JP6267162B2 - Heat treatment method and heat treatment apparatus - Google Patents

Description

  The present invention relates to a heat treatment method and a heat treatment apparatus using a light source as a heat source.

  For example, in the manufacturing process of a semiconductor device, for example, a film forming process for forming a film on a semiconductor wafer (hereinafter referred to as “wafer”) as a substrate and various processes such as a heat treatment are sequentially performed. In the heat treatment after ion implantation, a higher temperature rise / lower is required to minimize diffusion, but in recent years, with the miniaturization and higher integration of semiconductor devices, the requirement is particularly remarkable.

  Therefore, in recent years, LED light is sometimes used as a heat source of a heat treatment apparatus that performs temperature increase and decrease at a higher speed, as disclosed in Patent Document 1, for example. When using LED light as a heat source, the LEDs are arranged at a high density in order to cope with a high temperature increase.

JP 2010-153734 A

  However, according to the present inventors, in heat treatment using LED light, for example, a wafer with a film not formed on the surface and a wafer with a predetermined film formed on the surface are irradiated with LED light under the same conditions. In this case, it was confirmed that there was a difference in the ultimate temperature between the two wafers.

  When the ultimate temperature is different from the desired temperature, the processing result of the wafer is affected, which is a problem. Therefore, there is a demand for a heat treatment apparatus that can obtain a desired temperature without depending on the surface state of the object to be processed.

  This invention is made | formed in view of this point, and it aims at heating to desired temperature irrespective of the surface state of a to-be-processed object in the heat processing apparatus which uses a light source as a heat source.

In order to achieve the above object, the present invention is a heat treatment method for heat-treating an object to be processed using a plurality of light-emitting elements as a heat source, irradiating the object to be processed with a first illuminance from the light-emitting elements, The reflectance of the object to be processed is obtained, and the correlation between the reflectance of the object to be processed and the reflectance of the temperature increase curve of the object to be processed and the reflectance of the object to be processed at the first illuminance obtained in advance. Based on the above, the illuminance of the light from the light emitting element is corrected from the first illuminance to the second illuminance, and the reflectance of the object to be processed is irradiated with light from the light emitting element at the first illuminance. Is obtained by measuring the illuminance of light reflected by the object to be processed, and the measurement of the illuminance of light reflected by the object to be processed is performed between the object to be processed and the light emitting element. It is characterized by being performed in space .

  According to the present invention, the reflectance of the object to be processed is obtained, and the illuminance of light from the light emitting element is corrected from the first illuminance to the second illuminance based on the reflectance. Regardless, it can be heated to the desired temperature.

  The light emitting element may be disposed at a position facing the back surface of the object to be processed, and light irradiation from the light emitting element may be performed on the back surface of the object to be processed.

Another aspect of the present invention is a heat treatment apparatus for irradiating a target object with light to perform heat treatment, the support member supporting the target object, and the target object supported by the support member. A plurality of light emitting elements provided to irradiate the object to be processed and configured to control the plurality of light emitting elements to irradiate the object to be processed with a first illuminance; And a reflected light monitor that measures the illuminance of light from the light emitting element reflected by the object to be processed, and the control unit is determined in advance and the reflectance of the object to be processed. Based on the relationship between the temperature rise curve of the object to be processed and the reflectance of the object to be processed at the first illuminance, the illuminance of light from the light emitting element is changed from the first illuminance to the second illuminance. corrected, wherein the control unit, light is irradiated to the first illumination from the light emitting element Sometimes, the reflectance of the object to be processed is obtained based on the illuminance of the light measured by the reflected light monitor, and the reflected light monitor has the object to be measured in the space between the object to be processed and the light emitting element. It arrange | positions so that the illumination intensity of the light from the said light emitting element reflected by the process body may be measured .

  The light emitting element may be disposed at a position facing the back surface of the object to be processed.

  According to the present invention, a heat treatment apparatus using a light source as a heat source can be heated to a desired temperature regardless of the surface state of the object to be processed.

It is a longitudinal cross-sectional view which shows the outline of a structure of the heat processing apparatus concerning this Embodiment. It is a top view which shows the outline of a structure of a light emitting element unit. It is a top view which shows the outline of a structure of a heat source. It is explanatory drawing which shows the outline of a structure of a control part. It is a flowchart which shows the outline of the correction method of the illumination intensity in a control part. It is a temperature rising curve of wafers having different surface states. It is a longitudinal cross-sectional view which shows the outline of a structure of the heat processing apparatus concerning other embodiment. It is a top view which shows arrangement | positioning of a reflected light monitor. It is a temperature rise curve when the temperature of wafers having different surface states is raised by the heat treatment apparatus of the present embodiment.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a schematic configuration of a heat treatment apparatus 1 according to an embodiment of the present invention.

  The heat treatment apparatus 1 includes a substantially cylindrical processing container 11 provided with a mounting table 10 on which a wafer W, which is a silicon substrate as an object to be processed, is mounted. The processing container 11 includes a heat treatment unit 12 above the mounting table 10 and a gas diffusion unit 13 provided outside the mounting table 10. Note that a SOC (Spin On Glass) film (not shown) is formed in advance on the wafer W, and in this embodiment, an example is given in which heat treatment is performed to improve the plasma resistance of the SOC film. I will explain.

  A plurality of support pins 20 as support members for supporting the wafer W are provided on the upper surface of the mounting table 10. A temperature sensor 20 a is built in the support pin 20. Therefore, the temperature of the wafer W can be measured in a simulated manner by measuring the temperature of the support pins 20 on which the wafer W is placed by the temperature sensor 20a. For example, a thermocouple is used as the temperature sensor. Note that the temperature sensor 20 a itself such as a thermocouple may be used as the support pin 20. In addition, the temperature of the wafer W is measured in a simulated manner not only by measuring the temperature of the support pins 20 in contact with the wafer W by the temperature sensor 20a but also by supporting the wafer W by the temperature sensor 20a. The case where it measures by making the sensor 20a contact is included.

  A heat source 21 is provided on the lower surface of the top plate 11 a of the processing container 11. The heat source 21 includes a plurality of light emitting element units 30. Each light emitting element unit 30 faces the mounting table 10, in other words, faces the wafer W supported by the support pins 20 so as to irradiate the wafer W mounted on the mounting table 10 with light. Is provided. Each light emitting element unit 30 is supported by the support plate 31a via the electrode 31, and the support plate 31a is supported by the top plate 11a. A refrigerant pipe (not shown) is provided inside the top plate 11a, and each light emitting element unit 30 is cooled by passing cooling water through the refrigerant pipe.

  The light emitting element unit 30 has a support plate 32 formed in a hexagonal shape as shown in FIG. 2, and a large number of light emitting elements 33 are arranged on the surface of the support plate 32. For example, a light emitting diode (LED) is used as the light emitting element 33. A reflective layer 34 is formed between the light emitting elements 33, and the light from the light emitting elements 33 can be reflected to effectively extract the light toward the mounting table 10. The light emitting element 33 and the reflective layer 34 are supported by a support plate 32. In addition, the reflectance of the reflective layer 34 is 0.8 or more, for example.

  Each light emitting element 33 is covered with a lens layer (not shown) formed in a hemispherical shape. The lens layer has an intermediate refractive index between an LED having a high refractive index and air having a refractive index of 1, and is provided to alleviate total reflection caused when light is directly emitted from the LED into the air. By providing the lens layer, light can also be extracted from the side surface of each light emitting element 33. In addition, the light extracted from the side surface is reflected by the reflective layer 34 and irradiated toward the mounting table 10. For example, as shown in FIG. 3, the heat source 21 is configured so that the sides of the hexagonal support plate 32 of one light emitting element unit 30 are adjacent to each other. With such an arrangement configuration, all the light emitting element units 30 are arranged without a gap. A reflected light monitor 51 to be described later is disposed through the light emitting element unit 30 at a predetermined position between the light emitting element units 30, in the present embodiment, at the center of the light emitting element unit 30.

  One light emitting element unit 30 has about 1000 to 2000 light emitting elements 33 mounted thereon. As the LED used as the light emitting element 33, a compound semiconductor such as GaN (gallium nitride) or GaAs (gallium arsenide) having a light wavelength in the range of ultraviolet to near infrared, preferably 360 to 1000 nm is used. . When the heating target is a silicon wafer, it is preferable to use an LED made of a GaAs-based material having a wavelength around 950 to 970 nm, which has a high absorption rate by the silicon wafer.

  A plurality of power supplies 40 that supply current to each light emitting element unit 30 are arranged on the top surface of the top plate 11a. The power source 40 is connected to a control unit 150 described later, and the current instruction value supplied to each light emitting element unit 30 is individually controlled by the control unit 150.

  A processing gas supply pipe 41 for introducing a predetermined processing gas from a processing gas supply mechanism (not shown) is connected to the top plate 11 a of the processing container 11. An exhaust pipe 42 connected to an exhaust device (not shown) is connected to the bottom of the gas diffusion portion 13 of the processing container 11, and the inside of the processing container 11 can be exhausted through the exhaust pipe 42.

  A light transmitting member 43 that transmits light emitted from the light emitting element unit 30 toward the wafer W is separated from the upper surface of the mounting table 10 by a predetermined distance between the mounting table 10 and the light emitting element unit 30. Has been placed. The light transmitting member 43 is supported by, for example, screwing on the lower end of the hanging portion 11b extending vertically downward from the lower surface of the top plate 11a. The hanging portion 11b is formed in an annular shape, and the light emitting element unit 30 is housed in a space surrounded by the hanging portion 11b and the light transmitting member 43 supported by the lower end of the hanging portion 11b. ing. As the light transmitting member 43, for example, quartz or the like is used.

  A plurality of illuminance monitors 50 for measuring the illuminance of light emitted from the light emitting element unit 30 toward the wafer W are arranged on the upper surface of the light transmitting member 43, in other words, on the light emitting element unit 30 side of the light transmitting member 43. Yes. As the illuminance monitor 50, for example, a light receiving element such as a photodiode is used. As described above, the shadow of the illuminance monitor 50 can be prevented from being transferred to the wafer W by arranging the illuminance monitor 50 on the light transmitting member 43 provided away from the upper surface of the mounting table 10. The illuminance monitor 50 is connected to a control unit 150 described later, and light detected by the illuminance monitor 50 is converted into an electrical signal by the illuminance monitor 50 and input to the control unit 150. From the viewpoint of preventing the shadow of the illuminance monitor 50 from being transferred to the wafer W, the illuminance monitor 50 preferably uses a small sensor of about 1 to 2 mm square. As for the wiring, it is preferable that a film is formed on the entire surface of the light transmission member 43 by printing or plating, and a wiring pattern having a width of about 0.2 mm or less is formed by etching or the like. The illuminance monitor 50 is not necessarily provided, and the illuminance may be estimated from the current instruction value to the light emitting element unit 30.

  A reflected light monitor 51 that measures light from the light emitting element unit 30 reflected by the wafer W is positioned above the light transmitting member 43 and on the lower surface of the top plate 11a corresponding to the central portion of the wafer W. Is provided. The reflected light monitor 51 does not detect the irradiation light from the light emitting element unit 30 and can detect the reflected light from the wafer W so that the light receiving portion 51 a is positioned below the lower end surface of the light emitting element unit 30. Has been placed. The reflected light monitor 51 is also connected to the control unit 150 in the same manner as the illuminance monitor 50.

  The control unit 150 is a computer, for example. As shown in FIG. 4, the control unit 150 includes an input unit 151 to which signals from the illuminance monitor 50 and the reflected light monitor 51 are input, a calculation unit 152 to calculate data input from the input unit 151, and predetermined data And an output unit 154 that outputs a signal for controlling the operation of each power supply 40 and other devices.

  The function of the calculation unit 152 will be described in detail. As shown in FIG. 5, the arithmetic unit 152 divides the illuminance S of the light detected by the reflected light monitor 51 input to the input unit 151 by the illuminance U of the light detected by the illuminance monitor 50, so that the wafer is obtained. The ratio of the light reflected by W, that is, the reflectance R of the wafer W is obtained. At this time, the illuminance of light from the light emitting element unit 30 is controlled to be constant, for example, by the first illuminance U. At the same time, based on the correlation Q between the temperature rise curve of the wafer W obtained in advance and the reflectance R of the wafer W, and the reflectance R obtained based on the illuminance S detected by the reflected light monitor 51, the wafer is calculated. An illuminance ΔU to be corrected in order to raise W to a desired temperature is calculated. Then, based on the calculated illuminance ΔU, a current command value to the power supply 40 that supplies current to the light emitting element unit 30 is calculated. The calculated current command value is output from the output unit 154 to each power supply 40.

  The correlation Q will be described. Even when light is emitted from the light emitting element unit 30 to the wafer W with a constant illuminance, the temperature reached by the wafer W varies depending on the surface state of the wafer W, more specifically, the reflectance R of the surface of the wafer W. It will be a thing. The reflectance R of the wafer W varies greatly depending on the type of film formed on the surface of the wafer W. Therefore, even if the illuminance of light from the light emitting element unit 30 is constant at the first illuminance, the reached temperature and the profile of the temperature rise curve vary greatly depending on the reflectance R as shown in FIG. Therefore, it is necessary to appropriately correct the illuminance U of the light irradiated to the wafer W based on the reflectance R and the correlation Q of the wafer W. In FIG. 6, the temperature rises for a silicon wafer W on which no film is formed, a wafer W on which an antireflection film and a TiN film are formed, and a wafer W on which Al is deposited on the surface. The curve is shown.

  The correlation Q is obtained, for example, by a test performed in advance. Specifically, for example, a dummy wafer in which films having various reflectances R are formed on the surface of a dummy wafer having substantially the same diameter as the wafer W in which temperature measuring means such as a thermocouple is incorporated, and each film is formed. The temperature rise curve obtained by irradiating light from the heat source 21 with the first illuminance U and the temperature of the dummy wafer are raised to a desired temperature, that is, the light from the heat source 21 necessary to obtain the desired temperature rise curve. The illuminance is obtained by calculating each film.

  Then, the calculation unit 152 calculates a desired wafer temperature in the wafer W having the reflectance R from the reflectance R of the wafer W and a correlation Q between the temperature rise curve obtained in advance using the dummy wafer and the reflectance R. The illuminance ΔU of the light to be corrected for obtaining is obtained. The correlation Q is stored in the storage unit 153 in advance.

  The storage unit 153 also stores a program for operating the heat treatment apparatus 1 by controlling each power supply 40 and other devices. The above program is recorded on a computer-readable storage medium such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magnetic optical desk (MO), or memory card. May have been installed in the control unit 150 from the storage medium.

  The heat treatment apparatus 1 according to the present embodiment is configured as described above. Next, heat treatment of the wafer W in the heat treatment apparatus 1 according to the present embodiment will be described.

  In the heat treatment of the wafer W, first, the wafer W is loaded into the processing container 11 and is placed and held on the mounting table 10. Next, the inside of the processing container 11 is exhausted through the exhaust pipe 42 and a predetermined processing gas is supplied from the processing gas supply pipe 41. In parallel with this, cooling water is passed through a refrigerant pipe (not shown) inside the top plate 11a.

  Next, a predetermined current command value is output from the output unit 154 of the control unit 150 to each power supply 40, whereby the light is emitted from the light emitting element unit 30 to the wafer W with, for example, the first illuminance U.

  Next, the calculation unit 152 calculates the reflectance R of the wafer W based on the measurement results obtained by the illuminance monitor 50 and the reflected light monitor 51. Next, based on the reflectance R and the correlation Q, the illuminance ΔU to be corrected for heating the wafer W to a desired temperature is calculated. Next, the computing unit 152 obtains the sum of the illuminance ΔU and the illuminance U, and calculates a second illuminance Ux for heating the wafer W to a desired temperature. Thereafter, based on the second illuminance Ux, a current command value to the power source 40 that supplies current to each light emitting element unit 30 is calculated, and the calculated current command value is output from the output unit 154 to the power source 40. The The calculation unit 152 calculates the actual temperature P of the wafer W based on the temperature Tc correlated with the temperature of the wafer W measured by the temperature sensor 20a and the second illuminance Ux irradiated on the wafer W. The actual temperature P, the correlation Q, and the temperature of the wafer W estimated from the illuminance U of the light detected by the illuminance monitor 50 are compared. If a deviation occurs, the deviation is further eliminated. The current command value may be corrected. In other words, even if the wafer W is heated with the corrected second illuminance Ux, if the actual temperature P does not rise along the desired temperature rise curve, the current command value may be corrected as appropriate. Thereby, the current value to each light emitting element unit 30 is controlled, and the wafer W is controlled to a desired temperature, approximately 400 ° C. in the present embodiment. Then, heating is performed at 400 ° C. for 1 minute, and the heat treatment of the wafer W is completed. By this heat treatment, the plasma resistance of the SOC film (not shown) formed on the surface of the wafer W is improved.

  According to the above embodiment, the reflectance R of the wafer W is obtained, and the illuminance of light from the light emitting element unit 30 is calculated from the first illuminance U based on the reflectance R and the correlation Q obtained in advance. Since the illuminance Ux of 2 is corrected, the wafer W can be heated to a desired temperature regardless of the surface state of the wafer W, that is, the reflectance R of the film formed on the surface of the wafer W.

  In the above embodiment, the reflectance R is calculated based on the measurement results of the illuminance monitor 50 and the reflected light monitor 51. However, the method of calculating the reflectance R is not limited to the contents of the present embodiment.

  For example, the reflectance R of the surface of the wafer W is measured in advance by a reflectance measuring device (not shown) provided outside the heat treatment apparatus 1, and the reflectance R is measured before the heat treatment of the wafer W is performed. You may input into the memory | storage part 153. FIG. Further, since the relationship between the illuminance U of the light from the light emitting element unit 30 and the current command value to the power source 40 is known, the relationship between the measured value on the reflected light monitor 51 and the current command value to the power source 40 is simply calculated. The reflectance R may be calculated.

  In the above embodiment, the wafer W is heated by irradiating light from above the wafer W. However, the wafer W may be heated by irradiating light from below the wafer W. The configuration of the heat treatment apparatus in the case where light is irradiated from below the wafer W will be described later.

  In the above embodiment, the reflected light monitor 51 is provided at a position corresponding to the central portion of the wafer W. However, the arrangement of the reflected light monitor 51 is not limited to the contents of the present embodiment. You may provide in the corresponding position of the outer peripheral part vicinity. However, the reflection of light occurs not only on the surface of the wafer W but also on the side surface of the processing container 11, and when measured in the vicinity of the outer peripheral portion of the wafer W, reflection from the processing container 11 may be included. Therefore, the reflected light monitor 51 is preferably provided near the center of the wafer W.

  In the above embodiment, only one reflected light monitor 51 is provided, but a plurality of reflected light monitors 51 may be provided. In such a case, the reflectance R may be calculated according to each reflected light monitor 51, and the output of the light emitting element unit 30 corresponding to the position of the reflected light monitor 51 may be individually controlled. By doing so, for example, even in the case where there are portions having different reflectances in the wafer W surface, the temperature in the wafer W surface can be raised uniformly.

  Examples of the case where the reflectance differs within the wafer W surface include a case where the film thickness of the film formed on the wafer W is not uniform within the wafer W surface. Hereinafter, the control of the output of the light emitting element unit 30 when the reflectance is different in the wafer W plane will be described by taking, for example, the case of using the heat treatment apparatus 100 shown in FIG. In FIG. 7, the heat treatment apparatus 100 that irradiates light from below the wafer W is illustrated. First, the heat treatment apparatus 100 will be described. In the following description, elements having substantially the same functional configuration as those of the heat treatment apparatus 1 are denoted by the same reference numerals, and redundant description is omitted.

  In the heat treatment apparatus 100, the light emitting element unit 30 is disposed at the bottom of the processing container 11, and the light transmitting member 43 is provided above the light emitting element unit 30. The light transmitting member 43 partitions the space inside the processing container 11 into upper and lower parts, and the processing container 11 is partitioned into a heat treatment unit 110 that performs heat treatment on the wafer W and a heat source accommodation unit 111 that accommodates the light emitting element unit 30. Has been.

  A plurality of support pins 112 for supporting the wafer W are arranged on the upper surface of the light transmission member 43, and the wafer W can be supported on the light transmission member 43. The support pins 112 are not always necessary, and the wafer W may be directly placed on the upper surface of the light transmission member 43.

  The light transmission member 43 is connected to an exhaust pipe 42 penetrating through the bottom of the processing container 11, and the atmosphere of the heat treatment part 110 of the processing container 11 can be exhausted through the exhaust pipe 42. it can.

  A plurality of reflected light monitors 51 are arranged at the bottom of the processing container 11. The reflected light monitor 51 does not detect the irradiation light from the light emitting element unit 30 and can detect the reflected light from the wafer W so that the light receiving portion 51 a is located above the upper end surface of the light emitting element unit 30. Has been placed.

  For example, as shown in FIG. 8, the reflected light monitor 51 is disposed at an intermediate position between the three adjacent light emitting element units 30 in plan view. In other words, the arrangement is such that the reflected light corresponding to the three adjacent light emitting element units 30 can be detected by one reflected light monitor 51. In FIG. 8, in order to facilitate the description of the arrangement of the reflected light monitor 51, the number of light emitting element units 30 different from that in FIG. 3 is illustrated. Further, the reason why one reflected light monitor 51 is arranged for three light emitting element units 30 in the present embodiment is to minimize the number of reflected light monitors 51 installed. Therefore, the number and arrangement of the reflected light monitors 51 are not limited to the contents of the present embodiment, and can be set arbitrarily. The illuminance monitor 50 is preferably arranged at a position corresponding to each reflected light monitor 51 from the viewpoint of accurately calculating the reflectance R of the wafer W in a region corresponding to each reflected light monitor 51.

  The heat treatment apparatus 100 according to the present embodiment is configured as described above. In the heat treatment apparatus 100, the wafer W placed on the support pins 112 is irradiated with light with a first illuminance U from each light emitting element unit 30 below the wafer W.

  Next, the computing unit 152 calculates the reflectance R of the region corresponding to each reflected light monitor 51 of the wafer W based on each illuminance monitor 50 and each reflected light monitor 51. The computing unit 152 calculates the second illuminance Ux based on the reflectance R and the correlation Q, and supplies the current to the light emitting element units 30 adjacent to each reflected light monitor 51 based on the second illuminance Ux. Correct the command value. Thereby, even if the film thickness of the film formed on the back surface of the wafer W is not uniform in the wafer W plane, the temperature of the wafer W can be raised uniformly in the plane. The film formed on the back surface of the wafer W includes, for example, a film attached during a CVD (Chemical Vapor Deposition) process performed before the heat treatment, a film formed by plating the wafer W, and the like. is there.

  Next, the inventors conducted a test for heating a wafer W having a diameter of 300 mm using the heat treatment apparatus 1 according to the present embodiment as an example. The test results are shown in FIG. As the wafer W, a silicon wafer W with no film formed on the surface, a wafer W with an antireflection film and a TiN film formed on the surface, and a wafer W with Al deposited on the surface were used. As a condition at this time, the first illuminance was set to an illuminance necessary for obtaining a desired temperature rising curve in a predetermined environment in a silicon wafer W on which no film was formed. Then, the wafer W on which various films are formed is irradiated with light at the first illuminance, and is appropriately corrected to the second illuminance Ux based on the measurement result of the reflected light monitor 51 and the correlation Q. Heating was performed.

  As shown in FIG. 9, in the heat treatment apparatus 1 according to the present embodiment, all wafers W can be heated to substantially the same temperature, and the ultimate temperature is between the wafers W as shown in FIG. It was confirmed that there was no difference. Moreover, the temperature rising curves of the respective wafers W have substantially the same shape, and it has been confirmed that the temperature profile between the wafers W can be made constant.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to this example. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  For example, in the above embodiment, the LED is used as the heat source 21, but the light source used as the heat source 21 is not limited to the LED, and the wafer W as the object to be processed can be heated, that is, absorbed by the wafer W. Any light can be selected as long as it emits light of a wavelength.

  In the above embodiment, the temperature control in the case where the heat treatment of the wafer W is performed by the heat treatment apparatuses 1 and 100 has been described. However, the power supplied to the light emitting element unit 30 is corrected based on the reflectance R of the wafer W. In other words, from the viewpoint of controlling the intensity of light emitted from the light emitting element unit 30, the present invention can be applied to processing other than heat treatment. For example, in the so-called macro defect inspection in which the surface of the wafer W is irradiated with light, and an imaged image of the wafer W is acquired by an imaging device such as a CCD camera, and the presence or absence of defects is inspected based on the imaged image. When the reflectance on the surface of the wafer W is not uniform within the surface, the brightness of the captured image varies. Therefore, even if no defect exists, it may be determined as a defect. In such a case, more accurate macro defect inspection can be performed by providing a plurality of reflected light monitors 51 and calculating the reflectance R for each region as in the present invention.

DESCRIPTION OF SYMBOLS 1 Heat processing apparatus 10 Mounting base 11 Processing container 11a Top plate 11b Hanging part 12 Heat processing part 13 Gas diffusion part 20 Support pin 21 Heat source 30 Light emitting element unit 31 Electrode 32 Support plate 33 Light emitting element 34 Reflective layer 40 Power supply 41 Processing gas supply pipe 42 Exhaust pipe 43 Light transmission member 50 Illuminance monitor 51 Reflected light monitor 150 Control unit 151 Input unit 152 Calculation unit 153 Storage unit 154 Output unit W Wafer R Reflectivity Q Correlation U First illuminance Ux Second illuminance Tc Temperature

Claims (4)

A heat treatment method for heat treating an object to be processed using a plurality of light emitting elements as a heat source,
The object is irradiated with light at a first illuminance from the light emitting element,
Obtain the reflectance of the object to be processed,
Based on the correlation between the reflectance of the object to be processed, and the correlation between the temperature rise curve of the object to be processed and the reflectance of the object to be processed at the first illuminance, which is obtained in advance, Is corrected from the first illuminance to the second illuminance ,
The reflectance of the object to be processed is obtained by measuring the illuminance of light reflected by the object to be processed when light is emitted from the light emitting element with the first illuminance.
The measurement of the illuminance of the light reflected by the object to be processed is performed in a space between the object to be processed and the light emitting element . The light emitting element is disposed at a position facing the back surface of the object to be processed,
The heat treatment method according to claim 1 , wherein the light irradiation from the light emitting element is performed on a back surface of the object to be processed. A heat treatment apparatus for performing heat treatment by irradiating light to an object,
A support member for supporting the object to be processed;
A plurality of light emitting elements that are provided facing the object to be processed supported by the support member and irradiate the object with light;
A controller configured to control the plurality of light emitting elements to irradiate the object to be processed with a first illuminance;
A reflected light monitor that measures the illuminance of light from the light emitting element reflected by the object to be processed;
The control unit is configured to generate the light emission based on the reflectance of the object to be processed and a relationship between a temperature increase curve of the object to be processed and the reflectance of the object to be processed at the first illuminance. Correcting the illuminance of the light from the element from the first illuminance to the second illuminance ;
The control unit obtains the reflectance of the object to be processed based on the illuminance of light measured by the reflected light monitor when light is emitted from the light emitting element at the first illuminance.
The reflected light monitor is arranged to measure illuminance of light from the light emitting element reflected by the object to be processed in a space between the object to be processed and the light emitting element. Heat treatment equipment. The heat treatment apparatus according to claim 3 , wherein the light emitting element is disposed at a position facing a back surface of the object to be processed.