JP2000260726A - Calibration method of substrate heat treating device and calibration device used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the calibration method of a substrate heat treating device with which accurate calibration can be performed, and to provide a calibration device used therefor. SOLUTION: This heating type calibration device 7, retaining the reference substrate SW, wherein a radiation temperature indicator 71 is provided in the vicinity of its center part, is attached to the reflecting plate 123 of a substrate heat treating device 1, and the reference substrate SW is heated by a heater 722 in the calibration device. The quantity of radiated light of multiply reflecting reference substrate SW is measured by a radiation temperature indicator 55 of the substrate heat treating device 1 and the radiation temperature indicator 71 of the heating type calibration device 7, based on the percentage of the quantity of light measured by the radiation temperature indicators 55 and 71. Subsequently, the heating type calibration device 7 is removed, a light emitting part is attached to the upper part of the substrate heat treating device 1, and the substrate is heat-treated. The temperature of the substrate can be measured accurately, using the computed effective reflection factor in this heat treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a semiconductor wafer,
A substrate heat treatment apparatus including a reflector facing a substrate such as a glass substrate for a photomask, a glass substrate for a liquid crystal display, and a substrate for an optical disk (hereinafter, simply referred to as a “substrate”), and a radiation thermometer for measuring the temperature of the substrate. The present invention relates to a method of calibrating the calibration, and a heating type calibration apparatus and a light source type calibration apparatus which can be used in such calibration.

[0002]

BACKGROUND OF THE INVENTION With the miniaturization of semiconductors and the like, high-precision temperature control of a substrate is required in a substrate heat treatment apparatus. Therefore, in order to improve the temperature control of the substrate, the substrate is rotated during the heat treatment to make the temperature distribution of the substrate uniform. It is also effective to measure the temperature of the substrate to be controlled with high accuracy. As a method for measuring the temperature of a substrate rotating during heat treatment in a non-contact manner, a method of measuring, with a radiation thermometer, radiation light of the substrate amplified by the multiple reflection principle has become mainstream. Here, in order to perform accurate temperature measurement, it is necessary to accurately calibrate the substrate heat treatment apparatus for the radiation thermometer prior to the heat treatment.

[0003]

2. Description of the Related Art As the above-mentioned calibration method, the following method is known. First, after a substrate having a known emissivity is inserted into the substrate heat treatment apparatus, the substrate is actually heated and its temperature is measured by a plurality of thermocouples provided at different portions of the substrate, and the output of the radiation thermometer is measured. Then, based on these measured values and the emissivity, the effective reflectance specific to the substrate heat treatment apparatus to be calibrated is obtained.

[0004]

In the above-mentioned conventional calibration method, the temperature of the substrate is measured in a state in which the substrate cannot be rotated because the thermocouple provided on the substrate cannot be rotated and the temperature distribution of the substrate is poor. . Further, the emissivity of the substrate for calibration needs to be accurately determined, but it is not easy to maintain the surface state of the substrate so that the emissivity does not change. Therefore,
The effective reflectance is determined as including a considerable error. As a result, it becomes difficult to measure the temperature of the substrate with high accuracy during the heat treatment.

[0005] The present invention has been made in view of the above problems, and has as its object to provide a new technique for accurately calibrating a substrate heat treatment apparatus.

[0006]

According to a first aspect of the present invention, there is provided a reflector for reflecting heat radiation facing a substrate, and detecting a quantity of light in the vicinity of a reflection surface of the reflector with a main light quantity. A method for calibrating a substrate heat treatment apparatus comprising: a radiation thermometer that measures a substrate temperature by measuring means; and a holding step of holding a predetermined reference substrate in a predetermined state facing the reflection plate; A sub-light amount measuring step of measuring a light amount near a main surface of the reference substrate facing the reflection plate by a sub-light amount detecting unit provided on the reference substrate corresponding to a position of the light amount detecting unit; Calculating a light amount ratio obtained by dividing the light amount measured by the light amount measured by the main light amount detecting means, based on the light amount ratio, the effective light amount corresponding to the characteristic of the reflection plate. Specify the reflectance.

According to a second aspect of the present invention, in the method for calibrating a substrate heat treatment apparatus according to the first aspect, the predetermined state is a state in which the reference substrate is heated.

According to a third aspect of the present invention, in the method for calibrating a substrate heat treatment apparatus according to the first aspect of the present invention, the method further comprises a light supply step of supplying light between the reference substrate and the reflector. The reference substrate has substantially the same optical characteristics as the reflection plate, and has a reflectance as a known characteristic, and the light amount ratio and the reflectance of the reference substrate when light is supplied in the light supply step. The effective reflectance according to the characteristics of the reflector is specified based on

According to a fourth aspect of the present invention, in the method for calibrating a substrate heat treatment apparatus according to the third aspect of the present invention, in the light supply step, the light emitting means provided near the middle between the reference substrate and the reflector. Supplies light from

According to a fifth aspect of the present invention, in the method for calibrating a substrate heat treatment apparatus according to the fourth aspect of the present invention, the light emitting means includes a plurality of spherical elements arranged on a circumference around the auxiliary light quantity detecting means. Light source.

According to a sixth aspect of the present invention, in the method for calibrating a substrate heat treatment apparatus according to the fourth aspect of the present invention, the light emitting means is substantially annularly arranged along a circumference centered on the auxiliary light quantity detecting means. Light source.

According to a seventh aspect of the present invention, the temperature of the substrate is calculated by measuring the amount of light in the vicinity of the reflecting surface of the reflecting plate which reflects heat radiation by facing the substrate with the main light amount detecting means. A calibrating apparatus used when calibrating a substrate heat treatment apparatus including a radiation thermometer, comprising: holding means for holding a predetermined reference substrate facing the reflection plate; and the reference substrate held by the holding means. A sub-light amount measuring a light amount in the vicinity of a main surface of the reference substrate facing the reflection plate by a heating unit that heats the light source and a sub-light amount detection unit provided on the reference substrate corresponding to the position of the main light amount detection unit. Measuring means, and a light amount ratio calculating means for calculating a light amount ratio obtained by dividing the light amount measured by the sub light amount detecting means by the light amount measured by the main light amount detecting means, based on the light amount ratio, Of the reflector Identifying the effective reflectivity corresponding to the sex.

According to a further aspect of the present invention, the temperature of the substrate is calculated by measuring the amount of light in the vicinity of the reflection surface of the reflector by reflecting heat radiation facing the substrate by the main light amount detecting means. A calibration device used when calibrating a substrate heat treatment apparatus including a radiation thermometer, wherein the reference plate having substantially the same optical characteristics as the reflection plate and having a reflectance as a known characteristic faces the reflection plate. Holding means, and a light supply means for supplying light between the reference substrate and the reflection plate,
A sub light quantity measuring means for measuring a light quantity in the vicinity of a main surface of the reference substrate facing the reflection plate by a sub light quantity detecting means provided on the reference substrate corresponding to a position of the main light quantity detecting means; Light amount ratio calculating means for calculating a light amount ratio obtained by dividing the light amount measured by the detecting means by the light amount measured by the main light amount detecting means, and wherein the light is supplied by the light supplying means. Based on the light amount ratio and the reflectance of the reference substrate, an effective reflectance according to the characteristics of the reflector is specified.

According to a ninth aspect of the present invention, in the calibration apparatus for a substrate heat treatment apparatus according to the eighth aspect of the present invention, the light supply means has a light emitting means near an intermediate point between the reference substrate and the reflector.

According to a tenth aspect of the present invention, in the calibration apparatus for the substrate heat treatment apparatus according to the ninth aspect of the present invention, the light emitting means includes a plurality of spheres arranged on a circle around the auxiliary light quantity detecting means. Light source.

According to an eleventh aspect of the present invention, in the calibration apparatus for a substrate heat treatment apparatus according to the ninth aspect of the present invention, the light emitting means is substantially annularly arranged along a circumference centered on the auxiliary light quantity detecting means. Light source.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Outline of Substrate Heat Treatment Apparatus> FIG.
Is a substrate heat treatment apparatus 1 as an example of a calibration object of the present invention.
FIG. The substrate heat treatment apparatus 1 is a rapid heat treatment apparatus for forming an oxide film, a nitride film, and the like on a substrate W, which is a semiconductor substrate, and performing an annealing process.

The substrate heat treatment apparatus 1 has a lid 11 and a main body 12 forming an outer shell of the apparatus, and the lid 11 and the main body 12 have a large number of cooling water channels 13 formed therein.

The lid 11 is provided with a plurality of lamps 21. By irradiating the substrate W with light from the lamps 21, a process involving heating of the substrate W is performed.

A quartz window 30 for partitioning an internal space is disposed between the lid 11 and the main body 12.
A processing space 121 where the substrate W is processed by the quartz window 30 is formed.

A holding mechanism 40 for holding a substrate W to be processed is arranged below the main body 12, and the substrate W loaded into the processing space 121 from a loading / unloading port 122 having an opening / closing mechanism (not shown) is held by the holding mechanism 40. Is held by The holding mechanism 40 is connected to a holding ring 41 that holds the substrate W and surrounds the periphery of the substrate W, a support member 42 that supports the holding ring 41, a transmission mechanism 43 attached below the support member 42, and a transmission mechanism 43. And a motor driver 45 for controlling the driving of the motor 44. With such a configuration, the substrate W held by the holding ring 41 rotates around an axis perpendicular to the main surface under the action of the motor 44.

A reflection plate 123 is disposed below the inside of the main body 12, and radiated light from the substrate W to be heated is reflected by the reflection plate 123.
Radiation thermometer 55 of the temperature measurement mechanism 50 attached to
Is measured by Note that the temperature measurement mechanism 50
Are arranged so as to face substantially the center of the. The output based on the intensity of the emitted light acquired by the temperature measurement mechanism 50 is output to the control unit 6.
Sent to 0.

The control unit 60 includes a CPU, a memory, and the like (not shown), controls the light intensity of the lamp 21 via the lamp driver 22, and controls the motor driver 45.
The processing of the substrate W is controlled by adjusting the motor 44 via the. Further, a drive signal is transmitted at a predetermined timing to a motor driver 56 that supplies electric power to the motor 54.

Next, the configuration of the temperature measuring mechanism 50 will be described.

FIG. 2 is an enlarged longitudinal sectional view showing the vicinity of the temperature measuring mechanism 50 shown in FIG.

The temperature measuring mechanism 50 has a flange 51 attached to the reflection plate 123 and a fixing member 52 attached to the flange 51. A rotating sector 53 that rotates between the flange 51 and the fixing member 52 in a state substantially parallel to the substrate W, a motor 54 that rotates the rotating sector 53, and a cavity 511 (described later) attached to the fixing member 52. Has a radiation thermometer 55 for measuring the intensity of the radiation light incident on the. In addition, as shown in FIG. 1, the radiation thermometer 55 is connected to the control unit 60.

The radiation thermometer 55 is provided with a light guide rod 551 such that its tip is located immediately below the rotating sector 53, and a light amount detector 552 is provided at the other end of the light guide rod 551. The light amount detector 552 is electrically connected to a temperature calculation unit 553 (FIG. 1) including a CPU, a memory, and the like (not shown). Then, the light guide rod 55
1, a radiation intensity signal (radiation energy signal) in which radiation light from the substrate W captured by the light amount detector 552 or a reference substrate SW described later is multiply reflected is converted into a temperature signal and transmitted to the control unit 60.

In the flange 51, a cavity 511 which is a cylindrical hole extending toward the light guide rod 55 is formed at a position corresponding to above the light guide rod 55. The inner surface of the cavity 511 is mirror-finished so as to reflect emitted light. A window member 512 for separating the processing space 121 from the outside of the apparatus is provided below the cavity 511.
Has been fixed.

The fixing member 52 rotatably supports the rotating shaft 531 of the rotating sector 53, and further fixes the radiation thermometer 55 near the rotating shaft 531. The base surface 522 facing the rotating sector 53 on the fixing member 52 is subjected to a blackening process of substantially completely absorbing light without reflecting or transmitting light. Water channels 513 and 521 for cooling are formed inside the flange 51 and the fixing member 52.

FIG. 3 is a plan view of the rotating sector 53.
The rotating sector 53 has a diameter of 4 which is orthogonal to two of the disks.
Two non-adjacent sectors of the equally divided reflector 53
2 are formed. The other fan-shaped portion is a cutout portion 534 which has been removed. The reflecting portion 532 has a mirror-finished surface, and is provided with an arc-shaped slit 533. A rotating shaft 54 of a motor 54 is provided at the center 53C of the rotating sector 53.
1 (see FIG. 2). For this reason, the rotation of the motor 54 allows the rotating sector 53 to rotate freely in a plane parallel to the plate surface.

In the state 1 in which the rotating sector 53 is in the rotating position shown in FIG. 4, since the notch 534 is located above the light guide rod 551, the radiated light from the cavity 511 is blackened. The reflection is suppressed by the base surface 522 and enters the light guide rod 551.

The distance from the center 53C of the rotating sector 53 is equal between the light guide rod 551 and the slit 533. Therefore, in the state 2 rotated by about 90 ° (or about 270 °) from the rotation position of FIG.
2 is located above the light guide rod 551, and the slit 533 is located immediately above the light guide rod 551. Therefore, most of the light emitted from the cavity 511
2, and after multiple reflections with the substrate W, only the radiated light that has passed through the slit 533 enters the light guide rod 551.

As described above, the reflecting portion 532 and the base surface 522 function as a portion near the reflecting surface of the reflecting plate 123, and have two reflecting characteristics (state 1 and state 2) as the rotating sector 53 rotates. Has been created. Therefore,
The following optical analysis of the reflection plate 123 is applied to the reflection portion 532 (FIG. 3) located immediately below the cavity 511 and the portion of the base surface 522 that is exposed to the cavity 511 at that time. Will be.

<Principle of Measuring Temperature of Substrate> FIG.
FIG. 4 is a diagram for explaining multiple reflection of radiated light between a reflection substrate 123 of a substrate heat treatment apparatus 1 and a reference substrate SW which will be described later, unless otherwise specified. As shown in the drawing, light emitted by heating the substrate W is repeatedly reflected between the substrate W and the reflection plate 123. This is called multiple reflection, and the intensity of light received on the reflector 123 side is amplified.

At this time, if the intensity of this light is measured from the reflection plate 123 side, the sum of the downward light is measured. That is, when the measured output is the radiation intensity I, the reflectance of the reflector 123 is R, and the reflectance of the substrate W is ρW (emissivity εW),

[0036]

(Equation 1)

The first term εWLb (T) is a geometric series of the common ratio RρW. Here, Lb (T) is the radiation intensity of the black body at the temperature T. Here, if n is made infinite from RρW <1, then:

[0038]

(Equation 2)

## EQU1 ## Also, assuming that the substrate W does not transmit light,

[0040]

(Equation 3)

The following relationship holds. Therefore, the light amount measured by the light amount detector 552 is the emissivity εW of the substrate W,
Using the temperature T and the reflectance R of the reflector 123,

[0042]

(Equation 4)

Is represented in the form At this time, the reflection plate 1
The reflectivity R of the reflector 23 depends greatly on the shape and surface condition of the reflector 123. Therefore, unlike the simple reflectance obtained only from the material of the reflection plate 123, the reflectance including the shape and the like is referred to as an effective reflectance. And
When the temperature is actually measured by the above-described apparatus configuration, two reflection states (state 1 and state 2) are realized, and the emissivity εW of the substrate W and the temperature T are set as unknowns for each, and the temperature T is set. Ask. Here, in two states,
Since the reflection conditions are different, the effective reflectance is different. In other words, the effective reflectance in each state is R1, R2
By analogy with Equation 4,

[0044]

(Equation 5)

[0045]

(Equation 6)

The following equation holds. Here, I1 and I2 are the radiation intensities measured by the light amount detector 552 in each state, and Lb (T) is known as a function of the temperature. Therefore, by measuring the radiation intensities I1 and I2, The temperature T is determined together with the emissivity εW of the substrate W.

<Main Configuration of Heating Calibration Device of First Embodiment> FIG. 6 shows a heating calibration device 7 of the first embodiment of the present invention.
Is a partial cross-sectional view showing a state in which it is attached to the substrate heat treatment apparatus 1. The heating type calibration device 7 includes a heating type calibration module 70 prepared separately from the substrate heat treatment device 1.
Is mounted on the reflection plate 123 of the substrate heat treatment apparatus 1 to construct a combination of the heating calibration module 70 and a part of the substrate heat treatment apparatus 1.

The heating type calibration module 70 includes a disk-shaped reference substrate SW used for calibration, a radiation thermometer 71 installed near the center of the reference substrate SW, and a heating unit 72 for heating the reference substrate SW. . Here, the radiation thermometer 7
The blackbody radiation intensity characteristic Lb (T) of the device 1 is the same as that of the radiation thermometer 55 of the device 1. Further, an adjustment unit 73 for adjusting the heating of the heating unit 72 and a holding unit 74 for holding the reference substrate SW and the heating unit 72 are further provided.

The radiation thermometer 71 has a light guide rod 711 and a light quantity detector 71 as in the case of the substrate heat treatment apparatus 1.
2 are provided. And the light amount detector 712
It is electrically connected to an arithmetic unit 75 having a PU, a memory, and the like. The arithmetic unit 75 is also electrically connected to the light amount detector 552 of the substrate heat treatment apparatus 1,
Using the radiation intensity signal measured at 2, 712, the reflection plate 1
23 is calculated.

The heating section 72 includes an annular resistance heater 722 provided inside a casing 721, and a heater 72.
2 has a structure in which a heat equalizing plate 723 is provided to be in contact with the lower surface and to be in contact with the upper surface of the reference substrate SW. Further, a thermocouple 724 for measuring the temperature of the reference substrate SW is provided at a position on the lower surface of the heat equalizing plate 723 which is in contact with the reference substrate SW. If the heater 722 is divided into a plurality of zones and is individually heated, the temperature distribution of the reference substrate SW can be made more uniform via the heat equalizing plate 723. For example, the annular heater 722 may be divided into two large and small annular portions between the outer circumference and the inner circumference. Also,
The heating of the reference substrate SW may be heating by light irradiation of a lamp.

The controller 73 includes a temperature controller 731 electrically connected to the thermocouple 724 and a power controller 73 connected to the temperature controller 731 to supply power to the heater 722.
Two. The temperature controller 731 receives the electric signal from the thermocouple 724, calculates the temperature of the reference substrate SW,
Based on this, feedback control for controlling the power regulator 732 to adjust the power supplied to the heater 722 is performed.

The holding section 74 includes a holding member 741 for holding the reference substrate SW and the heating section 72, and a leg 7 for supporting the holding member 741.
42. The leg 742 is connected to the base 743.
And a spacer 744. Here, the spacer 744 is detachable from the base 743,
The holding height of the reference substrate SW can be adjusted.

<Calibration principle and operation of heating type calibration device>
FIG. 7 is a diagram for explaining a calibration principle when the heating-type calibration device 7 is used. Compared to FIG. 5 for explaining multiple reflection, the radiation thermometer 71 and the reflection plate 12 on the side of the reference substrate SW are shown.
A radiation thermometer 55 on the third side is further provided. Other conditions are the same as those in FIG.

In the radiation thermometer 55 of the substrate heat treatment apparatus 1,
Although the downwardly reflected light that is multiply reflected is measured, the heating type calibration device 7 also measures the upwardly directed light. The radiation intensity I ′, which is the sum of the upward light, is

[0055]

(Equation 7)

The following equation holds. Here, Equation 2 and Equation 7
From the relationship, the effective reflectance R is

[0057]

(Equation 8)

Is as follows.

The effective reflectances R 1 and R 2 in the two reflection states in the substrate heat treatment apparatus 1 are given by the following equations.

[0060]

(Equation 9)

The effective reflectance can be calculated by measuring the radiation intensities I1, I2, I'1, and I'2 of the two states.

Next, the operation of the heating type calibration device 7 will be described.

First, before performing the heat treatment of the substrate W, the lid 11 and the quartz window 30 of the substrate heat treatment apparatus 1 are removed.
The leg 742 of the holder 74 is fitted into the groove 123a of the reflection plate 123, and the heating type calibration device 7 is attached. And
The reference substrate SW is heated by the heater 722 to simulate the state during the heat treatment.

Next, in the state 1 (see FIG. 4) in which the rotating sector 53 is not located immediately above the light guide rod 551, the radiated light of the reference substrate SW, which is multiply reflected by the light amount detectors 552 and 712, is measured. At 75, the effective reflectance R1 is calculated. The effective reflectance R1 mainly relates to the base surface 522 of the fixing member 52 that has been subjected to the blackening processing. And
From the state 1 in FIG. 4, the rotating sector 53 is rotated by about 90 °, and the state is switched to the state 2 in which the rotating sector 53 is located immediately above the light guide rod 551, and the effective reflectance R2 is calculated in the same manner as described above. The effective reflectivity R2 mainly relates to the rotating sector 53 that has been mirror-finished. The order of switching between the states 1 and 2 may be reversed.

Then, the heating type calibration apparatus 7 is removed, and the lid 11 and the quartz window 30 are attached to the substrate heat treatment apparatus 1, so that the normal substrate heat treatment apparatus 1 is used. In a normal use state, the substrate W loaded from the loading / unloading port 122
Is held by the holding mechanism 40, and the substrate W is heated by irradiation of light from the lamp 21. In this heating process, accurate measurement of the temperature of the substrate W can be performed by calibrating the measurement characteristics of the radiation thermometer 71 using the calculated effective reflectances R1 and R2 (hereinafter, "thermometer calibration").

In the heating type calibration apparatus 7, the effective reflectance can be obtained without measuring the emissivity εW and the temperature T of the reference substrate SW in principle. Can be reduced. Further, since it is not necessary to maintain the surface state of the substrate as in the related art, it is not necessary to control the atmosphere for maintaining the surface. Further, since it is not necessary to measure the temperature of each portion of the reference substrate SW when calibrating the thermometer, only one thermocouple for measuring the temperature of the reference substrate SW is sufficient, and the maintenance can be easily performed. Is improved.

<Main Configuration of Light Source Type Calibration Apparatus According to Second Embodiment> FIG. 8 shows a light source type calibration apparatus 8 according to a second embodiment of the present invention.
Is a partial cross-sectional view showing a state in which it is attached to the substrate heat treatment apparatus 1. This light source type calibration device 8 includes a light source type calibration module 80 prepared separately from the substrate heat treatment device 1.
Is mounted on the reflection plate 123 of the substrate heat treatment apparatus 1, thereby being constructed as a combination of the light source type calibration module 80 and a part of the substrate heat treatment apparatus 1.

The light source type calibration module 80 includes a disk-shaped reference substrate SW used for calibration, a radiation thermometer 81 installed near the center of the reference substrate SW, the reference substrate SW and the reflection plate 1.
A light-emitting unit 82 that supplies light between the light-emitting device 23 and a holding unit 84 that holds the reference substrate SW.

The reference substrate SW has substantially the same optical characteristics as the reflection plate 123, that is, the same material as the reflection plate 123 and the substantially same reflectance. Also, the reference substrate SW
Is a known characteristic measured in advance.

The radiation thermometer 81 is provided with a light guide rod 811 and a light amount detector 812 as in the heating type calibration device 7. Here, the black body radiation intensity characteristic Lb (T) of the radiation thermometer 81 is the same as that of the radiation thermometer 55 of the device 1. Then, the light amount detector 812
Is electrically connected to an arithmetic unit 85 having a CPU, a memory, and the like. The calculation unit 85 is also electrically connected to the light amount detector 552 of the substrate heat treatment apparatus 1 and calculates the effective reflectance of the reflector 123 using the radiation intensity signals measured by the detectors 552 and 812.

The light emitting section 82 includes the reference substrate SW and the reflection plate 12.
3 and a plurality of spherical lamps 821 located near the intermediate height, and a constant current power supply 8 for supplying power to the lamps 821.
22. This lamp 821 generates a stable light amount by a constant current. Further, the lamp 821 is arranged so that the irradiation light is not multiply reflected and does not directly enter the cavity 511. FIG. 9 is a diagram viewed from the lower surface side of the reference substrate SW, and the plurality of lamps 821 are arranged on the circumference around the light guide rod 811. As for the lamp, the annular lamp 823 may be arranged along the circumference around the light guide rod 811 as shown in FIG.

The holding portion 84 includes a holding member 841 for holding the reference substrate SW, a leg 842 for supporting the holding member 841, and an upper holding member 845 for fixing the upper surface peripheral portion of the reference substrate SW.
It has. The leg 842 has a base 843 and a spacer 844. Here, the spacer 844
Is detachable from the base 843 so that the holding height of the reference substrate SW can be adjusted.

<Calibration principle and operation of light source type calibration device>
FIG. 11 is a diagram for explaining the calibration principle when the light source type calibration device 8 is used. Note that, in this figure, the state of light is equivalent to the left and right, so that the illustration of one light state is omitted for convenience of explanation. In FIG. 11, a lamp 821 is further provided in FIG. 7 for explaining the calibration principle of the calibration device 7. Other conditions are the same as those in FIG. Also, it is considered that the multiple reflection of light contributes to the region MR near the cavity 511 (shown by a parallel virtual oblique line) when measuring the temperature.

When light is introduced from the lamp 821 to the vicinity of the cavity 511, light reaching the boundary MR1 of the region MR becomes light F1 directly reaching the boundary MR1 from the lamp 821,
The reflection is repeated at the reference substrate SW and the reflection plate 123 at the boundary M
Various lights such as light F2 reaching R1 are mixed. Therefore,
As described above, since the optical characteristics of the reference substrate SW and the reflection plate 123 are substantially equal, the light Lup having an upward directional component and the light Ldown having a downward directional component of the light passing through the boundary MR1 are substantially equal. Equal amounts will be present. That is, Lup = Ldown. Next, the multiple reflection of the light Lup and Ldown entering the region MR will be described.

FIG. 12 is an enlarged view of the region MR.
Although not shown, light that has entered the region MR also enters the cavity. The light Lup that has entered the region MR,
Ldown is multiply reflected, and the total Idown of the downward light is
Is

[0076]

(Equation 10)

The following equation holds. Here, RρW <1
If n becomes infinite,

[0078]

[Equation 11]

Is obtained. Since Lup is equal to Ldown as described above, if Lup = Ldown≡L,

[0080]

(Equation 12)

Is expressed as follows. Similarly, the sum of the upward light I
up is expressed by the following equation.

[0082]

(Equation 13)

Therefore, from the relationship of Expressions 12 and 13,
The effective reflectance R is obtained by the following equation.

[0084]

[Equation 14]

The effective reflectances R 1 and R 2 of the two reflection states in the substrate heat treatment apparatus 1 are given by the above equations.

[0086]

(Equation 15)

The effective reflectance can be calculated by measuring the radiation intensities Iup1, Iup2, Idown1, and Idown2 of each of the two states and using the known reflectance ρW of the reference substrate SW.

Next, the operation of the light source type calibration device 8 will be described.

First, before performing the heat treatment on the substrate W, the lid 11 and the quartz window 30 of the substrate heat treatment apparatus 1 are removed, and the light source type calibration apparatus 8 is attached. Then, light is supplied between the reference substrate SW and the reflection plate 123 by the lamp 821.

Next, in the state 1 (see FIG. 3) in which the rotating sector 53 is not located immediately above the light guide rod 551, the multiple reflected light from the lamp 821 is measured by the light amount detectors 552 and 812. Then, using the reflectance ρW of the reference substrate SW, the calculation unit 85 calculates the effective reflectance R1. The effective reflectance R1 mainly relates to the base surface 522 of the fixing member 52 that has been subjected to the blackening processing. Further, from the state 1 in FIG. 3, the rotating sector 53 is rotated by about 90 °, and the rotating sector 53 is positioned just above the light guide rod 551.
And the effective reflectance R2 is calculated in the same manner as described above. This effective reflectivity R2 is mainly determined by the rotational sector 5 that has been mirror-finished.
3 The order of switching between the states 1 and 2 may be reversed.

Then, the heating type calibration apparatus 7 is removed, and the lid 11 and the quartz window 30 are attached to the substrate heat treatment apparatus 1 to restore the normal use state of the substrate heat treatment apparatus 1. Subsequent heat treatment of the substrate is the same as in the case of the heating type calibration device 7 of the first embodiment.

Since the light source type calibration device 8 does not require a heater unlike the heating type calibration device 7, the configuration of the device is simplified.

<Modification> In the above embodiment, the heating type calibration module 70 is used.
Of the black body radiation intensity characteristic Lb (T) is the same between the radiation thermometer 71 installed in the substrate and the radiation thermometer 55 of the substrate heat treatment apparatus 1. However, even in the case of (1), it is possible to separately add a temperature measuring device such as a thermocouple and measure the temperature of the reference substrate SW to perform calibration. As a specific device configuration, a device in which a temperature measuring device such as a thermocouple is attached to the heating-type calibration device 7 can be considered, and the temperature measured by the temperature measuring device is input to the arithmetic unit 75.

Next, the principle of calibration using the heating type calibration module 70 will be described. First, as two different blackbody radiation intensity characteristics Lb (T), the blackbody radiation intensity characteristic Lb1 (T) of the radiation thermometer 55 of the substrate heat treatment apparatus 1 and the radiation thermometer 71 installed in the heating type calibration module 70 are used. Assuming that the blackbody radiation intensity characteristic Lb2 (T) is the output obtained by the radiation thermometer 55,

[0095]

(Equation 16)

And the output obtained by the radiation thermometer 71 is

[0097]

[Equation 17]

Is obtained. Therefore, according to the relationship between Expressions 16 and 17, the effective reflectance is

[0099]

(Equation 18)

This is represented by the following relationship. Therefore, Lb1
Considering that (T) and Lb2 (T) are known in each radiation thermometer, by measuring the temperature of the reference substrate SW using a temperature measuring device such as a thermocouple, the black body at that temperature is measured. Radiation intensity characteristic Lb1 (T) and blackbody radiation intensity characteristic Lb2
(T) and can be calculated,

[0101]

[Equation 19]

As a result, the effective reflectance can be obtained.

◎ As a method of switching the effective reflectance,
As shown in FIG. 13, the rotating sector 5 that has been blackened
3 and the base surface 5 on the mirror-finished fixing member 52
22. Further, as shown in FIG. 14, the surface 53m subjected to the mirror surface treatment and the surface 53
The effective reflectance may be switched by the rotating sector 53 having b.

In the above embodiment, the radiation thermometer 5
5 (71, 81), the light guide rod 551 (711, 811) so that the other end is located immediately below the rotating sector 53.
Is provided at the other end of the light guide rod 551 (711, 811), and the light amount detector 552 (712, 812) is provided. However, the light guide rod 551 (711, 811) and the light amount detector 552 (712) are provided. , 812) may be separated, and the space between them may be connected by an optical fiber or the like.

The lamp 821 (823) of the second embodiment
The reference substrate SW and the reflection plate 123 as shown in FIG.
It is not essential to provide only one step near the intermediate height between
For example, it may be arranged in a two-stage stack near the intermediate height.

The calibration method of each of the above embodiments can be applied not only to the substrate heat treatment apparatus, but also to general temperature measurement of a substrate heat treatment apparatus (for example, CVD) using a combination of a reflection plate and a radiation thermometer. .

[0107]

As described above, according to the first aspect of the present invention, the amount of light near the reflective surface of the reflector and the amount of light near the main surface of the reference substrate facing the reflector are measured. From these light amount ratios, the effective reflectance according to the characteristics of the reflector is specified.

As a result, it is possible to obtain an effective reflectance with a small error according to the characteristic such as the shape of the reflection plate, and it is possible to accurately calibrate the substrate heat treatment apparatus.

According to the second aspect of the present invention, the reference substrate is in a heated state. Therefore, it is possible to simulate the state of heat treatment of the substrate in the substrate heat treatment apparatus,
It is possible to accurately specify the effective reflectance corresponding to the heat treatment.

According to the third aspect of the present invention, light is supplied between the reference substrate and the reflection plate, and the light is reflected on the basis of the light amount ratio in the state where the light is supplied and the reflectance of the reference substrate. The effective reflectance according to the characteristics of the plate is specified. Therefore, simple and accurate calibration of the substrate heat treatment apparatus can be performed.

According to the fourth and ninth aspects of the present invention, since the light emitting means is provided near the middle between the reference substrate and the reflector, the effective reflectance can be obtained more accurately.

According to the fifth and tenth aspects of the present invention, since the light emitting means has a plurality of spherical light sources arranged on the circumference around the auxiliary light amount detecting means, the effective reflection can be more accurately performed. It is possible to determine the rate.

Further, according to the invention of claim 6 and claim 11, since the light emitting means has the substantially annular light source arranged along the circumference centering on the auxiliary light amount detecting means, the effective reflection can be more accurately performed. It is possible to determine the rate.

According to the seventh aspect of the present invention, while the reference substrate is being heated, the amount of light near the reflecting surface of the reflector and the amount of light near the main surface of the reference substrate facing the reflector are measured. From these light quantity ratios, the effective reflectance according to the characteristics of the reflector is specified.

As a result, it is possible to simulate the situation during the heat treatment of the substrate in the substrate heat treatment apparatus, so that it is possible to obtain an accurate effective reflectance corresponding to the time of the heat treatment, and it is possible to accurately calibrate the substrate heat treatment apparatus.

According to the eighth aspect of the present invention, light is supplied between the reference substrate and the reflector, and while the light is supplied, the amount of light near the reflecting surface of the reflector is measured and the light is reflected. The light amount near the main surface of the reference substrate facing the plate is measured. Then, the effective reflectance is specified based on the light amount ratio and the reflectance of the reference substrate. Therefore,
Simple and accurate calibration of the substrate heat treatment apparatus becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a substrate heat treatment apparatus 1 to be calibrated according to the present invention.

FIG. 2 is an enlarged longitudinal sectional view showing a state near a temperature measuring mechanism 50;

3 is a plan view of a rotating sector 53. FIG.

FIG. 4 is a diagram showing a relationship between a rotating sector 53 and a base surface 522.

FIG. 5 is a diagram for explaining multiple reflection of radiation light between a substrate W and a reflection plate 123;

FIG. 6 is a heating-type calibration device 7 according to the first embodiment of the present invention.
Is a partial cross-sectional view showing a state constructed in the substrate heat treatment apparatus 1.

FIG. 7 is a diagram for explaining a calibration principle when a heating-type calibration device 7 is used.

FIG. 8 is a light source type calibration device 8 according to a second embodiment of the present invention.
Is a partial cross-sectional view showing a state constructed in the substrate heat treatment apparatus 1.

FIG. 9 is a diagram viewed from the lower surface side of the reference substrate SW.

FIG. 10 is a diagram viewed from the lower surface side of the reference substrate SW.

FIG. 11 is a diagram for explaining the calibration principle when the light source type calibration device 8 is used.

FIG. 12 is an enlarged view of a region MR.

FIG. 13 is a diagram showing a relationship between a rotating sector 53 and a base surface 522.

14 is a plan view of the rotating sector 53. FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 substrate heat treatment apparatus 7 heating calibration apparatus 8 light source calibration apparatus 50 temperature measurement mechanism 53 rotating sector 55, 71, 81 radiation thermometer 72 heating section 73 adjustment section 74, 84 holding section 75, 85 calculation section 82 light emitting section 123 reflection Plate 511 Cavity 522 Base surface 533 Slit 551, 711, 811 Light guide rod 552, 712, 812 Light intensity detector 722 Heater 723 Heat equalizing plate 821 Lamp I, I ′, Iup, Idown Radiation intensity Lup, Ldown Light from MR lamp Multiple reflection area R, R1, R2 Effective reflectance SW Reference substrate T Substrate temperature W Substrate εW Emissivity of substrate ρW Reflectivity of substrate

Continued on the front page F term (reference) 2G066 AA06 AB02 AB08 AC01 AC11 BA08 BA43 BC15 CA14 CB01 4M106 AA01 AA09 AA20 BA04 CA70 DH02 DH12 DH31 DH39 DH44 DJ19

Claims (11)

[Claims] 1. A substrate comprising: a reflection plate facing a substrate for reflecting heat radiation; and a radiation thermometer for measuring a light amount near a reflection surface of the reflection plate by a main light amount detecting means to calculate a temperature of the substrate. A method of calibrating a heat treatment apparatus, comprising: a holding step of holding a predetermined reference substrate in a predetermined state facing the reflection plate; and detecting a sub light amount provided on the reference substrate corresponding to a position of the main light amount detection unit. Means for measuring the amount of light near the main surface of the reference substrate facing the reflection plate; and measuring the amount of light measured by the amount of auxiliary light by the amount of light measured by the amount of main light. A light amount ratio calculating step of calculating a divided light amount ratio, wherein an effective reflectance according to characteristics of the reflector is specified based on the light amount ratio. 2. The method for calibrating a substrate heat treatment apparatus according to claim 1, wherein the predetermined state is a state in which the reference substrate is heated. 3. The method for calibrating a substrate heat treatment apparatus according to claim 1, further comprising a light supply step of supplying light between said reference substrate and said reflection plate, wherein said reference substrate is optically connected to said reflection plate. Characteristics are almost the same,
And has a reflectance as a known characteristic, and based on the light amount ratio and the reflectance of the reference substrate in a state where light is supplied in the light supply step, an effective reflectance according to the characteristic of the reflection plate. A calibration method for a substrate heat treatment apparatus, wherein the calibration method is specified. 4. The method for calibrating a substrate heat treatment apparatus according to claim 3, wherein in the light supply step, light is supplied from a light emitting unit provided near an intermediate portion between the reference substrate and the reflector. Calibration method for substrate heat treatment equipment. 5. The method for calibrating a substrate heat treatment apparatus according to claim 4, wherein said light emitting means has a plurality of spherical light sources arranged on a circumference around said auxiliary light amount detecting means. Calibration method for substrate heat treatment equipment. 6. The method for calibrating a substrate heat treatment apparatus according to claim 4, wherein said light emitting means has a substantially annular light source arranged along a circumference centered on said auxiliary light amount detecting means. Calibration method for substrate heat treatment equipment. 7. A substrate comprising: a reflection plate facing a substrate for reflecting thermal radiation; and a radiation thermometer for measuring a light amount near a reflection surface of the reflection plate by a main light amount detection unit to calculate a temperature of the substrate. A calibration device used when calibrating the heat treatment device, holding means for holding a predetermined reference substrate facing the reflection plate, heating means for heating the reference substrate held by the holding means, A sub light quantity measuring means for measuring a light quantity near a main surface of the reference substrate facing the reflection plate by a sub light quantity detecting means provided on the reference substrate corresponding to a position of the main light quantity detecting means; Light amount ratio calculating means for calculating a light amount ratio obtained by dividing the light amount measured by the detecting means by the light amount measured by the main light amount detecting means, and according to the characteristics of the reflecting plate based on the light amount ratio Effective reflection Calibration device for the substrate heat treatment apparatus and identifies the. 8. A substrate comprising: a reflection plate facing a substrate for reflecting heat radiation; and a radiation thermometer for measuring a light amount near a reflection surface of the reflection plate by a main light amount detection unit to calculate a temperature of the substrate. A calibration device used when calibrating the heat treatment device, a holding unit that holds a reference substrate having substantially the same optical characteristics as the reflection plate and having a reflectance as a known characteristic, facing the reflection plate, A light supply unit that supplies light between the reference substrate and the reflection plate; and a sub light amount detection unit provided on the reference substrate corresponding to a position of the main light amount detection unit. A sub light quantity measuring means for measuring the light quantity near the main surface of the reference substrate; and a light quantity ratio calculating a light quantity ratio obtained by dividing the light quantity measured by the sub light quantity detecting means by the light quantity measured by the main light quantity detecting means. Means A substrate heat treatment apparatus that specifies an effective reflectance according to characteristics of the reflection plate based on the light amount ratio and the reflectance of the reference substrate in a state where light is supplied by the light supply unit. Calibration equipment. 9. The calibration apparatus for a substrate heat treatment apparatus according to claim 8, wherein said light supply means has a light emitting means near an intermediate point between said reference substrate and said reflection plate. apparatus. 10. The calibration apparatus for a substrate heat treatment apparatus according to claim 9, wherein said light emitting means has a plurality of spherical light sources arranged on a circumference around said auxiliary light amount detecting means. Calibration equipment for substrate heat treatment equipment. 11. The calibration apparatus for a substrate heat treatment apparatus according to claim 9, wherein said light emitting means has a substantially annular light source arranged along a circumference centered on said auxiliary light amount detecting means. Calibration equipment for substrate heat treatment equipment.