processed substrate in the chamber; a plurality of solid light sources which emit heating lights toward a principal surface of the processed substrate; a plurality of reference light sources which are supplied with electric power having the same electric power value and emit reference lights toward the principal surface of the processed substrate; a plurality of optical detectors which are arranged on a plane parallel with the principal surface of the processed substrate to correspond to the plurality of reference light sources, respectively, and output signals corresponding to intensities of received reference lights; and a control part which executes a reference mode and a heating mode. The corresponding reference light sources and optical detectors are arranged so that light emission surfaces of the reference light sources and light reception surfaces of the optical detector face each other across the processed substrate, and the optical detectors are configured to receive the reference lights emitted from the reference light sources and transmitted through the processed substrate.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a light heating device. [Background technology]

[0002] In the semiconductor manufacturing process, various heat treatments such as film formation, oxidation and diffusion, modification, and annealing are performed on substrates such as semiconductor wafers. These processes often use heat treatment methods that use light irradiation, which allows for non-contact processing.

[0003] Known devices for heat-treating a substrate include devices that are equipped with lamps such as halogen lamps or solid-state light sources such as LEDs and irradiate the substrate with light for heating (hereinafter referred to as "heating light"). For example, Patent Document 1 listed below describes a wafer heating unit equipped with multiple LEDs. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-009927 A Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, there has been active research into further miniaturization of semiconductor manufacturing processes, with processes on the order of a few nm becoming mainstream. However, there are many issues that arise as the semiconductor manufacturing process becomes more miniaturized, and methods and equipment to solve these issues are being researched on a daily basis.

[0006] One of the issues that arise in the miniaturization of semiconductor manufacturing processes is the issue of heat treatment temperature. Conventionally, heat treatment steps such as annealing in semiconductor manufacturing processes have generally been performed at temperatures in the range of 500°C to 1000°C (over 1000°C in some processes).

[0007] However, in semiconductor manufacturing processes on the order of a few nm, if heat treatment is performed in the above temperature range as in conventional processes, the narrow wiring and minute elements formed on the semiconductor wafer cannot withstand the thermal damage and deteriorate to an unacceptable level. For this reason, as semiconductor manufacturing processes become more miniaturized, there is a demand for heat treatment at lower temperatures (500°C or lower) than before.

[0008] In addition, the quality of a film formed on a semiconductor wafer may depend on the temperature during the heat treatment in the semiconductor manufacturing process, so the heat treatment in the semiconductor manufacturing process must be performed so that the entire semiconductor wafer is heated without temperature unevenness.

[0009] The present inventors have been studying an optical heating device capable of heating a substrate such as a semiconductor wafer at a lower temperature than conventional devices without causing temperature unevenness, and have found the following problems. The following will be described with reference to the drawings.

[0010] In the semiconductor manufacturing process, a method of performing heat treatment on a semiconductor wafer without temperature unevenness by using a thermometer to refer to the temperature distribution of the semiconductor wafer is known. A specific method is, for example, a method of acquiring temperature data of the semiconductor wafer during heat treatment using a radiation thermometer capable of non-contact temperature measurement by detecting infrared light emitted from an object, and adjusting the intensity of light irradiated onto the semiconductor wafer according to the temperature data.

[0011] It is known that the wavelength peak of the radiant energy of light emitted from an object shifts to the shorter wavelength side as the temperature rises. For this reason, in general, commercially available radiation thermometers, the lower the detection temperature range, the longer the detection wavelength range of infrared light is set. As a guideline, for example, a radiation thermometer with a detection temperature range of 500°C to 2000°C has a detection wavelength range of infrared light set to 0.7μm to 1.0μm, and a radiation thermometer with a detection temperature range of 100°C to 1000°C has a detection wavelength range of infrared light set to 1.5μm to 4.0μm. When it is expected to be used in a temperature range of 500°C or less, a radiation thermometer with a detection wavelength range of infrared light of 1.5μm to 4.0μm is generally adopted.

[0012] However, it is difficult for a radiation thermometer with this detection wavelength range to accurately refer to the temperature variation of a semiconductor wafer (especially a silicon wafer) during heat treatment. The reason for this will be explained below in the case where the substrate to be treated is a silicon wafer.

[0013] Figure 8 is a graph showing the relationship between the wavelength of infrared light and the emissivity of silicon (Si) at each temperature. Silicon (Si) has distinctive emissivity characteristics, and as shown in Figure 8, the shape of the wavelength-emissivity characteristic curve varies greatly depending on the temperature in the region longer than 1.5 μm compared to the region shorter than 1.5 μm, and the variation in emissivity with respect to temperature variation becomes extremely large.

[0014] For this reason, in a radiation thermometer with a detection wavelength range of 1.5 μm to 4.0 μm, the emissivity of the silicon wafer fluctuates with the temperature rise caused by the heat treatment, and as the temperature rises, the radiation thermometer gradually becomes unable to accurately measure the temperature of the silicon wafer.

[0015] In such a case, a method may be adopted in which an appropriate emissivity is appropriately set in the radiation thermometer in accordance with the temperature rise, but this method is not practical because it requires checking the reference temperature using a separate thermometer (e.g., a thermocouple) that can obtain the temperature of the silicon wafer more accurately than the radiation thermometer.

[0016] In view of the above-mentioned problems, an object of the present invention is to provide a light heating device capable of performing heat treatment while controlling so as to suppress temperature unevenness in a substrate to be treated, without using a thermometer. [Means for solving the problem]

[0017] The light heating device of the present invention is a chamber for accommodating a substrate to be heat-treated; a support member for supporting the substrate to be processed within the chamber; A plurality of solid-state light sources that emit heating light having a main emission wavelength in the range of 300 nm to 1050 nm toward a main surface of the substrate supported by the support member; A plurality of reference light sources are arranged on a plane parallel to the main surface of the substrate to be processed, and are supplied with electric power of the same value to emit reference light having a main emission wavelength in the range of 1.2 μm to 6.0 μm toward the main surface of the substrate to be processed; a plurality of photodetectors arranged on a plane parallel to the main surface of the substrate to be processed so as to correspond to the plurality of reference light sources, respectively, and outputting signals corresponding to the intensities of the received reference light; a control unit that executes a reference mode in which a power value of power to be supplied to each of the plurality of solid-state light sources is determined by comparing intensity values ​​of the plurality of reference light obtained by the signals output from the plurality of photodetectors, and a heating mode in which power of the power value determined in the reference mode is supplied to each of the plurality of solid-state light sources, The corresponding reference light source and the photodetector are arranged so that the light emission surface of the reference light source and the light receiving surface of the photodetector face each other across the substrate to be processed, and the photodetector is configured to receive the reference light emitted from the reference light source and transmitted through the substrate to be processed.

[0018] In addition, the light heating device of the present invention is a chamber for accommodating a substrate to be heat-treated; a support member for supporting the substrate to be processed within the chamber; A plurality of solid-state light sources that emit heating light having a main emission wavelength in the range of 300 nm to 1050 nm toward a main surface of the substrate supported by the support member; A plurality of reference light sources are arranged on a plane parallel to the main surface of the substrate to be processed, and are supplied with electric power of the same value to emit reference light having a main emission wavelength in the range of 1.2 μm to 6.0 μm toward the main surface of the substrate to be processed; a plurality of photodetectors arranged on a plane parallel to the main surface of the substrate to be processed so as to correspond to the plurality of reference light sources, respectively, and outputting signals corresponding to the intensities of the received reference light; a control unit that executes a reference mode in which a power value of power to be supplied to each of the plurality of solid-state light sources is determined by comparing intensity values ​​of the plurality of reference light obtained by the signals output from the plurality of photodetectors, and a heating mode in which power of the power value determined in the reference mode is supplied to each of the plurality of solid-state light sources, the photodetector is configured to receive the reference light emitted from the corresponding reference light source and reflected by a main surface of the substrate to be processed; Each of the plurality of reference light sources and the plurality of photodetectors corresponding to each other includes: a plurality of reference light sources are configured to output the reference light having a same optical path length to a point where the reference light is incident on the substrate to be processed, The optical path length of the principal ray of the reference light reflected by the main surface of the substrate to be processed and incident on the photodetector is configured to be the same.

[0019] In this specification, the term "reference light" refers to light that is emitted from a light source, passes through the substrate to be processed or is reflected by the main surface of the substrate to be processed, and is then received by a photodetector, and is used primarily for referring to temperature variations in the substrate to be processed, rather than for heating the substrate to be processed.

[0020] As used herein, the term "dominant emission wavelength" refers to the peak wavelength in the spectrum at which the light intensity is highest.

[0021] In this specification, "power of the same power value" is not limited to the case where the power values ​​are completely the same, but allows for errors caused by the circuit configuration and errors that may occur in control. Note that "power value" corresponds to a current value or a voltage value depending on the light source, and "supplying power" corresponds to supplying a current and applying a voltage depending on the light source.

[0022] In this specification, "parallel" is not limited to being completely parallel, and a slight inclination equivalent to an error that may occur in constructing the device is permitted.

[0023] In this specification, the term "corresponding light source and photodetector" refers to a light source that emits a reference light and a photodetector that is arranged to mainly receive the reference light.

[0024] The substrate to be processed satisfies the relationship of reflectance + absorptance (emissivity) + transmittance = 1 with respect to the transmittance, reflectance, and absorptance (=emissivity) of the irradiated light. Therefore, the transmittance and reflectance of the substrate to be processed fluctuate with the fluctuation of the emissivity. Also, the emissivity of an object varies slightly depending on the temperature, such as silicon, although it depends on the wavelength range of interest.

[0025] According to this characteristic, the reference light that is incident on the substrate to be processed with the same intensity and passes through the substrate to be processed, or the reference light that is reflected by the main surface of the substrate to be processed, becomes light with an intensity that depends on the temperature of the incident position on the substrate to be processed.

[0026] In other words, if the brightness of each solid-state light source is controlled so that the intensity of the light received by the photodetector is uniform, the temperature distribution over the entire substrate to be processed becomes more uniform, and the substrate to be processed can be heat-processed without temperature unevenness.

[0027] However, if the main emission wavelengths of the heating light and the reference light are very close to each other, the heating light will be transmitted through the substrate to be processed or reflected by the main surface of the substrate to be processed, just like the reference light. In this case, the light detection unit will receive the heating light that has become stray light together with the reference light emitted from the corresponding reference light source, and the intensity of the light received by the light detector will vary not only depending on the temperature of the substrate to be processed, but also on the received heating light. In other words, the control unit will not be able to accurately obtain information on the temperature of the substrate to be processed, and will not be able to properly control the brightness of the solid-state light source.

[0028] For this reason, it is preferable that the main emission wavelengths of the heating light and the reference light are configured to be included in different wavelength ranges. Specifically, it is preferable that the main emission wavelength of the heating light is selected so as to be within a wavelength range in which the absorptance (emissivity) of the substrate to be processed is relatively high, and it is preferable that the main emission wavelength of the reference light is selected so as to be within a wavelength range in which the absorptance (emissivity) of the substrate to be processed is relatively low.

[0029] In particular, when the substrate to be processed is a silicon wafer, the main emission wavelength of the reference light is preferably within the wavelength range of 1.2 μm or more and 6.0 μm or less, in which the temperature dependence of emissivity is significant, and more preferably within the wavelength range of 1.5 μm or more and 4.0 μm or less.

[0030] The main emission wavelength of the heating light emitted by the solid-state light source is in a range different from the above-mentioned wavelength range that includes the main emission wavelength of the reference light, and is preferably in the wavelength range of 300 nm or more and 1050 nm or less, in which silicon has a high absorptivity (emissivity) to light, and more preferably in the wavelength range of 350 nm or more and 1000 nm or less.

[0031] As described above, with the above configuration, the optical heating device can grasp the temperature variation of the entire substrate to be processed without using a thermometer, and can perform heat processing while suppressing the temperature unevenness of the entire substrate to be processed. In addition, since the wavelength bands including the main emission wavelengths of the heating light and the reference light are set to different ranges, the respective lights do not interfere with each other, and the substrate to be processed can be uniformly heated by accurately referring to the temperature variation of the substrate to be processed.

[0032] In addition, the actual temperature of the substrate to be processed can be controlled to be within an acceptable error range by turning on multiple solid-state light sources (heating light sources) at a desired brightness and performing heating processing in a desired lighting pattern, and the temperature to which it is expected to converge (hereinafter referred to as the "approximate temperature") is controlled.

[0033] In the above-mentioned light heating device, The control unit may be configured to turn off the plurality of solid-state light sources when the mode is switched to the reference mode.

[0034] With the above configuration, the amount of heating light received by the photodetector is reduced, and the control unit can refer to the temperature variation of the substrate more accurately, so that the entire substrate is more uniformly heated.

[0035] In the above-mentioned light heating device, Each of the reference light sources may be disposed at a greater distance from the other reference light sources than the distance from the corresponding light detector.

[0036] With the above configuration, it is possible to suppress the amount of reference light emitted from a reference light source other than the corresponding reference light source that is received by the photodetector, and therefore the control unit can refer to the temperature variation of the substrate to be processed with higher accuracy, and the substrate to be processed can be heat-processed while suppressing the temperature unevenness.

[0037] In addition, the light heating device of the present invention is a chamber for accommodating a substrate to be heat-treated; a support member for supporting the substrate to be processed within the chamber; A plurality of heating light sources that emit heating light including infrared light having a wavelength of 1.2 μm or more and 6.0 μm or less toward a main surface of the substrate to be processed supported by the support member; a plurality of photodetectors provided corresponding to any of the plurality of heating light sources, each photodetector outputting a signal corresponding to the intensity of the received infrared light; a control unit that executes a reference mode in which a plurality of intensity values ​​of the heating light obtained by the signals output from the plurality of photodetectors are compared to determine a power value of power to be supplied to each of the plurality of heating light sources, and a heating mode in which power of the power value determined in the reference mode is supplied to each of the plurality of heating light sources, the corresponding heating light source and the corresponding photodetector are arranged such that a light emission surface of the heating light source and a light receiving surface of the photodetector face each other across the substrate to be processed; The photodetector is configured to receive the heating light emitted from the corresponding heating light source and transmitted through the substrate to be processed; The control unit is characterized in that, when switching to the reference mode, supplies electric power of the same power value to at least the heating light sources corresponding to the photodetectors.

[0038] With the above configuration, the optical heating device can utilize the heating light source as a reference light source as well, which reduces the number of components constituting the optical heating device, making it possible to reduce the overall size of the device and reduce manufacturing costs.

[0039] Here, "including infrared light" means including at least infrared light that is transmitted through the substrate to be processed and has a light intensity that can be detected by a photodetector.

[0040] In the above-mentioned light heating device, The control unit may be configured to supply electric power of the same power value to the plurality of heating light sources when the control unit is switched to the reference mode.

[0041] In the above-mentioned light heating device, The control unit may be configured, when switching to the reference mode, to supply power of the same power value to the heating light source corresponding to the photodetector, and to stop supplying power to the other heating light sources.

[0042] With the above configuration, in the reference mode, each photodetector receives light emitted from a heating light source to which the same power value is supplied. Therefore, errors due to differences in brightness of each heating light source contained in the signals output from the multiple photodetectors are suppressed. Therefore, the control unit can more accurately refer to the temperature variation of the substrate to be processed, and the entire substrate to be processed can be more uniformly heated.

[0043] In addition, in the reference mode, the control unit stops supplying power to a heating light source that is not compatible with the photodetector, thereby preventing the photodetector from receiving light emitted from the incompatible heating light source. This allows the control unit to more accurately refer to temperature variations in the substrate to be processed, and the entire substrate to be processed can be more uniformly heated.

[0044] In the above-mentioned light heating device, The heating light source may be a solid-state light source.

[0045] With the above configuration, the control unit can quickly control the on / off of the heating light source and adjust the brightness more precisely. Therefore, the optical heating device does not significantly reduce the temperature of the substrate to be processed while switching the light on and off, and more precise temperature control is possible. Effect of the Invention

[0046] According to the present invention, an optical heating device is realized that can perform heat treatment while controlling so as to suppress temperature unevenness in a substrate to be treated, without using a thermometer. [Brief description of the drawings]

[0047] [Figure 1] 2 is a schematic cross-sectional view of an embodiment of a light heating device when viewed in the Y direction. FIG. [Diagram 2] 2 is a diagram of the chamber of FIG. 1 as viewed from the +Z side. [Diagram 3] FIG. 2 is a block diagram of a control unit according to an embodiment. [Figure 4] 6 is a timing chart showing the relationship between each mode executed by the control unit and the current supplied to the solid-state light source. [Diagram 5] 2 is a schematic cross-sectional view of an embodiment of a light heating device when viewed in the Y direction. FIG. [Figure 6] 2 is a schematic cross-sectional view of an embodiment of a light heating device when viewed in the Y direction. FIG. [Figure 7] 7 is a diagram showing the light source unit in FIG. 6 as viewed from the -Z side. [Figure 8] 1 is a graph showing the relationship between the wavelength of infrared light and the emissivity of silicon (Si) at each temperature. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0048] The light heating device of the present invention will be described below with reference to the drawings. Note that the following drawings related to the light 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.

[0049] [First embodiment] Fig. 1 is a schematic cross-sectional view of a first embodiment of a light heating device 1 when viewed in the Y direction, and Fig. 2 is a drawing of a chamber 2 in Fig. 1 when viewed from the +Z side. As shown in Fig. 1, the light heating device 1 includes a chamber 2, a light source unit 10, a plurality of light detectors 11, and a control unit 12. In Fig. 2, a light-transmitting window 2a, which will be described later, is not hatched so that the structure inside the chamber 2 can be visually confirmed.

[0050] In the following description, as shown in FIG. 2, a plane parallel to the main surface W1a of the substrate W1 to be heated and accommodated in the chamber 2 is defined as the XY plane, and as shown in FIG. 1, a direction perpendicular to the XY plane is defined as the Z direction.

[0051] In addition, when expressing a direction, if a distinction is made between positive and negative directions, a positive or negative sign is added, such as "+Z direction" and "-Z direction." When expressing a direction without distinguishing between positive and negative directions, it is simply written as "Z direction."

[0052] In addition, in the explanation of the first embodiment, it is assumed that the substrate W1 to be processed is a silicon wafer, but it is also envisioned that the optical heating device 1 of the present invention can be used for heating a substrate W1 to be processed other than a silicon wafer (e.g., a glass substrate, etc.).

[0053] As shown in FIG. 1, the chamber 2 includes a support member 3 for placing a substrate W1 to be processed inside, a light-transmitting window 2a for guiding light emitted from the light source unit 10 to the inside, and a light-transmitting window 2b for guiding light (reference light R1 described later) emitted from the light source unit 10 and transmitted through the substrate W1 to the outside of the chamber 2.

[0054] As shown in Figures 1 and 2, the support member 3 has a configuration in which a plurality of protrusions 3b are provided on a base 3a, and the substrate W1 to be processed is placed and supported on the tips of the plurality of protrusions 3b. As shown in Figure 2, the base 3a of the support member 3 has a circular ring shape, and is configured so that light (reference light R1 described below) that has passed through the substrate W1 to be processed is not blocked before reaching the light-transmitting window 2b, as shown in Figure 1. Note that the configuration of the support member 3 shown in Figures 1 and 2 is merely an example, and the support member 3 may have a different shape or structure.

[0055] As shown in FIG. 1, the light source unit 10 includes a plurality of solid-state light sources 10a that emit heating light H1, a plurality of reference light sources 10b that emit reference light R1, and a light source substrate 10c on which the plurality of solid-state light sources 10a and the plurality of reference light sources 10b are mounted.

[0056] The light source substrate 10c is arranged so that the mounting surface 10p on which the solid-state light source 10a and the reference light source 10b are mounted is parallel to the XY plane. That is, in the first embodiment, the solid-state light source 10a and the reference light source 10b are arranged on the same plane parallel to the XY plane and are arranged so as to emit light toward the main surface W1a of the substrate W1 to be processed.

[0057] The solid-state light source 10a in the first embodiment is an LED having a main emission wavelength of 400 nm. The solid-state light source 10a may be an LED that emits light having a main emission wavelength other than 400 nm, or a solid-state light source other than an LED may be used.

[0058] In order to efficiently heat-treat the silicon wafer, which is the substrate W1 to be processed in this embodiment, the main emission wavelength of the solid-state light source 10a is preferably within the wavelength range of 300 nm or more and 1050 nm or less, in which the absorption rate is high, as shown in FIG. 8, and more preferably within the wavelength range of 350 nm or more and 1000 nm or less.

[0059] The reference light source 10b in the first embodiment is an LED with a main emission wavelength of 1.5 μm. The reference light source 10b may be an LED that emits light with a main emission wavelength different from 1.5 μm, or a solid-state light source other than an LED, such as an LD, may be used.

[0060] The main emission wavelength of the reference light source 10b is set to a wavelength range different from the range in which the main emission wavelength of the solid-state light source 10a described above is set. In particular, when the substrate W1 to be processed is a silicon wafer, as shown in Fig. 8, the wavelength range is preferably 1.2 μm to 6.0 μm, in which the variation in emissivity (=1-transmittance-reflectance) is large depending on the temperature variation, and more preferably 1.5 μm to 4.0 μm.

[0061] As shown in FIG. 1, a plurality of photodetectors 11 in the first embodiment are arranged so as to receive the reference light R1 that has passed through the substrate W1 to be processed and has been emitted to the outside of the chamber 2 through the light-transmitting window 2b.

[0062] The photodetector 11 is a component that outputs a signal s1 corresponding to the light intensity of the received reference light R1. The photodetector 11 in the first embodiment is a photodiode, but other than the photodiode, for example, a photovoltaic element, a linear image sensor, etc. may be used.

[0063] Each photodetector 11 corresponds to one of the multiple reference light sources 10b, and is arranged on the XY plane with respect to the corresponding reference light source 10b such that the light receiving surface 11a faces the light emission surface 10q of the reference light source 10b in the Z direction.

[0064] 1, the separation distance d1 between the corresponding reference light source 10b and the photodetector 11 is configured to be 80 mm, and the separation distance d2 between adjacent photodetectors 11 is configured to be 100 mm. In other words, the separation distance d2 between adjacent photodetectors 11 is configured to be larger than the separation distance d1 between the corresponding reference light source 10b and the photodetector 11. Note that, if the reference light source 10b is a light source that emits reference light R1 with a sufficiently small divergence angle, such as an LD, the respective separation distances (d1, d2) may be set arbitrarily regardless of the above.

[0065] Fig. 3 is a block diagram of the control unit 12 in the first embodiment. As shown in Fig. 3, the control unit 12 includes an input circuit 12a, a temperature distribution control circuit 12b, a lighting control circuit 12c, and an output circuit 12d.

[0066] The control unit 12 is configured to execute a reference mode in which the intensity values ​​of the multiple reference light beams R1 obtained by the signals s1 output from the multiple photodetectors 11 are compared to determine the current value of the current s2 to be supplied to each of the multiple solid-state light sources 10a, and a heating mode in which the current s2 having the current value determined in the reference mode is supplied to each of the multiple solid-state light sources 10a. The control unit 12 is, for example, a calculation device such as an MPU or MCU, or an external device for calculation such as a PC or tablet.

[0067] 4 is a timing chart showing the relationship between each mode executed by the control unit 12 and the current s2 supplied to some of the solid-state light sources 10a, where (a) shows the timing of switching between the modes, (b) shows the output of a trigger signal s6 output by the lighting control circuit 12c described later, and (c) shows an example of the fluctuation of the current s2 supplied to the solid-state light sources 10a by the control unit 12. Below, the operation of each block will be described with reference to FIG. 3, and then an example of the operation of each mode of the control unit 12 will be described with reference to FIGS. 3 and 4.

[0068] When signals s1 output from the multiple photodetectors 11 are input to the input circuit 12a, the input circuit 12a generates light intensity data s3 that can be processed by the temperature distribution control circuit 12b based on the signals s1, and outputs the generated light intensity data s3 to the temperature distribution control circuit 12b.

[0069] In addition, when the input circuit 12a has output all of the light intensity data s3 to be compared to the temperature distribution control circuit 12b, it outputs a notification signal s4 to the lighting control circuit 12c to notify the temperature distribution control circuit 12b that the output of the light intensity data s3 has been completed.

[0070] When light intensity data s3 to be compared is input from the input circuit 12a, the temperature distribution control circuit 12b calculates the current value of the current s2 to be supplied to the multiple solid-state light sources 10a shown in Fig. 1 based on the light intensity data s3. When the calculation of the current value of the current s2 is completed, the temperature distribution control circuit 12b outputs current value data s5 to the output circuit 12d.

[0071] The current value of the current s2 supplied to the solid-state light source 10a may be calculated individually for each solid-state light source 10a, or the mounting surface 10p on which the solid-state light sources 10a of the light source substrate 10c are mounted may be divided into several regions, and the current value of the current s2 may be calculated and determined for each solid-state light source 10a included in each region.

[0072] When the notification signal s4 output by the input circuit 12a is input, the lighting control circuit 12c outputs a trigger signal s6 to the output circuit 12d after a predetermined time has elapsed, for causing the output circuit 12d to start outputting the current s2. Note that the lighting control circuit 12c of the first embodiment includes a timer (not shown) that counts the time for switching between the heating mode and the reference mode.

[0073] When the current value data s5 is input from the temperature distribution control circuit 12b, the output circuit 12d enters a state in which it supplies a current s2 at a predetermined current value to each solid-state light source 10a and waits for a trigger signal s6 to be input from the lighting control circuit 12c. Then, when the trigger signal s6 is input from the lighting control circuit 12c, the output circuit 12d starts supplying the current s2 to each solid-state light source 10a at the set current value.

[0074] The heating mode X1 is started by outputting a trigger signal s6 from the lighting control circuit 12c to the output circuit 12d at time t1 as shown in Fig. 4. When the heating mode X1 is started, the output circuit 12d supplies a current s2 with a predetermined current value c1 to each solid-state light source 10a.

[0075] The reference mode X2 is started when a trigger signal s6 for stopping the supply of the current s2 to the solid-state light source 10a is output from the lighting control circuit 12c to the output circuit 12d at time t2 when a predetermined time T1 has elapsed since the time t1 when the heating mode X1 was started. In the first embodiment, as shown in FIG. 4(b), the trigger signal s6 for starting the supply of the current s2 and for stopping the supply of the current s2 are the same signal, and the output circuit 12d is configured to switch its operation every time the trigger signal s6 is input.

[0076] When the reference mode X2 starts, the output circuit 12d stops supplying the current s2 to the solid-state light source 10a, and the light source unit 10 is in a state where the solid-state light source 10a is turned off and only the reference light source 10b is turned on. Then, the multiple photodetectors 11 output to the input circuit 12a a signal s1 based on the reference light R1 received in a state where only the reference light source 10b is turned on.

[0077] As shown in Fig. 3, when multiple signals s1 are input to the input circuit 12a, each block executes the above-mentioned respective operations in order. Then, the current value c2 of the current s2 output by the output circuit 12d is calculated, and when the current output setting of the output circuit 12d is completed, the output circuit 12d waits for the trigger signal s6 to be output from the lighting control circuit 12c. Then, when the time T2 has elapsed from the time t2, the trigger signal s6 is output from the lighting control circuit 12c to the output circuit 12d, as shown in Fig. 4, and the heating mode X1 is started.

[0078] Each time (T1, T2) is adjusted appropriately depending on the heating speed, etc., but in the first embodiment, as an example, the time T1 of the heating mode X1 is set to 1 second, and the time T2 of the reference mode X2 is set to 0.1 seconds.

[0079] As described above, the control unit 12 repeats the heating mode X1 and the reference mode X2 to adjust the current value of the current s2 supplied to the multiple solid-state light sources 10a, thereby performing heat treatment while suppressing temperature unevenness of the substrate W1 to be treated.

[0080] With the above configuration, it is possible to refer to the temperature variation of the entire substrate W1 to be processed without using a thermometer, and the heat treatment can be performed while suppressing the temperature unevenness of the entire substrate W1 to be processed. In addition, since the wavelength band including the main emission wavelength of the heating light H1 and the wavelength band including the main emission wavelength of the reference light R1 are set in different ranges, the respective lights do not become stray light and interfere with each other, and the heat treatment and the reference of the temperature variation can be performed with high accuracy.

[0081] The light source unit 10 of the first embodiment is configured by mounting a plurality of solid-state light sources 10a and a plurality of reference light sources 10b on one light source substrate 10c, but may be configured by combining a plurality of light source substrates (10c, 10c, ...) on which a plurality of solid-state light sources 10a and a plurality of reference light sources 10b are mounted. Furthermore, the light source unit 10 may be configured by including a light source substrate 10c on which the solid-state light sources 10a are mounted and a different light source substrate 10c on which the reference light sources 10b are mounted.

[0082] The control unit 12 in the first embodiment is configured to stop the supply of current s2 to the solid-state light source 10a in the reference mode X2. However, if the spectra of the heating light H1 and the reference light R1 are configured to be sufficiently separated and there is no problem in referring to the temperature variation even if the solid-state light source 10a is turned on, the control unit 12 may be configured not to stop the supply of current s2 to the solid-state light source 10a in the reference mode X2.

[0083] In addition, in the first embodiment, the reference light source 10b is turned on in both the heating mode X1 and the reference mode X2, but the control unit 12 may be configured to include a control circuit that switches the reference light source 10b on and off, and to turn on the reference light source 10b only in the reference mode.

[0084] [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.

[0085] Fig. 5 is a schematic cross-sectional view of the second embodiment of the light heating device 1 when viewed in the Y direction. As shown in Fig. 5, in the light heating device 1 of the second embodiment, only solid-state light sources 10a are placed on the light source substrate 10c of the light source section 10. Then, a plurality of reference units 20 each including a corresponding reference light source 10b and a light detector 11 are provided on the +Z side of the light source section 10.

[0086] In the reference unit 20, the reference light source 10b emits reference light R1 (not shown) toward the substrate W1 through a through hole 10h provided in the light source section 10. The photodetector 11 provided in the reference unit 20 receives the light reflected by the main surface W1a of the substrate W1 and returned to the reference unit 20 side through the through hole 10h of the light source section 10.

[0087] 5, each reference unit 20 is configured so that the optical path length d3 of the principal ray Rx of the reference light R1 from the reference light source 10b until it is incident on the substrate W1 to be processed is the same. Also, each reference unit 20 is configured so that the optical path length d4 of the principal ray Rx of the reference light R1 from the principal surface W1a of the substrate W1 to be incident on the photodetector 11 is the same.

[0088] With the above configuration, the light source unit 10 and the photodetector 11 can be arranged together on one side (here, the +Z side) in the Z direction relative to the chamber 2, thereby making it possible to reduce the size of the entire optical heating device 1. Furthermore, in the optical heating device 1 of the second embodiment, one reference unit 20 is configured by the reference light source 10b and the corresponding photodetector 11, making it easy to align the corresponding reference light source 10b and the photodetector 11.

[0089] In addition, the light heating device 1 of the second embodiment is composed of a light source section 10 and a reference unit 20, but the light source section 10 and the reference unit 20 may be integrally configured, or, as in the first embodiment, the light source section 10 may be equipped with a solid-state light source 10a and a reference light source 10b, and only the light detector 11 may be configured as a separate entity.

[0090] [Third embodiment] The configuration of the third embodiment of the light heating device 1 of the present invention will be described, focusing on the differences from the first and second embodiments.

[0091] Fig. 6 is a schematic cross-sectional view of a third embodiment of the optical heating device 1 when viewed in the Y direction, and Fig. 7 is a drawing of the light source unit 10 of Fig. 6 when viewed from the -Z side. As shown in Fig. 7, in the optical heating device 1 of the third embodiment, the light source unit 10 is composed of a plurality of lamp light sources 10d that emit heating light H1 arranged on the XY plane.

[0092] The lamp light source 10d is a light source that emits heating light H1 including infrared light having a wavelength of 1.2 μm or more and 6.0 μm or less, and is, for example, a xenon lamp, etc. Also, as long as the light source can emit infrared light in the above wavelength range, it may be a light source other than a lamp light source, and may be, for example, a solid-state light source such as an LED or LD having a main emission wavelength within the wavelength range.

[0093] The heating light H1 emitted from the lamp light source 10d in the third embodiment contains infrared light in the above wavelength range, and therefore can be used as the reference light R1 in the first embodiment. In other words, the lamp light source 10d functions not only as a heating light source but also as a reference light source.

[0094] In the third embodiment, when the control unit 12 switches to the reference mode, it controls so that the current s2 (or voltage) supplied (applied) to the multiple lamp light sources 10d corresponding to the photodetector 11 is the same, and stops the supply (application) of the current s2 (or voltage) to the multiple lamp light sources 10d that do not correspond to the photodetector 11.

[0095] In addition, the control unit 12 may be configured to control so as to supply (apply) the same current s2 (or voltage) to all the lamp light sources 10d in the reference mode.

[0096] With the above configuration, there is no need to mount a heating light source and a reference light source separately, and the light heating device 1 can be configured with a simpler configuration, which makes it easier to perform maintenance work on the device and to check the cause of any malfunctions. [Explanation of symbols]

[0097] 1 : Optical heating device 2: Chamber 2a: Translucent window 2b: Translucent window 3: Support member 3a: Pedestal 3b: Protrusion 10: Light source section 10a: solid state light source 10b: Reference light source 10c: Light source board 10d: Lamp light source 10h: Through hole 10p: Placement surface 10q: Light exit surface 11: Photodetector 11a: Light receiving surface 12: Control section 12a: Input circuit 12b: Temperature distribution control circuit 12c: Lighting control circuit 12d: Output circuit 20 : Reference unit H1: Heating light R1: Reference beam Rx: chief ray W1: Substrate to be processed W1a: Main surface

Claims

1. a chamber for accommodating a substrate to be heat-treated; a support member for supporting the substrate to be processed within the chamber; A plurality of solid-state light sources that emit heating light having a main emission wavelength in the range of 300 nm to 1050 nm toward a main surface of the substrate supported by the support member; a plurality of reference light sources arranged on a plane parallel to the main surface of the substrate to be processed, each of which is supplied with the same power value and emits reference light having a main emission wavelength in the range of 1.2 μm to 6.0 μm toward the main surface of the substrate to be processed; a plurality of photodetectors arranged on a plane parallel to the main surface of the substrate to be processed so as to correspond to the plurality of reference light sources, respectively, and outputting signals corresponding to the intensities of the received reference light; a control unit that executes a reference mode in which a power value of power to be supplied to each of the plurality of solid-state light sources is determined by comparing intensity values ​​of the plurality of reference light obtained by the signals output from the plurality of photodetectors, and a heating mode in which power of the power value determined in the reference mode is supplied to each of the plurality of solid-state light sources, An optical heating device characterized in that the corresponding reference light source and the optical detector are arranged so that the light emission surface of the reference light source and the light receiving surface of the optical detector face each other across the substrate to be processed, and the optical detector is configured to receive the reference light emitted from the reference light source and transmitted through the substrate to be processed.

2. a chamber for accommodating a substrate to be heat-treated; a support member for supporting the substrate to be processed within the chamber; A plurality of solid-state light sources that emit heating light having a main emission wavelength in the range of 300 nm to 1050 nm toward a main surface of the substrate supported by the support member; a plurality of reference light sources arranged on a plane parallel to the main surface of the substrate to be processed, each of which is supplied with the same power value and emits reference light having a main emission wavelength in the range of 1.2 μm to 6.0 μm toward the main surface of the substrate to be processed; a plurality of photodetectors arranged on a plane parallel to the main surface of the substrate to be processed so as to correspond to the plurality of reference light sources, respectively, and outputting signals corresponding to the intensities of the received reference light; a control unit that executes a reference mode in which a power value of power to be supplied to each of the plurality of solid-state light sources is determined by comparing intensity values ​​of the plurality of reference light obtained by the signals output from the plurality of photodetectors, and a heating mode in which power of the power value determined in the reference mode is supplied to each of the plurality of solid-state light sources, the photodetector is configured to receive the reference light emitted from the corresponding reference light source and reflected by a main surface of the substrate to be processed; Each of the plurality of reference light sources and the plurality of photodetectors corresponding to each other includes: a plurality of reference light sources are configured to output the reference light having a same optical path length to a point where the reference light is incident on the substrate to be processed, An optical heating device characterized in that the optical path length of a principal ray of the reference light reflected from a main surface of the substrate to be processed and incident on the optical detector is constant.

3. 3 . The light heating device according to claim 1 , wherein the control unit turns off the plurality of solid-state light sources when the mode is switched to the reference mode.

4. 3. The optical heating device according to claim 1, wherein each of the reference light sources is disposed at a greater distance from the other reference light sources than the distance from the corresponding optical detector.

5. a chamber for accommodating a substrate to be heat-treated; a support member for supporting the substrate to be processed within the chamber; A plurality of heating light sources that emit heating light including infrared light having a wavelength of 1.2 μm or more and 6.0 μm or less toward a main surface of the substrate to be processed supported by the support member; a plurality of photodetectors provided corresponding to any of the plurality of heating light sources, each photodetector outputting a signal corresponding to the intensity of the received infrared light; a control unit that executes a reference mode in which a plurality of intensity values ​​of the heating light obtained by the signals output from the plurality of photodetectors are compared to determine a power value of power to be supplied to each of the plurality of heating light sources, and a heating mode in which power of the power value determined in the reference mode is supplied to each of the plurality of heating light sources, the corresponding heating light source and the corresponding photodetector are arranged such that a light emission surface of the heating light source and a light receiving surface of the photodetector face each other across the substrate to be processed; The photodetector is configured to receive the heating light emitted from the corresponding heating light source and transmitted through the substrate to be processed; The optical heating device according to claim 1, wherein when the control unit is switched to the reference mode, the control unit supplies electric power of the same power value to at least the heating light sources corresponding to the optical detectors.

6. The light heating device according to claim 5 , wherein the control unit, when switching to the reference mode, supplies electric power of the same power value to the plurality of heating light sources.

7. The optical heating device according to claim 5, characterized in that, when the control unit switches to the reference mode, it supplies the same power value to the heating light source corresponding to the photodetector and stops supplying power to the other heating light sources.

8. 8. The optical heating device according to claim 5, wherein the heating light source is a solid-state light source.

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