HEATER UNIT, MULTILAYER STRUCTURE, PROCESSING APPARATUS, AND METHOD FOR PRODUCING SEMICONDUCTOR DEVICE

Abstract

The present invention improves energy conservation of a device.　This heater unit comprises a thermal insulation portion including a heating portion that heats the inside of a reaction tube, and a multilayer portion provided outside the thermal insulation portion and having an internal space. The multilayer portion includes a plurality of heat insulators along a direction from the thermal insulation portion toward the outside, and a space is formed between the heat insulators. The heater unit is configured such that the amount of heat emitted from the multilayer portion can be changed in accordance with the heat conductivity in the space and the thermal emittance of the heat insulators.

Description

[Technical Field]

[0001] The present disclosure relates to a heater unit, a multilayer structure, a processing apparatus, and a method for manufacturing a semiconductor device. [Background technology]

[0002] As one step in the manufacturing process of semiconductor devices, a process of forming a film on a substrate may be performed (see, for example, Patent Documents 1 to 3, etc.). In recent years, environmental adaptation has been required not only for semiconductor factories but also for factories, and energy conservation is being mainly required for facilities (equipment, etc.) within the factory. In particular, the equipment shown in Patent Documents 1 to 3, etc. requires a large amount of power when processing substrates, and therefore further energy conservation is required. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-214283 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-029597 [Patent Document 3] Japanese Patent Application Publication No. 2018-088520 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides techniques that can improve the energy efficiency of devices. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, a heat insulating section having a heat generating section for heating the inside of the reaction tube; a multi-layer section provided outside the heat insulating section and having a space therein, The multilayer section has a plurality of thermal insulators along a direction from the thermal insulator toward the outside, and a space is formed between each thermal insulator, and a technology is provided in which the amount of heat dissipation of the multilayer section can be changed depending on the thermal conductivity in the space and the thermal emissivity of the thermal insulators. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to improve the energy efficiency of the device. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a longitudinal cross-sectional view showing an outline of a substrate processing apparatus according to an aspect of the present disclosure. [Figure 2] 2 is a cross-sectional view showing an outline of a heater unit of the substrate processing apparatus of FIG. 1. FIG. [Figure 3] 2 is a detailed cross-sectional view showing a support body of a heat insulator positioned on a side surface of the substrate processing apparatus of FIG. 1. FIG. [Figure 4] 2 is a detailed cross-sectional view showing a support body of a heat insulator located on the upper surface of the substrate processing apparatus of FIG. 1. FIG. [Figure 5] FIG. 1 is a schematic configuration diagram of a controller of a substrate processing apparatus according to an embodiment of the present disclosure, showing a control system of the controller in a block diagram. [Figure 6] FIG. 10 is a schematic configuration diagram illustrating a modified example of the heater unit of the present disclosure. [Figure 7] Fig. 7(A) is a cross-sectional view showing an outline of a heater unit of the substrate processing apparatus according to the embodiment, and Fig. 7(B) is a diagram showing the relationship between the distance from the center of the reaction tube and the temperature when a film formation process is performed using the substrate processing apparatus according to the embodiment. [Figure 8] 8A is a cross-sectional view showing an outline of a heater unit of a substrate processing apparatus according to a comparative example, and FIG. 8B is a graph showing the relationship between the distance from the center of a reaction tube and the temperature when a film formation process is performed using the substrate processing apparatus according to the comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0008] The following description will be made with reference to Figures 1 to 6. Note that all drawings used in the following description are schematic, and the dimensional relationships, ratios, etc. of elements shown in the drawings do not necessarily match those of reality. Furthermore, the dimensional relationships, ratios, etc. of elements between multiple drawings do not necessarily match.

[0009] (1) Configuration of the substrate processing equipment The configuration of a substrate processing apparatus 1 as a processing apparatus for processing a substrate will be described with reference to FIG.

[0010] The substrate processing apparatus 1 is composed of a cylindrical reaction tube 20 having an integrally formed upper surface and side surface and an open lower surface, a boat 40 loaded with wafers 41 as substrates and stored in the reaction tube 20, and a heater unit 200 equipped with a heater 2 as a heat generating part that heats the inside of the reaction tube 20 from the side.

[0011] In this substrate processing apparatus 1, a heat equalizer 3 is provided within a heater 2, and a reaction tube 20 is provided within the heat equalizer 3. The heat equalizer 3 is made of a material with high thermal conductivity (e.g., SiC material) and is used to maintain temperature uniformity within the reaction tube 20. The heat equalizer 3 is formed in a cylindrical shape with its top and side surfaces integrally formed and its bottom open, and has an outwardly extending flange formed at its bottom end.

[0012] The heater 2 is arranged between the inner heat insulating portion 73 and the heat equalizer pipe 3 in a cylindrical shape, and is divided into a plurality of parts, one above the other.

[0013] The reaction tube 20 is provided at its lower part with one gas inlet pipe (gas inlet passage) 5 and one exhaust pipe (gas exhaust passage) 6, each of which has an internal space and communicates with the inside of the reaction tube 20.

[0014] Gas inlet pipe 5 is provided with, in order from the upstream side, a gas supply source 5a, a mass flow controller (MFC) 5b which is a flow rate controller (flow rate control section), and a valve 5c. An inert gas inlet pipe 7 is connected to gas inlet pipe 5 on the downstream side of valve 5c. Inert gas inlet pipe 7 is provided with, in order from the upstream side, an inert gas supply source 7a, MFC 7b, and valve 7c.

[0015] The exhaust pipe 6 is provided with, in this order from the upstream side, a pressure sensor 6a as a pressure detector (pressure detection unit) that detects the pressure inside the reaction tube 20, an APC (Auto Pressure Controller) valve 6b, and a vacuum pump 6c as a vacuum exhaust device. The exhaust pipe 6, the pressure sensor 6a, the APC valve 6b, and the vacuum pump 6c constitute an exhaust device 600. The exhaust device 600 is configured to be able to evacuate the reaction tube 20 so that the pressure inside the reaction tube 20 reaches a predetermined pressure (degree of vacuum).

[0016] The reaction tube 20 has an opening at the bottom end which serves as an inlet, through which a plurality of wafers 41 loaded in a boat 40 in a horizontal position are introduced and removed. That is, the boat 40 is introduced into the reaction tube 20 from below by being raised by the lifting mechanism 115, and is removed from the reaction tube 20 by being lowered.

[0017] A flange 62 is provided around the lower end of the reaction tube 20, and an airtight seal (for example, an O-ring) 63 is provided between the flange 62 and the furnace opening lid 61 when the furnace opening lid 61 is closed.

[0018] The equalizer tube 3 and the reaction tube 20 are designed to be removable for assembly and maintenance (cleaning, etc.). The equalizer tube 3 is sealed to the inner heat insulating part 73 with an airtight seal (e.g., O-ring) 65, and the reaction tube 20 is sealed to the equalizer tube 3 with an airtight seal (e.g., O-ring 66).

[0019] The boat 40 is provided with a rotation mechanism 64 for rotating the boat 40. Furthermore, a plurality of heat insulating plates 60 (e.g., quartz plates) are loaded in the lower part of the boat 40. The heat insulating plates 60 are provided to prevent uneven temperature distribution above and below the wafers 41 placed on top.

[0020] Next, the heater unit 200 will be described in detail with reference to FIGS.

[0021] The heater unit 200 includes a heater 2, an inner heat insulating section 73 as a heat insulating section, an outer heat insulating section 74 as a heat insulating section, and a multilayer section 70 provided between the inner heat insulating section 73 and the outer heat insulating section 74. The heater unit 200 is a multilayer structure composed of the heater 2, the inner heat insulating section 73, the multilayer section 70, and the outer heat insulating section 74.

[0022] The inner heat insulating part 73 is formed so as to cover the periphery of the top surface and side surface of the reaction tube 20. The outer heat insulating part 74 is configured so as to cover the periphery of the top surface and side surface of the inner heat insulating part 73. The heater 2 is attached to the inside of the side surface of the inner heat insulating part 73. The inner heat insulating part 73 and the outer heat insulating part 74 are configured to insulate against heat from the heater 2.

[0023] The multilayer section 70 is configured to have a plurality of heat insulators 72 arranged in a direction from the inner heat insulator 73 toward the outside. A space S is formed between each heat insulator 72. In other words, the multilayer section 70 is provided outside the inner heat insulator 73 and is configured to have a space S inside. In other words, the multilayer section 40 is configured so that the heat insulators 72 and the spaces S are arranged alternately.

[0024] That is, a plurality of heat insulators 72 are provided on the side surface of the heater unit 200 with a space S between them on the outer circumferential side of the inner heat insulator 73, and are fastened and supported to the outer heat insulator 74 with supports 75. A plurality of heat insulators 72 are also provided on the top surface of the heater unit 200 with gaps between them in the heat insulating direction, and are fastened and supported to the outer heat insulator 74 with supports 100. The heat insulators 72 have exhaust holes 10 drilled in several places.

[0025] 1 shows five insulators 72 on the side surface of the heater unit 200, but as shown in FIG. 2, the number of insulators 72 on the side surface of the heater unit 200 in the present disclosure is preferably five or more, for example, ten. By providing ten insulators 72 as the multilayer section 70, heat transfer inside the reaction tube 20 in a high-temperature state can be effectively suppressed. Furthermore, by providing five or more insulators 72, it is possible to further reduce the amount of heat radiation from inside the furnace, thereby improving the energy saving of the apparatus.

[0026] Furthermore, the multilayer section 70 is also provided in the ceiling section 200a of the heater unit 200 between the inner heat insulating section 73 and the outer heat insulating section 74, and a plurality of, for example, two heat insulating bodies 72 are arranged substantially horizontally with the ceiling surfaces of the inner heat insulating section 73 and the outer heat insulating section 74. The ceiling section 200a is provided above the reaction tube 20.

[0027] The width of the space S and the thickness of the insulators 72 are set so that the combined outer diameter of the inner insulator 73, the multilayer section 70, and the outer insulator 74 on the side of the heater unit 200 is approximately the same as the outer diameter of the ceiling section 200a, and so that the number of insulators 72 is maximized. When the thickness of the insulators 72 is, for example, 2.0 mm, the number of insulators 72 is preferably 10. By increasing the number of insulators 72 provided in the multilayer section 70, the amount of heat dissipated from the furnace can be significantly reduced. This prevents unnecessary power from being supplied to the heater 2, thereby improving energy conservation. The thickness of the insulators 72 is set to a few millimeters, for example, between 1.0 mm and 3.0 mm, taking strength into consideration.

[0028] A member made of metal or alloy is used as the insulator 72. A member having a thermal emissivity of 0.02 or more and 0.1 or less is used as the insulator 72. The thermal emissivity of 0.02 for the member used as the insulator 72 is the limit value that can be achieved by surface treatment of a member having a melting point of 1000°C or more, as described below. As long as the melting point is not 1000°C or more, the thermal emissivity may be 0.02 or less. In other words, even a thermal emissivity of approximately 0.01 can be achieved by surface treatment. By reducing the surface treatment to 0.1 or less, high thermal insulation performance can be achieved. By setting the melting point of the member used as the insulator 72 to be equal to or higher than the set temperature inside the reaction tube 20, heat resistance can be ensured.

[0029] Specifically, a material with a melting point of 1000°C or higher, such as gold (Au) or molybdenum (Mo), is used as the heat insulator 72. By selecting such a material to form the multilayer section 70, the amount of heat dissipated from inside the furnace can be significantly reduced, and therefore, power is not supplied to the heater 2 unnecessarily, thereby improving energy conservation.

[0030] The set temperature inside the reaction tube 20 is set appropriately depending on the process (film formation process, oxidation-diffusion process, annealing process) performed inside the reaction tube 20, and even in the case of film formation process, it is set appropriately depending on the film type. The above-mentioned 1000°C is merely one example of a set temperature that can be used for almost all processes (film formation process, oxidation-diffusion process, annealing process). In the future, a material (metal) for the heat insulator 72 can be selected depending on the process. For example, a material with a melting point higher than the temperature at which the process will be performed inside the reaction tube 20 can be selected.

[0031] The thickness of the inner insulation part 73 and the outer insulation part 74 are each configured to be thicker (larger) than the thickness of the insulator 72 and wider (larger) than the width of the space S formed between the insulators 72. By making the inner insulation part 73 thicker than the insulator 72, the heater 2 is easily held. By making the outer insulation part 74 thicker than the insulator 72, the insulator 72 is easily supported. Furthermore, by lowering the thermal emissivity of the insulator 72, making the width of the space S narrower than the thickness of the inner insulation part 73 and the outer insulation part 74, and increasing the number of insulators 72, the amount of heat dissipation from inside the furnace is reduced. In other words, the insulation performance of the heater unit 200 can be improved.

[0032] The multilayer section 70 is formed by combining a cylindrical inner heat insulating section 73, whose top and side surfaces are integrally formed and whose bottom surface is open, with a cylindrical outer heat insulating section 74, whose top and side surfaces are integrally formed and whose bottom surface is open, by tightly sealing their lower ends together. That is, the side and top surfaces of the reaction tube 20 are covered with a multilayer structure consisting of the inner heat insulating section 73 equipped with the heater 2, the multilayer section 70, and the outer heat insulating section 74.

[0033] Furthermore, the heat insulators 72 are configured so that the width of the space S can be changed by changing the number of heat insulators 72 in the multilayer portion 70 according to the thermal emissivity and thickness of the heat insulators 72 .

[0034] For example, when it is desired to reduce the amount of heat dissipation from within the furnace (when it is desired to improve the thermal insulation performance of the apparatus during temperature rise, substrate processing, etc.), the width of the space S is set so as to maximize the number of insulators 72 in the multi-layer section 70. On the other hand, when it is desired to increase the amount of heat dissipation from within the furnace, the width of the space S is set so as to reduce the number of insulators 72 in the multi-layer section 70.

[0035] A gas supply pipe (gas introduction passage) 302 serving as a gas supply section for supplying a predetermined gas into the multi-layer section 70, and a gas exhaust pipe (gas exhaust passage) 304 are provided at the bottom of the heater unit 200, and a gas exhaust pipe 80 is provided at the top of the heater unit 200, approximately in the center of the ceiling section 200a. Each of these pipes is in communication with a space S formed between each heat insulator 72 within the multi-layer section 70.

[0036] The gas supply pipe 302 is provided with, in order from the upstream side, a gas supply source 302a, a mass flow controller (MFC) 302b which is a flow rate controller (flow rate control section), and a valve 82. The predetermined gas supplied from the gas supply source 302a is a gas having a higher thermal conductivity than air, such as a rare gas. Examples of the predetermined gas that can be used include helium (He) gas and hydrogen (H2) gas. Needless to say, the gas supply source 302a may be configured to allow a liquid heat transfer medium to flow in addition to a gaseous heat transfer medium such as a gas.

[0037] The gas exhaust pipe 80 is provided with a valve 83. The gas exhaust pipe 80 is configured to exhaust the cooling gas supplied from the gas supply pipe 302 into the multi-layer section 70 to the outside of the multi-layer section 70.

[0038] The gas exhaust pipe 304 is provided with, in order from the upstream side, an APC valve 81 and a vacuum pump 71. The APC valve 81 and the vacuum pump 71 constitute an exhaust device 300. The exhaust device 300 is configured to evacuate the atmosphere in the space S formed between the heat insulators 72. The exhaust device 300 is configured to be able to reduce the pressure in the space S formed between the heat insulators 72 to a vacuum level that almost eliminates heat dissipation by conductive heat. That is, the vacuum pump 71 is connected to the multilayer section 70 via the APC valve 81, and the multilayer section 70 is configured to have a vacuum insulation function by opening the APC valve 81 and using the vacuum pump 71 to draw a vacuum.

[0039] The exhaust device 300 is configured to be able to reduce the pressure in the space S formed between each of the thermal insulators 72 to less than 200 Pa. In this way, by creating a vacuum state in the space S between each of the thermal insulators 72, for example, at less than 200 Pa, it is possible to suppress heat dissipation due to conductive heat. In other words, when it is desired to improve the thermal insulation performance of the apparatus during substrate processing, such as when the temperature inside the furnace is rising, it is possible to suppress heat dissipation (heat escape) from the heater unit 200 to radiant heat only, thereby improving energy conservation.

[0040] Furthermore, with the APC valve 81 closed and valves 82 and 83 open, a gas with high thermal conductivity is supplied from the gas supply pipe 302 to the space S formed between the insulators 72, and the gas circulated through the space S is exhausted to the outside of the apparatus via the gas exhaust pipe 80. By supplying a gas with high thermal conductivity to the space S between the insulators 72 in this manner, the amount of heat dissipated (heat escape) from the heater unit 200 can be increased through heat dissipation by conduction in addition to radiant heat, thereby significantly shortening the time required to cool the furnace. Alternatively, the space S may be filled with a gas with high thermal conductivity without being exhausted to the outside of the apparatus via the gas exhaust pipe 80. In this case, the APC valve 81 is adjusted to adjust the pressure in the space S formed between the insulators 72 to 200 Pa or higher.

[0041] Note that a plurality of valves 82 may be provided in the circumferential direction to ensure uniform cooling. Furthermore, the holes 10 drilled in the heat insulator 72 may be drilled so as to reduce the pressure loss in the lower portion of the heat insulator 72 compared to the pressure loss in the upper portion, in order to allow the predetermined gas 111 to flow uniformly within the space S during cooling (for example, the diameter of the holes 10 drilled in the lower portion of the heat insulator 72 may be made larger than that of the upper portion, or the number of holes may be increased).

[0042] Next, the installation of the heat insulator 72 will be described with reference to Figures 3 and 4. Note that Figures 3 and 4 are merely examples, and the manner in which the heat insulator 72 may be installed is not limited to these. As shown in Figure 3, the heat insulator 72 is fitted into a groove in a support bracket 101 made of, for example, glass fiber material. This support bracket 101 is fastened and supported to the outer heat insulator part 74 by screws 102 made of, for example, glass fiber material. The support structure 75 is applied in a similar structure above and below the heat insulator 72. This allows the heat insulator 72 to be supported in a thermally insulating manner by the outer heat insulator part 74. The support bracket 101 and the screws 102 have low thermal conductivity, and therefore provide a heat insulating effect.

[0043] As shown in Fig. 4, the support body 100 is configured to include a support part 103 and screws 102 and 104. The support part 103 is made of, for example, a glass fiber material, and is fastened and supported to the outer insulation part 74 by the screw 102 described above. The support part 103 is then passed through a perforated part of the insulation body 72, and the outer insulation part 74 is received by the screw 104, which is made of, for example, the glass fiber material described above.

[0044] The inner heat insulating part 73 has a flange 77 that extends outward at its lower end, and the outer heat insulating part 74 has a flange 76 that extends outward at its lower end. The inner heat insulating part 73 and the outer heat insulating part 74 have a multi-layer structure in which the inner heat insulating part 73 is inserted from below the outer heat insulating part 74 to which the heat insulator 72 is fastened and supported, and the flanges 76, 77 provided on each part are sealed airtightly via an O-ring 78, for example, and have a removable structure.

[0045] Next, a controller serving as a control section (control means) will be described with reference to Fig. 5. The substrate processing apparatus 1 has a controller 500 that controls the operation of each section of the substrate processing apparatus 1.

[0046] 5 shows an outline of the controller 500. The controller 500 is configured as a computer including a CPU (Central Processing Unit) 501, a RAM (Random Access Memory) 502, a storage device 503 as a storage unit, and an I / O port 504. The RAM 502, the storage device 503, and the I / O port 504 are configured to be able to exchange data with the CPU 501 via an internal bus 505.

[0047] The controller 500 is provided with a network transmission / reception unit 583 that is connected to the host device 570 via a network. The network transmission / reception unit 583 is capable of receiving information about the processing history and processing schedule of the substrate S from the host device 570.

[0048] The storage device 503 is configured by, for example, a flash memory, an HDD (Hard Disk Drive), etc. A control program for controlling the operation of the substrate processing apparatus 1, a process recipe describing the procedures and conditions of a semiconductor device manufacturing method (to be described later), etc. are readably stored in the storage device 503.

[0049] The process recipe functions as a program, which is a combination of procedures in a substrate processing step (described later) that are executed by the controller 500 to obtain a predetermined result. Hereinafter, the process recipe, control program, etc. are collectively referred to as simply a program. In this specification, the term "program" may refer to only a process recipe, only a control program, or both. The RAM 502 is configured as a memory area (work area) in which programs, data, etc. read by the CPU 501 are temporarily stored.

[0050] The I / O port 504 is connected to each component of the substrate processing apparatus 1.

[0051] The CPU 501 is configured to read and execute a control program from the storage device 503, and also to read a process recipe from the storage device 503 in response to an input of an operation command from the input / output device 581. The CPU 501 is configured to be able to control the substrate processing apparatus 1 in accordance with the contents of the read process recipe.

[0052] The controller 500 according to this embodiment can be configured by installing the program into a computer using an external storage device 582 (for example, a magnetic disk such as a hard disk, an optical disk such as a DVD, a magneto-optical disk such as an MO, or a semiconductor memory such as a USB memory) storing the program. The means for supplying the program to the computer is not limited to supplying the program via the external storage device 582. For example, the program may be supplied via a communication means such as the Internet or a dedicated line, without going through the external storage device 582. The storage device 503 and the external storage device 582 are configured as computer-readable recording media. Hereinafter, these are collectively referred to simply as recording media. In this specification, the term "recording medium" may refer to the storage device 503 alone, the external storage device 582 alone, or both.

[0053] Next, as one step of the semiconductor manufacturing process (substrate processing process), a step of forming a film on wafer 41 using substrate processing apparatus 1 having the above-described configuration will be described. In the following description, the operation of each part constituting substrate processing apparatus 1 is controlled by controller 500.

[0054] When a plurality of wafers 41 are loaded into the boat 40 (wafer charging), the boat 40 holding the plurality of wafers 41 is lifted by the lifting mechanism 115 and carried into the reaction tube 20 (boat loading). In this state, the furnace opening cover 61 seals the lower end of the reaction tube 20 via the airtight seal 63.

[0055] The pressure inside the reaction tube 20 is controlled to a predetermined pressure. The inside of the reaction tube 20 is heated by the heater 2 to a desired temperature. At this time, the state of power supply to the heater 2 is feedback-controlled based on temperature information detected by a temperature sensor so that the inside of the reaction tube 20 has a desired temperature distribution. Next, the heat insulating plate 60 and the boat 40 are rotated by the rotation mechanism 64, thereby rotating the wafers 41.

[0056] At this time, valves 82 and 83 are closed and the exhaust device 300 is operated to exhaust the atmosphere in the space S formed between each insulator 72, and the atmosphere in the space S formed between each insulator 72 is made into a vacuum state.

[0057] Next, the valve 5c is opened, and the process gas supplied from the gas supply source 5a and controlled to a desired flow rate by the MFC 5b is introduced into the gas inlet pipe 5. The process gas introduced into the gas inlet pipe 5 is introduced into the reaction tube 20.

[0058] The processing gas introduced into the reaction tube 20 comes into contact with the surfaces of the wafers 41, and processes such as oxidation and diffusion are performed on the wafers 41. At this time, since the boat 40 is rotated, the wafers 41 are also rotated, and therefore the processing gas comes into contact with the surfaces of the wafers 41 evenly.

[0059] Furthermore, the exhaust device 600 is configured to exhaust the process gas introduced into the gas inlet pipe 5 into the reaction tube 20 at a predetermined flow rate. This allows the exhaust device 600 to quickly exhaust outgassing during heat treatment, for example.

[0060] After a preset processing time has elapsed, valve 5c is closed, and valve 7c is opened to supply an inert gas from inert gas supply source 7a. Then, the atmosphere in reaction tube 20 is replaced with the inert gas, the temperature of wafers 41 is decreased (cooled down), and the pressure in reaction tube 20 is returned to normal pressure.

[0061] At this time, the APC valve 81 is closed, and the valves 82 and 83 are opened, and a predetermined gas 111 is supplied into the space S formed between the heat insulators 72, so that the inside of the reaction tube 20 is cooled rapidly.

[0062] Thereafter, the furnace opening cover 61 is lowered by the lifting mechanism 115 to open the lower end of the reaction tube 20, and the processed wafers 41 held in the boat 40 are unloaded from the lower end of the reaction tube 20 to the outside of the reaction tube 20 (boat unloading). Thereafter, the processed wafers 41 are removed by the boat 40 (wafer discharging).

[0063] Therefore, by using the heater unit 200, the amount of heat dissipated from the heater unit 200 can be adjusted. That is, by making the space S a vacuum state when the heater unit 200 is operating, including during temperature rise, it is possible to improve the heat insulating performance and expect to realize energy savings, and by supplying a gas with high thermal conductivity to the space S during temperature fall (for example, by stopping the heater unit 200 (turning off the heater power)), it is possible to significantly shorten the temperature fall time. In this way, rapid temperature rise and fall can be efficiently achieved. Also, a rapid cooling mechanism may be separately provided, and a cooling gas may be supplied between the soaking tube 3 and the inner insulation part 73 during temperature fall.

[0064] According to the present disclosure, heat dissipation due to conductive heat can be suppressed by creating a vacuum state in the space S formed between the heat insulators 72, for example, at a pressure of several Pa. Therefore, heat dissipation (heat escape) from the heater 2 can be suppressed.

[0065] That is, since the multilayer section 70 is configured so that the spaces S between the heat insulators 72 can be evacuated, the amount of heat dissipated from the furnace can be reduced by evacuating the spaces S when the furnace is heated or when substrates are processed, thereby significantly improving the heat insulating performance of the multilayer section 70. As a result, energy savings can be improved.

[0066] Furthermore, according to the present disclosure, by supplying a gas with high thermal conductivity to the space S formed between the heat insulators 72, it is possible to increase the heat radiation (heat escape) from the heater 2. Therefore, it is possible to significantly shorten the temperature drop time inside the reaction tube 20.

[0067] In other words, since the multilayer section 70 is configured to be able to supply a gas with high thermal conductivity to the space S between each insulator 72, when the temperature inside the furnace is decreasing, by supplying a gas with high thermal conductivity to the space S, the amount of heat dissipated from inside the furnace is increased, and the temperature inside the furnace can be rapidly decreased.

[0068] Furthermore, according to the present disclosure, the amount of heat dissipated from the multilayer unit 70 can be adjusted according to the thermal conductivity of the space S and the thermal emissivity of the heat insulator 72, and the amount of heat dissipated from inside the furnace can be adjusted. This is expected to achieve appropriate energy savings according to the substrate processing.

[0069] Furthermore, by using a material with low thermal emissivity as the heat insulator 72 and increasing the number of heat insulators 72 in the multilayer section 70, the amount of heat dissipation can be significantly reduced compared to conventional configurations. As a result, no unnecessary power is supplied to the heater 2, and energy savings are expected to be improved compared to conventional configurations.

[0070] (Variation) Next, a modified example of the heater unit 200 in the above-described embodiment will be described in detail with reference to Fig. 6. Only the differences from the above-described embodiment will be described in detail below.

[0071] The heater unit 700 according to this modification can be divided into multiple regions. As shown in FIG. 6, the heater unit 700 is divided into five control zones U, CU, C, CL, and L from the top to the bottom of the side surface. That is, the inner heat insulating section 73, the multilayer section 70, and the outer heat insulating section 74 on the side surface of the heater unit 700 are divided into five control zones U, CU, C, CL, and L, and each zone can be configured to create a vacuum inside the multilayer section 70 or supply a gas with high thermal conductivity. Each control zone is provided with a pair of thermocouples, allowing control based on the temperature in each zone. The exhaust device 300 is configured to individually adjust the pressure of the space S for each region to a range of 0 to less than 200 Pa.

[0072] That is, according to this modification, in addition to the effects of the heater unit 200 described above, it is possible to control the heater unit for each control zone, and individual, precise temperature control is possible.

[0073] (Other aspects) In the above embodiment, the multi-layer unit 70 has been described as having a plurality of thermal insulators 72 with spaces S formed between the insulators. However, the present disclosure is not limited to this. The multi-layer unit 70 may also be configured to have a plurality of thermal insulators 72 with thermal insulators such as thermal insulation sheets sandwiched (filled) in the spaces S formed between the insulators. This can further reduce the amount of heat dissipated from inside the furnace. In other words, the thermal insulation performance of the heater unit 200 can be improved.

[0074] Furthermore, in the above embodiment, the insulator 72 is described as being made of a metal or alloy such as gold or molybdenum, but the present disclosure is not limited to this. For example, aluminum, brass, chromium, copper, etc. can be used depending on the surface treatment state, such as the polishing state or oxidation state, and the treatment temperature used.

[0075] Furthermore, in the above embodiment, the multi-layer portion 70 on the side surface of the heater unit 200 has been described, but the present invention can also be applied to the multi-layer portion 70 on the ceiling portion 200a, which is the upper surface of the heater unit 200.

[0076] In the above embodiment, a film formation process is described as a process performed by a substrate processing apparatus, but the present disclosure is not limited to this and can be applied not only to semiconductor manufacturing apparatuses but also to apparatuses that process glass substrates, such as LCD devices. Film formation processes include, for example, CVD, PVD, processes for forming oxide films, nitride films, or both, and processes for forming films containing metals. Furthermore, the present disclosure can be similarly applied to processes such as annealing, oxidation, nitriding, and diffusion.

[0077] Although various exemplary embodiments of the present disclosure have been described above, the present disclosure is not limited to these embodiments and can be used in appropriate combinations.

[0078] Examples will be described below. [Example]

[0079] In this example, the substrate processing process described above was performed using a substrate processing apparatus 1 equipped with a heater unit 200 shown in FIG. 7(A). In the comparative example, the substrate processing process described above was performed using a substrate processing apparatus equipped with a heater unit 800 shown in FIG. 8(A). FIG. 7(B) is a diagram showing the relationship between the distance from the center of the reaction tube and the temperature when a film formation process is performed using the substrate processing apparatus of this example. FIG. 8(B) is a diagram showing the relationship between the distance from the center of the reaction tube and the temperature when a film formation process is performed using the substrate processing apparatus of the comparative example.

[0080] If the temperature at the heater 2 is T1°C and the temperature at the heat insulator 72a on the heater 2 side is T2°C, the amount of heat Q1 transferred from the heater 2 to the heat insulator 72a by radiant heat is

[0081]

number

[0082] Similarly, the temperature at the second insulator 72b from the heater 2 side is T3°C, the temperature at the third insulator 72c from the heater 2 side is T4°C, and the temperature at the nth insulator 72n from the heater side is T n °C, the amount of heat transferred between each insulator is

[0083]

number

[0084] Now, if we add up all of Q1 to Qn, we get

[0085]

number

[0086]

number

[0087] In other words, if there are n heat insulators, the amount of heat radiated from the heater 2 to the outside will be 1 / n times smaller than when there is one heat insulator. Also, the thermal emissivity of the heat insulators is low, and the more heat insulators there are, the less heat will be radiated.

[0088] In this example, the heat insulators 72a to 72j used were members with a thickness t of 2 mm, a thermal emissivity ε of 0.1, and a thermal conductivity λ of 50 W / mK. The width of the space S was 4 mm, the number of heat insulators 72 was 10, the thermal conductivity of the space S in a vacuum state was λg = 0 W / mK, and the thermal conductivity of the space S when helium gas was supplied to the space S was λg = 0.25 W / mK.

[0089] When heating is performed at a heater temperature of 800° C. (when the space S is a vacuum), the amount of heat radiation Q is calculated to be 1280 W using the above equations 1 to 3, since only the radiant heat between the heat insulators 72 needs to be considered.

[0090] In addition, when the heater temperature is lowered from 800°C (when helium gas is supplied to space S), the heat dissipation amount Q was calculated to be 9603 W by adding the heat dissipation amount due to radiant heat, the heat dissipation amount due to conductive heat in each insulator 72, and the heat dissipation amount due to conductive heat between each insulator 72 (conductive heat when helium gas is supplied to space S).

[0091] Therefore, it was confirmed that supplying helium gas to the space S in the multi-layer section 70 increases the amount of heat released during temperature drop to about 7.5 times the amount of heat released during temperature rise.

[0092] In contrast, in the heater unit 800 of the comparative example, when the heater temperature was set to 800°C, the temperature on the outer surface of the outer insulation section 74, which was 620 mm away from the center of the heater unit, reached 200°C, and the amount of heat dissipation Q moving from the inside of the inner insulation section 73 to the outside of the outer insulation section 74 was calculated to be 5850 W.

[0093] That is, when the heater unit 200 of this embodiment is used, it has been confirmed that the amount of heat dissipation can be reduced by approximately 80% by creating a vacuum in the space S compared to when the heater unit 800 of the comparative example is used. Also, when the heater unit 200 of this embodiment is used, it has been confirmed that the amount of heat dissipation can be increased by 1.6 times by supplying helium gas to the space S compared to when the heater unit 800 of the comparative example is used.

[0094] Therefore, by using the heater unit 200, the amount of heat released from the heater unit 200 can be adjusted, which not only saves energy but also improves productivity. By creating a vacuum in the space S at least during temperature rise, the heat insulating performance can be improved and a temperature drop due to heat escape from the heater unit 200 can be suppressed. On the other hand, it has been confirmed that by supplying a gas with high thermal conductivity to the space S when lowering the temperature inside the furnace, heat escape from the heater unit 200 can be promoted, thereby significantly shortening the temperature drop time. [Explanation of symbols]

[0095] 1. Substrate processing equipment 2 heaters 20 Reaction tube 41 PCB 70 Multi-layer section 72 Insulator 73 Inner insulation section 74 Outer insulation section 200, 700 heater unit 500 Controller

Claims

1. a heat insulating section having a heat generating section for heating the inside of the reaction tube; a multi-layer section provided outside the heat insulating section and having a space therein, The multilayer section has a plurality of heat insulators along a direction from the heat insulator toward the outside, and spaces are formed between the heat insulators, and the heat radiation amount of the multilayer section can be changed depending on the thermal conductivity in the spaces and the thermal emissivity of the heat insulators, and the heat insulators are selected depending on the process performed in the reaction tube. Heater unit.

2. 2. The heater unit according to claim 1, wherein the width of the space is set so that the number of the heat insulators provided in the multilayer section is five or more.

3. 2. The heater unit according to claim 1, wherein the heat insulator is a metal or an alloy.

4. 2. The heater unit according to claim 1, wherein the thermal emissivity of the heat insulator is 0.02 or more and 0.1 or less.

5. 2. The heater unit according to claim 1, wherein the melting point of the heat insulator is equal to or higher than the temperature at which the heat is processed in the reaction tube.

6. Furthermore, an exhaust device is provided so as to be able to exhaust the space, 2. The heater unit according to claim 1, wherein the space can be depressurized to a vacuum by the exhaust device so as to suppress heat dissipation by conductive heat.

7. 7. The heater unit according to claim 6, wherein the exhaust device is configured to be able to reduce the pressure in the space to less than 200 Pa.

8. Furthermore, a gas supply unit is provided so as to be able to supply a predetermined gas to the space, 2. The heater unit according to claim 1, wherein the gas supply unit is configured to be able to supply a predetermined gas to the space formed between the heat insulators.

9. 9. The heater unit according to claim 8, wherein the predetermined gas has a thermal conductivity higher than that of air.

10. 10. The heater unit according to claim 9, wherein the predetermined gas is a rare gas.

11. Furthermore, an exhaust device is provided so as to be able to exhaust the space, 10. The heater unit according to claim 9, wherein the exhaust device is configured to be able to adjust the pressure in the space to 200 Pa or higher.

12. further comprising a ceiling portion provided above the reaction tube, 2. The heater unit according to claim 1, wherein the width of the space and the thickness of the heat insulator are set so that the combined outer diameter of the heat insulator and the multilayer section is approximately the same as the outer diameter of the ceiling section.

13. 2. The heater unit according to claim 1, wherein the thickness of the heat insulating portion is greater than the thickness of the heat insulator of the multi-layer portion and greater than the width of the space provided in the multi-layer portion.

14. The heater unit according to claim 1 , wherein the multilayer portion is configured to sandwich a heat insulating material in the space.

15. 2. The heater unit according to claim 1, wherein the heat insulating portion and the multi-layer portion are divisible into a plurality of regions.

16. A heat insulating section having a heat generating section for heating the inside of the reaction tube; a multi-layer section provided outside the heat insulating section and having a space therein, the multilayer section has a plurality of thermal insulators along a direction from the thermal insulator toward the outside, and spaces are formed between the thermal insulators, and the amount of heat dissipation from the multilayer section can be changed depending on the thermal conductivity in the spaces and the thermal emissivity of the thermal insulators; The heater unit is configured so that the pressure in the space can be individually adjusted to a value between several Pa and less than 200 Pa for the plurality of regions by an exhaust device that is provided so as to be able to exhaust the space.

17. a heat insulating section having a heat generating section for heating the inside of the reaction tube; A multilayer structure having a multilayer part provided outside the heat insulating part and having a space therein, The multilayer section has a plurality of heat insulators along a direction from the heat insulator toward the outside, and spaces are formed between the heat insulators, and the heat radiation amount of the multilayer section can be changed depending on the thermal conductivity in the spaces and the thermal emissivity of the heat insulators, and the heat insulators are selected depending on the process performed in the reaction tube. Multilayer structure.

18. A heat insulating section having a heat generating section for heating the inside of the reaction tube; A multilayer structure having a multilayer part provided outside the heat insulating part and having a space therein, the multilayer section has a plurality of thermal insulators along a direction from the thermal insulator toward the outside, and spaces are formed between the thermal insulators, and the amount of heat dissipation from the multilayer section can be changed depending on the thermal conductivity in the spaces and the thermal emissivity of the thermal insulators; A multilayer structure in which the pressure in the space can be individually adjusted to a range of several Pa or more and less than 200 Pa for a plurality of regions by an exhaust device that is provided so as to be able to exhaust the space.

19. a heat insulating section having a heat generating section for heating the inside of the reaction tube; a multilayer section provided on the outside of the heat insulating section and having a space therein; The multilayer section has a plurality of heat insulators arranged in a direction from the heat insulator toward the outside, and spaces are formed between the heat insulators, and the heat radiation amount of the multilayer section can be changed depending on the thermal conductivity in the spaces and the thermal emissivity of the heat insulators, and the heat insulators are provided with heater units selected depending on the process performed in the reaction tube. Processing equipment.

20. A heat insulating section having a heat generating section for heating the inside of the reaction tube; a multilayer section provided on the outside of the heat insulating section and having a space therein; the multilayer section has a plurality of thermal insulators along a direction from the thermal insulator toward the outside, and spaces are formed between the thermal insulators, and the amount of heat dissipation from the multilayer section can be changed depending on the thermal conductivity in the spaces and the thermal emissivity of the thermal insulators; The space is provided with a heater unit configured to be able to individually adjust the pressure of the space to a range of several Pa or more and less than 200 Pa for a plurality of regions by an exhaust device that is provided to be able to exhaust the space. Processing equipment.

21. a heat insulating section having a heat generating section for heating the inside of the reaction tube; a multilayer section provided on the outside of the heat insulating section and having a space therein; A method for manufacturing a semiconductor device, wherein the multilayer section has a plurality of insulators along a direction from the insulating section toward the outside, and spaces are formed between each insulator, and the amount of heat dissipation of the multilayer section can be changed depending on the thermal conductivity in the space and the thermal emissivity of the insulators, and the insulators are heater units selected depending on the process being performed in the reaction tube, and heat the substrate in the reaction tube.

22. A heat insulating section having a heat generating section for heating the inside of the reaction tube; a multilayer section provided on the outside of the heat insulating section and having a space therein; the multilayer section has a plurality of thermal insulators along a direction from the thermal insulator toward the outside, and spaces are formed between the thermal insulators, and the amount of heat dissipation from the multilayer section can be changed depending on the thermal conductivity in the spaces and the thermal emissivity of the thermal insulators; The substrate in the reaction tube is heated by a heater unit configured to be able to individually adjust the pressure of the space to a range of several Pa or more and less than 200 Pa for a plurality of regions by an exhaust device that is installed so as to be able to exhaust the space. A method for manufacturing a semiconductor device.

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