Substrate processing apparatus and substrate processing method

Abstract

To provide a substrate processing apparatus and a substrate processing method, which control the internal temperature of a process tube in a substrate processing process.SOLUTION: A substrate processing apparatus includes a process tube 110 configured to provide a process space in which a processing process for a plurality of substrates 10 laminated in multiple stages is performed, a heater unit 120 to heat the process tube, an internal temperature measuring unit 131 to measure an internal temperature of the process tube, an external temperature measuring unit 132 to measure an external temperature of the process tube, and a control unit to control an output of the heater unit by utilizing the internal temperature of the process tube measured by the internal temperature measuring unit and the external temperature of the process tube measured by the external temperature measuring unit, where the control unit includes a preliminary output value operation unit to operate a preliminary output value of the heater unit by utilizing the measured internal temperature of the process tube, and a correction determination unit to determine whether the preliminary output value of the heater unit is corrected based on the measured external temperature of the process tube.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method, and more particularly, to a substrate processing apparatus and a substrate processing method for controlling the internal temperature of a process tube in a process for a substrate.

Background Art

[0002] A substrate processing apparatus positions a substrate to be processed in a process space and then deposits reaction particles contained in a process gas injected into the process space onto the substrate using a method such as Chemical Vapor Deposition (CVD) or Atomic Layer Deposition (ALD). Examples of such a substrate processing apparatus include a single wafer type substrate processing apparatus capable of performing a processing step on a single substrate and a batch type substrate processing apparatus capable of simultaneously performing a processing step on a plurality of substrates.

[0003] Generally, a batch type substrate processing apparatus accommodates a plurality of substrates in a multi-stage manner in a vertically structured process tube and performs a processing step. Such a batch type substrate processing apparatus can perform a processing step on a plurality of substrates while heating the process tube with an external heater.

[0004] Here, the internal temperature of the process tube in which the substrate is processed (i.e., the temperature of the process space) affects diffusion, deposition, and other heat treatment processes. Matters required for high-quality temperature control include a high heating rate with good temperature uniformity during ramp-up, rapid temperature stabilization with little (or no) overshoot of the temperature, a smaller normal state temperature error band, and a shorter stop time for adjusting control machine parameters.

[0005] Conventionally, single-loop control has been performed via a Proportional-Integral-Derivative (PID) controller, but such single-loop control cannot achieve the required temperature control performance.

[0006] Recently, a Proportional-Integral-Derivative (PID) controller with a Cascade or nested control loop has been used for improved temperature control, but such a conventional approach has practical problems related to complexity and requirements for calculations.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] The present invention provides a substrate processing apparatus and a substrate processing method for effectively controlling the internal temperature of a process tube by controlling the output of a heater unit in a processing step for a substrate.

Means for Solving the Problems

[0009] A substrate processing apparatus according to an embodiment of the present invention includes a process tube that provides a process space in which a process for a plurality of substrates stacked in multiple stages is performed, a heater unit disposed outside the process tube for heating the process tube, an internal temperature measurement unit disposed inside the process tube for measuring the internal temperature of the process tube, an external temperature measurement unit disposed at least partially between the process tube and the heater unit for measuring the external temperature of the process tube, and a control unit that controls the output of the heater unit by utilizing the internal temperature of the process tube measured by the internal temperature measurement unit and the external temperature of the process tube measured by the external temperature measurement unit. The control unit may include a preliminary output value calculation unit that calculates a preliminary output value of the heater unit by utilizing the measured internal temperature of the process tube, and a correction determination unit that determines whether to correct the preliminary output value of the heater unit based on the measured external temperature of the process tube.

[0010] The control unit may further include an output value correction unit that corrects the preliminary output value of the heater unit based on the determination of the correction determination unit.

[0011] The correction determination unit may include a temperature range setting unit that sets a normal control temperature range in which the preliminary output value of the heater unit is used without correction and a correction temperature range in which the preliminary output value of the heater unit is corrected and used, and an external temperature range determination unit that determines which temperature range of the normal control temperature range and the correction temperature range the measured external temperature of the process tube corresponds to.

[0012] The correction temperature range includes a decay temperature range that is a high temperature range higher than the normal control temperature range and a reinforcement temperature range that is a low temperature range lower than the normal control temperature range. The output value correction unit may correct by multiplying the preliminary output value of the heater unit by a decay coefficient that is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature range in the decay temperature range, and may correct by adding a reinforcement value that is proportional to the temperature drop width with respect to the lower limit of the normal control temperature range in the reinforcement temperature range to the preliminary output value of the heater unit.

[0013] The heater unit heats the process tube and maintains it at a standby temperature, maintains the process temperature during the processing step after raising the temperature from the standby temperature to the process temperature, and the normal control temperature range and the correction temperature range may have different temperature ranges for each of the standby temperature section, the temperature increase section, and the process temperature section.

[0014] The preliminary output value calculation unit may perform proportional-integral-derivative (PID) calculation by utilizing the measured internal temperature of the process tube.

[0015] A substrate processing method according to another embodiment of the present invention includes a process of heating the process tube by a heater unit disposed outside the process tube, a process of measuring the internal temperature of the process tube using an internal temperature measurement unit, a process of measuring the external temperature of the process tube using an external temperature measurement unit, and a process of controlling the output of the heater unit by utilizing the measured internal temperature and external temperature of the process tube. The process of controlling the output of the heater unit may include a process of calculating a preliminary output value of the heater unit by utilizing the measured internal temperature of the process tube, and a process of determining whether to correct the preliminary output value of the heater unit based on the measured external temperature of the process tube.

[0016] The substrate processing method may further include a process of correcting the preliminary output value of the heater unit when it is determined to correct the preliminary output value of the heater unit in the process of controlling the output of the heater unit.

[0017] The substrate processing method further includes a process of setting a normal control temperature range that is used without correcting the preliminary output value of the heater unit, and a process of setting a correction temperature range that is used by correcting the preliminary output value of the heater unit. The process of determining whether to correct the preliminary output value of the heater unit may include a process of determining whether the measured external temperature of the process tube corresponds to either the normal control temperature range or the correction temperature range.

[0018] The process of setting the correction temperature range includes a process of setting a decay temperature range in a temperature range higher than the normal control temperature range and a process of setting a reinforcement temperature range in a temperature range lower than the normal control temperature range. The process of correcting the preliminary output value of the heater unit includes multiplying the preliminary output value of the heater unit by a decay coefficient that is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature range when the measured external temperature of the process tube corresponds to the decay temperature range, and adding a reinforcement value proportional to the temperature drop width with respect to the lower limit of the normal control temperature range to the preliminary output value of the heater unit when the measured external temperature of the process tube corresponds to the reinforcement temperature range. It may also include a correction process.

[0019] The process of heating the process tube includes a process of heating and holding the process tube at a standby temperature, a process of raising the temperature from the standby temperature to a process temperature, and a process of holding the process temperature during a processing step for a substrate. The normal control temperature range and the correction temperature range may have different temperature ranges for each process in the process of heating and holding at the standby temperature, raising the temperature to the process temperature, and holding the process temperature.

[0020] The process of calculating the preliminary output value of the heater unit may include a process of performing a proportional-integral-derivative (PID) calculation using the measured internal temperature of the process tube.

Advantages of the Invention

[0021] The substrate processing apparatus according to an embodiment of the present invention can quickly determine (or calculate) the output of the heater unit by a single-loop operation by calculating a preliminary output value of the heater unit using the measured internal temperature of the process tube. Further, based on the measured external temperature of the process tube, it is determined whether to correct the preliminary output value of the heater unit. When it is determined that correction is necessary, the preliminary output value of the heater unit is corrected, thereby preventing and / or suppressing a sudden output of the heater unit while keeping the difference between the internal temperature and the external temperature of the process tube within a certain level. As a result, while quickly determining the output of the heater unit, it is possible to prevent and / or suppress the peeling (lift-up) of the by-product film in the process tube and the generation of particles caused by this, which occur as the difference between the internal temperature and the external temperature of the process tube increases due to a sudden output of the heater unit. That is, the single-loop operation using the internal temperature of the process tube can achieve the same effect as the output control of the heater unit using a cascade dual-loop operation.

[0022] On the other hand, when each component of the substrate processing apparatus is made of a material having a different coefficient of thermal expansion, a large difference between the internal temperature and the external temperature of the process tube increases the secular change rate of each component, and as a result, shortens the life of each component. However, in the substrate processing method of the present invention, it is possible to prevent and / or suppress the difference between the internal temperature and the external temperature of the process tube from being kept at a level where the secular change rate does not increase and the life of each component is shortened due to a high secular change rate.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0024] Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and should be embodied in various different forms. These embodiments are provided merely to make the disclosure of the present invention complete and to fully inform those with ordinary knowledge of the scope of the invention. For ease of explanation, the components in the drawings may be exaggerated or reduced. In describing the present invention, the same reference numerals are assigned to the same components, and the drawings may be partially exaggerated in size to accurately explain the embodiments of the present invention. In the drawings, the same reference numerals indicate the same components.

[0025] FIG. 1 is a schematic cross-sectional view showing a substrate processing apparatus according to an embodiment of the present invention.

[0026] Referring to FIG. 1, a substrate processing apparatus 100 according to an embodiment of the present invention may include a process tube 110 that provides a process space in which a processing step is performed on a plurality of substrates 10 stacked in multiple stages, a heater unit 120 disposed outside the process tube 110 for heating the process tube 110, an internal temperature measurement unit 131 disposed inside the process tube 110 for measuring the internal temperature of the process tube 110, an external temperature measurement unit 132 disposed at least partially between the process tube 110 and the heater unit 120 for measuring the external temperature of the process tube 110, and a control unit 140 that controls the output of the heater unit 120 by utilizing the internal temperature of the process tube 110 measured by the internal temperature measurement unit 131 and the external temperature of the process tube 110 measured by the external temperature measurement unit 132.

[0027] The process tube 110 can provide a process space where a processing process for a plurality of substrates 10 stacked in multiple stages inside is performed, and a plurality of substrates 10 can be accommodated in the process space so that the processing process can be performed. For example, the process tube 110 can be formed of a heat-resistant material such as quartz or ceramic in a cylindrical shape with a closed upper part and an open lower part, extends in the vertical direction, and can accommodate a substrate boat in which a plurality of substrates 10 are stacked in the longitudinal direction (or the extending direction) of the process tube 110, and an actual processing process (for example, a vapor deposition process) can be performed. Here, the substrate boat is a component for supporting a substrate 10 such as a wafer, and may be formed such that a plurality of substrates 10 are stacked in the longitudinal direction (that is, the vertical direction) of the process tube 110, or a plurality of unit processing spaces in which a plurality of substrates 10 are individually processed may be formed.

[0028] The heater unit 120 can heat the process tube 110 and can be disposed outside the process tube 110 to transfer (or dispose) thermal energy to the process tube 110. For example, the heater unit 120 may include a plurality of heaters disposed so as to wrap the process tube 110 at different heights so as to selectively heat different regions of the process space at different heights. In the case of a vertical batch type substrate processing apparatus 100 that processes a plurality of substrates 10 simultaneously, since the length of the process tube 110 may reach several meters (m) so that a large number of substrates 10 can be placed, in order to finely control the temperature of the process space inside the process tube 110, it can be divided into a large number of zones and selectively heated using the plurality of heaters.

[0029] The internal temperature measurement unit 131 can be disposed inside the process tube 110 and can measure the internal temperature of the process tube 110 (i.e., the temperature of the process space). For example, the internal temperature measurement unit 131 is rod-shaped and is arranged to extend along the inner wall of the vertically extending process tube 110, so that the internal temperature of the process tube 110 can be measured for different height regions, and it may be provided with a temperature profile thermocouple (TC) that can measure the temperature profile. The lower part can be supported by a flange that supports the process tube 110 and can also be connected to the outside through the flange. On the other hand, for a thermocouple (TC), it is joined at one end of another type of metal wire to form a contact part. When both ends maintain different temperatures, an electromotive force is generated. By setting one end of one side to a constant temperature and the other end to various temperatures and measuring the electromotive force, the temperature of the contact part can be inferred.

[0030] Also, the internal temperature measurement unit 131 can be inserted vertically into the process space inside the process tube 110. The thermocouples are configured in multiple numbers, and the contact parts of each thermocouple are arranged corresponding to the heights of different regions of the process space, so that the temperatures of different height regions can also be measured. At this time, based on the temperatures of different height regions measured by the multiple thermocouples, the output (or heat generation amount) of each of the multiple heaters can be individually controlled by the control unit 140. Here, in some cases, it is preferable that the internal temperature measurement unit 131 is arranged at a position closest to the substrate 10 which is the object to be processed.

[0031] The external temperature measurement unit 132 can be disposed at least partially between the process tube 110 and the heater unit 120, and can measure the external temperature of the process tube 110 within the heater unit 120 (i.e., the temperature of the space between the heater unit and the process tube). Here, by measuring (or reading) the external temperature of the process tube 110, the external temperature measurement unit 132 can monitor the heating temperature of the heating element (Heat-Element) such as the plurality of heaters in the heater unit 120, and can play an important role as a reference temperature when the heater unit 120 reaches a thermally stable state, and can be utilized as feedback temperature information regarding the heat transfer state during temperature rise. For example, the external temperature measurement unit 132 may include a rod-shaped spike thermocouple (TC), which can be inserted from the outside of the heater unit 120 and one end thereof can be disposed in the space between the process tube 110 and the heater unit 120 (e.g., around the process tube or within a distance of 5 to 20 mm from the process tube), and can measure the temperature of the space between the process tube 110 and the heater unit 120 (or around the process tube) (i.e., the external temperature of the process tube). On the other hand, the spike thermocouple (TC) can be configured in a plurality and disposed so as to correspond to the height of each region of the process space.

[0032] At this time, since the internal temperature measurement unit 131 and the external temperature measurement unit 132 are separated by the quartz material process tube 110, they usually should not be at the same temperature, and due to heat loss and heat transfer delay caused by the process tube 110, their temperatures may be different even in a stabilized state (or a thermal equilibrium state).

[0033] The control unit 140 can control (or adjust) the output of the heater unit 120 by utilizing the internal temperature of the process tube 110 measured by the internal temperature measurement unit 131 and the external temperature of the process tube 110 measured by the external temperature measurement unit 132. The measured internal temperature of the process tube 110 can be utilized (or used) for calculating a preliminary output value of the heater unit 120 to promptly adjust the internal temperature of the process tube 110 to a target temperature (or set temperature). The measured external temperature of the process tube 110 can be utilized for determining (or judging) whether to correct the preliminary output value of the heater unit 120 and / or the correction ratio of the preliminary output value of the heater unit 120. Based on the determination of whether to correct the preliminary output value of the heater unit 120 using the measured external temperature of the process tube 110, the output of the heater unit 120 can be controlled by directly using the preliminary output value of the heater unit 120 as the output of the heater unit 120 or by correcting the preliminary output value of the heater unit 120 and using it as the output of the heater unit 120.

[0034] FIG. 2 is a conceptual diagram for explaining a control unit according to an embodiment of the present invention.

[0035] Referring to FIG. 2, the control unit 140 may include a preliminary output value calculation unit 141 that calculates a preliminary output value of the heater unit 120 by utilizing the measured internal temperature of the process tube 110, and a correction determination unit 142 that determines whether to correct the preliminary output value of the heater unit 120 based on the measured external temperature of the process tube 110. The preliminary output value calculation unit 141 can calculate (or compute) a preliminary output value of the heater unit 120 by utilizing the measured internal temperature of the process tube 110, and can calculate a preliminary output value of the heater unit 120 for adjusting the internal temperature of the process tube 110 to the target temperature. By calculating only using the measured internal temperature of the process tube 110, the preliminary output value of the heater unit 120 can be calculated quickly, and the output of the heater unit 120 can be calculated (or determined) at high speed by single-loop operation. In addition, the measured internal temperature of the process tube 110 can represent the temperature closest to the substrate 10, and by controlling the output of the heater unit 120 using the preliminary output value of the heater unit 120 calculated (or computed) by utilizing this, an accurate process temperature can be provided to the substrate 10, and the process film quality can be made uniform.

[0036] Here, the preliminary output value calculation unit 141 can perform proportional-integral-derivative (PID) operation by utilizing the measured internal temperature of the process tube 110. The preliminary output value calculation unit 141 can perform proportional-integral-derivative (PID) operation so that the measured internal temperature of the process tube 110 matches the target temperature, and the control unit 140 can perform proportional-integral-derivative (PID) control using the preliminary output value of the heater unit 120 obtained by performing proportional-integral-derivative (PID) operation, and the output of the heater unit 120 can be adjusted according to the control of the control unit 140.

[0037] For example, the preliminary output value calculation unit 141 may include a differential module, an integral operation module, and a proportional operation module. The differential module can calculate a differential operation on the difference value using a differential constant (k d ) value calculated from the difference between the target temperature and the measured internal temperature of the process tube 110, and can determine the rate of change of the difference value.

[0038] The integral operation module can calculate an integral constant (k i ) from the difference between the target temperature and the measured internal temperature of the process tube 110 and perform addition. At this time, the output of the differential module can also be used as an input for calculating the integral operation of the integral operation module.

[0039] The proportional operation module can calculate a proportional operation using a proportional constant (k p ) calculated from the difference between the target temperature and the measured internal temperature of the process tube 110 and the outputs of the differential module and the integral operation module.

[0040] The correction determination unit 142 can determine whether to correct the preliminary output value of the heater unit 120 based on the measured external temperature of the process tube 110. Through this, the output of the heater unit 120 can be prevented from exceeding the maximum value, and the internal temperature of the process tube 110 can be prevented from dropping below a specific temperature.

[0041] As in the past, if control is performed only based on the internal temperature of the process tube 110 measured by the internal temperature measurement unit 131, since the positions of the heater unit 120 and the internal temperature measurement unit 131 are (relatively) separated and heat has to be transferred through internal structures such as the process tube 110, a delay in heat transfer occurs, and thus there is a risk that the difference between the internal temperature of the process tube 110 and the external temperature of the process tube 110 will increase. In particular, when the substrate 10 is loaded or when the temperature is raised and lowered, rather than in a normal steady-state where the same temperature is maintained, there is a risk that the difference between the internal temperature of the process tube 110 and the external temperature of the process tube 110 will become (even) more severe. In such a case, there is a risk that the by-product film accumulated inside the process tube 110 due to a previously performed process will be lifted up, causing the generation of particles around the substrate 10. Not only such problems, but also the deep part and the outside of the inside of the heater unit 120 have different temperatures, resulting in a rapid temperature difference, and the secular change rate of the components (or accessories) constituting the substrate processing apparatus 100 due to the separation of materials having different coefficients of thermal expansion is increased, and ultimately the life is shortened.

[0042] Therefore, the substrate processing apparatus 100 according to the present invention calculates a preliminary output value of the heater unit 120 by utilizing the measured internal temperature of the process tube 110, so that the output of the heater unit 120 can be quickly determined (or calculated) by single-loop calculation. However, based on the measured external temperature of the process tube 110, it is determined whether the preliminary output value of the heater unit 120 needs to be corrected. If it is determined that correction is required, the preliminary output value of the heater unit 120 is corrected, thereby preventing and / or suppressing a sudden output of the heater unit 120 while keeping the difference between the internal temperature and the external temperature of the process tube 110 within a certain level. As a result, while the output of the heater unit 120 can be determined at high speed, it is possible to prevent and / or suppress the peeling of the by-product film in the process tube 110 and the generation of particles caused by this peeling, which would otherwise result in a large difference between the internal temperature and the external temperature of the process tube 110 due to the sudden output of the heater unit 120.

[0043] That is, based on the control utilizing the internal temperature of the process tube 110 measured by the internal temperature measurement unit 131 (or in view of the control), a guide function using the external temperature of the process tube 110 is simultaneously realized to prevent over-temperature and / or low temperature of the external temperature of the process tube 110. At the same time, the output determination (parameter setting) time of the heater unit 120 can be shortened by an amount comparable to that when controlling only by the internal temperature of the process tube 110, and the accuracy of temperature control can be maintained at a level comparable to that of cascade dual-loop control. Therefore, the substrate processing apparatus 100 according to the present invention can achieve the same effect as the output control of the heater unit 120 using cascade dual-loop calculation even by single-loop calculation utilizing the internal temperature of the process tube 110.

[0044] Also, it is possible to prevent and / or suppress the reduction of the life of each component of the substrate processing apparatus 100 due to a high aging rate by maintaining the difference between the internal temperature and the external temperature of the process tube 110 at a level where the aging rate does not increase.

[0045] And the control unit 140 may further include an output value correction unit 143 that corrects the preliminary output value of the heater unit 120 based on the determination of the correction determination unit 142. The output value correction unit 143 can correct the preliminary output value of the heater unit 120 based on the determination of the correction determination unit 142, and can correct the preliminary output value of the heater unit 120 only when determining the correction of the preliminary output value of the heater unit 120. Through this, the output value correction unit 143 can obtain (or calculate) the (final) output value of the heater unit 120, and can deliver an output signal based on the (final) output value of the heater unit 120 to the heater unit 120, whereby the output of the heater unit 120 can be controlled.

[0046] Here, the preliminary output value of the heater unit 120 and the (final) output value of the heater unit 120 can be indicated in %, and are values indicating a ratio between 0 and the maximum output of the heater unit 120, and may be a ratio (%) with respect to the maximum output of the heater unit 120. For example, when it is 100%, it may be the maximum output of the heater unit 120, and when it is 0%, the output of the heater unit 120 may be 0 (or off).

[0047] FIG. 3 is a conceptual diagram for explaining the normal control temperature range, the attenuation temperature range, and the reinforcement temperature range according to an embodiment of the present invention.

[0048] Referring to FIG. 3, the correction determination unit 142 may include a temperature band setting unit that sets a normal control temperature band in which the preliminary output value of the heater unit 120 is used without correction and a correction temperature band in which the preliminary output value of the heater unit 120 is corrected and used, and an external temperature band determination unit that determines whether the measured external temperature of the process tube 110 corresponds to either the normal control temperature band or the correction temperature band. The temperature band setting unit can set a normal control temperature band (band) in which the preliminary output value of the heater unit 120 is used without correction and a correction temperature band in which the preliminary output value of the heater unit 120 is corrected and used. Here, in the normal control temperature band, the preliminary output value of the heater unit 120 can be used as the output of the heater unit 120 without correction, and in the correction temperature band, the preliminary output value of the heater unit 120 can be corrected and used as the output of the heater unit 120 (the corrected output value of the heater unit).

[0049] For example, the normal control temperature band may be a temperature band that is not excessively high and not excessively low, and may be a temperature band within a predetermined range (or error range) above and below the set temperature (or the target temperature) including the set temperature by time (or by time point), or may be a temperature (range) in a thermally stable state. And the correction temperature band may be a temperature band that is excessively high or excessively low, may be a temperature band that is outside the predetermined range above and below the set temperature and is high or low, or may be a temperature (range) in a thermally unstable state. Thereby, in the normal control temperature band, even if the preliminary output value of the heater unit 120 is used as the output of the heater unit 120 without correction, the external temperature of the process tube 110 does not become over-temperature due to the high output, and the internal temperature of the process tube 110 can be prevented from dropping below a specific temperature.

[0050] The external temperature band determination unit can determine which temperature band of the normal control temperature band and the correction temperature band the measured external temperature of the process tube 110 corresponds to. When the measured external temperature of the process tube 110 corresponds to the normal control temperature band, non-correction of the preliminary output value of the heater unit 120 can be determined (or judged). When the measured external temperature of the process tube 110 corresponds to the correction temperature band, correction of the preliminary output value of the heater unit 120 can be determined (or judged).

[0051] The correction temperature band may include an attenuation temperature band in a higher temperature range than the normal control temperature band and a reinforcement temperature band in a lower temperature range than the normal control temperature band. The attenuation temperature band may be a higher temperature band than the normal control temperature band. When the measured external temperature of the process tube 110 corresponds to the attenuation temperature band, the preliminary output value of the heater unit 120 can be corrected so that the external temperature of the process tube 110 does not become over-temperature due to the high output of the heater unit 120, and it can be corrected by attenuating lower than the preliminary output value of the heater unit 120.

[0052] The reinforcement temperature band may be a lower temperature band than the normal control temperature band. When the measured external temperature of the process tube 110 corresponds to the reinforcement temperature band, the preliminary output value of the heater unit 120 can be corrected so that the internal temperature of the process tube 110 does not drop below a specific temperature, and it can be corrected by reinforcing to be higher than the preliminary output value of the heater unit 120.

[0053] At this time, the output value correction unit 143 can correct by multiplying a decay coefficient, which is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature range in the decay temperature range, to the preliminary output value of the heater unit 120, and can correct by adding a reinforcement value, which is proportional to the temperature drop width with respect to the lower limit of the normal control temperature range in the reinforcement temperature range, to the preliminary output value of the heater unit 120. In the decay temperature range, the output value correction unit 143 can perform decay correction on the preliminary output value of the heater unit 120 so that the external temperature of the process tube 110 does not become over-temperature due to the high output of the heater unit 120. The output value correction unit 143 can multiply a decay coefficient, which is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature range, to the preliminary output value of the heater unit 120 to correct the preliminary output value of the heater unit 120 to be low. For example, if the external temperature of the process tube 110 is higher than the (upper limit of) the normal control temperature range, the output value correction unit 143 can correct the preliminary output value of the heater unit 120 so that the (final) output value of the heater unit 120 gradually becomes lower. At the lower limit of the decay temperature range, which is the boundary with the normal control temperature range (upper limit), 1 can be multiplied as the decay coefficient to the preliminary output value of the heater unit 120. At the upper limit of the decay temperature range, 0 can be multiplied as the decay coefficient to the preliminary output value of the heater unit 120. That is, as the temperature difference between the (upper limit of) the normal control temperature range and the external temperature of the process tube 110 becomes larger between the lower limit and the upper limit of the decay temperature range, a decay coefficient, which gradually becomes smaller in the range of 0 to 1 in inverse proportion, can be multiplied. At the intermediate temperature between the lower limit and the upper limit of the decay temperature range, 0.5 can be multiplied as the decay coefficient to the preliminary output value of the heater unit 120.

[0054] In the reinforcement temperature range, the output value correction unit 143 can reinforce and correct the preliminary output value of the heater unit 120 so that the internal temperature of the process tube 110 does not drop below a specific temperature. The output value correction unit 143 can add (or sum) a reinforcement value proportional to the temperature rise width with respect to the lower limit of the normal control temperature range to the preliminary output value of the heater unit 120 to correct the preliminary output value of the heater unit 120 to a higher value. For example, the output value correction unit 143 can correct the preliminary output value of the heater unit 120 so that the (final) output value of the heater unit 120 gradually increases as the external temperature of the process tube 110 becomes lower than the (lower limit of) the normal control temperature range. At the upper limit of the reinforcement temperature range, which is the boundary with the normal control temperature range (lower limit), 0% of the preliminary output value of the heater unit 120 can be added (or summed) as the reinforcement value to the preliminary output value of the heater unit 120. At the lower limit of the reinforcement temperature range, 50 to 100% (for example, 50%) of the preliminary output value of the heater unit 120 can be added as the reinforcement value to the preliminary output value of the heater unit 120. That is, as the temperature difference between the (lower limit of) the normal control temperature range and the external temperature of the process tube 110 increases between the upper and lower limits of the reinforcement temperature range, the reinforcement value that gradually increases in the range of 0 to 50 (~100%) can be added in proportion. At the intermediate temperature between the upper and lower limits of the reinforcement temperature range, 25 (~50)% of the preliminary output value of the heater unit 120 can be summed as the reinforcement value to the preliminary output value of the heater unit 120, halving it according to the 50 to 100% reinforcement value at the lower limit of the reinforcement temperature range.

[0055] On the one hand, the temperature band setting unit can set (or specify) a desired temperature at which it is not desired for the external temperature of the process tube 110 to rise above the upper limit of the attenuation temperature band. The output value correction unit 143 can lower the external temperature of the process tube 110 to the attenuation temperature band so that the (final) output value of the heater unit 120 converges to 0% when it is above the upper limit of the attenuation temperature band. For example, the (final) output value of the heater unit 120 may be 0 or a predetermined constant (a value close to 0) (%).

[0056] And the output value correction unit 143 can limit the preliminary output value of the heater unit 120 calculated by, for example, proportional-integral-derivative (PID) within the attenuation temperature band, so that the (final) output value of the heater unit 120 is within a certain guide. In particular, it is possible to wash whether to make the attenuation level linear or exponential within the attenuation temperature band. Since it converges to 0% when it is above the upper limit of the attenuation temperature band, the external temperature of the process tube 110 will drop again, and actually, it becomes possible to maintain a certain level of output of the heater unit 120. For example, when making the attenuation level linear, the (final) output value of the heater unit 120 is the preliminary output value of the heater unit 120 × (1 - B / A) (where A is the width of the attenuation temperature band (the upper limit - lower limit of the attenuation temperature band), and B is the difference value between the measured external temperature of the process tube 110 and the lower limit of the attenuation temperature band (or the upper limit of the normal control temperature band)).) It can be obtained by a linear attenuation formula, and when making the attenuation level exponential, the (final) output value of the heater unit 120 is the preliminary output value of the heater unit 120 × e -m(1-B / A) (where A and B are the same as in the linear attenuation formula, and m is the exponential decay gain.) It can be obtained by an exponential decay formula.

[0057] If the attenuation temperature band is too narrow, the output of the heater unit 120 may change abruptly, resulting in unstable control of the temperature inside the process tube 110, such as frequent on / off of the heater unit 120. Therefore, it is preferably to set the attenuation temperature band to approximately 20 to 50 °C (range). As the control value of the internal temperature of the process tube 110 increases, the attenuation temperature band also moves (or rises) upward as a whole, and the temperature increase process can be clearly performed.

[0058] In the normal control temperature band between the attenuation temperature band and the reinforcement temperature band, the preliminary output value of the heater unit 120 can be directly used as the (final) output value of the heater unit 120, similar to the control only by the internal temperature of the process tube 110 without correction by the output value correction unit 143. In such a case, it will operate in exactly the same manner as when controlling only by the internal temperature of the process tube 110. That is, the (final) output value of the heater unit 120 may be the preliminary output value of the heater unit 120, or may be the same value as the preliminary output value of the heater unit 120.

[0059] And the reinforcement temperature range is a case where the external temperature of the process tube 110 drops further than the error range of the set temperature (or the normal control temperature range), and it may be a case where the process temperature is normally reduced from the process temperature to the standby temperature after the processing step. The output value correction unit 143 can reinforce the output of the heater unit 120 according to the level at which the external temperature of the process tube 110 has dropped when the external temperature of the process tube 110 is within the reinforcement temperature range, thereby preventing the drop of the external temperature of the process tube 110. Such a reinforcement temperature range can be set independently of the attenuation temperature range and may not be used. For example, the (final) output value of the heater unit 120 can be obtained by the formula of the preliminary output value of the heater unit 120 + K*D / C (where C is the width of the reinforcement temperature range (the upper limit - lower limit of the reinforcement temperature range), D is the difference value between the upper limit of the reinforcement temperature range (or the lower limit of the normal control temperature range) and the measured external temperature of the process tube 110, and K is the reinforcement gain).

[0060] When using the reinforcement temperature range, even if proportional-integral-derivative (PID) control is not performed through the reinforcement temperature range, it is possible to prevent the external temperature of the process tube 110 from dropping, and the internal temperature of the process tube 110 is maintained at a certain temperature or higher in any case. Even in the case of an operation error such as a parameter leak of an operator (or worker) who operates the equipment (i.e., the substrate processing apparatus), it is possible to prevent the internal temperature of the process tube 110 from dropping below a specific temperature.

[0061] Further, when the external temperature of the process tube 110 is lower than the reinforcement temperature range, the output value correction unit 143 can output the (final) output value of the heater unit 120 that is the highest and to be used in the reinforcement temperature range, so as to reinforce the external temperature of the process tube 110. At this time, in order to prevent over-temperature due to high output, the (final) output value of the heater unit 120 that is the highest and to be used in the reinforcement temperature range (or the (final) output value of the heater unit at the lower limit of the reinforcement temperature range) can be set and used. For example, the (final) output value of the heater unit 120 can be obtained by the formula of the preliminary output value of the heater unit 120 + K (where K is the reinforcement gain).

[0062] When the output of the heater unit 120 is controlled only by the internal temperature of the process tube 110, it is impossible to prevent over-temperature and excessive drop of the external temperature of the process tube 110. Due to the (large) difference between the set temperature and the measured internal temperature of the process tube 110 in the attenuation temperature range and the reinforcement temperature range, a (rapidly) high or low output of the heater unit 120 occurs, so that the external temperature of the process tube 110 will rise rapidly, and there will be a delay in the rise of the internal temperature of the process tube 110, resulting in a problem that the difference between the external temperature and the internal temperature of the process tube 110 becomes large.

[0063] In order to prevent overheating and excessive drop in the external temperature of the process tube 110, cascade dual-loop control has conventionally been used. However, in the case of cascade dual-loop control, calculations using the measured external temperature of the process tube 110 are included in the control loop (inner) even in the normal control temperature range, making it difficult to perform accurate temperature control and taking a very long time to determine (or set) the appropriate output (parameter) of the heater unit 120. Further, in the cascade dual-loop control, after performing a primary proportional-integral-derivative (PID) calculation using the internal temperature of the process tube 110, a secondary proportional-integral-derivative (PID) calculation using the external temperature of the process tube 110 must always be performed on the calculated value. This not only complicates the determination (or calculation) of the output of the heater unit 120 but also requires a very long time.

[0064] Furthermore, in the cascade double-loop control, if the value calculated in the primary proportional-integral-derivative (PID) operation fluctuates greatly, the secondary proportional-integral-derivative (PID) operation performed according to the subsequent procedure will also fluctuate greatly. As a result, the parameters must be adjusted to slow down the control and / or select a narrow reaction width. The change range with respect to the external temperature of the process tube 110 must be preset (Setting) to determine the temperature range (or band) within which the external temperature of the process tube 110 can exist. Thereafter, the calculated value received must be matched to the output again. Therefore, not only does it take a very long time to find the appropriate (final) output value of the heater unit 120 by the trial-and-error method, but these values must be determined based on the experience of skilled system experts and thermal experts. Also, even if the appropriate (final) output value of the heater unit 120 is determined through the complex process as described above, due to the characteristic of double-loop control, even if the internal temperature of the process tube 110 is measured (or read), the required amount of heat cannot be output. Since it is matched only by the external temperature of the process tube 110, the required heat cannot be output immediately. As a result, it is not possible to perform temperature control with the same accuracy as controlling the output of the heater unit 120 only by the internal temperature of the process tube 110 in the normal control temperature range.

[0065] However, the substrate processing apparatus 100 according to the present invention determines whether the measured external temperature of the process tube 110 corresponds to either the normal control temperature range or the correction temperature range via the external temperature range determination unit, and performs attenuation and / or reinforcement correction, thereby enabling accurate temperature control in the normal control temperature range, and suppressing the maximum and / or minimum change widths of the external temperature of the process tube 110, and enabling the external temperature of the process tube 110 to exist within a certain range in the case of a rapid temperature change. Through this, it is possible to control the internal temperature of the process tube 110 that suppresses rapid thermal changes, and it is possible to achieve high-difficulty temperature control for processes sensitive to particles inside the process tube 110.

[0066] The direct object of temperature increase of the heater unit 120 is the circular dome-shaped process tube 110, and there may be a considerable delay in heat transfer until the internal temperature of the process tube 110 rises. When increasing the temperature from the standby temperature (for example, 300 to 500 °C) to the process temperature (for example, 550 to 710 °C), the temperature increase rate per minute will be determined by the operator's empirical decision-making process, and usually, a temperature increase rate within 5 to 30 °C / min will be selected.

[0067] Since the required time for the entire process is also determined according to such a temperature increase rate, although the highest possible temperature increase rate is selected, it must be possible to perform a plurality of continuous film formation processes. This is mainly expected to operate without stopping for 24 hours a day, 365 days a year.

[0068] However, if a speed that is excessively high is selected, as a result, if a temperature difference of 100 to 200 °C level occurs between the internal temperature and the external temperature of the process tube 110, repeated temperature operation may cause fine cracks (Micro-crack) on the surface of the quartz material process tube 110, or may promote the detachment of the by-product film remaining on the inner side (or inner surface) of the process tube 110 due to the film formation process performed in advance. Due to such an undesired effect, when proceeding with a new process, not only is there a risk of increasing the particles on the substrate 10, but there is also concern that the life of the quartz material process tube 110 may be shortened. This can be a major problem especially when growing insulating films such as silicon-oxide film and silicon-nitride film.

[0069] Analyzing the temperature increase process in detail, the largest output will occur immediately after the temperature increase process (Step) of increasing the temperature from the standby temperature to the process temperature. This is because, in order for the heater unit 120, which has reached the normal state of the standby temperature and is maintaining the temperature at a very low power, to increase the internal temperature of the process tube 110 to the desired speed, a large heat supply is applied within a short time. In such a case, the gap between the external temperature and the internal temperature of the process tube 110 becomes the largest. However, in the present invention, the control of the temperature at this vulnerable moment can be made softer.

[0070] At this time, the heater unit 120 heats the process tube 110 and maintains it at a standby temperature (or a preparation temperature), and after raising the temperature from the standby temperature to the process temperature, it can maintain the process temperature during the processing step. The normal control temperature range and the correction temperature range may have different temperature ranges for each of the standby temperature section, the temperature rising section, and the process temperature section. The heater unit 120 can heat the process tube 110 and can heat the process tube 110 by dividing the section (or time) into a standby temperature section, a temperature rising section, and a process temperature section. For example, the heater unit 120 maintains the internal temperature of the process tube 110 at the standby temperature, and after raising the temperature from the standby temperature to the process temperature, it can maintain the process temperature during the processing step. The internal temperature of the process tube 110 can be raised from the standby temperature of 300 to 500 °C to the process temperature of 550 to 710 °C, and the internal temperature of the process tube 110 can be raised at a temperature rising rate within 5 to 30 °C per minute.

[0071] Here, the normal control temperature range and the correction temperature range may have different temperature ranges for each of the standby temperature section, the temperature rising section, and the process temperature section. Due to the difference in the set temperature (or the desired internal temperature of the process tube) for each section, the normal control temperature range (the temperature range) which is a temperature range of a predetermined range above and below the set temperature may be different. Due to the difference in the normal control temperature range, the correction temperature range (the temperature range) deviating from the normal control temperature range may also be different. Through this, in all of the standby temperature section, the temperature rising section, and the process temperature section, the gap between the internal temperature of the process tube 110 and the external temperature of the process tube 110 is not large, and the internal temperature of the process tube 110 can be gently controlled (or adjusted).

[0072] On the other hand, the substrate processing apparatus 100 of the present invention may further include an upper end temperature measurement unit 133 that measures the temperature of the upper end portion of the process tube 110. The upper end temperature measurement unit 133 is disposed at least partially between the upper end of the process tube 110 and the inner surface of the upper end of the heater unit 120, and can measure the temperature of the upper end portion of the process tube 110 and the temperature of the space between the inner surface of the upper end of the heater unit 120 and the upper end of the process tube 110. Here, the upper end temperature measurement unit 133 can monitor the heat generation temperature of the upper end portion of the process tube 110 by the heating element of the heater unit 120 by measuring (or reading) the temperature of the upper end portion of the process tube 110, and can play an important role as a reference temperature when the heater unit 120 reaches a thermally stable state, and can also be utilized as feedback temperature information regarding the heat transfer state during temperature rise. For example, similar to the external temperature measurement unit 132, the upper end temperature measurement unit 133 may include a rod-shaped spike thermocouple (TC), and can be inserted from the outside (or upper part) of the upper end of the heater unit 120, and one end thereof can be disposed in the space between the upper end of the process tube 110 and the inner surface of the upper end of the heater unit 120 (for example, within a distance of 5 to 20 mm from the upper end of the process tube), and can measure the temperature of the space between the upper end of the process tube 110 and the inner surface of the upper end of the heater unit 120 (that is, the temperature of the upper end portion of the process tube).

[0073] Further, the substrate processing apparatus 100 of the present invention may further include an over-temperature sensing unit (not shown) that senses the over-temperature of the process tube 110. The over-temperature sensing unit (not shown) is mounted at the same height as the external temperature measurement unit 132 and can measure (or read) the temperature at a position substantially the same as that of the external temperature measurement unit 132. The over-temperature of the process tube 110 can be sensed via a circuit separate from the external temperature measurement unit 132, and damage to the process tube 110 caused by the over-temperature of the process tube 110 can be prevented. For example, an over-temperature sensing sensor can be used as the over-temperature sensing unit (not shown). When the temperature of the over-temperature sensing sensor becomes equal to or higher than a threshold temperature (or a set temperature), the output (or the calorific value) of the heater unit 120 can be decreased or turned off.

[0074] FIG. 4 is a flowchart showing a substrate processing method according to another embodiment of the present invention.

[0075] Referring to FIG. 4, the substrate processing method according to another embodiment of the present invention will be described in detail. Matters overlapping with those described above regarding the substrate processing apparatus according to an embodiment of the present invention will be omitted.

[0076] The substrate processing method according to another embodiment of the present invention may include a process (S100) of heating the process tube by a heater unit disposed outside the process tube, a process (S200) of measuring the internal temperature of the process tube using an internal temperature measurement unit, a process (S300) of measuring the external temperature of the process tube using an external temperature measurement unit, and a process (S400) of controlling the output of the heater unit by utilizing the measured internal temperature and external temperature of the process tube.

[0077] First, the process tube is heated by a heater unit disposed outside the process tube (S100). The heater unit can be disposed outside the process tube to heat the process tube and transfer (or provide) thermal energy to the process tube. For example, the heater unit may include a plurality of heaters arranged to wrap the process tube at different heights so as to selectively heat regions of the process space in the process tube at different heights, thereby heating the process space.

[0078] Next, the internal temperature of the process tube is measured using an internal temperature measurement unit (S200). The internal temperature measurement unit can be disposed inside the process tube and measure the internal temperature of the process tube (i.e., the temperature of the process space). For example, the internal temperature measurement unit may be rod-shaped and arranged to extend along the inner wall of the process tube extending in the vertical direction, so as to measure a temperature profile thermocouple (TC) capable of measuring the internal temperature of the process tube for different height regions. The lower part can be supported by a flange that supports the process tube and can also be connected to the outside through the flange.

[0079] Then, the external temperature of the process tube is measured using an external temperature measurement unit (S300). The external temperature measurement unit can be disposed at least partially between the process tube and the heater unit, and can measure the external temperature of the process tube within the heater unit (i.e., the temperature of the space between the heater unit and the process tube). Here, by measuring (or reading) the external temperature of the process tube, the external temperature measurement unit can monitor the heating temperature of the heating element (such as the plurality of heaters) of the heater unit, and can play an important role as a reference temperature when the heater unit reaches a thermally stable state, and can be utilized as feedback temperature information regarding the heat transfer state during temperature rise. For example, the external temperature measurement unit may include a rod-shaped spike thermocouple (TC), which can be inserted from the outside of the heater unit and one end thereof can be disposed in the space between the process tube and the heater unit (for example, around the process tube or at a distance within 5 to 20 mm from the process tube), and can measure the temperature of the space between the process tube and the heater unit (or around the process tube) (i.e., the external temperature of the process tube).

[0080] Thereafter, the output of the heater unit is controlled (S400) by utilizing the measured internal temperature and external temperature of the process tube. The output of the heater unit can be controlled (or adjusted) by utilizing the measured internal temperature and external temperature of the process tube via the control unit. The measured internal temperature of the process tube can be utilized (or used) to calculate a preliminary output value of the heater unit for quickly adjusting the internal temperature of the process tube to a target temperature (or set temperature). The measured external temperature of the process tube can be utilized to determine (or judge) whether to correct the preliminary output value of the heater unit and / or the correction ratio of the preliminary output value of the heater unit. Based on the determination of whether to correct the preliminary output value of the heater unit using the measured external temperature of the process tube, the output of the heater unit can be controlled by directly using the preliminary output value of the heater unit as the output of the heater unit or by correcting the preliminary output value of the heater unit and using it as the output of the heater unit.

[0081] Here, the process of controlling the output of the heater unit (S400) may include a process of calculating a preliminary output value of the heater unit by utilizing the measured internal temperature of the process tube (S410) and a process of determining whether to correct the preliminary output value of the heater unit based on the measured external temperature of the process tube (S420).

[0082] The preliminary output value of the heater unit can be calculated by utilizing the measured internal temperature of the process tube (S410). The preliminary output value of the heater unit can be calculated (or computed) by utilizing the measured internal temperature of the process tube via a preliminary output value calculation unit, and the preliminary output value of the heater unit for adjusting the internal temperature of the process tube to the target temperature can be calculated. By calculating only using the measured internal temperature of the process tube, the preliminary output value of the heater unit can be quickly calculated, and the output of the heater unit can be calculated (or determined) at high speed by single-loop calculation. Further, the measured internal temperature of the process tube can substitute for the temperature closest to the substrate, and by controlling the output of the heater unit using the preliminary output value of the heater unit calculated (or computed) using this, an accurate process temperature can be provided to the substrate, and the process film quality can be made uniform.

[0083] At this time, the process (S410) of calculating the preliminary output value of the heater unit may include a process (S411) of performing proportional-integral-derivative (PID) calculation by utilizing the measured internal temperature of the process tube.

[0084] Proportional-integral-derivative (PID) calculation can be performed by utilizing the measured internal temperature of the process tube (S411). The preliminary output value calculation unit can perform proportional-integral-derivative (PID) calculation so that the measured internal temperature of the process tube matches the target temperature by utilizing the measured internal temperature of the process tube. The control unit can perform proportional-integral-derivative (PID) control using the preliminary output value of the heater unit that has performed proportional-integral-derivative (PID) calculation, and the output of the heater unit can be adjusted according to the control of the control unit.

[0085] Then, it is possible to determine whether to correct the preliminary output value of the heater unit based on the measured external temperature of the process tube (S420). Through the correction determination unit, it is possible to determine whether to correct the preliminary output value of the heater unit based on the measured external temperature of the process tube. Through this, it is possible to ensure that the output of the heater unit does not exceed the maximum value, and it is possible to prevent the internal temperature of the process tube from dropping below a specific temperature.

[0086] The process of controlling the output of the heater unit (S400) may further include a process (S430) of correcting the preliminary output value of the heater unit when it is determined to correct the preliminary output value of the heater unit.

[0087] When it is determined to correct the preliminary output value of the heater unit, the preliminary output value of the heater unit can be corrected (S430). Through the output value correction unit, the preliminary output value of the heater unit can be corrected based on the determination of the correction determination unit. When it is determined to correct the preliminary output value of the heater unit, the preliminary output value of the heater unit can be corrected. Through this, the output value correction unit can obtain (or calculate) the (final) output value of the heater unit, and can deliver the output signal according to the (final) output value of the heater unit to the heater unit, thereby enabling the output of the heater unit to be controllable.

[0088] The substrate processing method according to the present invention may further include a process (S350) of setting a normal control temperature range in which the preliminary output value of the heater unit is used without correction, and a process (S360) of setting a correction temperature range in which the preliminary output value of the heater unit is corrected and used.

[0089] A normal control temperature band that uses the preliminary output value of the heater unit without correction can be set (S350). The temperature band setting unit can set a normal control temperature band that uses the preliminary output value of the heater unit without correction. Here, in the normal control temperature band, the preliminary output value of the heater unit can be used as the output of the heater unit without correction. For example, the normal control temperature band may be a temperature band that is not excessively high and not excessively low, and may be a temperature band within a predetermined range (or error range) above and below the set temperature (or the target temperature) including the set temperature by time (or by time point), or may be a temperature (range) in a thermally stable state.

[0090] In addition, a correction temperature band that corrects and uses the preliminary output value of the heater unit can be set (S360). The temperature band setting unit can also set a correction temperature band that corrects and uses the preliminary output value of the heater unit. Here, in the correction temperature band, the preliminary output value of the heater unit can be corrected and used as the output of the heater unit (the corrected output value of the heater unit). For example, the correction temperature band may be a temperature band that is excessively hard or excessively low, and may be a temperature band that is higher or lower outside a predetermined range of temperature bands above and below the set temperature, or may be a temperature (range) in a thermally unstable state.

[0091] And the process of determining whether to correct the preliminary output value of the heater unit (S420) may include a process of determining which of the normal control temperature band and the correction temperature band the measured external temperature of the process tube corresponds to (S421).

[0092] It is possible to determine which temperature range of the normal control temperature range and the correction temperature range the measured external temperature of the process tube corresponds to (S421). Through the external temperature range determination unit, it is possible to determine which temperature range of the normal control temperature range and the correction temperature range the measured external temperature of the process tube corresponds to. When the measured external temperature of the process tube corresponds to the normal control temperature range, it is possible to determine (or judge) non-correction of the preliminary output value of the heater unit. When the measured external temperature of the process tube corresponds to the correction temperature range, it is possible to determine (or judge) correction of the preliminary output value of the heater unit.

[0093] The process (S360) of setting the correction temperature range may include a process (S361) of setting a decay temperature range in a temperature range higher than the normal control temperature range and a process (S362) of setting a reinforcement temperature range in a temperature range lower than the normal control temperature range.

[0094] It is possible to set a decay temperature range in a temperature range higher than the normal control temperature range (S361). The temperature range setting unit can set a decay temperature range in a temperature range higher than the normal control temperature range while setting the correction temperature range. At this time, the decay temperature range may be a temperature range higher than the normal control temperature range. When the measured external temperature of the process tube corresponds to the decay temperature range, it is possible to correct the preliminary output value of the heater unit so that the external temperature of the process tube does not become over-temperature due to the high output of the heater unit, and it is possible to correct it by decaying to be lower than the preliminary output value of the heater unit.

[0095] And a reinforcement temperature range in a lower temperature range than the normal control temperature range can be set (S362). The temperature range setting unit can also set a reinforcement temperature range in a lower temperature range than the normal control temperature range while setting the correction temperature range. At this time, the reinforcement temperature range may be a lower temperature range than the normal control temperature range. When the measured external temperature of the process tube corresponds to the reinforcement temperature range, the preliminary output value of the heater unit can be corrected so that the internal temperature of the process tube does not drop below a specific temperature, and it can be reinforced and corrected to be higher than the preliminary output value of the heater unit.

[0096] Here, the process (S430) of correcting the preliminary output value of the heater unit may include a process (S431) of multiplying the preliminary output value of the heater unit by a decay coefficient that is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature range when the measured external temperature of the process tube corresponds to the decay temperature range, and a process (S432) of adding a reinforcement value proportional to the temperature drop width with respect to the lower limit of the normal control temperature range to the preliminary output value of the heater unit for correction when the measured external temperature of the process tube corresponds to the reinforcement temperature range.

[0097] When the measured external temperature of the process tube corresponds to the attenuation temperature band, a correction can be made by multiplying a decay coefficient, which is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature band, by the preliminary output value of the heater unit (S431). The output value correction unit can correct by multiplying the preliminary output value of the heater unit by a decay coefficient that is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature band in the attenuation temperature band. When the measured external temperature of the process tube corresponds to the attenuation temperature band, the output value correction unit can perform attenuation correction on the preliminary output value of the heater unit so that the external temperature of the process tube does not become over-temperature due to the high output of the heater unit. The output value correction unit can multiply the preliminary output value of the heater unit by a decay coefficient that is inversely proportional to the temperature rise width with respect to the upper limit of the normal control temperature band to correct the preliminary output value of the heater unit to be lower. For example, the output value correction unit can correct the preliminary output value of the heater unit so that the (final) output value of the heater unit gradually decreases as the external temperature of the process tube becomes higher than the (upper limit of the) normal control temperature band. At the lower limit of the attenuation temperature band, which is the boundary with the (upper limit of the) normal control temperature band, 1 can be multiplied as the decay coefficient by the preliminary output value of the heater unit. At the upper limit of the attenuation temperature band, 0 can be multiplied as the decay coefficient by the preliminary output value of the heater unit. That is, as the temperature difference between the (upper limit of the) normal control temperature band and the external temperature of the process tube increases between the lower limit and the upper limit of the attenuation temperature band, a decay coefficient that gradually decreases in the range of 0 to 1 in inverse proportion can be multiplied.

[0098] When the measured external temperature of the process tube corresponds to the reinforcement temperature range, a reinforcement value proportional to the temperature drop width with respect to the lower limit of the normal control temperature range can be added to and corrected with the preliminary output value of the heater unit (S432). The output value correction unit can add and correct a reinforcement value proportional to the temperature drop width with respect to the lower limit of the normal control temperature range in the reinforcement temperature range to the preliminary output value of the heater unit. When the measured external temperature of the process tube corresponds to the reinforcement temperature range, the output value correction unit can reinforce and correct the preliminary output value of the heater unit so that the internal temperature of the process tube does not drop below a specific temperature. The output value correction unit can add (or sum) a reinforcement value proportional to the temperature rise width with respect to the lower limit of the normal control temperature range to the preliminary output value of the heater unit to correct the preliminary output value of the heater unit to a higher value. For example, the output value correction unit can correct the preliminary output value of the heater unit so that the (final) output value of the heater unit gradually increases as the external temperature of the process tube becomes lower than the (lower limit of the) normal control temperature range. At the upper limit of the reinforcement temperature range, which is the boundary with the normal control temperature range (lower limit), 0% of the preliminary output value of the heater unit can be added (or summed) as the reinforcement value to the preliminary output value of the heater unit. At the lower limit of the reinforcement temperature range, 50 - 100% (for example, 50%) of the preliminary output value of the heater unit can be added as the reinforcement value to the preliminary output value of the heater unit. That is, as the temperature difference between the (lower limit of the) normal control temperature range and the external temperature of the process tube increases between the upper and lower limits of the reinforcement temperature range, a reinforcement value that gradually increases in the range of 0 - 50 (~100)% can be added proportionally.

[0099] The process (S100) of heating the process tube may include a process (S110) of heating and holding the process tube at a standby temperature, a process (S120) of raising the temperature from the standby temperature to a process temperature, and a process (S130) of holding the process temperature during the processing step for the substrate.

[0100] The process tube can be heated to and held at a standby temperature (or a preparation temperature) (S110). The heater unit can heat the process tube and hold the internal temperature of the process tube at the standby temperature by heating the process tube.

[0101] Thereafter, the temperature can be raised from the standby temperature to a process temperature (S120). The heater unit can heat the process tube to raise the internal temperature of the process tube from the standby temperature to the process temperature. For example, the internal temperature of the process tube can be raised from the standby temperature of 300 to 500 °C to the process temperature of 550 to 710 °C, and the internal temperature of the process tube can be raised at a temperature rising rate within 5 to 30 °C per minute.

[0102] Then, the process temperature can be held during the processing step for the substrate (S130). The heater unit can heat the process tube to hold the internal temperature of the process tube at the process temperature during the processing step for the substrate.

[0103] At this time, in the normal control temperature range and the correction temperature range, the temperature ranges may be different for each process in the process (S110) of heating and holding at the standby temperature, the process (S120) of raising the temperature to the process temperature, and the process (S130) of holding the process temperature. In the process (S110) of heating and holding at the standby temperature, the process (S120) of raising the temperature to the process temperature, and the process (S130) of holding the process temperature, the temperature ranges may be different for each process. By having different set temperatures (or the internal temperatures of the desired process tubes) for each process, the temperature range of the normal control temperature range, which is a temperature range within a predetermined range above and below the set temperature, may be different. Due to the difference in the normal control temperature range, the temperature range of the correction temperature range that deviates from the normal control temperature range may also be different. Through this, in all of the process (S110) of heating and holding at the standby temperature, the process (S120) of raising the temperature to the process temperature, and the process (S130) of holding the process temperature, the difference between the internal temperature and the external temperature of the process tube is not large compared to the external temperature of the process tube, and the internal temperature of the process tube can be gently controlled (or adjusted).

[0104] When each component of the substrate processing apparatus is made of a material having a different coefficient of thermal expansion, a large difference between the internal temperature and the external temperature of the process tube increases the aging rate of each component, and as a result, shortens the life of each component. However, the substrate processing method according to the present invention can also prevent the difference between the internal temperature and the external temperature of the process tube from being maintained at a level where the aging rate does not increase and the life of each component from being shortened due to a high aging rate.

[0105] Thus, in the present invention, by calculating the preliminary output value of the heater unit by utilizing the measured internal temperature of the process tube, the output of the heater unit can be determined at high speed by single-loop calculation. Further, based on the measured external temperature of the process tube, it is determined whether or not to correct the preliminary output value of the heater unit. When it is determined that correction is necessary, by correcting the preliminary output value of the heater unit, while preventing a sudden output of the heater unit, the difference between the internal temperature and the external temperature of the process tube can be maintained within a certain level. As a result, while the output of the heater unit can be determined at high speed, it is possible to prevent the peeling of the by-product film in the process tube and the generation of particles caused by the increase in the difference between the internal temperature and the external temperature of the process tube due to the sudden output of the heater unit. That is, the single-loop calculation utilizing the internal temperature of the process tube can achieve the same effect as the output control of the heater unit using cascade double-loop calculation. Further, in the present invention, it is also possible to prevent the difference between the internal temperature and the external temperature of the process tube from being maintained at a level where the aging rate does not increase, and the life of each component is shortened due to a high aging rate.

[0106] As described above, the preferred embodiments of the present invention have been illustrated and described. However, the present invention is not limited to the above-described embodiments at all, and various modifications can be made without departing from the gist of the present invention claimed in the claims, and it should be understood that other equivalent embodiments can be adopted by those having ordinary knowledge in the field to which the present invention belongs. Therefore, the technical protection scope of the present invention should be determined by the appended claims.

Explanation of Reference Numerals

[0107] 10: Substrate 100: Substrate processing apparatus 110: Process tube 120: Heater unit 131: Internal temperature measurement unit 132: External temperature measurement unit 133: Upper end temperature measurement unit 140: Control Unit 141: Preliminary Output Value Calculation Unit 142: Correction Judgment Unit 143: Output Value Correction Unit

Claims

1. a process tube providing a process space in which a process is performed on a plurality of substrates stacked in multiple stages; a heater unit disposed outside the process tube and configured to heat the process tube; an internal temperature measuring unit disposed inside the process tube for measuring an internal temperature of the process tube; an external temperature measuring unit disposed at least partially between the process tube and the heater unit for measuring an external temperature of the process tube; a control unit for controlling an output of the heater unit by using the internal temperature of the process tube measured by the internal temperature measuring unit and the external temperature of the process tube measured by the external temperature measuring unit; Equipped with The control unit is a preliminary output value calculation unit that calculates a preliminary output value of the heater unit by using the measured internal temperature of the process tube; a correction determination unit that determines whether or not a preliminary output value of the heater unit is to be corrected based on the measured external temperature of the process tube; The substrate processing apparatus includes:

2. The substrate processing apparatus according to claim 1 , wherein the control unit further comprises an output value correction unit that corrects the preliminary output value of the heater unit based on a determination by the correction determination unit.

3. The correction determination unit a temperature band setting unit that sets a normal control temperature band in which a preliminary output value of the heater unit is used without being corrected and a correction temperature band in which a preliminary output value of the heater unit is corrected and used; an external temperature band determining unit for determining whether the measured external temperature of the process tube corresponds to the normal control temperature band or the correction temperature band; The substrate processing apparatus of claim 2 .

4. The correction temperature band is An attenuation temperature band that is a higher temperature band than the normal control temperature band; A reinforcement temperature zone that is a lower temperature zone than the normal control temperature zone; Including, The output value correction unit a damping coefficient inversely proportional to a temperature rise in the damping temperature band relative to an upper limit of the normal control temperature band is multiplied by the preliminary output value of the heater unit to correct the temperature rise in the damping temperature band; 4. The substrate processing apparatus according to claim 3, wherein a compensation value proportional to a temperature drop in the compensation temperature band from a lower limit of the normal control temperature band is added to the preliminary output value of the heater unit for compensation.

5. the heater unit heats the process tube to a standby temperature and maintains the process temperature during the treatment process after increasing the temperature from the standby temperature to a process temperature; The substrate processing apparatus of claim 3 , wherein the normal control temperature band and the correction temperature band have different temperature ranges for each of a standby temperature zone, a heating zone, and a process temperature zone.

6. 2. The substrate processing apparatus of claim 1, wherein the preliminary output value calculation unit performs a proportional-integral-derivative (PID) calculation using the measured internal temperature of the process tube.

7. heating the process tube by a heater disposed outside the process tube; measuring an internal temperature of the process tube using an internal temperature measuring unit; measuring an external temperature of the process tube using an external temperature measuring unit; controlling an output of the heater unit using the measured internal temperature and external temperature of the process tube; Including, The step of controlling the output of the heater unit includes: calculating a preliminary output value of the heater unit using the measured internal temperature of the process tube; determining whether to correct a preliminary output value of the heater unit based on the measured external temperature of the process tube; A method for processing a substrate, comprising:

8. 8. The method of claim 7, wherein the step of controlling the output of the heater unit further comprises the step of correcting a preliminary output value of the heater unit when it is determined that a preliminary output value of the heater unit needs to be corrected.

9. setting a normal control temperature range in which the preliminary output value of the heater unit is not corrected; setting a correction temperature band to be used by correcting a preliminary output value of the heater unit; Further comprising:

9. The substrate processing method of claim 8, wherein the step of determining whether or not to correct the preliminary output value of the heater unit includes a step of determining whether the measured external temperature of the process tube corresponds to the normal control temperature band or the correction temperature band.

10. The step of setting the correction temperature band includes: setting an attenuation temperature band that is higher than the normal control temperature band; setting a reinforcement temperature zone lower than the normal control temperature zone; Including, The step of correcting the preliminary output value of the heater unit includes: correcting the measured external temperature of the process tube by multiplying a damping coefficient, which is inversely proportional to a temperature rise with respect to an upper limit of the normal control temperature band, by a preliminary output value of the heater unit when the measured external temperature of the process tube corresponds to the damping temperature band; when the measured external temperature of the process tube corresponds to the reinforcement temperature range, correcting the auxiliary output value of the heater unit by adding a reinforcement value proportional to a temperature drop width from a lower limit of the normal control temperature range; The method of claim 9 , further comprising:

11. The step of heating the process tube comprises: heating and maintaining the process tube at a standby temperature; increasing the temperature from the standby temperature to a process temperature; maintaining the process temperature between processing steps on the substrate; Including, 10. The method of claim 9, wherein the normal control temperature band and the correction temperature band have different temperature ranges for each of the steps of heating to the standby temperature and maintaining the standby temperature, heating to the process temperature, and maintaining the process temperature.

12. 8. The method of claim 7, wherein the calculating a preliminary output value of the heater unit comprises performing a proportional-integral-derivative (PID) calculation using the measured internal temperature of the process tube.

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