KR20230037930A - Apparatus for processing substrate - Google Patents

Abstract

Provided is a substrate processing apparatus capable of safely and quickly controlling a heater. The apparatus for processing a substrate comprises: a heater including a plurality of heating zones; a sensor unit which senses a temperature of at least one heating zone among the heating zones; and a control unit which calculates a first temperature slope of a first heating zone among the heating zones, in which the first temperature slope is a ratio of a temperature change amount between a first temperature and a second temperature to a time change amount between a first time and a second time, the first temperature is a temperature of a first heating zone at the first time, the second temperature is a temperature of the first heating zone at the second time, and which compares the first temperature slope with a first reference slope to stop an operation of the heater according to a comparison result.

Description

Substrate processing apparatus and method {Apparatus for processing substrate}

The present invention relates to a substrate processing apparatus and method.

When manufacturing a semiconductor device or a display device, various processes such as photography, etching, ashing, ion implantation, thin film deposition, and cleaning are performed. A substrate processing apparatus for performing the above processes may include a heater system for raising the temperature of the chemical liquid, the substrate, and/or the processing space to a target temperature.

In a conventional heater system, when the temperature is not raised to a target temperature within a setting time, it is determined that there is something wrong with the heater system and an interlock is applied. That is, even if there is an abnormality in the power supply or temperature sensor of the heater system, it is possible to detect the abnormality only after the setting time has elapsed. For example, if a temperature sensor for measuring the temperature of a specific location is defective, the controller may determine that the temperature of the specific location is low and continuously raise the temperature of the specific location to cause overheating.

An object to be solved by the present invention is to provide a substrate processing apparatus capable of safely and quickly controlling a heater.

Another problem to be solved by the present invention is to provide a substrate processing method capable of safely and quickly controlling a heater.

The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the following description.

One aspect (aspect) of the substrate processing apparatus of the present invention for achieving the above object is a heater including a plurality of heating zones; a sensor unit sensing a temperature of at least one heating zone among the plurality of heating zones; and calculating a first temperature gradient of a first heating zone among the plurality of heating zones, wherein the first temperature gradient is a temperature between a first temperature and a second temperature with respect to a time change amount between a first time point and a second time point. The ratio of the change amount, the first temperature is the temperature of the first heating zone at the first time point, the second temperature is the temperature of the first heating zone at the second time point, and the first temperature gradient and a control unit that compares with a first reference slope and stops the operation of the heater according to the comparison result.

The first reference slope includes a minimum slope, and the controller may stop the operation of the heater when the first temperature slope is smaller than the minimum slope. Alternatively, the first reference slope includes a maximum slope, and the controller may stop the operation of the heater when the first temperature slope is greater than the maximum slope.

As a result of the comparison, when it is determined that the operation of the heater is normal, the control unit calculates a second temperature gradient of a first heating zone among the plurality of heating zones, wherein the second temperature gradient is the second temperature and the third temperature gradient. The ratio of the temperature change amount between the second temperature and the third temperature to the time change amount between time points, the third temperature is the temperature of the first heating zone at the third time point, and the second temperature gradient It is compared with the first reference slope, and the operation of the heater is stopped according to the comparison result.

Here, a time change amount between the first time point and the second time point and a time change amount between the second time point and the third time point may be equal to each other.

The first time point may be a time point after a predetermined time has elapsed from the start point of temperature increase.

Among the plurality of heating zones, a second heating zone is an unused heating zone, and the controller may stop the operation of the heater when the temperature of the second heating zone exceeds a threshold temperature.

Among the plurality of heating zones, a second heating zone is an unused heating zone, and the control unit calculates a third temperature gradient of the second heating zone, wherein the third temperature gradient is between the fifth time point and the sixth time point. The ratio of the temperature change between the fifth temperature and the sixth temperature to the time change of , the fifth temperature is the temperature of the second heating zone at the fifth time point, and the sixth temperature is the The temperature of the second heating zone at 6 points in time, the third temperature gradient may be compared with the second reference gradient, and the operation of the heater may be stopped according to the comparison result.

One aspect of the substrate processing method of the present invention for achieving the other object is to provide a heater including a plurality of heating zones, wherein the plurality of heating zones include a first heating zone, and at a first point in time, the A first temperature of the first heating zone is measured, a second temperature of the first heating zone is measured at a second time point, and a first temperature gradient of the first heating zone is calculated, wherein the first temperature gradient is The ratio of the temperature change amount between the first temperature and the second temperature to the time change amount between the first time point and the second time point, the first temperature slope is compared with a first reference slope, and the comparison result It may include stopping the operation of the heater according to.

The first reference slope may include a minimum slope or a maximum slope, and the controller may stop the operation of the heater when the first temperature slope is less than the minimum slope or the first temperature slope is greater than the maximum slope. there is.

Among the plurality of heating zones, a second heating zone is an unused heating zone, measures the temperature of the second heating zone at the first time point and the second time point, and the control unit controls the temperature of the first time point or the first time point. When the temperature of the second heating zone measured at two points in time exceeds the limit temperature, the operation of the heater may be stopped.

Details of other embodiments are included in the detailed description and drawings.

1 is a diagram for explaining a substrate processing apparatus according to some embodiments of the present invention.
FIG. 2 is a plan view illustrating a heater installed in the substrate support part of FIG. 1 .
FIG. 3 is a view for explaining an exemplary configuration of a heating zone (eg, Z6) of FIG. 2 .
4 to 6 are diagrams for explaining an operation of a substrate processing apparatus according to some embodiments of the present invention (ie, a heater failure check operation using a heating zone in use).
7 and 8 are diagrams for explaining other operations (ie, a heater failure check operation using an unused heating zone) of the substrate processing apparatus according to some embodiments of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention, and methods for achieving them, will become clear with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms, only the present embodiments make the disclosure of the present invention complete, and the common knowledge in the art to which the present invention belongs It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numbers designate like elements throughout the specification.

The spatially relative terms "below", "beneath", "lower", "above", "upper", etc. It can be used to easily describe the correlation between elements or components and other elements or components. Spatially relative terms should be understood as encompassing different orientations of elements in use or operation in addition to the orientations shown in the figures. For example, when flipping elements shown in the figures, elements described as “below” or “beneath” other elements may be placed “above” the other elements. Thus, the exemplary term “below” may include directions of both below and above. Elements may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation.

Although first, second, etc. are used to describe various elements, components and/or sections, it is needless to say that these elements, components and/or sections are not limited by these terms. These terms are only used to distinguish one element, component or section from another element, component or section. Accordingly, it goes without saying that the first element, first element, or first section referred to below may also be a second element, second element, or second section within the spirit of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description with reference to the accompanying drawings, the same or corresponding components regardless of reference numerals are given the same reference numerals, Description will be omitted.

Although the present invention has been described using a case where a heater having a plurality of heating zones is applied to a bake unit, it is not limited thereto. A heater having a plurality of heating zones may be applied to various equipment, cartridges, etc. in which a substrate support unit is installed.

1 is a diagram for explaining a substrate processing apparatus according to some embodiments of the present invention. FIG. 2 is a plan view illustrating a heater installed in the substrate support unit of FIG. 1 , and FIG. 3 is a diagram illustrating an exemplary configuration of a heating zone (eg, Z6) of FIG. 2 .

First, in FIG. 1 , a bake unit is shown as an example of the substrate processing apparatus 100 . The bake unit is a device for heating a substrate to a process temperature or higher, and may heat the entire area of the substrate to a uniform temperature or adjust the temperature of each area of the substrate according to an operator.

The substrate processing apparatus 100 may include a chamber 110 , an entrance 112 , a substrate support unit 120 , a sensor unit 150 , a control unit 200 , and the like.

The chamber 110 provides a space for heating a substrate therein. During the baking process, the inside of the chamber 110 may be in a normal pressure or reduced pressure atmosphere. An entrance 112 is installed at one side of the chamber 110 , and a wafer for a baking process may be put in or a wafer after a baking process may be taken out through the entrance 112 . Although not separately shown, a peripheral hole for introducing air current (eg, inert gas or air) into the chamber 110 may be formed on a sidewall of the chamber 110 .

A substrate support 120 is disposed in the chamber 110 , and a wafer is seated on the upper surface of the substrate support 120 and subjected to heat treatment.

Referring to FIGS. 2 and 3, a heater is installed in the substrate support 120, and the heater can be divided into a plurality of heating zones (Z1 to Z15), each heating zone (Z1 to Z15) At least one heating member is installed. The heating member may be, for example, a thermoelectric element or a hot wire. The plurality of heating zones Z1 to Z15 may be located on the same plane of the substrate support 120 . In addition, the plurality of heating zones (Z1 ~ Z15) can be independently temperature-controlled. As shown in FIG. 3 , hot wires may be arranged/arranged in a predetermined manner in a heating zone (eg, Z6).

For example, the heating zone Z1 is located at the very center of the substrate support 120, and two heating zones Z2 and Z3 are located to surround the heating zone Z1. In addition, four heating zones Z4, Z5, Z6, and Z7 are positioned to surround the two heating zones Z2 and Z3. Here, in each heating zone (eg Z2), two heating zones (eg Z4 and Z5) may be located. In addition, eight heating zones (Z8 to Z15) are positioned to surround the two heating zones (Z4, Z5, Z6, Z7).

In FIG. 2, it has been described that the heating zones Z1 to Z15 are arranged in four layers (ie, Z1, Z2 to Z3, Z4 to Z7, and Z8 to Z15) by way of example, but it is not limited thereto. That is, the heating zone may be arranged in 3 layers or 5 layers. In addition, in FIG. 2, it has been described that there are two heating zones (eg, Z8 and Z9) corresponding to the outside of each heating zone (eg, Z4), but it is not limited thereto. That is, there may be three or more heating zones corresponding to the outside of each heating zone.

The plurality of heating zones Z1 to Z15 are illustrated as being divided into 15, but are not limited thereto. For example, it may be 16 or more.

In addition, although not separately shown, a plurality of pin holes may be installed on a seating surface (a surface in contact with the substrate) of the substrate support 120 , and lift pins movable in a vertical direction may be provided in the pin holes. The lift pin lifts the substrate or places the substrate on the seating surface of the substrate support 120 .

Referring back to FIG. 1 , the sensor unit 150 senses the temperature of the heater. The sensor unit 150 may include a plurality of sensors. The sensor and the heating zones Z1 to Z15 are matched one-to-one, so that one sensor can sense the temperature of the corresponding one heating zone Z1 to Z15. Alternatively, the sensors and the heating zones Z1 to Z15 are matched one-to-many, so that one sensor can sense the temperatures of two or more corresponding heating zones Z1 to Z15.

The controller 200 calculates temperature gradients of the plurality of heating zones Z1 to Z15 and determines whether the heater is in a normal state based on the calculated temperature gradients. When it is determined that the operation of the heater is abnormal, an interlock may be applied to stop the heater.

A method for determining whether a heating zone in use (ie, a heating zone that is heating up by supplying power) is normal or not may differ from a method for determining whether a heating zone that is not in use (ie, a heating zone without power is supplied) is different from each other. . A method of determining a heating zone in use will be described with reference to FIGS. 4 to 6 , and a method of determining an unused heating zone will be described with reference to FIGS. 7 and 8 .

4 to 6 are views for explaining the operation of a substrate processing apparatus according to some embodiments of the present invention. Hereinafter, a first heating zone (eg, Z6) among a plurality of heating zones will be described as an example.

First, referring to FIG. 4 , the controller 200 calculates the first temperature gradient S _t1t2 of the first heating zone Z6 (S310).

Here, referring to FIG. 5 , the x-axis represents time and the y-axis represents temperature. 5 is a time-temperature relationship shown in the process of starting to supply power to the first heating zone (Z6) at time t0 and adjusting the temperature of the first heating zone (Z6) to the target temperature (Tg) over time It is also

The first temperature gradient S _t1t2 is the first temperature T1 with respect to the time change amount (ie, Δt = t2-t1) between the time t1 (ie, the first time point) and the time t2 (ie, the second time point). It is the ratio of the temperature change amount (ie, ΔT = T2-T1) between T and the second temperature T2. The first temperature T1 is the temperature of the first heating zone Z6 measured at time t1, and the second temperature T2 means the temperature of the first heating zone Z6 measured at time t2.

Therefore, the first temperature gradient S _t1t2 can be calculated using Equation 1 below.

[Equation 1]

S _t1t2 = ΔT / Δt = (T2-T1) / ( t2-t1)

Next, the controller 200 compares the first temperature slope S _t1t2 with the first reference slope, and stops the operation of the heater according to the comparison result (S320, S330, and S340).

Specifically, the first reference slope may include a minimum slope (Smin) and/or a maximum slope (Smax).

The first temperature slope (S _t1t2 ) and the minimum slope (Smin) are compared (S320). If the first temperature slope S _t1t2 is smaller than the minimum slope Smin (YES in S320), it is determined that an abnormality has occurred in the operation of the heater, and an interlock may be applied (S340).

When the first temperature slope S _t1t2 is greater than the minimum slope Smin (NO in S320), the first temperature slope S _t1t2 is compared with the maximum slope Smax (S330). If the first temperature gradient (S _t1t2 ) is greater than the maximum gradient (Smax) (YES in S330 ), it is determined that an abnormality has occurred in the operation of the heater, and the interlock may be applied (S340).

On the other hand, when the first temperature slope S _t1t2 is smaller than the maximum slope Smax (NO in S330 ), it may be determined that the heater operates normally.

Here, the foregoing will be summarized with reference to FIG. 6 . 6 is a diagram for explaining a first temperature gradient S _t1t2 from time t1 to t2.

The minimum slope (Smin) and the maximum slope (Smax) may be values known in advance through a test. That is, when the first temperature slope S _t1t2 moves between the minimum slope Smin and the maximum slope Smax, the temperature of the first heating zone Z6 may reach the target temperature Tg within the setting time.

When the first temperature slope S _t1t2 is less than the minimum slope Smin, the first temperature slope S _t1t2 may have the same slope as S _{t1t2_e1} . If it has the same slope as S _{t1t2_e1} , since the temperature of the first heating zone Z6 rises too slowly, the temperature of the first heating zone Z6 cannot reach the target temperature Tg within the setting time. The reason why the temperature of the first heating zone Z6 rises slowly may be that the power line supplying power to the heating member of the first heating zone Z6 is disconnected. In this case, even if the setting time does not all elapse, it can be known in advance that the first heating zone (Z6) will not be able to meet the target temperature (Tg).

Alternatively, the fact that the first temperature slope S _t1t2 is smaller than the minimum slope Smin may mean a defect different from the above-described one. For example, the temperature may be low due to poor contact between the sensor (ie, the temperature sensor) of the sensor unit 150 and the heating member. Also, the sensor of the sensor unit 150 may be connected to a heating member other than the matching heating member. In these cases, when the first heating zone Z6 is heated until the temperature of the first heating zone Z6 reaches the target temperature Tg, the first heating zone Z6 is overheated.

Accordingly, when the first temperature slope S _t1t2 is smaller than the minimum slope Smin, the controller 200 must stop the operation of the heater.

On the other hand, when the first temperature slope S _t1t2 is greater than the maximum slope Smax, the first temperature slope S _t1t2 may have the same slope as S _{t1t2_e2} . If the slope is the same as S _{t1t2_e2} , since the temperature of the first heating zone Z6 rises too quickly, the first heating zone Z6 may be overheated near the end of the setting time. That is, the temperature of the first heating zone Z6 may be too much higher than the target temperature Tg. Even if the setting time does not all elapse, it can be known in advance that the first heating zone Z6 will be overheated.

Referring to FIGS. 4 and 5 again, when it is determined that the heater operates normally as a result of the examination based on the first temperature gradient (S _t1t2 ) (NO in S330), after a predetermined time elapses, the second temperature gradient ( S _t2t3 ) is calculated (S350).

The second temperature gradient S _t2t3 is the second temperature T2 with respect to the amount of time change (ie, Δt = t3-t2) between the time t2 (ie, the second time point) and the time t3 (ie, the third time point) It is the ratio of the temperature change amount (ie, ΔT = T3-T2) between T and the third temperature T3. The second temperature T2 is the temperature of the first heating zone Z6 measured at time t2, and the third temperature T3 means the temperature of the first heating zone Z6 measured at time t3. The amount of change in time between the time t1 (ie, the first time point) and the time t2 (ie, the second time point) and the amount of change in time between the time t2 (ie, the second time point) and the time t3 (ie, the third time point) are mutually can be the same

Therefore, the second temperature gradient S _t2t3 can be calculated using Equation 2 below.

[Equation 2]

S _t2t3 = ΔT / Δt = (T3-T2) / (t3-t2)

With respect to the second temperature gradient S _t2t3 , it is possible to determine whether or not the heater is abnormal in substantially the same manner as the method performed for the first temperature gradient S _t1t2 . That is, the controller 200 compares the second temperature slope S _t2t3 with the second reference slope and stops the operation of the heater according to the comparison result. The second reference slope may be the same as the first reference slope.

When the second temperature slope S _t2t3 is larger than the minimum slope Smin and smaller than the maximum slope Smax, it is determined that the operation of the heater is normal. On the other hand, when the second temperature slope S _t2t3 is less than the minimum slope Smin or greater than the maximum slope Smax, it is determined that the operation of the heater is abnormal and an interlock is applied.

In this way, the temperature gradient of the first heating zone Z6 may be additionally calculated multiple times until the temperature of the first heating zone Z6 approaches the target temperature Tg. Based on the additionally calculated temperature gradient, it is possible to determine whether or not the first heating zone Z6 is abnormal.

On the other hand, the temperature gradient (ie, S _t1t2 , S _t2t3 , etc.) is calculated from time t1 to tb, and is not calculated from time 0 to t1 or after time tb. Time t1 (ie, the first time point) is a time point after a predetermined time has elapsed since the start of the temperature increase (ie, time t0). Time t1 and time tb may be values learned through a number of tests.

The reason is that, at time t0, the control unit 200 starts to increase the temperature of the first heating zone Z6 by supplying power to the first heating zone Z6. Accordingly, the time t0 to t1 is before the temperature of the first heating zone Z6 is stably increased. From time t0 to t1, the slope is usually too low. The temperature gradient of the first heating zone Z6 calculated at times t0 to t1 is not used as a criterion for determination.

Also, after time tb, since the temperature of the first heating zone Z6 approaches the target temperature Tg, the temperature of the first heating zone Z6 enters the stabilization phase. Therefore, after time tb, the slope is usually too low. The temperature gradient of the first heating zone Z6 calculated after time tb is not used as a criterion for determination.

7 is a diagram for explaining another operation of a substrate processing apparatus according to some embodiments of the present invention. Hereinafter, an unused heating zone (eg, Z7) among a plurality of heating zones will be described as an example.

Referring to FIG. 7 , among the plurality of heating zones Z1 to Z15, the second heating zone Z7 may be an unused heating zone. An unused heating zone means a heating zone to which power is not supplied. The temperature of the unused heating zone should not rise because power is not supplied, but the temperature may rise due to the influence (eg, radiant heat) of the heating zone in use (eg, Z6) disposed in an adjacent area. Therefore, even in an unused heating zone, the temperature cannot but rise at all. However, it is necessary to prevent an error due to excessive temperature rise of an unused heating zone.

The control unit 200 checks the temperature of the second heating zone Z7, which is an unused heating zone, and stops the operation of the heater when the temperature of the second heating zone Z7 exceeds the limit temperature Tℓ (ie, the inter lock occurs).

The control unit 200 determines the temperature of the second heating zone Z7, which is an unused heating zone, at the time of checking the temperature of the first heating zone Z6, which is a used heating zone (ie, time t1, time t2, time t3, etc.) can also be checked.

In FIG. 7 , the temperature of the second heating zone Z7 becomes equal to or higher than the limit temperature Tℓ at time t3, and accordingly, the controller 200 interlocks.

8 is a diagram for explaining another operation of a substrate processing apparatus according to some embodiments of the present invention. Hereinafter, an unused heating zone (eg, Z7) among a plurality of heating zones will be described as an example.

Referring to FIG. 8 , a temperature gradient of an unused heating zone Z7 may be calculated similarly to the heating zone Z6 in use.

That is, the controller 200 calculates the third temperature gradient Q _t1t2 of the second heating zone Z7. The third temperature gradient Q _t1t2 is the ratio of the temperature change between the temperature T11 and the temperature T12 (ie, ΔT = T12-T11) to the time change between the time t1 and the time t2 (ie, Δt = t2-t1) , the temperature T11 is the temperature of the second heating zone Z7 at time point t1, and the temperature T12 is the temperature of the second heating zone Z7 at time point t2.

Therefore, the third temperature gradient Q _t1t2 can be calculated using Equation 3 below.

[Equation 3]

Q _t1t2 = ΔT / Δt = (T12-T11) / (t2-t1)

The controller 200 may compare the third temperature slope Q _t1t2 with the third reference slope and stop the operation of the heater according to the comparison result.

The third reference slope includes "unused reference slope". The unused reference slope may mean "a maximum temperature rise over time that an unused heating zone may rise due to radiant heat or the like." When the third temperature gradient Q _t1t2 is smaller than the non-used reference gradient, it may be determined that the heater is normal.

The reason why the third temperature gradient (Q _t1t2 ) is greater than the non-used reference gradient may be as follows. That is, the sensor of the sensor unit 150 may be connected to a heating member other than the matching heating member. Alternatively, it may be the case that an unused heating member is being heated due to a power supply swap of the heater. Accordingly, it is possible to determine whether the heater is normal based on the third temperature gradient Q _t1t2 .

Similarly, the controller 200 calculates the fourth temperature gradient Q _t2t3 of the second heating zone Z7. The fourth temperature gradient Q _t2t3 satisfies (T13-T12) / ( t3-t2).

Meanwhile, the controller 200 may compare the fourth temperature slope Q _t2t3 with a third reference slope (non-used reference slope) and stop the operation of the heater according to the comparison result.

Although the embodiments of the present invention have been described with reference to the above and accompanying drawings, those skilled in the art to which the present invention pertains can implement the present invention in other specific forms without changing the technical spirit or essential features. You will understand that there is Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting.

100: substrate processing device
110: chamber
112: entrance
120: substrate support
150: sensor unit
200: control unit

Claims (11)

A heater including a plurality of heating zones;
a sensor unit sensing a temperature of at least one heating zone among the plurality of heating zones; and
A first temperature gradient of a first heating zone among the plurality of heating zones is calculated, wherein the first temperature gradient is a temperature change amount between a first temperature and a second temperature with respect to a time change amount between a first time point and a second time point. , wherein the first temperature is the temperature of the first heating zone at the first time point, the second temperature is the temperature of the first heating zone at the second time point, and the first temperature gradient A substrate processing apparatus comprising a control unit that compares the slope with a first reference slope and stops the operation of the heater according to the comparison result. According to claim 1,
The first reference slope includes a minimum slope,
The control unit stops the operation of the heater when the first temperature gradient is smaller than the minimum gradient. According to claim 1,
The first reference slope includes a maximum slope,
The control unit stops the operation of the heater when the first temperature gradient is greater than the maximum gradient. According to claim 1,
As a result of the comparison, when it is determined that the operation of the heater is normal,
The control unit calculates a second temperature gradient of a first heating zone among the plurality of heating zones, wherein the second temperature gradient is based on the amount of change in time between the second and third times, the second temperature and the third temperature gradient. The ratio of the temperature change between temperatures, the third temperature is the temperature of the first heating zone at the third point in time, the second temperature gradient is compared with the first reference gradient, and the heater according to the comparison result Stopping the operation of the substrate processing apparatus. According to claim 4,
A time change amount between the first time point and the second time point and a time change amount between the second time point and the third time point are equal to each other. According to claim 1,
The first time point is a time when a predetermined time has elapsed from the start of the temperature increase, the substrate processing apparatus. According to claim 1,
Among the plurality of heating zones, a second heating zone is an unused heating zone,
The controller stops the operation of the heater when the temperature of the second heating zone is equal to or higher than the limit temperature. According to claim 1,
Among the plurality of heating zones, a second heating zone is an unused heating zone,
The control unit
Calculate a third temperature gradient of the second heating zone, wherein the third temperature gradient is a temperature change amount between the fifth temperature and the sixth temperature with respect to a time change amount between the fifth time point and the sixth time point ratio, the fifth temperature is the temperature of the second heating zone at the fifth time point, the sixth temperature is the temperature of the second heating zone at the sixth time point, and the third temperature gradient is 2 Comparing with a reference slope, and stopping the operation of the heater according to the comparison result. Provide a heater including a plurality of heating zones, wherein the plurality of heating zones include a first heating zone,
At a first time point, a first temperature of the first heating zone is measured,
At a second time point, a second temperature of the first heating zone is measured,
Calculate a first temperature gradient of the first heating zone, wherein the first temperature gradient is a temperature change amount between the first temperature and the second temperature with respect to a time change amount between the first time point and the second time point is the ratio,
comparing the first temperature slope with a first reference slope;
And stopping the operation of the heater according to the comparison result, a substrate processing method. According to claim 9,
The first reference slope includes a minimum slope or a maximum slope,
The control unit stops the operation of the heater when the first temperature gradient is smaller than the minimum gradient or the first temperature gradient is greater than the maximum gradient. According to claim 9,
Among the plurality of heating zones, a second heating zone is an unused heating zone,
At the first time point and the second time point, the temperature of the second heating zone is measured,
The control unit stops the operation of the heater when the temperature of the second heating zone measured at the first time point or the second time point is equal to or higher than the limit temperature.

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