JP2000223435A - Substrate temperature detecting method, substrate temperature detecting device, and substrate processing apparatus provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a substrate temperature in a low-temperature range, where accuracy in temperature measurements made by a temperature measuring means becomes lower than allowable accuracy, without keeping the cost unchanged. SOLUTION: When heating is finished (step S3), a substrate is cooled down, and a substrate cooling curve is obtained in approximating manner by the use of the least squares method with respect to the measurement results of substrate temperatures in a prescribed range of temperature higher than the measurable lower limit temperature of a radiation thermometer (step S6). The time required for a substrate to reach to an unloading temperature is obtained by the substrate cooling curve obtained (step S7). As a result of this setup, even without providing a temperature measuring means other than a radiation thermometer is, a substrate temperature lower than a measurable lower limit temperature can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a substrate (hereinafter, simply referred to as a "substrate") such as a semiconductor wafer, a glass substrate for a photomask, a glass substrate for a liquid crystal display, and a substrate for an optical disk during cooling after heat treatment. The present invention relates to a substrate temperature detecting method and a substrate temperature detecting device for detecting a temperature, and a substrate processing apparatus using the same.

[0002]

2. Description of the Related Art RTP (Rap
A rapid heating process called “id Thermal Process” is performed. In such a rapid heating process, a processing gas (for example, a nitrogen gas or an oxygen gas) corresponding to a process is supplied into a processing chamber of the apparatus by a heat treatment apparatus including a plurality of lamps as a heating source, and the processing chamber is provided with such a gas. A series of processes are performed in which the substrate W is heated to a desired processing temperature on the order of seconds while maintaining the same gas atmosphere, maintained at that temperature for a desired time, then turned off the lamp and rapidly cooled.

[0003] Incidentally, in such an apparatus, since it is important to control the temperature of the substrate during the above-described series of processing, a substrate temperature measuring means is usually provided.

For example, there is an apparatus for measuring a temperature during processing by attaching a thermocouple to a substrate. In recent years, in order to improve the in-plane temperature distribution of the substrate, an apparatus for rotating the substrate in a horizontal plane at the time of the heating is mainly used. In such an apparatus, it is impossible to attach a thermocouple to a substrate by contact. Therefore, in such an apparatus, a radiation thermometer called a pyrometer, which measures thermal radiation from a substrate and measures the temperature of the substrate from its intensity, is used as a temperature measuring means.

A pyrometer using a pyroelectric element has a wide measurement temperature range, but is inaccurate in measuring the temperature of a silicon wafer. For this reason, in a heat treatment apparatus that also targets a silicon substrate, a pyrometer using a silicon element whose measurement wavelength is the basic absorption band of silicon is used, so that the direct light of the lamp containing a large amount of light having the wavelength of the basic absorption band of the silicon wafer is used. There is an increasing number of devices that do not target the measurement.

[0006]

By the way, the above RTP
In order to prevent the substrate from being exposed to the atmosphere and oxidizing the thin film on the surface when the substrate is carried out of the apparatus after the heat treatment, a predetermined carrying temperature of about 500 ° C. or less in a low temperature region is adopted. Need to cool down to temperature.

However, the pyrometer of the silicon element cannot accurately measure the temperature in such a low temperature range.
Therefore, in order to determine the timing of unloading, a device that measures the temperature of the substrate in a low-temperature region by providing a pyrometer for a pyroelectric element separately from the pyrometer for the silicon element has been used. In such a device, an extra pyrometer for pyroelectric elements is provided, thus increasing the manufacturing cost of the device.

The present invention is intended to overcome the above-mentioned problems in the prior art, and without increasing costs.
It is an object of the present invention to provide a substrate temperature detection method and a substrate temperature detection device capable of obtaining a substrate temperature in a low temperature region where the temperature measurement accuracy by the temperature measurement means is equal to or less than an allowable accuracy, and a substrate processing apparatus using the same.

[0009]

In order to achieve the above object, the invention of claim 1 is a method of detecting a substrate temperature during cooling after a heat treatment, wherein the method comprises the steps of: Measuring the temperature of the substrate in the high-temperature region, and extrapolating the temperature of the substrate in the low-temperature region where the temperature measurement accuracy by the temperature measuring means is below the allowable accuracy based on the measured temperature of the substrate in the high-temperature region Extrapolation step.

According to a second aspect of the present invention, there is provided the substrate temperature detecting method according to the first aspect, wherein the extrapolating step is performed based on a temperature of the substrate in a high temperature range measured in the measuring step.
Extrapolation is performed using a predetermined nonlinear function.

According to a third aspect of the present invention, there is provided the substrate temperature detecting method according to the first or second aspect, wherein the temperature of the member facing the substrate is approximately determined in a temperature range including a low temperature range. It further comprises a temperature detection step, and the extrapolation step
Extrapolation is performed in consideration of the temperature of the obtained member.

Further, the invention according to claim 4 is a substrate temperature detecting device for detecting the temperature of a substrate at the time of cooling after a heat treatment, wherein the temperature measuring means for measuring the temperature of the substrate in a high-temperature region is provided. Extrapolation means for extrapolating and calculating the temperature of the substrate in a low temperature range where the temperature measurement accuracy by the temperature measurement means is below the allowable accuracy based on the temperature of the substrate in the high temperature range.

According to a fifth aspect of the present invention, there is provided the substrate temperature detecting device according to the fourth aspect, wherein the extrapolating means determines the predetermined temperature based on the temperature of the substrate in the high temperature range measured by the temperature measuring means. Is extrapolated using the nonlinear function of

According to a sixth aspect of the present invention, there is provided the substrate temperature detecting device according to the fourth or fifth aspect, wherein the temperature of the member facing the substrate is approximately determined in a temperature range including a low temperature range. Further comprising a temperature detecting means, the extrapolating means,
Extrapolation is performed in consideration of the temperature of the obtained member.

According to a seventh aspect of the present invention, there is provided a substrate temperature detecting means including the substrate temperature detecting device according to any one of the fourth to sixth aspects, a processing means for performing a predetermined process on the substrate, Control means for controlling the processing by the processing means based on the temperature of the substrate in the low-temperature region extrapolated by the detection means.

Further, the invention according to claim 8 is the substrate processing apparatus according to claim 7, wherein the control means detects the temperature of the substrate in a low temperature region extrapolated by the substrate temperature detecting means. The operation of the next step is started when the temperature reaches the predetermined temperature or when the time required for the substrate to reach the predetermined temperature, which is obtained from the temperature of the substrate, elapses.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

<1. First Embodiment> FIG. 1 is a longitudinal sectional view of a substrate processing apparatus 1 according to a first embodiment of the present invention. Hereinafter, the configuration of this device will be described with reference to FIG. FIG. 1 illustrates the Z axis for ease of explanation.

The substrate processing apparatus 1 of this embodiment mainly includes a processing chamber 10, a substrate holding / rotating section 20, radiation thermometers 30a to 30a.
0c, a temperature detection unit 40 and a control unit 50.

The processing chamber 10 is a cylindrical furnace body composed of an upper light irradiator 11 and a lower furnace wall 12.
Among them, the light irradiation unit 1 corresponding to the light irradiation means of the present invention
1 includes irradiation units 11a to 1 each having a lamp (not shown) and a reflector for reflecting light emitted from the lamp.
1c are embedded, and the irradiation units 11a to 11c
When the substrate emits light, the substrate W is heated by the heat.

A furnace port 12a provided with a shutter 13 that opens and closes is provided on a side surface of the furnace wall 12,
During the heat treatment of the substrate W, the substrate W is carried in and out by an external transfer device (not shown). Above the furnace wall 12 and below the light irradiating section 11, a quartz plate 14 that transmits light from the light irradiating section 11 is disposed substantially horizontally (parallel to the held substrate W surface) so as to cover the opening 12b. Installed. The space between the furnace port 12a and the furnace wall 12 and the space between the quartz plate 14 and the furnace wall 12 are appropriately sealed by an O-ring (not shown).

Further, outside the processing chamber 10, a processing gas supply source PO for supplying a processing gas (for example, nitrogen gas or oxygen gas) used for heat treatment and a chemical gas for replacing the atmosphere in the processing chamber 10 are not provided. Replacement gas supply sources RO for supplying a replacement gas, which is an active gas, are provided, and they are connected to a gas inlet 12c provided in the furnace wall 12 via a pipe P. Further, the pipe P is provided with a three-way valve V so that the processing gas supply source PO and the replacement gas supply source RO can be switched. The furnace wall 12 is provided with an exhaust port 12d for discharging the treated gas,
During the heat treatment of the substrate W, the inside of the processing chamber 10 is filled with a processing gas previously introduced from the gas introduction port 12c, and after the processing, the internal atmosphere is exhausted from the exhaust port 12d.

Further, the reflecting plate 1 is disposed on the bottom surface 12e of the furnace wall 12 so as to face the substrate W with a holding table 22 described later interposed therebetween.
5, and a cooling pipe 12f through which cooling water flows is provided inside the bottom surface 12e.

The substrate holding and rotating unit 20 mainly includes a magnetic coupling 21 which forms a predetermined magnetic field across the bottom of the furnace wall 12 and is magnetically connected to each other, and a substrate W which holds the substrate W.
a holding table 22 for holding at several points by a
The magnetic coupling 21 is rotated by a rotation drive mechanism such as a motor (not shown), and the substrate W is rotated in a horizontal plane by rotating the holding table 22 about the vertical direction (Z-axis direction). . The holding table 22 and the holding member 22a are both made of quartz, and transmit light having a wavelength measured by the radiation thermometers 30a to 30c described below.

The radiation thermometers 30a to 30c are provided so as to penetrate the bottom surface 12e of the furnace wall 12 and the reflection plate 15, and radiate in consideration of the effect of multiple reflection of heat radiation between the substrate W and the reflection plate 15. The intensity (radiant energy) is measured, the substrate temperature is determined based on the intensity, and the temperature signal is sent to the temperature detection unit 40. The radiation thermometers 30a, 30b, and 30c are formed as a set with the irradiation units 11a, 11b, and 11c, respectively. The set includes a central area CA, an intermediate area MA, and an edge area that are areas for controlling the temperature of the substrate W. It is provided so as to correspond to EA.

The temperature detector 40 includes radiation thermometers 30a-30
Upon receipt of the temperature signals from c, the temperature signals are stored, and the temperature of the substrate W after the heat treatment is detected for each of the areas CA, MA, and EA based on the temperature signals. Hereinafter, the temperature detection unit 4
The function of 0 will be described. As shown in FIG. 1, the temperature detection unit 40 has an approximation unit 41 as its function. As described above, radiation thermometers usually have a range in which temperature can be measured with an accuracy that can withstand practical use, and the lowest temperature at which this accuracy can be maintained to some extent is called the measurement lower limit temperature. The temperature range on the low temperature side corresponds to the high temperature range and the low temperature range in the present invention, respectively. Then, the approximation unit 41 measures the substrate W measured in a range (high temperature range) equal to or higher than the lower limit temperature of measurement of the radiation thermometers 30a to 30c.
, A cooling curve (substrate temperature characteristic) of the substrate W showing a relationship between the substrate temperature and the time in a temperature range including a temperature range (low temperature range) equal to or lower than the lower limit temperature of the measurement based on the temperature measurement value of Ask for. That is, the cooling curve is extrapolated to the low temperature side. The details of the processing by the temperature detection unit 40 will be described later.

The control unit 50 includes a CPU and a memory (not shown) therein, each of the irradiation units 11a to 11c, a shutter 13, a rotation driving mechanism, radiation thermometers 30a to 30c,
A radiation thermometer 30 is electrically connected to each part such as the three-way valve V.
The power supplied to the irradiation units 11a to 11c is controlled for each of the areas CA, MA, and EA via a lamp driver (not shown) based on the temperature signals from the respective a to 30c, and the power to the rotary drive mechanism is controlled. The operation of each unit is controlled by controlling the supply, such as rotating the magnetic coupling 21 and opening and closing the shutter 13.

With such a configuration, the substrate processing apparatus 1 performs the following processing. First, the furnace port 12
a while holding the substrate W loaded through the substrate holding rotary unit 20 and filling the processing chamber 10 with the processing gas, while rotating the substrate W in a horizontal plane, the irradiation unit 11a
Heat treatment is performed by irradiating light from １１11c. After the heat treatment for a predetermined time, the irradiation unit 1
Electric power is supplied to the substrates 1a to 11c to emit light, the substrate W is cooled in the processing chamber 10 to a predetermined temperature at which the substrate W can be carried out, and then carried out from the furnace port 12a to the outside. Such a series of processing is repeated for a plurality of substrates W as necessary.

FIG. 2 is a flowchart showing substrate processing according to the first embodiment. Hereinafter, this substrate processing will be described with reference to FIG.

First, an external substrate transfer device (not shown) loads a substrate W into the processing chamber 10 through the furnace port 12a (step S1).

Next, a heating process is performed on the loaded substrate W (step S2). Specifically, the loaded substrates W are held by the substrate holding / rotating section 20, and the processing chamber 10 is filled with the processing gas, and the irradiation units 11a to 11c are rotated while rotating the substrates W in a horizontal plane. Heat treatment is performed by light irradiation.

After the heat treatment for a predetermined time, the heat treatment is terminated (step S3). Specifically, the power supply to the irradiation units 11a to 11c is cut off to stop light emission. Then, the cooling of the substrate W is started (Step S).
4). Hereinafter, the substrate W is cooled in the processing chamber 10 until it is carried out. This is because the temperature of the substrate W is reduced to the unloading temperature predetermined according to the type of the substrate W as described above. During this time, the radiation thermometers 30a to 30c continuously measure the temperature of the substrate W for each of the areas CA, MA, and EA.

Next, a cooling curve of the substrate W is approximately obtained (step S5). Generally, y is the temperature of the substrate W,
Assuming that t is the elapsed time from the start of cooling and a and b are arbitrary constants, the following nonlinear functions are given as candidates for the cooling curve.

[0034]

(Equation 1)

[0035]

(Equation 2)

[0036]

(Equation 3)

In the first embodiment, any one of the cooling curves is stored and set in a memory (not shown) in the approximation unit 41 as a cooling curve to be used in advance.
In addition, as a matter of course, a function other than the above equations 1 to 3 can be set as a cooling curve candidate.

Then, while cooling the substrate W, the substrate temperature is measured for each of the areas CA, MA, and EA as described above. Then, in a predetermined temperature range above the lower limit temperature of measurement of the radiation thermometers 30a to 30c, the measured substrate temperature is stored in a memory (not shown) in the approximation unit 41 for each of the areas CA, MA, and EA. This temperature range is, for example, a temperature range from the lower limit temperature of the measurement to about 50 ° C. on the high temperature side. This substrate temperature is stored in the next step S7.
The purpose of the present invention is to target the substrate temperature only within a predetermined range in order to avoid a delay in processing time and a large storage capacity.

Eventually, the substrate temperature reaches the measurement lower limit of the radiation thermometer (step S6). Then, the optimal constants a and b are obtained by the least squares method using the stored substrate temperature in the above equation (1). Thereby, an approximate cooling curve for detecting (predicting) the substrate temperature can be obtained below.

Next, the arrival time, which is the time required for the substrate temperature to reach the unloading temperature, is determined using the substrate cooling curve obtained by the approximation (step S7).

Then, under control of the control unit 50, the substrate W is cooled while always counting the elapsed time. Then, the arrival time obtained in step S8 elapses (step S8).
8) Since the temperature at which the substrate W can be unloaded has been reached, the control unit 50 first changes the atmosphere in the processing chamber 10 from a processing gas to an external atmosphere so as to be similar to the atmosphere outside the apparatus. Switch to the replacement gas forming the atmosphere. When the gas inside the processing chamber 10 is replaced, the control unit 10
The external transfer device carries out the substrate W out of the processing chamber 10 by the control of (1) (Step S9). As described above, when the substrate W reaches the unloading temperature, the internal atmosphere is replaced or the substrate W is unloaded. Therefore, the replacement gas supply source RO and the external transfer device in the embodiment are used as processing means in the present invention. Equivalent to.

Thus, a series of processes for one substrate W is completed. If there are a plurality of substrates W to be processed, steps S1 to S9 are performed on those substrates W.
Are sequentially repeated.

As described above, according to the first embodiment of the present invention, the radiation thermometer 3 based on the substrate temperature in the high temperature range measured by the radiation thermometers 30a to 30c.
In order to approximately obtain the substrate cooling curve including the relationship between the substrate temperature and the time at or below the measurement lower limit temperature in 0a to 30c, it is necessary to obtain the substrate cooling curve without using any temperature measuring means other than the radiation thermometers 30a to 30c. Therefore, the substrate temperature in the low temperature range can be obtained without increasing the cost.

Further, since the substrate cooling curve is approximately obtained by using a predetermined nonlinear function based on the measured substrate temperature in the high temperature range, the actual substrate temperature can be more improved than when a linear function is used. , A more accurate extrapolation of the substrate temperature can be performed by obtaining a cooling curve close to the distribution.

Further, since the temperature of the substrate W in the low temperature range is extrapolated in consideration of the temperature characteristics of the quartz plate 14 in the temperature range including the low temperature range, the substrate cooling curve can be obtained with high accuracy.

Further, the substrate cooling curve is obtained by the temperature detecting section 40 and the temperature of the substrate W in the low temperature region is extrapolated and obtained.
Based on this, the supply of the replacement gas into the processing chamber 10 and the unloading of the substrate W by the external transfer device are controlled, so that the cost is increased by not using temperature measuring means other than the radiation thermometers 30a to 30c. The processing can be controlled based on the substrate temperature without causing the processing to be performed.

Further, based on the substrate cooling curve obtained by the temperature detecting section 40, the processing chamber 10 is moved into the processing chamber 10 when the temperature reaches the unloading temperature of the substrate W or the time when it is considered that the substrate W reaches the unloading temperature. Since the supply of the gas and the unloading of the substrate W by the external transfer device are performed, the processing can be started at an accurate timing, and high-quality processing can be performed.

<2. Second Preferred Embodiment> FIG. 3 is a longitudinal sectional view of a substrate processing apparatus 2 according to a second preferred embodiment of the present invention. The device configuration of the second embodiment is almost the same as that of the first embodiment. However, the temperature detection unit 40 includes a quartz plate temperature calculation unit 42 in addition to the approximation unit 41. The quartz plate temperature calculation unit 42 calculates the temperature, time, and temperature for the temperature range including the low temperature region of the quartz plate 14 that is the member facing the substrate W when obtaining the substrate cooling curve, as described below in the approximation unit 41. Is approximately determined.

The other configuration of the apparatus is exactly the same as that of the first embodiment.

FIG. 4 is a flowchart showing substrate processing according to the second embodiment. In the following, the second
The substrate processing in the embodiment will be described.

The processing of steps S11 to S14 is the first
Since the processing is the same as that of steps S1 to S4 in the embodiment, the description thereof is omitted.

After the irradiation units 11a to 11c are turned off, the substrate W is cooled while measuring the substrate temperature for each of the areas CA, MA, and EA. Then, in a predetermined temperature range above the lower limit temperature of measurement of the radiation thermometers 30a to 30c, as in the first embodiment, each area CA,
Using the substrate temperature measured for each of MA and EA, a cooling curve is approximately obtained by a sequential least squares method (step S15).

Eventually, the substrate temperature is changed to the radiation thermometers 30a to 30a.
The temperature reaches the measurement lower limit temperature of 0c (step S16). Hereinafter, while detecting (predicting) the substrate temperature every unit time (step S17), the detected substrate temperature value is constantly compared with the unloading temperature.

In the second embodiment, as a method of detecting the substrate temperature per unit time, approximation is performed by the successive least squares method. Specifically, assuming a transfer function indicating the cooling process of the substrate W, the temperature of the substrate W at the next time is approximately determined by using a successive least-squares method per unit time in a subsequent process based on the transfer function. Detect.

As candidates for the transfer function indicating the cooling process, a
When i, bi (i = 0, 1, 2,...), the following can be considered. For example, known as a first-order lag system

[0056]

(Equation 4)

Known as a second-order delay system

[0058]

(Equation 5)

Known as a third-order delay system

[0060]

(Equation 6)

Further, the second-order delay system has been modified.

[0062]

(Equation 7)

Such a transfer function can be considered. The operator z is defined as follows. In general, the Laplace operator s of a continuous time system is expressed by the following equation.

[0064]

(Equation 8)

Here, θ indicates a difference time, and yt indicates an output signal (substrate temperature) at time t. When sampling is performed at equal time intervals, the delay operator z ^-1 is defined by the following equation.

[0066]

(Equation 9)

The recursive least squares method in the second embodiment is performed as follows. In the second embodiment, the equation (4) showing the best match with the measurement result of the substrate temperature obtained by the experiment is used with the output signal yt as the substrate temperature. Hereinafter, the recursive least squares method will be described with reference to the equation (4) as an example. First, assuming that an input signal at time t is xt, a generalized parameter vector θt and a signal vector Zt are defined as follows.

[0068]

(Equation 10)

Here, T represents a transposed matrix. Then, the output signal yts + 1 can be estimated from the measured values of the input signal xt and the output signal yt from the start of measurement to the lower limit temperature of measurement (time ts at which the temperature is reached) by using the successive least squares method. it can. The details of the recursive least squares method are publicly known and will be omitted.

Since the equation of the formula (10) is a recurrence formula relating to the time t, the following equation is obtained from the formula of the formula (10) using the obtained estimated value of the output signal yt-1 before the unit time. t
The output signal yt at the time after the time ts is obtained by advancing the process of obtaining the estimated value of the output signal yt at the time t by the unit time.

However, as is apparent from the equation (10),
When determining the estimated value of the output signal yt, it is necessary to determine the input signal xt. Hereinafter, the input signal xt will be described.

In the second embodiment, the temperature of the quartz plate 14 is used as the input signal xt. That is, the lamps of the irradiation units 11a to 11c are turned off when the substrate W is cooled, and the members that have the highest temperature and affect the temperature of the substrate W during cooling, that is, the members that have the highest thermal correlation with the substrate W Is considered to be a quartz plate 14. Therefore, the temperature of the quartz plate 14 is employed as the input signal xt as described above.

However, in the second embodiment, the temperature of the quartz plate 14 is not measured by a dedicated temperature measuring means. That is, assuming that the transfer function representing the temperature of the quartz plate 14 is a first-order lag system and the heat radiation from the irradiation units 11a to 11c is stopped by the end of heating, the input to the quartz plate 14 at that moment is defined as a delta function. Expressing the inverse Laplace transform with the impulse response, the input signal xt as the temperature of the quartz plate 14 can be approximated by the following equation.

[0074]

[Equation 11]

Here, K represents a gain, τ represents a time constant of the system, and L ⁻¹ represents an inverse Laplace transform, and the time constant τ is obtained in advance by an experiment or the like. The approximation accuracy of the cooling curve by the above-mentioned sequential least squares method is determined by the gain K
It has been experimentally confirmed that the temperature does not largely depend on the absolute value of the temperature of the quartz plate 14, but rather on the time constant τ when the quartz plate 14 is cooled. For this reason, in the second embodiment, the time constant τ of the quartz plate 14 is obtained in advance, and is used when the actual substrate temperature is detected.

As described above, in the temperature detector 40, the quartz plate temperature calculator 42 calculates the input signal xt using the equation (11).
(The temperature of the quartz plate 14) is obtained, and the approximate
1 represents the signal vector Zt, and the output signal yt (substrate temperature) is sequentially obtained from the equation (10). Then, the control unit 50 compares the obtained substrate temperature at each time with the unloading temperature predetermined according to the type of the substrate W.

Eventually, the obtained substrate temperature decreases to the unloading temperature (step S18). Then, the control unit 50
Senses this by the above comparison, and replaces the atmosphere in the processing chamber 10 as in the first embodiment, and the external transfer device unloads the substrate W out of the processing chamber 10 (step S1).
9). Thus, the heating process on the single substrate W is completed. When there are a plurality of substrates W to be processed, steps S11 to S11 are performed on those substrates W.
The process of S19 is sequentially repeated.

As described above, according to the second embodiment, the same effects as those of the first embodiment can be obtained, and the amount of data used for obtaining the substrate temperature after each unit time for performing the successive approximation is small. Therefore, the required storage capacity can be reduced, and the device manufacturing cost can be further reduced.

<3. Modifications> In the first and second embodiments, examples of the substrate processing apparatus, the temperature detection of the substrate, and the substrate processing by the apparatus have been described, but the present invention is not limited to this.

For example, in the first and second embodiments, a curve that best matches the actually measured substrate temperature distribution is obtained by using the least squares method and the sequential least squares method, respectively. Although the substrate temperature is detected in a low temperature range, other approximation methods such as extrapolation using a linear interpolation method or a polynomial interpolation method may be used.

In the first and second embodiments, the gas in the processing chamber 10 is replaced when the arrival time elapses or the unloading temperature has been reached, and the substrate W is unloaded. The gas may be replaced during the cooling in the chamber 10 and the substrate W may be immediately carried out of the processing chamber 10 as the arrival time elapses or the carry-out temperature is reached. Further, for example, when there is another process to be performed at a temperature equal to or lower than the temperature in the predetermined cooling state, the predetermined temperature is predicted by the method of the first and second embodiments, and the lapse of time to reach that temperature or Executing the following processing upon reaching the temperature is also included in the technical scope of the present invention.

In the first and second embodiments, the irradiation units 11a to 11a including lamps as heat sources are used.
c, and the substrate W is heated by the emitted light, but a heating wire heater or the like may be used as a heat source.

Further, in the first embodiment, the substrate W is carried out of the processing chamber 10 with the lapse of the arrival time obtained from the substrate cooling curve. The temperature may be obtained, the temperature may be compared with the unloading temperature, and the substrate W may be unloaded out of the processing chamber 10 when the temperature of the substrate W becomes lower than the unloading temperature.

[0084]

As described above, according to the first to eighth aspects of the present invention, the temperature measurement accuracy of the temperature measuring means is improved based on the temperature of the substrate in the high temperature range measured by the temperature measuring means. In order to extrapolate and determine the temperature of the substrate in the low temperature range below the permissible accuracy, the temperature of the substrate in the low temperature range is obtained without using other temperature measuring means. The temperature can be determined.

According to the second and fifth aspects of the present invention, extrapolation of the temperature of the substrate in the low temperature range is performed using a predetermined nonlinear function based on the measured temperature of the substrate in the high temperature range. Therefore, extrapolation can be performed more accurately than when a linear function is used.

According to the third and sixth aspects of the present invention, the temperature of the substrate in the low temperature range is extrapolated in consideration of the temperature in the temperature range including the low temperature range of the member facing the substrate. The temperature of the substrate in the region can be accurately determined.

According to the seventh and eighth aspects of the present invention, the low-temperature region extrapolated by the substrate temperature detecting means including the substrate temperature detecting device according to any one of the first to sixth aspects is provided. Since the processing by the processing means is controlled based on the temperature of the substrate, no other temperature measuring means is used. Processing can be controlled.

Further, according to the invention of claim 8, based on the temperature of the substrate in the low temperature region extrapolated by the substrate temperature detecting means, the temperature of the substrate reaches a predetermined temperature or is determined by the temperature of the substrate. Since the operation of the next step is started after a lapse of time expected that the substrate to be heated reaches a predetermined temperature, the processing of the next step can be started at an accurate timing, and high-quality processing can be performed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a substrate processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating substrate processing according to the first embodiment.

FIG. 3 is a longitudinal sectional view of a substrate processing apparatus according to a second embodiment of the present invention.

FIG. 4 is a flowchart illustrating substrate processing according to a second embodiment.

[Description of Signs] 1 Substrate processing apparatus 14 Quartz plate 30a to 30c Radiation thermometer (Temperature measuring unit) 40 Temperature detecting unit (Substrate temperature detecting device, Substrate temperature detecting unit) 41 Approximating unit (Extrapolating unit) 42 Quartz plate temperature Calculation unit (member temperature detection unit) 50 Control unit RO Replacement gas supply unit (processing unit) W substrate

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mitsukazu Takahashi 4-chome Tenjin Kitamachi 1-chome, Kamimachi-ku, Kyoto, Japan 1 Dainippon Screen Manufacturing Co., Ltd. (72) Inventor Kiyohiro Sasaki Kyoto 4-chome Tenjin, Kitamachi, Horikawa-dori-Teranouchi, Kamigyo-ku 1 Dainippon Screen Mfg. Co., Ltd. F-term (reference) 2F056 EM00 2G066 AC01 AC16 BA01 BA41 BC15 CA14

Claims (8)

[Claims] 1. A substrate temperature detecting method for detecting a temperature of a substrate at the time of cooling after a heat treatment, comprising: a measuring step of measuring a temperature of the substrate in a high temperature region by a temperature measuring means; An extrapolation step of extrapolating a temperature of the substrate in a low temperature range in which the temperature measurement accuracy of the temperature measurement unit is equal to or less than an allowable accuracy based on the temperature of the substrate. 2. The substrate temperature detecting method according to claim 1, wherein the extrapolating step uses a predetermined nonlinear function based on the temperature of the substrate in the high temperature range measured in the measuring step. And performing the extrapolation. 3. The substrate temperature detecting method according to claim 1, further comprising a member temperature detecting step of approximately calculating a temperature of a member facing the substrate in a temperature range including the low temperature range. Wherein the extrapolation step performs the extrapolation in consideration of the obtained temperature of the member. 4. A substrate temperature detecting device for detecting a temperature of a substrate at the time of cooling after a heat treatment, comprising: temperature measuring means for measuring a temperature of the substrate in a high temperature region; and a measured temperature of the substrate in the high temperature region. Extrapolating means for extrapolating and calculating the temperature of the substrate in a low-temperature region in which the temperature measuring accuracy of the temperature measuring means is equal to or less than the allowable accuracy based on the above. 5. The substrate temperature detecting device according to claim 4, wherein said extrapolating means calculates a predetermined nonlinear function based on a temperature of the substrate in said high temperature range measured by said temperature measuring means. And performing the extrapolation by using the substrate temperature detecting device. 6. The substrate temperature detecting device according to claim 4, further comprising member temperature detecting means for approximately calculating a temperature in a temperature range including the low temperature range of the member facing the substrate. The substrate temperature detecting device, wherein the extrapolating means performs the extrapolation in consideration of the obtained temperature of the member. 7. A substrate temperature detecting means including the substrate temperature detecting device according to claim 4, a processing means for performing a predetermined process on the substrate, and an extrapolated by the substrate temperature detecting means. Control means for controlling processing by the processing means based on the temperature of the substrate in the low temperature range. 8. The substrate processing apparatus according to claim 7, wherein the control unit determines a temperature of the substrate based on a temperature of the substrate in the low temperature region extrapolated by the substrate temperature detection unit. A substrate processing apparatus, wherein the operation of the next step is started when a predetermined temperature is reached or a time required for the substrate to be obtained from the temperature of the substrate is expected to reach the predetermined temperature.