Temperature control system, temperature control method, method for manufacturing semiconductor device, and substrate processing apparatus

Abstract

Provided is a technology capable of suppressing temperature rise of a heating wire of an auxiliary heater and ensuring the service life of the auxiliary heater. A temperature control system is provided with: a first heater which is provided so as to be divided into regions and which heats a processing container in which a substrate is disposed; a second heater that assists heating by the first heater corresponding to a specific region among the regions; a temperature sensor that detects the temperature of the second heater; and a control unit configured to limit the output of the second heater when the temperature detected by the temperature sensor is equal to or higher than a predetermined temperature lower than a target temperature, thereby enabling the temperature in the processing container to reach the target temperature.

Description

Technical Field

[0001] This disclosure relates to a temperature control system, a temperature control method, a method for manufacturing a semiconductor device, and a substrate processing apparatus. Background Technology

[0002] As a step in the manufacturing process of semiconductor devices, a specific process is sometimes performed on the wafer (hereinafter also referred to as the substrate) (see, for example, Patent Documents 1 to 6). These documents describe techniques for controlling the temperature of the processing chamber by using auxiliary heaters that assist in heating specific areas.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2016 / 135876

[0006] Patent Document 2: International Publication No. 2020 / 261466

[0007] Patent Document 3: International Publication No. 2019 / 053807

[0008] Patent Document 4: Japanese Patent Application Publication No. 2016-157923

[0009] Patent Document 5: International Publication No. 2020 / 026445

[0010] Patent Document 6: Japanese Patent Application Publication No. 2020-057796 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] This disclosure provides a technique that can suppress the temperature rise of the heating wire in an auxiliary heater, thereby ensuring the lifespan of the auxiliary heater.

[0013] Methods for solving problems

[0014] According to one aspect of this disclosure, a technology is provided that has:

[0015] The first heater is configured to be divided into regions and heats the processing container in which a substrate is disposed;

[0016] The second heater assists in heating the first heater corresponding to a specific area in each of the regions;

[0017] A temperature sensor detects the temperature of the second heater; and

[0018] The control unit is configured to limit the output of the second heater when the temperature detected by the temperature sensor is above a predetermined temperature lower than the target temperature, thereby enabling the temperature inside the processing container to reach the target temperature.

[0019] Invention Effects

[0020] According to this disclosure, the temperature rise of the heating wire of the auxiliary heater can be suppressed, thus ensuring the lifespan of the auxiliary heater. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a processing furnace of a substrate processing apparatus according to one aspect of the present disclosure.

[0022] Figure 2 This is a front sectional view of the auxiliary heater and its surrounding portion of a substrate processing apparatus according to one embodiment of the present disclosure.

[0023] Figure 3 (A) is a top view of the auxiliary heater of a substrate processing apparatus according to one aspect of this disclosure. Figure 3 (B) is Figure 3 (A) shows a partial longitudinal sectional view of the auxiliary heater.

[0024] Figure 4 This is a schematic structural diagram of the controller in a substrate processing apparatus according to one aspect of the present disclosure, and is a diagram of the control system of the controller represented by a block diagram.

[0025] Figure 5 (A) is a diagram representing a first mode of temperature control performed by the temperature control system of this disclosure. Figure 5 (B) is a diagram representing a second mode of temperature control performed by the temperature control system of this disclosure. Figure 5 (C) is a third-party diagram representing the temperature control performed by the temperature control system of this disclosure.

[0026] Figure 6 This is a block diagram of a temperature control system in a substrate processing apparatus according to one aspect of the present disclosure.

[0027] Figure 7 (A) is a diagram illustrating a substrate processing sequence performed by a substrate processing apparatus according to one aspect of the present disclosure. Figure 7 (B) is a diagram illustrating a substrate processing sequence performed by a substrate processing apparatus according to one aspect of the present disclosure, and is a graph showing the temperature in each step of the substrate processing sequence. Detailed Implementation

[0028] (1) Structure of the substrate processing device

[0029] The following is mainly based on Figures 1-7 One aspect of this disclosure will be described. Furthermore, the accompanying drawings used in the following description are schematic, and the dimensional relationships and scales of the elements shown may not necessarily correspond to reality. Additionally, the dimensional relationships and scales of elements may not be consistent across multiple drawings. Moreover, substantially identical elements are labeled with the same symbol across multiple drawings, and the element is described in the drawing in which it first appears; its description is omitted in subsequent drawings unless specifically required.

[0030] like Figure 1 As shown, in this embodiment, the substrate processing apparatus 10 is configured as a processing apparatus (batch processing apparatus) for implementing processing steps in the IC manufacturing method. The processing furnace 12 is a heating unit (heating mechanism) and has a heater 14 as a first heater. The heater 14 is cylindrical and mounted vertically.

[0031] Inside the heater 14, a reaction tube 16 constituting a reaction vessel (processing vessel) is arranged concentrically with the heater 14. The reaction tube 16 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape that is closed at the top and open at the bottom. A processing chamber 18 is formed in the hollow part of the reaction tube 16. The processing chamber 18 is configured to accommodate a wafer 2, which serves as a substrate, arranged in a horizontal orientation and in multiple layers in the vertical direction via a crystal boat 20, described later.

[0032] A nozzle 22 is installed inside the processing chamber 18, extending through the lower part of the reaction tube 16. The nozzle 22 is made of a heat-resistant material such as quartz or SiC. A gas supply pipe 24a is connected to the nozzle 22. From upstream of the gas supply pipe 24a, a mass flow controller (MFC) 26a (flow control unit) and a valve 28a (on / off valve) are sequentially installed. A gas supply pipe 24b for supplying inert gas is connected downstream of the gas supply pipe 24a from the valve 28a. From upstream of the gas supply pipe 24b, an MFC 26b and a valve 28b are sequentially installed. The processing gas supply unit, mainly composed of the gas supply pipe 24a, MFC 26a, and valve 28a, constitutes the processing gas supply system. The inert gas supply unit, mainly composed of the gas supply pipe 24b, MFC 26b, and valve 28b, constitutes the inert gas supply system.

[0033] In the annular space between the inner wall of the reaction tube 16 and the wafer 2, a nozzle 22 is positioned to rise upwards from the lower part of the inner wall of the reaction tube 16 along the upward direction of the wafer 2's arrangement. That is, in the region horizontally surrounding the wafer arrangement region of the wafer 2, the nozzle 22 is positioned along the wafer arrangement region. The nozzle 22 is configured as an L-shaped elongated nozzle, with its horizontal portion extending through the lower sidewall of the reaction tube 16 and its vertical portion rising at least from one end of the wafer arrangement region towards the other. Gas supply holes 30 are provided on the side of the nozzle 22. These gas supply holes 30 open towards the center of the reaction tube 16, enabling gas to be supplied to the wafer 2. Multiple gas supply holes 30 are provided from the lower to the upper part of the reaction tube 16, each having the same opening area and the same opening spacing.

[0034] However, the processing furnace 12 of this method is not limited to the above-described method. For example, a metal manifold supporting the reaction tube 16 can be provided below the reaction tube 16, and the nozzle can be configured to penetrate the side wall of the manifold. In this case, an exhaust pipe 120, which will be described later, can also be provided in the manifold. In this case, the exhaust pipe 120 can also be provided in the lower part of the reaction tube 16 instead of the manifold. In this way, the furnace opening of the processing furnace 12 can be made of metal, and nozzles can be installed in this metal furnace opening. Alternatively, multiple nozzles can be provided.

[0035] An exhaust pipe 120 is provided in the reaction tube 16 to discharge the atmosphere from the processing chamber 18. The exhaust pipe 120 is connected to a vacuum pump 36, which is a vacuum exhaust device, via a pressure sensor 32 (pressure detector, pressure detection unit) and an APC (Auto Pressure Controller) valve 34 (pressure regulator, pressure adjustment unit), which detects the pressure in the processing chamber 18. The APC valve 34 can perform vacuum exhaust and stop vacuum exhaust within the processing chamber 18 by opening and closing the valve while the vacuum pump 36 is operating. Furthermore, the APC valve 34 is configured to adjust the pressure within the processing chamber 18 by adjusting the valve opening based on the pressure information detected by the pressure sensor 32 while the vacuum pump 36 is operating. The exhaust system mainly consists of the exhaust pipe 120, the APC valve 34, and the pressure sensor 32. It is also possible to include the vacuum pump 36 in the exhaust system.

[0036] A sealing cover 38, serving as a furnace opening cover, is provided below the reaction tube 16 to airtightly seal the lower opening of the reaction tube 16. The sealing cover 38 is made of a metal such as SUS or stainless steel and is formed in a disc shape. An O-ring 40, serving as a sealing component, is provided on the upper surface of the sealing cover 38 and abuts against the lower end of the reaction tube 16. When a manifold is provided below the reaction tube 16, O-rings 40 are provided between the reaction tube 16 and the manifold, and between the manifold and the sealing cover 38, forming a processing chamber 18 by the reaction tube 16, the manifold, and the sealing cover 38.

[0037] The sealing cap 38 is configured to abut against the lower end of the reaction tube 16 from a vertical downward direction, and is configured to move vertically upward and downward via a crystal boat lift 46, which is vertically disposed outside the reaction tube 16 as a lifting mechanism. That is, the crystal boat lift 46 is configured to move the crystal boat 20 in and out of the processing chamber 18 by raising and lowering the sealing cap 38. In other words, the crystal boat lift 46 is configured as a conveying device (conveyor) for moving the crystal boat 20, i.e., the wafer 2, in and out of the processing chamber 18.

[0038] The crystal boat 20, serving as a substrate support, is configured to support multiple wafers 2, for example, 25 to 200 wafers 2, arranged horizontally and aligned centrally in a vertical direction in multiple layers. The crystal boat 20 is made of a heat-resistant material such as quartz or SiC. At the lower part of the lowest wafer 2 placed on the crystal boat 20, a heat-insulating plate 48, formed in a circular shape with an outer diameter approximately equal to the outer diameter of the wafer 2, is supported horizontally in multiple layers. The heat-insulating plate 48 is formed of a material with low heat capacity and high emissivity, such as quartz, silicon (Si), or SiC. This configuration facilitates the absorption of radiant heat from the auxiliary heater 50 (described later), thereby improving the temperature response of the wafer 2 during temperature recovery and shortening the recovery time. Furthermore, the expression "25 to 200 wafers" in this specification refers to the inclusion of both the lower and upper limits within that range. Therefore, for example, "25 to 200 wafers" means "more than 25 wafers and less than 200 wafers." The same applies to other numerical ranges.

[0039] On the side of the sealing cover 38 opposite to the processing chamber 18, a rotation mechanism 42 is provided to rotate the crystal boat 20. The rotation mechanism 42 has a generally cylindrical housing 56 formed with an open upper end and a closed lower end. The housing 56 is arranged concentrically and fixed to the lower surface of the sealing cover 38. Inside the housing 56, an inner shaft 58 formed into an elongated cylindrical shape is arranged vertically and is fixedly supported by the closed wall of the housing 56. Inside the housing 56, an outer shaft 60 is arranged concentrically. The outer shaft 60 is a cylindrical shape with a diameter larger than the outer diameter of the inner shaft 58 and is formed into a hollow disk shape with a central through hole for the auxiliary heater 50 to be inserted through the upper end of the cylindrical shape. The outer shaft 60 is rotatably supported by a pair of upper and lower inner bearings 62, 64 disposed between the outer shaft 58 and the inner shaft 58, and a pair of upper and lower outer bearings 66, 68 disposed between the outer shaft 56 and the housing 56. The auxiliary heater 50, which will be described in detail later, is inserted vertically inside the inner shaft 58.

[0040] A generally cylindrical rotating shaft 54 ​​is fixed to the upper surface of the outer shaft 60. The lower end of the rotating shaft 54 ​​has an outwardly flanged shape, and a through hole is formed in the center for the auxiliary heater 50 to pass through. A generally cylindrical base 96 is fixed to the upper end of the rotating shaft 54 ​​and the upper surface of the sealing cover 38. The base 96 has an outwardly flanged shape, and a through hole is formed in the center for the auxiliary heater 50 to pass through. The base 96 is formed, for example, from a heat-resistant material such as quartz or SiC.

[0041] A heat insulation retainer 110 is fixed to the upper surface of the sealing cover 38. The heat insulation retainer 110 consists of a disc-shaped upper plate 112, a hollow disc-shaped lower plate 114 having an outer diameter of the same size as the upper plate 112 and an inner diameter larger than that of the base 96, and three retaining posts 116 mounted between the upper plate 112 and the lower plate 114. Below the upper plate 112 is a secondary heater (also called a cover heater) 50, which serves as an auxiliary heating part (also called an auxiliary heating mechanism or auxiliary heater) and a second heater. Below the secondary heater 50 and in retaining grooves formed on the three retaining posts 116, quartz heat insulation elements 108 are arranged at equal intervals.

[0042] The crystal boat 20 is connected above the heat insulation holding part 110 via a support column 99. That is, the upper plate 112 and the disc-shaped crystal boat plate 98 provided at the lower end of the crystal boat 20 are connected by a support column 99 provided on the same axis.

[0043] The heater 14 is configured to be divided into, for example, five control regions U, CU, C, CL, and L from the top to the bottom. The heater 14 is configured to heat each region within the processing container to a target temperature. Additionally, the auxiliary heater 50 is configured to assist in heating specific regions, such as the bottommost region L. In other words, region L is the region where the temperature fluctuation detected by the temperature sensor 52 is the largest, for example, the region where the temperature tends to be the lowest. Therefore, the wafer 2 located at the bottom of the wafer 20, placed in the wafer carrier 20, can be heated to a specified temperature within a predetermined time (performing a heating step). Thus, in addition to the heater 14, heating is also performed by the auxiliary heater 50, thereby enabling the wafer 2 located in a region where the temperature is unlikely to rise (e.g., region L) to be heated to the target temperature without delay. This shortens the heating time (heating step) without prolonging the heating time.

[0044] Here, when the lower wafer 2 of the wafer 2 placed in the wafer boat 20 is located in region CU, the auxiliary heater 50, described later, is configured to be located near the wafer 2 located below the wafer boat 20. That is, the auxiliary heater 50 is preferably located in the region where the wafer 2 is placed and near the lower side of the wafer 2, where the wafer 2 is located below the wafer boat 20. Thus, in addition to the heater 14, the wafer 2 is heated by the auxiliary heater 50, thereby enabling the lowermost wafer 2 of the wafer boat 20 to be heated and heated to a predetermined temperature within a predetermined time (performing a heating step). Here, "lowest" refers to about a few to a dozen wafers 2 counting from the bottommost edge of the wafer 2 held in the wafer boat 20 (from the bottommost wafer 2).

[0045] Thermocouples 302 are installed at positions corresponding to each region on the inner wall of the heater 14. Thermocouples 302 are heater thermocouples that detect the temperature of the heater 14 in each region. Hereinafter, the temperature detected by the thermocouples 302 will be designated as the heater TC detection temperature, or the heater temperature.

[0046] A temperature sensor 52, serving as the first temperature sensor, is installed in the annular space between the inner wall of the reaction tube 16 and the wafer 2. The temperature sensor 52, like the nozzle 22, is L-shaped and is positioned along the inner wall of the reaction tube 16. Thermocouples 303 are installed at positions corresponding to each region of the temperature sensor 52. Thermocouples 303 are cascaded thermocouples that detect the temperature of the processing chamber 18 formed within each region of the reaction tube 16. Hereinafter, the temperature detected by the thermocouples 303 will be referred to as the furnace internal TC detection temperature (furnace temperature).

[0047] In detail, the controller 200, which is described later as the control unit, is configured to adjust the energization of each area in the heater 14 and the energization of the auxiliary heater 50 based on the temperature information detected by the thermocouples 302, 303 and 304 in each area, and control the temperature of the processing chamber 18 (furnace temperature) to the target temperature.

[0048] Next, use Figure 3 (A) and Figure 3 (B) provides details of the auxiliary heater 50 in this embodiment.

[0049] The auxiliary heater 50 has: a vertically extending support portion 82 and a heating portion 84 disposed approximately horizontally relative to the support portion 82.

[0050] The heating element 84 is formed in a generally annular shape with a diameter smaller than the outer diameter of the wafer 2, and is configured to be supported horizontally relative to the upper end of the support portion 82. In other words, the heating element 84 is supported parallel to the wafer 2. A heater heating wire 88 is encapsulated inside the heating element 84. This heater heating wire 88 is a resistive heating wire constituting the resistive heating element 146, which is a heating element formed in a coil shape. The resistive heating element 146 is formed, for example, from an Fe-Cr-Al alloy or molybdenum disilicide. The two ends of the heater heating wire 88 are bent downwards in a vertical direction at the connection between the support portion 82 and the heating element 84 and are introduced into the interior of the support portion 82.

[0051] A protrusion 128 is formed at the upper end of the support portion 82. The protrusion 128 has a cross-sectional area larger than the cross-sectional area below it, i.e., the cross-sectional area of ​​the support portion 82. A heating portion 84 is connected to the upper surface of the protrusion 128. The heating portion 84 is configured as a ring with the upper surface of the protrusion 128 as the starting point and the ending point.

[0052] A temperature sensor 150, serving as a second temperature sensor for detecting the temperature of the auxiliary heater 50, is disposed in the auxiliary heater 50 through the support column 82. The temperature sensor 150 bends horizontally upwards, forming a roughly L-shaped cross-section. The temperature sensor 150 is formed of a tubular component, with a thermocouple 304 disposed at its inner front end. The temperature sensor 150 extends horizontally above the protrusion 128, i.e., at the center of the annular portion 130, and connects to the outer wall of the annular portion 130. The horizontal portion of the temperature sensor 150 is formed parallel to the heating element 84. Furthermore, the horizontal height of the temperature sensor 150 is configured to be the center of the diameter of the annular portion 130 when viewed longitudinally in the auxiliary heater 50. Here, the horizontal height refers to the center of the diameter of the horizontal portion when viewed vertically in the cross-section of the temperature sensor 150. The thermocouple 304 of the temperature sensor 150 is disposed near the outer wall of the annular portion 130 to detect the temperature of the auxiliary heater 50.

[0053] like Figure 4 As shown, the controller 200, which serves as the control unit (control unit), is configured as a computer having a CPU (Central Processing Unit) 212, RAM (Random Access Memory) 214, a storage device 216, and an I / O port 218. The RAM 214, storage device 216, and I / O port 218 are configured to exchange data with the CPU 212 via an internal bus 220. An input / output device 222, such as a touch panel, is connected to the controller 200.

[0054] Storage device 216 is configured such as flash memory or HDD (Hard Disk Drive). Storage device 216 stores, in a readable manner, a control program that controls the operation of the substrate processing apparatus 10, and a process flow describing the substrate processing procedures or conditions described later. The process flow is a combination of processes that enable the controller 200 to execute each step of the substrate processing steps described later to obtain a predetermined result, and functions as a program. Hereinafter, this process flow or control program will also be collectively referred to as a program (program product). In this specification, when the term "program" is used, it refers to a program recorded on a computer-readable storage medium, which may contain only a process flow unit, only a control program unit, or both. RAM 214 is configured as a storage area (working area) for temporarily holding programs or data read by CPU 212.

[0055] I / O port 218 is connected to the aforementioned MFC26a, 26b, valves 28a, 28b, pressure sensor 32, APC valve 34, vacuum pump 36, heater 14, auxiliary heater 50, temperature sensor 52, 150, rotating mechanism 42, crystal boat lift 46, etc.

[0056] CPU 212 is configured to read and execute control programs from storage device 216, and to read process data from storage device 216 based on input commands from input / output device 222. CPU 212 is configured to control the following actions according to the read process data: flow rate adjustment of various gases performed by MFCs 26a and 26b; opening and closing of valves 28a and 28b; opening and closing of APC valve 34 and pressure adjustment based on pressure sensor 32; starting and stopping of vacuum pump 36; temperature adjustment of heater 14 and auxiliary heater 50 based on temperature sensors 52 and 150; rotation and speed adjustment of crystal boat 20 performed by rotating mechanism 42; and lifting and lowering of crystal boat 20 performed by crystal boat lift 46.

[0057] The controller 200 is configured to install the aforementioned program stored in an external storage device (e.g., magnetic tape, floppy disk, hard disk, CD, DVD, USB memory, memory card, etc.) 224 onto a computer. The storage device 216 and the external storage device 224 constitute a computer-readable storage medium on which the program is recorded. Hereinafter, they will also be collectively referred to as storage media. In this specification, when the term "storage media" is used, there may be a case where only the storage device 216 is included, a case where only the external storage device 224 is included, or a case where both are included. Furthermore, the program may be provided to the computer using a communication unit such as the Internet or a dedicated line, without using the external storage device 224.

[0058] (2) Substrate processing process

[0059] Next, using the substrate processing apparatus 10 described above as a step in the semiconductor device manufacturing process, an example of a substrate processing sequence in which a film is formed on the wafer 2 (hereinafter also referred to as film formation processing) and the formed film is annealed (hereinafter also referred to as annealing processing) will be described. Furthermore, in the following description, the operation of each part constituting the substrate processing apparatus 10 is controlled by the controller 200.

[0060] As used in this specification, the term "wafer" sometimes refers to the wafer itself, and sometimes to a laminate of the wafer and a specified layer or film formed on its surface. The term "surface of the wafer" as used in this specification sometimes refers to the surface of the wafer itself, and sometimes to the surface of a specified layer, etc., formed on the wafer. When described in this specification as "forming a specified layer on the wafer," it sometimes means forming the specified layer directly on the surface of the wafer itself, and sometimes it means forming the specified layer on top of layers, etc., formed on the wafer. The use of the term "substrate" in this specification has the same meaning as the use of the term "wafer."

[0061] (Wafer loading and crystal boat loading)

[0062] When multiple wafers 2 are loaded (wafer loading) into the crystal boat 20, the crystal boat 20 is moved (crystal boat loading) into the processing chamber 18 by the crystal boat elevator 46. At this time, the sealing cap 38 is in a state where the lower end of the reaction tube 16 is hermetically sealed (sealed) via the O-ring 40.

[0063] (Pressure and temperature adjustment)

[0064] Vacuum pump 36 performs vacuum venting (pressure reduction venting) to bring the processing chamber 18, i.e., the space where wafer 2 is located, to a specified pressure (vacuum level). At this time, pressure sensor 32 measures the pressure in processing chamber 18 and uses this measured pressure information to provide feedback control to APC valve 34. Vacuum pump 36 remains operational at least until the processing of wafer 2 is completed.

[0065] Additionally, heating is performed by heater 14 and auxiliary heater 50 to bring the temperature of the processing chamber 18 to a predetermined temperature. At this time, feedback control is applied to the energizing of heater 14 based on temperature information detected by temperature sensor 52, ensuring that the processing chamber 18 has a predetermined temperature distribution limited to a specific area. Feedback control is also applied to the energizing of heater 14 based on temperature information detected by temperature sensors 52 and 150 respectively. Furthermore, feedback control can also be applied to the energizing of auxiliary heater 50 based on temperature information detected by temperature sensor 150. Heating of the processing chamber 18 by heater 14 and auxiliary heater 50 continues at least until the processing of wafer 2 is completed. Furthermore, heating by auxiliary heater 50 can be stopped at this time. That is, auxiliary heater 50 and heater 14 are controlled independently; therefore, heating by auxiliary heater 50 can be omitted, and heater 14 can heat the wafer 2 in the processing chamber 18 alone.

[0066] Furthermore, the rotation of the crystal boat 20 and the wafer 2 is initiated by the rotation mechanism 42. The crystal boat 20 is rotated using the rotation mechanism 42, thereby rotating the wafer 2. During this time, the heat shield 108 and the auxiliary heater 50 do not rotate. The rotation of the crystal boat 20 and the wafer 2 by the rotation mechanism 42 continues at least until the processing of the wafer 2 is completed. In this embodiment, a heat shield holding portion 110 containing the heat shield 108 is fixed, but it may also be configured such that the heat shield holding portion 110 containing the heat shield 108 rotates in the same manner as the crystal boat 20 via the rotation mechanism 42.

[0067] (Film-forming treatment)

[0068] When the temperature of the processing chamber 18 stabilizes at the preset processing temperature, raw material gas is supplied to the wafer 2 in the processing chamber 18. Here, the processing temperature in this specification refers to the furnace temperature or the temperature inside the processing container (the temperature of the processing chamber 18).

[0069] Specifically, valve 28a is opened to allow the raw material gas to flow into the gas supply pipe 24a. The flow rate of the raw material gas is adjusted by MFC 26a, and it is supplied to the processing chamber 18 via nozzle 22 and discharged from exhaust pipe 120. At this time, raw material gas is supplied to wafer 2. At the same time, valve 28b can also be opened to allow inert gas to flow into the gas supply pipe 24b. In this case, the flow rate of the inert gas is adjusted by MFC 26b, and it is supplied to the processing chamber 18 together with the raw material gas and discharged from exhaust pipe 120.

[0070] Then, after a predetermined film containing the raw material elements is formed on wafer 2, valve 28a is closed to stop the supply of raw material gas. At this time, with APC valve 34 remaining open, vacuum pump 36 is used to evacuate the processing chamber 18, removing any unreacted or raw material gases remaining in the processing chamber 18 that may contribute to film formation. Then, valve 28b can be opened to supply inert gas to the processing chamber 18. This improves the effectiveness of removing residual gas from the processing chamber 18.

[0071] As described above, this embodiment illustrates an example of forming a membrane solely by supplying a feed gas, but the membrane formation process is not limited to this method. For example, a feed gas and a reactant gas (not shown) can be supplied simultaneously, or the feed gas and reactant gas (not shown) can be supplied cyclically. For example, a container (not shown) for temporarily storing gas can be provided, in which a predetermined amount of feed gas is stored, and the feed gas is supplied to the processing chamber 18 in a single release.

[0072] Furthermore, during the aforementioned film-forming process, the controller 200 can control the energization of the auxiliary heater 50, which will be described later.

[0073] (Heating up)

[0074] After the film formation process is completed, that is, after the specified film is formed on the wafer 2, the wafer 2 in the processing chamber 18 is heated by the heater 14 and the auxiliary heater 50 to an annealing temperature, i.e., a target temperature, which is higher than the processing temperature in the film formation process described above. At this time, the valve 28b is opened, and inert gas is supplied to the processing chamber 18 through the nozzle 22 and discharged from the exhaust pipe 120 to purge the processing chamber 18.

[0075] (Annealing treatment)

[0076] After the temperature of the processing chamber 18 reaches the target temperature and stabilizes, the wafer 2 in the processing chamber 18, i.e. the specified film formed on the wafer 2, is subjected to heat treatment (annealing).

[0077] (Purge and atmospheric pressure recovery)

[0078] After the annealing process is completed, valve 28b is opened, and inert gas is supplied to the processing chamber 18 from the gas supply pipe 24b and discharged from the exhaust pipe 120. The inert gas acts as a purging gas. As a result, the processing chamber 18 is purged, and the gases and reaction byproducts remaining in the processing chamber 18 are removed (purging). Afterward, the atmosphere in the processing chamber 18 is replaced with inert gas (inert gas replacement), and the pressure in the processing chamber 18 is restored to normal atmospheric pressure (atmospheric pressure restoration).

[0079] (Crystal boat unloading and wafer unloading)

[0080] The sealing cover 38 is lowered by the crystal boat lift 46, opening the lower end of the reaction tube 16. Then, the processed wafer 2, supported by the crystal boat 20, is moved from the lower end of the reaction tube 16 to the outside of the reaction tube 16 (crystal boat unloading). The processed wafer 2 is removed from the crystal boat 20 (wafer removal).

[0081] Here, as in the substrate processing step described above, a film formation process follows, sometimes followed by an annealing process within the same processing furnace 12 (or processing chamber 18). If the film formation temperature is, for example, 500~700°C, the target temperature for the annealing process is sometimes 800°C or higher. In such a substrate processing step, it is sometimes necessary to set the target temperature for the annealing process higher than the rated temperature of the auxiliary heater 50. Furthermore, the auxiliary heater 50 uses a heating wire with a smaller diameter than the heater 14; therefore, the controllable temperature (rated temperature) of the auxiliary heater 50 is lower than that of the heater 14. Therefore, if the auxiliary heater 50 is used at a temperature higher than its controllable rated temperature, the temperature of the auxiliary heater 50, i.e., the temperature of the heating wire, rises significantly, accelerating the deterioration of the heating wire in the auxiliary heater 50. As a result, the lifespan of the auxiliary heater 50 is shortened. Additionally, since the auxiliary heater 50 is located below the processing furnace 12 (or processing chamber 18), when the diameter of the heating wire is increased (thickened), design changes to the components around the furnace opening are sometimes required. Furthermore, when the heating wire temperature is suppressed by limiting the maximum output of the heater 14 in order to extend the life of the auxiliary heater 50, the heating time will be longer, resulting in a deterioration in productivity.

[0082] In this disclosure, the controller 200 is configured to select at least one of the temperature control methods shown in the first to third embodiments, or a combination of the temperature control methods shown in the first to third embodiments, to perform temperature control in a temperature range higher than the rated temperature of the auxiliary heater 50. Furthermore, needless to say, the controller 200 is configured to control the heater 14 and the auxiliary heater 50, wherein the heater 14 is configured to be divided into regions and heats the processing container in which the wafer 2 is disposed, and the auxiliary heater 50 assists in heating specific regions. This suppresses the temperature rise of the heating wire of the auxiliary heater 50 and suppresses the degradation of the heating wire of the auxiliary heater 50.

[0083] Furthermore, the controller 200 is configured to be able to appropriately combine the heating performed by both the heater 14 and the auxiliary heater 50, or to use the heater 14 alone, thereby heating the temperature of each region to the target temperature in each step.

[0084] Figure 5 (A) indicates the situation where the output of the auxiliary heater 50 is limited when the temperature of the heating wire of the auxiliary heater 50 is above the specified temperature. Figure 5 (B) indicates the case where the heating rate of the auxiliary heater 50 is reduced when the temperature of the heating wire of the auxiliary heater 50 is above the specified temperature. Figure 5 (C) indicates that the output of the auxiliary heater is delayed until the heating wire temperature of the auxiliary heater 50 reaches above the specified temperature. Figure 5 (A) ~ Figure 5In (C), the thin dashed line represents the furnace temperature in the comparative example, and the thick dashed line represents the heating wire temperature in the comparative example. This indicates that in the heating process of the above-mentioned substrate processing step, in addition to the heater 14, the output of the auxiliary heater 50 is also set to the maximum output, i.e., 100%, for heating. The thin solid lines represent the furnace temperature in the first to third methods, respectively, and the thick solid lines represent the heating wire temperature of the auxiliary heater 50 in the first to third methods, respectively.

[0085] like Figure 5 (A) ~ Figure 5 As shown in (C), when the output of the auxiliary heater 50 is set to 100% in addition to the heater 14, the temperature of the heating wire of the auxiliary heater 50 sometimes temporarily rises above the controllable rated temperature of the auxiliary heater 50 before the furnace temperature reaches the target temperature T1 and becomes constant. For example, when the temperature of region L is raised to the target temperature T1, the controller 200 controls the auxiliary heater 50 to perform at least one of the following first to third modes. Furthermore, at least any two of the following first to third modes can be combined for use.

[0086] (First method)

[0087] In the first approach, before the heating wire temperature detected by temperature sensor 150 reaches a predetermined temperature T2 lower than the target temperature T1, controller 200 keeps the output of auxiliary heater 50 constant or variable, freely controlling it without particular restriction. Then, when the heating wire temperature of auxiliary heater 50 reaches or exceeds the predetermined temperature T2, controller 200 limits the output of auxiliary heater 50. That is, controller 200 controls heater 14 and auxiliary heater 50 such that the temperature inside the processing container (the furnace temperature detected by temperature sensor 52 in each zone) reaches the target temperature T1, and when the temperature of auxiliary heater 50 detected by temperature sensor 150 reaches the predetermined temperature T2, it limits the output of auxiliary heater 50. Specifically, for example, when the temperature exceeds or exceeds the predetermined temperature T2 lower than the target temperature T1, controller 200 controls the output of auxiliary heater 50 to be limited to, for example, 0-30% of the maximum output (100%). Furthermore, the heater temperature in zone L, the output value of auxiliary heater 50, and the heating wire temperature of auxiliary heater 50 have a predetermined relationship, allowing control of the heating wire temperature of auxiliary heater 50. Thus, as Figure 5 As shown in (A), the peak temperature of the heating wire of the auxiliary heater 50 can be lower than the peak temperature of the heating wire of the auxiliary heater 50 in the comparative example, which can suppress the rise in the heating wire temperature of the auxiliary heater 50 and suppress the deterioration of the heating wire of the auxiliary heater 50.

[0088] Here, when the temperature of the auxiliary heater 50, that is, the temperature detected by the temperature sensor 150, is above a specified temperature T2 which is lower than the target temperature T1, the output limit value used to limit the output of the auxiliary heater 50 is pre-stored and maintained in the storage device 216, etc.

[0089] Furthermore, the controller 200 is configured such that when the temperature detected by the temperature sensor 150 reaches a predetermined temperature T2, and the output of the auxiliary heater 50 exceeds a preset output limit, it can control the output of the auxiliary heater 50 to be changed below the output limit. This suppresses the temperature rise of the heating element of the auxiliary heater 50 and reduces the wear and deterioration of the heating element.

[0090] Furthermore, the controller 200 is configured such that, from the point where the temperature detected by the temperature sensor 150 reaches a predetermined temperature T2 until the temperature of each region detected by the temperature sensor 52 reaches the target temperature T1, the output of the auxiliary heater 50 can be varied within an output range above 0 and below a preset output limit value, or the output of the auxiliary heater 50 can be kept constant at a preset output value, wherein the preset output is above 0 and below a preset output limit value. This suppresses the temperature rise of the heating element of the auxiliary heater 50 and reduces the wear and deterioration of the heating element.

[0091] Furthermore, the controller 200 is configured such that, from the point where the temperature detected by the temperature sensor 150 reaches a predetermined temperature T2 until the temperature of each region detected by the temperature sensor 52 reaches the target temperature T1, the output of the auxiliary heater 50 can be set to 0, or the output of the auxiliary heater 50 can be varied by pulse output. The pulse output is a pulse output between a preset output value greater than 0 and an output limit value, and a 0 output value. This structure can also suppress the temperature rise of the heating wire of the auxiliary heater 50, reducing the wear and deterioration of the heating wire.

[0092] Furthermore, the controller 200 is configured such that when the temperature detected by the temperature sensor 150 reaches a predetermined temperature T2, and provided that the output of the auxiliary heater 50 does not exceed a preset output limit, the output of the auxiliary heater 50 can be controlled to fluctuate within a range below the output at the predetermined temperature T2 before the temperature of each region detected by the temperature sensor 52 reaches the target temperature T1. This configuration also suppresses the temperature rise of the heating element of the auxiliary heater 50, reducing the wear and deterioration of the heating element.

[0093] Thus, when the temperature detected by the temperature sensor 150 is above a predetermined temperature T2, if the output of the auxiliary heater 50 is below a preset output limit value, the controller 200 can heat both the heater 14 and the auxiliary heater 50. Therefore, according to the first method, the temperature rise of the heating wire of the auxiliary heater 50 can be suppressed, the wear and deterioration of the heating wire of the auxiliary heater 50 can be reduced, and thus the lifespan of the auxiliary heater 50 can be extended. Furthermore, by limiting the output of the auxiliary heater 50, the overall electrical load of the heater can be suppressed.

[0094] (Second method)

[0095] In the second method, the controller 200, based on the heating wire temperature and the furnace temperature, sets the heating rate of the auxiliary heater 50 to be lower than that of the heater 14. Before the heating wire temperature of the auxiliary heater 50, detected by the temperature sensor 150, reaches a predetermined temperature T2 that is lower than the target temperature T1, the controller 200 keeps the output of the auxiliary heater 50 constant. Then, when the heating wire temperature of the auxiliary heater 50 reaches or exceeds the predetermined temperature T2, the controller 200 sets the heating rate of the auxiliary heater 50 to be lower than that of the heater 14. Thus, as... Figure 5 As shown in (B), the peak value of the heating wire temperature of the auxiliary heater 50 can be lower than the peak value of the heating wire temperature in the comparative example, thereby suppressing the rise in the heating wire temperature of the auxiliary heater 50 and suppressing the deterioration of the heating wire of the auxiliary heater 50.

[0096] Alternatively, in the second configuration, the heating rate of the auxiliary heater 50 can be lower than that of the heater 14, starting from the heating towards the target temperature T1. Furthermore, since it is only necessary to suppress the temperature rise of the heating element of the auxiliary heater 50, as in the first configuration, an output limit value above the specified temperature T2 does not need to be set.

[0097] (Third method)

[0098] In the third method, the controller 200 delays the start of the output of the auxiliary heater 50 from the start of the output of the heater 14 based on the heating wire temperature and the furnace temperature. As an example, the controller 200 is configured to start the output of the auxiliary heater 50 after the temperature of region L detected by the temperature sensor 52 reaches a predetermined temperature T2. For example, the controller 200 is configured to allow the output of the auxiliary heater 50 to fluctuate within an output range below a preset output limit. This allows the setting of the time when the output of the auxiliary heater 50 is turned off (to zero). Thus, as... Figure 5As shown in (C), the peak temperature of the heating wire in the auxiliary heater 50 can be lower than the peak temperature of the heating wire in the comparative example, which can suppress the rise in the heating wire temperature of the auxiliary heater 50 and suppress the deterioration of the heating wire in the auxiliary heater 50. Furthermore, by limiting the output time of the auxiliary heater 50, it is expected to suppress the overall power load of the heater.

[0099] Furthermore, at this time, the controller 200 can keep the output of the auxiliary heater 50 constant at a preset output limit value. Also, since it is only necessary to suppress the temperature rise of the heating wire of the auxiliary heater 50, it is not necessary to set it to the same value as the output limit value in the first mode.

[0100] Next, use Figure 6 An example of a block diagram illustrating temperature control in this method is provided.

[0101] exist Figure 6 In this context, "target temperature" refers to the target temperature T1 in each region of heater 14. The target temperature T1 is input to the positive input terminal of the first subtractor.

[0102] "Furnace internal TC detected temperature" refers to the furnace internal temperature measured by temperature sensor 52 through thermocouples 303 corresponding to each region. The furnace internal temperature detected by temperature sensor 52 is input to the negative input terminal of the first subtractor. Thus, the furnace internal temperature is controlled to the corresponding target temperature T1.

[0103] The first subtractor calculates the deviation between the target temperature T1 and the furnace temperature, and outputs it to the PID calculation unit 1.

[0104] The PID calculation unit 1 takes the deviation from the first subtractor as input and performs a known PID calculation. The result of the PID calculation is input to the positive input of the second subtractor.

[0105] Additionally, "Heater TC Detected Temperature" refers to the heater temperature measured by thermocouple 302 corresponding to each region. The heater temperature detected by thermocouple 302 corresponding to each region is input to the negative input terminal of the second subtractor. Furthermore, for a specific region within each region, the temperature of the auxiliary heater 50 detected by thermocouple 304 can be input to the negative input terminal of the second subtractor.

[0106] The second subtractor calculates the deviation between the calculation result of the PID calculation unit 1 and the heater temperature, and outputs it to the PID calculation unit 2.

[0107] The PID calculation unit 2 takes the deviation from the second subtractor as input and performs a known PID calculation. The PID parameters used in the PID calculation unit 2 are different from those used in the PID calculation unit 1. The PID calculation result is output as an "operated quantity".

[0108] Furthermore, the PID parameters used in PID calculations in PID calculation unit 1 and PID calculation unit 2 are preferably adjustable. The PID parameters are an example of "control parameters for the heating unit" in the present disclosure. PID calculation unit 1 and PID calculation unit 2 are configured to allow for arbitrary setting of the PID parameters. The PID parameters, like the "target temperature," are recorded in the controller 200 as part of the process or a table accompanying the process.

[0109] "Operating quantity" refers to the value output as the result of control calculations corresponding to the area to be controlled. This value is converted into a control signal for heating the area to be controlled by heater 14 and output. When the output limit value of the auxiliary heater 50 is set as described above, the maximum value of this "operating quantity" is preset, thus limiting the maximum value of the control signal of the auxiliary heater 50.

[0110] As explained above, the controller 200 of the temperature control system disclosed herein is configured to perform control operations according to a control algorithm known as cascaded control, thereby controlling the furnace temperature to be consistent with the corresponding target temperature T1.

[0111] Next, use Figure 7 (A) and Figure 7 (B) An example of a substrate processing sequence performed by the substrate processing apparatus 10 will be described.

[0112] In step S101 (standby step), the standby temperature is maintained at the temperature before the wafer 2 is moved into the processing furnace 12 (or processing chamber 18). For example, in this embodiment, the standby temperature is the same as the target temperature T0, which is the film formation temperature. Furthermore, in step S101, the wafer 2 may be moved to the wafer boat 20, for example.

[0113] Step S102 (crystal boat loading step) is the step of placing the wafer 2 into the processing furnace 12 (or processing chamber 18). For example, in this embodiment, the wafer 2 is placed into the processing furnace 12 (or processing chamber 18) while held in the crystal boat 20. At this time, the temperature of the crystal boat 20 and the wafer 2 is lower than the target temperature T0, and the wafer 2 is placed into the processing furnace 12 (or processing chamber 18). As a result, the atmosphere (room temperature) outside the processing furnace 12 is introduced into the processing furnace 12 (or processing chamber 18), so the temperature inside the processing furnace 12 (or processing chamber 18) is temporarily lower than the target temperature T0. Afterwards, under the control of the controller 200, the furnace temperature stabilizes again at the target temperature T0 after a certain period of time. In this figure, it is illustrated that the target temperature T0 after placing the processing substrate into the processing furnace 12 (or processing chamber 18) and in the following step S103 is equal to that in step S101, but the target temperature after placement may be different depending on the requirements of step S103.

[0114] Step S103 (film formation process) is a step of performing film formation process by maintaining the furnace temperature at the target temperature T0 in order to perform the specified film formation process on wafer 2.

[0115] Step S104 (heating step) is the step of raising the furnace temperature from the target temperature T0 to the annealing temperature for annealing. In order to anneal the wafer 2 that has undergone film deposition, the controller 200 controls the heater 14 and the auxiliary heater 50 so that the furnace temperature reaches the target temperature T1, which is an annealing temperature higher than the target temperature T0. At this time, if the temperature of the heating wire of the auxiliary heater 50, detected by the temperature sensor 150, is above a predetermined temperature T2, which is lower than the target temperature T1, the controller 200 limits the output of the auxiliary heater 50.

[0116] Step S105 (annealing process) is a step to maintain the furnace temperature at the target temperature T1 for annealing wafer 2.

[0117] Step S106 (crystal boat unloading step) is a step of pulling the annealed wafer 2 and the crystal boat 20 out of the furnace 12 (or processing chamber 18) together.

[0118] If there are unprocessed wafers 2 that should be processed, the processed wafer 2 is removed from the crystal boat 20 and replaced with the unprocessed wafer 2. The above series of processes S101 to S106 are performed once.

[0119] <Effect>

[0120] According to this method, one or more of the following effects can be obtained.

[0121] Before reaching a specified temperature T2, which is lower than the target temperature T1, heating is performed without restriction using both heater 14 and auxiliary heater 50. During high-temperature processing above the specified temperature T2, by limiting the output of auxiliary heater 50, excessive temperature rise of the heating wire in auxiliary heater 50 can be suppressed, reducing wear and deterioration of the heating wire. Therefore, the lifespan of auxiliary heater 50 can be ensured.

[0122] Furthermore, heating is performed without restriction using both heater 14 and auxiliary heater 50 up to a specified temperature T2, which is lower than the target temperature T1. During high-temperature processing above the specified temperature T2, the output of auxiliary heater 50 is limited. Therefore, even if the output of auxiliary heater 50 exceeds its limit at the specified temperature T2, excessive temperature rise of the heating element in auxiliary heater 50 can be suppressed, reducing wear and tear on the heating element. This ensures the lifespan of auxiliary heater 50.

[0123] Furthermore, by limiting the output of the auxiliary heater 50, it is expected that the overall electrical load of the heater can be suppressed.

[0124] Furthermore, by using the auxiliary heater 50 to assist in heating the heater 14 corresponding to specific regions with large temperature variations, it is expected that the in-plane temperature uniformity of the wafer 2 disposed in each region containing the specific region can be improved. In addition, temperature uniformity between regions can also be ensured.

[0125] Furthermore, by using the auxiliary heater 50 to assist heating a specific area, the temperature within the processing container corresponding to each area can be raised to the target temperature T1 without delay. For example, the heating time (heating step) is not extended.

[0126] Furthermore, when heating to the target temperature T1, the heating rate of the auxiliary heater 50 can be made smaller than that of the heater 14. Therefore, even during high-temperature processing at temperatures higher than the specified temperature T2, excessive temperature rise of the heating wire of the auxiliary heater 50 can be suppressed, reducing the wear and deterioration of the heating wire of the auxiliary heater 50. Thus, the lifespan of the auxiliary heater 50 can be ensured.

[0127] Furthermore, when heating to the target temperature T1, the auxiliary heater 50 can start heating later than the heater 14. Therefore, even during high-temperature processing at temperatures higher than the specified temperature T2, excessive temperature rise of the heating wire of the auxiliary heater 50 can be suppressed, reducing wear and deterioration of the heating wire. Thus, the lifespan of the auxiliary heater 50 can be ensured.

[0128] The methods or variations described above can be used in appropriate combinations. The processing procedures and conditions can be set to be the same as those in the methods or variations described above. Furthermore, unless otherwise specified in the specification, each element is not limited to one and multiple elements may exist.

[0129] <Other methods>

[0130] The above provides a detailed explanation of the methods used in this disclosure. However, this disclosure is not limited to the methods described above, and various modifications may be made without departing from its core essence.

[0131] For example, the above description illustrates the application of this method when heating the temperature for annealing from the film-forming process, but this disclosure is not limited thereto and may also be appropriately applied to cases where this method is applied only when heating the temperature for film-forming and cases where this method is applied only when heating the temperature for annealing.

[0132] Furthermore, the above-described method illustrates an example of performing specified processing using a batch-type vertical assembly, i.e., a substrate processing apparatus, that processes multiple substrates at a time. This disclosure is not limited to the above-described method; for example, it can also be appropriately applied when performing specified processing using a monolithic substrate processing apparatus that processes one or several substrates at a time. Additionally, the above-described method illustrates an example of performing specified processing using a substrate processing apparatus equipped with a hot-wall type processing furnace. This disclosure is not limited to the above-described method; it can also be appropriately applied when performing specified processing using a substrate processing apparatus equipped with a cold-wall type processing furnace.

[0133] When using these substrate processing devices, each processing can be performed under the same processing procedures and conditions as described above or in the modified examples, and the same effects as described above or in the modified examples can be obtained.

[0134] Furthermore, the substrate processing apparatus of this disclosure can be applied not only to semiconductor manufacturing apparatuses for manufacturing semiconductors, but also to apparatuses for processing glass substrates, such as those used in LCD (Liquid Crystal Display) devices. The substrate processing includes, for example, CVD, PVD, forming oxide films, forming nitride films, forming metal-containing films, annealing, oxidation, nitriding, and diffusion processes. It can also be applied to various substrate processing apparatuses such as exposure apparatuses, coating apparatuses, drying apparatuses, and heating apparatuses.

[0135] Symbol Explanation

[0136] 14. Heater (First Heater)

[0137] 50 Auxiliary heaters (second heaters)

[0138] 52 Temperature sensor (first temperature sensor)

[0139] 150 Temperature sensor (second temperature sensor)

[0140] 200 Controller (Control Unit).

Claims

1. A temperature control system, characterized in that, have: The first heater is configured to be divided into regions and heats the processing container in which a substrate is disposed; The second heater assists in heating the first heater corresponding to a specific area in each of the regions; A temperature sensor detects the temperature of the second heater; and The control unit is configured to limit the output of the second heater when the temperature detected by the temperature sensor is above a predetermined temperature lower than the target temperature, thereby enabling the temperature inside the processing container to reach the target temperature.

2. The temperature control system according to claim 1, characterized in that, The control unit is configured such that when the temperature detected by the temperature sensor reaches the predetermined temperature, and the output of the second heater exceeds a preset output limit value, the output of the second heater is changed to be below the output limit value.

3. The temperature control system according to claim 1, characterized in that, The control unit is configured to, from the point where the temperature detected by the temperature sensor reaches the predetermined temperature until the temperature inside the processing container reaches the target temperature, cause the output of the second heater to vary within an output range that is above 0 and below a preset output limit value.

4. The temperature control system according to claim 1, characterized in that, The control unit is configured to maintain the output of the second heater at a preset output from the point where the temperature detected by the temperature sensor reaches the specified temperature until the temperature inside the processing container reaches the target temperature, wherein the preset output is greater than or equal to 0 and less than or equal to a preset output limit value.

5. The temperature control system according to claim 4, characterized in that, The control unit is configured to set the output of the second heater to 0 from the point where the temperature detected by the temperature sensor reaches the predetermined temperature until the temperature inside the processing container reaches the target temperature.

6. The temperature control system according to claim 3, characterized in that, The control unit is configured to: from the point where the temperature detected by the temperature sensor reaches the predetermined temperature until the temperature inside the processing container reaches the target temperature, cause the output of the second heater to vary in the form of pulse outputs, wherein the pulse outputs are pulse outputs between a preset output greater than 0 and below the output limit value and a 0 output.

7. The temperature control system according to claim 1, characterized in that, The control unit is configured such that, when the temperature detected by the temperature sensor reaches the specified temperature, and provided that the output of the second heater does not exceed a preset output limit, before the temperature inside the processing container reaches the target temperature, the output of the second heater varies within a range below the output at the specified temperature.

8. The temperature control system according to any one of claims 1 to 7, characterized in that, The control unit is configured such that when the temperature detected by the temperature sensor is above the predetermined temperature, if the output of the second heater is below a preset output limit value, heating can be performed by both the first heater and the second heater.

9. The temperature control system according to claim 1, characterized in that, The control unit is configured to keep the output of the second heater constant until the temperature detected by the temperature sensor reaches the predetermined temperature.

10. The temperature control system according to claim 1, characterized in that, The control unit is configured to combine the heating of both the first heater and the second heater, or to use the heating of the first heater alone, thereby heating the temperature inside the processing container opposite each of the regions to the target temperature.

11. The temperature control system according to claim 10, characterized in that, The control unit is configured to start the output of the second heater after starting the output of the first heater.

12. The temperature control system according to claim 11, characterized in that, The control unit is configured to cause the second heater to output when the temperature detected by the temperature sensor reaches the predetermined temperature.

13. The temperature control system according to claim 12, characterized in that, The control unit is configured to cause the output of the second heater to vary within an output range below a preset output limit value.

14. The temperature control system according to claim 12, characterized in that, The control unit is configured to keep the output of the second heater constant at a level below a preset output limit value.

15. The temperature control system according to claim 1, characterized in that, The control unit is configured to make the heating rate of the second heater lower than the heating rate of the first heater.

16. The temperature control system according to claim 15, characterized in that, The target temperature is set higher than the temperature that the second heater can control.

17. The temperature control system according to claim 1, characterized in that, The temperature control system includes a first temperature sensor that detects the temperature inside the processing container. The specific area is the area with the largest temperature fluctuation detected by the first temperature sensor among all areas.

18. A temperature control method, characterized in that, It has the following processes: The temperature control system described in claim 1 enables the temperature inside the processing container to reach the target temperature.

19. A method for manufacturing a semiconductor device, characterized in that, It has the following processes: The substrate is processed while maintaining the target temperature using the temperature control method of claim 18.

20. A substrate processing apparatus, characterized in that, have: The first heater is configured to be divided into regions and heats the processing container in which a substrate is disposed; The second heater assists in heating the first heater corresponding to a specific area in each of the regions; A temperature sensor detects the temperature of the second heater; and The control unit is configured to limit the output of the second heater when the temperature detected by the temperature sensor is above a predetermined temperature lower than the target temperature, thereby enabling the temperature inside the processing container to reach the target temperature.

Images