Temperature measurement assembly, substrate processing device, substrate processing method, and manufacturing method for semiconductor device

Abstract

To provide a technique of being able to measure temperature stably for a long time under a high-temperature environment.SOLUTION: A temperature measurement assembly includes a gas supply tube 34 that internally has a flow channel where gas flows, a temperature sensor 33 that is disposed outside the gas supply tube and includes a measurement unit to measure temperature, and a protection tube 32 in which the gas supply tube and the temperature sensor are disposed. An exhaust nozzle 34a of the gas supply tube to exhaust the gas into the protection tube is disposed at a higher position than the temperature sensor. The gas goes down in a gap 39 between an outer wall 37 of the temperature sensor and an inner wall of the protection tube.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a temperature measurement assembly, a substrate processing apparatus, a substrate processing method, and a method for manufacturing a semiconductor device. [Background technology]

[0002] In a method for manufacturing a semiconductor device, a vertical substrate processing apparatus may be used as an apparatus for forming an oxide film or a metal film on a substrate (hereinafter referred to as a wafer). When forming a predetermined film on a wafer, the inside of the processing chamber is heated to a predetermined temperature while supplying a processing gas into the processing chamber. In order to maintain the inside of the processing chamber at the predetermined temperature, a temperature sensor, such as a thermocouple, for detecting the temperature is provided in the processing chamber.

[0003] One example of a thermocouple that can be used in high-temperature environments is the WRe (tungsten-rhenium) sheathed thermocouple. The WRe thermocouple can be used at high temperatures, but cannot be used in an oxidizing atmosphere. A sheathed thermocouple is constructed by inserting a thermocouple and an insulator into a metal sheath tube, filling the sheath tube with an inert gas, and sealing the seal end to isolate the thermocouple from the oxidizing atmosphere. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] WO2012 / 115170 publication [Patent Document 2] JP 2013-207057 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a high-temperature environment, substances such as oxygen that deteriorate the sheath tube are generated from the materials constituting the processing chamber and the deposited films. When the sheath tube deteriorates, oxygen and the like may reach the inside of the sheath tube. As a result, the state in which the inside of the sheath tube is completely filled with an inert atmosphere is destroyed, which in turn deteriorates the thermocouple, causing a decrease in the electromotive force of the thermocouple or a break in the thermocouple, making it impossible to measure the temperature correctly. In particular, when the sheath tube is covered with a protective tube, there is a possibility that it may be exposed for a long period of time to the gas released from the protective tube that remains inside the protective tube. In addition, the evaporation and gas release from the sheath tube itself may also cause deterioration of the protective tube and contamination of the processing chamber.

[0006] The present disclosure provides a technique that enables stable temperature measurement for a long period of time in a high-temperature environment. [Means for solving the problem]

[0007] According to one aspect of the present disclosure, there is provided a technology comprising a gas supply pipe having a flow path therein through which gas flows, a temperature sensor disposed outside the gas supply pipe and having a measuring unit for measuring temperature, and a protective tube in which the gas supply pipe and the temperature sensor are disposed, wherein an outlet of the gas supply pipe for spraying the gas into the protective tube is disposed at a position higher than the temperature sensor, and the gas is configured to flow through a gap between an outer wall of the temperature sensor and an inner wall of the protective tube. Effect of the Invention

[0008] According to the present disclosure, it is possible to stably measure temperature for a long period of time in a high-temperature environment. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a vertical cross-sectional view showing an example of a processing furnace according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a cross-sectional view of a temperature measurement assembly according to an embodiment of the present disclosure. [Diagram 3] 1 is an enlarged longitudinal cross-sectional view showing a temperature measurement assembly and a mounting portion according to an embodiment of the present disclosure; [Figure 4]1 is an enlarged longitudinal cross-sectional view showing a tip portion of a temperature measuring assembly according to an embodiment of the present disclosure. [Diagram 5] 1 is a flowchart illustrating a substrate processing method according to an embodiment of the present disclosure. [Figure 6] FIG. 1A is a vertical cross-sectional view showing a modified example of a temperature measuring assembly according to an embodiment of the present disclosure, and FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 5. Note that all drawings used in the following description are schematic, and the dimensional relationships, ratios, etc. of the elements shown in the drawings do not necessarily match those of reality. Furthermore, the dimensional relationships, ratios, etc. of the elements do not necessarily match between multiple drawings.

[0011] First, an embodiment according to the present disclosure will be described with reference to Fig. 1. Fig. 1 shows a vertical cross-sectional view of a processing furnace 2 in a substrate processing apparatus 1 according to this embodiment. Note that Figs. 2 to 4 are configured similarly to the substrate processing apparatus 1 shown in Fig. 1, and therefore elements substantially the same as those described in Fig. 1 are denoted by the same reference numerals and description thereof will be omitted.

[0012] The substrate processing apparatus 1 according to the present embodiment is configured as an apparatus for performing annealing on a plurality of SiC substrates aligned in the vertical direction, that is, a so-called batch-type vertical SiC annealing apparatus. By configuring it as a batch-type processing apparatus, it becomes possible to process a large number of substrates at once, thereby improving productivity.

[0013] The substrate processing apparatus 1 has a similar configuration to that shown in FIG. 1 of Patent Document 1. The substrate processing apparatus 1 has a processing furnace 2, and a boat 3 serving as a substrate holder is removably inserted into the processing furnace 2. The boat 3 is made of a heat-resistant material such as carbon graphite or SiC. The boat 3 is configured to hold a plurality of wafers 4 serving as substrates made of SiC or the like, stacked vertically in a horizontal position and aligned with their centers aligned. In addition, a boat insulation part 5 serving as a heat insulation part, made of a heat-resistant material such as quartz or SiC, is disposed at the bottom of the boat 3. The boat insulation part 5 is configured to support the boat 3 from below and to make it difficult for heat from an induction target 6 to be described later to be transmitted to the lower side of the processing furnace 2. The boat 3 loaded with a plurality of wafers 4 is loaded into the processing furnace 2, whereby heat processing is performed.

[0014] Next, the configuration of the processing furnace 2 included in the substrate processing apparatus 1 will be described.

[0015] 1, the processing furnace 2 is made of a heat-resistant material such as quartz or SiC, and includes a reaction tube 7 formed in a cylindrical shape with a closed upper end and an open lower end. A reaction chamber 8 serving as a processing chamber is formed in a hollow cylindrical portion of the reaction tube 7. The reaction chamber 8 is configured to accommodate the boat 3 described above holding wafers 4 serving as substrates made of SiC or the like.

[0016] A manifold 11 is disposed concentrically with the reaction tube 7 below the reaction tube 7. The manifold 11 is made of, for example, stainless steel, and is formed in a cylindrical shape with an open upper end and a lower end. The manifold 11 is provided so as to support the reaction tube 7 from below. An O-ring (not shown) is provided as a sealing member between the manifold 11 and the reaction tube 7. The manifold 11 is supported by a holder (not shown), so that the reaction tube 7 is installed vertically. The reaction tube 7 and the manifold 11 form a reaction vessel.

[0017] The processing furnace 2 includes an induction target 6 as a heated object to be heated by induction heating, and an induction coil 12 as an induction heating unit, i.e., a magnetic field generating unit. The induction target 6 is formed in a cylindrical shape from a conductive heat-resistant material such as carbon, and is provided so as to surround the boat 3 contained in the reaction chamber 8, i.e., to surround the storage area of ​​the wafers 4. The induction target 6 is formed in a cylindrical shape with upper and lower ends open, or a cylindrical shape with a closed upper end and an open lower end. The induction coil 12 is supported by a coil support 12a made of an insulating heat-resistant material, and is provided so as to surround the outer periphery of the reaction tube 7. The induction coil 12 is configured to be supplied with AC power of, for example, 10 to 450 kHz and 10 to 200 kW from an AC power source 13. An AC magnetic field generated by passing an AC current through the induction coil 12 causes an induced current, i.e., an eddy current, to flow through the induction target 6, and the induction target 6 is heated by Joule heat. When the induction target 6 generates heat, the wafers 4 held in the boat 3 are heated to a predetermined processing temperature, for example, 1500° C. to 2000° C., by the radiant heat emitted from the induction target 6. In order to prevent thermal damage, it is preferable to maintain the temperature of the components below the processing furnace 2 at, for example, 200° C. or lower.

[0018] Between the reaction tube 7 and the induction target 6, a heat insulator 14 made of, for example, carbon felt that is not easily induced is provided. The heat insulator 14 is formed in a cylindrical shape with a closed upper end and an open lower end. By providing the heat insulator 14, it is possible to suppress the transfer of heat from the induction target 6 to the reaction tube 7 or to the outside of the reaction tube 7.

[0019] Between the boat 3 holding the wafers 4 and the induced member 6, a temperature measurement assembly 15 for detecting the processing temperature is provided. The temperature measurement assembly 15 penetrates the manifold 11 and extends vertically above the upper end of the boat 3. The temperature measurement assembly 15 is electrically connected to a temperature control unit (not shown). The temperature control unit adjusts the power supply from the AC power source 13 to the induction coil 12 based on the temperature information detected by the temperature measurement assembly 15, thereby controlling the processing temperature of the wafers 4 to a desired temperature. The induced member 6, the induction coil 12, the AC power source 13, and the temperature measurement assembly 15 mainly constitute a heating unit according to this embodiment.

[0020] Additionally, an outer heat insulating wall 16, for example of a water-cooled structure, which suppresses the transfer of heat from within the reaction chamber 8 to the outside, is provided outside the induction coil 12 so as to surround the reaction chamber 8. Furthermore, a magnetic shield 17 is provided outside the outer heat insulating wall 16 to prevent the magnetic field generated by the induction coil 12 from leaking to the outside. The outer heat insulating wall 16 and the magnetic shield 17 may be configured as an integral structure.

[0021] The process furnace 2 is provided with a first gas nozzle 18 having a first gas supply port 18a. The first gas nozzle 18 is disposed inside the induction target 6, vertically between the accommodation region of the wafer 4 and the induction target 6. The first gas nozzle 18 is made of a heat-resistant material such as carbon graphite. The first gas nozzle 18 is provided with the first gas supply port 18a at its upper end (tip). The downstream end of a first gas supply pipe 19 is connected to the upstream end of the first gas nozzle 18. The first gas supply pipe 19 is provided so as to penetrate the manifold 11. The upstream end of the first gas supply pipe 19 is connected to a gas supply unit 21.

[0022] A second gas supply pipe 22 is disposed in the vertical direction outside the induction target 6, between the heat insulator 14 and the reaction tube 7. A second gas supply port 23 is provided at the downstream end of the second gas supply pipe 22. The second gas supply pipe 22 is provided so as to penetrate the manifold 11. A gas supply unit 21 is connected to the upstream end of the second gas supply pipe 22.

[0023] A first exhaust port 24 is provided on the side wall of the manifold 11 facing the first gas supply port 18a at the lower side of the boat insulation part 5, i.e., the area for accommodating the wafers 4. A second exhaust port 25 is provided on the wall of the manifold 11 between the insulation body 14 and the reaction tube 7 on which the reaction tube 7 is placed. The first exhaust port 24 and the second exhaust port 25 are connected to the upstream ends of the branched exhaust pipe 26. The exhaust pipe 26 is provided with a pressure sensor 27 as a pressure detector, an APC (Auto Pressure Controller) valve 28 as a pressure regulator, and a vacuum pump 29 as a vacuum exhaust device, in this order from the upstream side. The pressure sensor 27, the APC valve 28, and the vacuum pump 29 are electrically connected to a pressure control part (not shown). The pressure control part feedback-controls the opening of the APC valve 28 based on pressure information measured by the pressure sensor 27, thereby controlling the pressure in the reaction chamber 8 to a predetermined pressure at a predetermined timing.

[0024] By providing the first exhaust port 24 as described above, the gas supplied from the first gas supply port 18a into the reaction chamber 8, i.e., the process gas, flows downward inside the reaction chamber 8, i.e., inside the induction target 6, through the region where the boat insulation part 5 is provided, and is exhausted from the first exhaust port 24. At this time, the entire wafer 4 is efficiently and uniformly exposed to the gas.

[0025] Moreover, by providing the second exhaust port 25 as described above, the inert gas such as nitrogen supplied from the second gas supply port 23 into the reaction chamber 8 acts as a purge gas, flows between the reaction tube 7 and the insulator 14, and is exhausted from the second exhaust port 25. This suppresses the intrusion of the process gas into the gap between the reaction tube 7 and the insulator 14, and prevents unwanted products and the like from adhering to the surfaces thereof.

[0026] Furthermore, the boat 3 can be carried into the reaction chamber 8, i.e., boat loading, and carried out, i.e., boat unloading, by a lifting mechanism (not shown). By carrying the boat 3 into the reaction chamber 8, the opening of the processing furnace 2, i.e., the furnace mouth, is air-tightly closed by a seal cap 31 via a sealing member such as an O-ring. A boat rotation mechanism 30 supporting the boat insulation part 5 penetrates the center of the seal cap 31, and the boat 3 can be rotated by the boat rotation mechanism 30.

[0027] Next, the temperature measurement assembly 15 will be described in detail with reference to Figures 2 to 4. The temperature measurement assembly 15 is installed vertically in the reaction tube 8, but is illustrated in Figures 2 and 4 as extending horizontally.

[0028] The temperature measurement assembly 15 has a protective tube 32, a sheathed thermocouple 33 as a temperature sensor inserted into the protective tube 32, a gas supply pipe 34, an exhaust pipe 35, and a sealing portion 36 that seals the protective tube 32. The sheathed thermocouple 33 can be disposed at a position farther from the axis (central axis) of the protective tube 32 than the gas supply pipe 34 is.

[0029] The protective tube 32 has a cylindrical shape with a closed upper end and an open lower end. The material of the protective tube is appropriately selected from various high-temperature ceramics and metal materials according to conditions such as the processing temperature, etc., including oxides such as Al2O3 and MgO, carbides such as TaC, TiC, and SiC, and nitrides such as BN and AlN.

[0030] The sheathed thermocouple 33 is inserted into the protective tube 32 in parallel with the axis of the protective tube 32 so as to penetrate the sealing portion 36. The sheathed thermocouple 33 has a sheath tube 37 and a thermocouple (Thermo Couple: TC) 38 as a measuring portion for measuring the temperature arranged in the sheath tube 37. The sheath tube 37 has a cylindrical shape with a closed upper end and an open lower end. The sheath tube 37 is made of a metal such as Ta or Mo. The sheath tube 37 is filled with an insulating powder such as magnesium oxide so that the thermocouple 38 arranged inside does not move easily. Furthermore, the sheath tube 37 is filled with an inert gas, and the thermocouple cable outlet of the sheath tube 37 is sealed with glass or the like, and the inside of the sheath tube 37 is completely purged with the inert gas and sealed.

[0031] The gas supply pipe 34 is inserted into the protective pipe 32 parallel to the axis of the protective pipe 32 so as to penetrate the sealing portion 36, and extends to the vicinity of the upper end (tip) inner wall of the protective pipe 32. Therefore, a space (internal space) 32a of a predetermined size is formed between the upper end of the gas supply pipe 34 and the upper end of the inner wall of the protective pipe 32. The gas supply pipe 34 has a flow path formed inside and a nozzle 34a formed at the tip, and is configured to be able to supply inert gas such as argon gas (Ar gas) or nitrogen gas (N2 gas) upward to the space 32a in the protective pipe 32 through the nozzle 34a. That is, the space 32a is formed on the upper side inside the gas supply pipe 34, that is, in the gas ejection direction. The space 32a is provided to change the flow direction of the inert gas ejected from the nozzle 34a downward as smoothly as possible, and no solid object is placed therein.

[0032] As shown in Fig. 4, the upper end (tip) of the gas supply pipe 34 extends above the upper end (tip) of the sheathed thermocouple 33, and the lower end is connected to an inert gas supply device (not shown). The dimension A from the upper end of the gas supply pipe 34 to the upper inner wall of the protective tube 32 is shorter than the dimension B from the upper end of the sheathed thermocouple 33 to the upper inner wall of the protective tube 32. Therefore, the sheathed thermocouple 33 and the gas supply pipe 34 are respectively arranged so that the position of the upper end of the gas supply pipe 34 is higher than the upper end of the sheathed thermocouple 33. As a result, the discharged inert gas does not directly hit the sheathed thermocouple 33, but rather is heated to the same temperature as the protective tube 32 while flowing along the inner wall of the protective tube 32 before coming into contact with the sheathed thermocouple 33.

[0033] The exhaust pipe 35 is inserted into the protective pipe 32 parallel to the axis of the protective pipe 32 so as to penetrate the sealing portion 36. The upper end (tip) of the exhaust pipe 35 is located near the sealing portion 36 and is configured to be able to exhaust the gas inside the protective pipe 32. That is, the exhaust pipe 35, which communicates the atmosphere inside the protective pipe 32 with the outside atmosphere, opens near the sealing portion 36 at the lower part of the protective pipe 32. In addition, the diameter of the exhaust pipe 35 is larger than the diameter of the gas supply pipe 34. This makes it possible to suppress an increase in pressure inside the protective pipe 32.

[0034] The sealing portion 36 is, for example, a heat-resistant adhesive or a heat-resistant resin, and is configured as a sealing material that airtightly seals the opening, i.e., the lower end, of the protective tube 32. The sealing portion 36 isolates the atmosphere inside the protective tube 32, except for the exhaust pipe 35, from the outside atmosphere.

[0035] The inert gas supplied to the gas supply pipe 34 is sprayed from the nozzle 34a into the space 32a inside the protective tube 32, deflected along the upper end of the inner wall of the protective tube 32, descending through the gap 39 between the outer wall of the sheathed thermocouple 33 and the inner wall of the protective tube 32, and exhausted to the outside via the exhaust pipe 35.

[0036] 3 shows an enlarged cross-sectional view of the periphery of the mounting portion of the temperature measuring assembly 15. The manifold 11 has an annular flange portion 11a at the upper end thereof, which expands outward in the circumferential direction, and the reaction tube 7 is placed on the flange portion 11a. An O-ring 41 is provided between the reaction tube 7 and the flange portion 11a, and the O-ring 41 ensures airtightness between the reaction tube 7 and the flange portion 11a.

[0037] Further, the flange portion 11a is formed with a TC port 42. The TC port 42 has a cylindrical shape extending downward in parallel with the axis of the reaction tube 7, and has a threaded portion 42a formed at the lower end portion.

[0038] The temperature measuring assembly 15 is held by a TC holder 43. The TC holder 43 has a case portion 40, a cable outlet hole 48 serving as an exhaust portion, a terminal screw 51, and a sleeve 53 serving as a vacuum joint.

[0039] The case portion 40 has a generally cylindrical shape, and the inside diameter is larger than the outside diameter of the protective tube 32. A cylindrical recess 44 is formed in the middle of the outer periphery of the case portion 40, and a cap nut 45 is loosely fitted into the recess 44 so as not to fall off, and the cap nut 45 is able to slide up and down between the upper and lower ends of the recess 44. In addition, an annular flange portion 40a extending toward the outer periphery is formed at the upper end of the recess 44.

[0040] Inside the case 40, an inner flange 46 is formed as an adhesive part extending toward the center, and the inner flange 46 forms a hole 47 smaller than the inner diameter of the case 40. The diameter of the hole 47 is larger than the inner diameter of the protective tube 32 and smaller than the outer diameter of the protective tube 32. Therefore, when the case 40 holds the temperature measurement assembly 15, the lower surface of the protective tube 32 abuts against the upper surface of the inner flange 46. The protective tube 32 and the inner flange 46 are bonded with an adhesive, and the protective tube 32 and the case 40 are integrated. The sheathed thermocouple 33, the gas supply pipe 34, and the exhaust pipe 35, which penetrate the sealing part 36, extend downward through the hole 47.

[0041] A cable outlet hole 48 is formed in the peripheral wall of the case portion 40 below the inner flange portion 46. A thermocouple cable 49 serving as an element wire of a temperature sensor extends from the lower end of the sheathed thermocouple 33 and is drawn out of the case portion 40 through the cable outlet hole 48. The cable outlet hole 48 also functions as an exhaust port for discharging the inert gas discharged from the exhaust pipe 35 to the outside.

[0042] A flat surface 40b is formed on the outer wall of the case 40, which is parallel to the longitudinal direction of the protective tube 32, and a terminal screw 51 is provided on the flat surface 40b. The terminal screw 51 is provided on the flat surface 40b, which makes it easy to attach and detach the terminal screw 51. The terminal screw 51 functions as an exposed terminal electrically connected to the sheathed thermocouple 33. The end of the thermocouple cable 49 extending from the cable outlet hole 48 is detachable from the terminal screw 51. In addition, a measuring instrument (not shown) capable of receiving an electrical signal from the thermocouple 38 can be connected to the terminal screw 51 via a cable (not shown). The terminal screw 51 and the cable connected to the measuring instrument function as a connector electrically connected to the sheathed thermocouple 33.

[0043] The lower end opening of the case part 40 is closed by a holder cap 52 as a lid. The holder cap 52 has a hole through which the gas supply pipe 34 passes, and the holder cap 52 closes the case part 40 in a state in which the gas supply pipe 34 passes through it. Therefore, the holder cap 52 also functions as a support part that supports a load in a direction perpendicular to the axial direction of the gas supply pipe 34. In addition, one end of the exhaust pipe 35 that passes through the sealing part 36 opens into the case part 40 below the inner flange part 46 so as to be fluidically connected thereto. Furthermore, the inside of the case part 40 is purged by the inert gas exhausted from the inside of the protective pipe 32 by the exhaust pipe 35. The inert gas that has purged the inside of the case part 40 is exhausted from the cable outlet hole 48.

[0044] A cylindrical sleeve 53 is provided on the upper side of the case part 40. The protective tube 32 is inserted into the sleeve 53, and the lower end of the sleeve 53 abuts against the upper end of the case part 40. The sleeve 53 also has a large diameter part 53a and a small diameter part 53b having a smaller diameter than the large diameter part 53a. The outer diameter of the large diameter part 53a is larger than the inner diameter of the TC port 42 and smaller than the outer diameter of the TC port 42. The outer diameter of the small diameter part 53b is smaller than the inner diameter of the TC port 42, so that the small diameter part 53b can be inserted into the TC port 42. Furthermore, an O-ring 54 is provided as a first airtight member around the entire circumference on the inner wall of the large diameter part 53a, and an O-ring 55 is provided as a second airtight member around the entire circumference on the upper end of the large diameter part 53a.

[0045] When the protective tube 32 is inserted into the sleeve 53, the O-ring 54 is pressed by the outer wall of the protective tube 32, ensuring airtightness between the sleeve 53 and the protective tube 32. When the small diameter portion 53b is inserted into the TC port 42, the O-ring 55 is pressed between the large diameter portion 53a and the lower end of the TC port 42, ensuring airtightness between the sleeve 53 and the inside of the TC port 42. Therefore, the O-rings 54 and the O-ring 55 ensure airtightness inside the TC port 42, i.e., inside the reaction chamber 8, and are configured to prevent the atmosphere inside the reaction chamber 8 from flowing out from the TC port 42.

[0046] When the temperature measuring assembly 15 is attached to the processing furnace 2, the temperature measuring assembly 15 is held by the case part 40, and the protective tube 32 is inserted into the sleeve 53, and the small diameter part 53b of the protective tube 32 and the sleeve 53 are inserted into the TC port 42 from below. The cap nut 45 is screwed onto the threaded part 42a formed on the outer circumferential wall of the TC port 42. By screwing the cap nut 45, the flange part 40a is pulled upward, i.e., toward the sleeve 53, and the sleeve 53 abutting against the flange part 40a is pressed against the TC port 42. By pressing the sleeve 53, the upper surface of the large diameter part 53a is pressed against the lower surface of the TC port 42, and the TC port 42 is airtightly closed via the O-ring 55. The flange part 40a and the cap nut 45 function as an engagement part for engaging with the sleeve 53.

[0047] Next, substrate processing using the above-mentioned substrate processing apparatus 1 will be described with reference to the flowchart of Fig. 5. Here, an example will be described in which argon (Ar) gas is supplied as a processing gas into the reaction chamber 8, and an annealing process is performed to remove oxygen on the wafer 4. In this specification, the processing temperature means the temperature of the wafer 4 or the temperature of the reaction chamber 8, and the processing pressure means the pressure inside the reaction chamber 8. In the following description, the operation of each part constituting the substrate processing apparatus 1 is controlled by a controller (not shown).

[0048] The explanation will be given from the state where the seal cap 31 is lowered by a lifting mechanism (not shown) and the boat 3 is carried out from the reaction tube 7, that is, the boat is unloaded and there are no wafers 4 in the boat 3. (Wafer charge and boat load) When a FOUP containing wafers 4 is loaded into the substrate processing apparatus 1, the wafers 4 are transported to the boat 3 by a transfer machine (not shown) (STEP: 01). When multiple wafers 4 are loaded into the boat 3, i.e., wafer charging, the seal cap 31 is raised by a lifting mechanism (not shown), and the boat 3 is carried inside the induction target 6 in the reaction chamber 8, i.e., boat loading, and the lower opening of the reaction tube 7 is airtightly closed (sealed) by the seal cap 31 (STEP: 02).

[0049] (Pressure and temperature regulation) The reaction chamber 8 is evacuated, that is, decompressed, by the vacuum pump 29. The atmosphere in the reaction chamber 8 flows linearly or approximately linearly through the exhaust pipe 26 and is exhausted through the vacuum pump 29. Once the pressure in the reaction chamber 8 is evacuated, Ar gas is supplied into the reaction chamber 8. The Ar gas is controlled to a predetermined flow rate by the gas supply unit 21, and is supplied into the reaction chamber 8 from the tip of the first gas nozzle 18 through the first gas supply pipe 19 and the first gas nozzle 18. In parallel with the supply of Ar gas, that is, with the seal cap 31 closing the opening of the manifold 11, the gas supply unit 21 supplies a purge gas, the flow rate of which is controlled to a desired flow rate, from the second gas supply port 23 through the second gas supply pipe 22 to between the reaction tube 7 and the heat insulator 14. After being ejected upward, the purge gas diffuses in the circumferential direction along the ceiling, descends along the circumferential surface, and is exhausted to the outside of the reaction chamber 8 through the second exhaust port 25 and the exhaust pipe 26. The pressure inside the reaction chamber 8 is measured by a pressure sensor 27, and based on this measured pressure information, the APC valve 28 is feedback-controlled to adjust the pressure to a predetermined pressure (degree of vacuum).

[0050] A predetermined AC power is supplied from the AC power source 13 to the induction coil 12 so that the wafers 4 in the reaction chamber 8 reach a predetermined temperature, and an induced current is passed through the induced member 6 to raise the temperature of the induced member 6, which then heats the wafers 4 from the surroundings. The wafers 4 can be heated efficiently by heating through induction heating. At this time, the current flow to the induction coil 12 is feedback-controlled based on temperature information detected by the sheathed thermocouple 33 so that the entire wafers 4 loaded in the boat 3 have a predetermined temperature distribution. Also, the boat rotation mechanism 30 starts to rotate the boat 3 and the wafers 4.

[0051] In parallel with the energization of the induction coil 12, an inert gas is supplied into the protective tube 32 via the gas supply pipe 34. The inert gas is constantly supplied into the protective tube 32 during the substrate processing, for example. Alternatively, the supply of the inert gas into the protective tube 32 may start when the temperature detected by the sheathed thermocouple 33 becomes higher than the outside air temperature.

[0052] The supply of inert gas creates an inert gas atmosphere inside protective tube 32, which prevents deterioration of sheath tube 37 and maintains the inert gas atmosphere inside sheath tube 37, thereby preventing oxidation of sheathed thermocouple 33. Furthermore, by continuously supplying inert gas from gas supply pipe 34 and exhausting inert gas from exhaust pipe 35, the atmosphere inside protective tube 32 is constantly replaced with new inert gas, and the inert gas atmosphere can be maintained.

[0053] (Substrate processing) The wafer 4 is heated in an Ar atmosphere at a predetermined temperature for a predetermined time, thereby activating the ion-implanted impurities and removing oxygen from the surface, thereby producing an annealed wafer (STEP: 03).

[0054] (Boat unloading and wafer discharging) After the annealed wafers are produced, the power supply to the induction coil 12 is cut off, and the wafers 4 are cooled until their temperature drops to a predetermined temperature. After the wafers 4 are cooled, the APC valve 28 is closed, and the pressure inside the reaction chamber 8 is returned to atmospheric pressure. Then, the seal cap 31 is lowered by a lifting mechanism (not shown), and the boat 3 is removed from the reaction tube 7, i.e., the boat is unloaded. (STEP: 04).

[0055] After the boat 3 is removed, that is, while the seal cap 31 is not closing the opening of the reaction chamber 8, a cooling process is performed on the wafers 4 and the boat insulation part 5 (STEP: 05).

[0056] When the wafers 4 and the boat insulation section 5 have been cooled to a predetermined temperature, the processed wafers 4 loaded into the boat 3 are stored in the FOUP by a transfer machine (not shown), and the FOUP is removed from the substrate processing apparatus 1 (STEP: 06), completing the substrate processing.

[0057] The processing conditions for Ar annealing the wafer 4 are, for example, as follows. Processing temperature (wafer temperature): 1500℃~1900℃, Processing pressure (pressure inside the processing chamber): 1 Pa to normal pressure, Ar gas: 1sccm to 5SLM, N2 gas: 1sccm~5SLM, By setting each processing condition to a value within each range, the film formation process can be carried out appropriately. Note that the expression of a numerical range such as "1500°C to 1900°C" above means that the lower limit and the upper limit are included in the range. For example, "1500°C to 1900°C" means "1500°C or more and 1900°C or less". The same applies to other numerical ranges.

[0058] According to this aspect, one or more of the following effects can be obtained.

[0059] In this embodiment, the temperature measuring assembly 15 provided in the reaction chamber 8 includes the protective tube 32, the sheathed thermocouple 33 inserted in the protective tube 32, and the gas supply tube 34, so that the inert gas is continuously supplied from the gas supply tube 34 into the protective tube 32 to continuously replace the inside of the protective tube 32 with the inert gas, thereby maintaining an inert gas atmosphere in the protective tube 32. Even if oxygen or impurities volatilize from the protective tube 32 itself, they can be discharged by the constantly supplied inert gas, so that deterioration of the sheathed thermocouple 33 can be prevented, the life of the sheathed thermocouple 33 can be extended, and the temperature in the reaction chamber 8 can be stably measured for a long time.

[0060] Furthermore, since heat transfer within the reaction chamber 8 where the temperature reaches 1500°C or higher is dominated by heat radiation rather than heat conduction or heat transfer, responsiveness can be maintained even if the sheathed thermocouple 33 is not in contact with the protective tube 32.

[0061] Moreover, the sheathed thermocouple 33 is not directly exposed to the inside of the reaction chamber 8. Therefore, even if the sheathed thermocouple 33 deteriorates in a high-temperature environment, metal contamination of the wafer 4 can be suppressed.

[0062] In addition, since the upper end of the gas supply pipe 34 is located above the upper end of the sheathed thermocouple 33, the sheathed thermocouple 33 can be placed in the flow of inert gas from above, and the inert gas atmosphere can be more reliably created around the sheathed thermocouple 33, thereby further extending the life of the sheathed thermocouple 33. In addition, since the inert gas comes into contact with the sheathed thermocouple 33 after rising to a temperature equivalent to that of the protective tube 32, the measured temperature of the sheathed thermocouple 33 is not affected by the inert gas, and the temperature measurement accuracy can be improved.

[0063] Furthermore, since the temperature measuring assembly 15 is held by the case portion 40 and the sealing portion 36 is not exposed to the outside, external forces acting on the sealing portion 36 can be suppressed, and damage to the sealing portion 36 can be prevented.

[0064] Moreover, the holder cap 52 closes the case portion 40 with the gas supply pipe 34 passing through, i.e., the holder cap 52 restrains the circumferential movement of the gas supply pipe 34. Therefore, even if an external force is applied to the gas supply pipe 34, the external force can be received by the holder cap 52, and damage to the sealing portion 36 can be prevented.

[0065] Furthermore, the protective tube 32 and the case portion 40 are bonded and integrated with an adhesive, so that the engaging portion with the sleeve 53, i.e., the flange portion 40a and the cap nut 45, and the connector portion, i.e., the thermocouple cable 49 and the terminal screw 51, are integrated together. This prevents damage to the thermocouple cable 49 due to pulling, and makes it easy to replace the thermocouple cable 49.

[0066] 6(A) and 6(B) show a modified example of this embodiment. In FIG. 6(A) and FIG. 6(B), the same reference numerals are used for the same parts as those in FIG. 1 to FIG. 4, and the description thereof will be omitted. In the modified example, the temperature measurement assembly 15 has three sheathed thermocouples 56, 57, and 58. The sheathed thermocouples 56, 57, and 58 and the exhaust pipe 35 are inserted along the inner wall of the protective pipe 32 at equal circumferential intervals, for example, at 90° intervals as shown in FIG. 6(B). The gas supply pipe 34 is inserted inside the sheathed thermocouples 56, 57, and 58 and the exhaust pipe 35, for example, along the axis of the protective pipe 32. Although not shown, the sheathed thermocouples 56, 57, and 58 each have a sheath pipe and a thermocouple as a measurement unit arranged in the sheath pipe, like the sheathed thermocouple 33.

[0067] In addition, cable outlet holes 48 (six in FIG. 6(A)) are formed in multiple locations on the peripheral wall of the case portion 40, and each of the thermocouple cables 59, 60, 61 of the sheathed thermocouples 56, 57, 58 extends to the outside from one of the cable outlet holes 48.

[0068] In this modified example, the inert gas ejected from the upper end of the gas supply pipe 34 diffuses toward the center or circumferential direction along the upper end of the inner wall of the protective pipe 32, descends along the inner wall of the protective pipe 32, passes through the exhaust pipe 35, and is exhausted from the cable outlet hole 48, in the same configuration as in the above-described embodiment.

[0069] In this modified example, the same effects as those of the above-mentioned embodiment can be obtained. Furthermore, by providing a plurality of sheathed thermocouples 56, 57, 58 along the inner wall of the protective tube 32, stable temperature measurement can be performed regardless of the rotational position when the temperature measurement assembly 15 is attached. [Explanation of symbols]

[0070] 15 Temperature Measurement Assembly 32 Protection tube 33 Sheathed thermocouple 34 Gas supply pipe 38 Thermocouple 39 Gap

Claims

1. a gas supply pipe having a flow path through which a gas flows, a temperature sensor having a measurement unit that is disposed outside the gas supply pipe and measures a temperature, and a protective pipe in which the gas supply pipe and the temperature sensor are disposed, A temperature measurement assembly, wherein the outlet of the gas supply pipe that ejects the gas into the protective tube is positioned at a position higher than the temperature sensor, and the gas is configured to flow down a gap between an outer wall of the temperature sensor and an inner wall of the protective tube.

2. 2. The temperature measuring assembly according to claim 1, further comprising a gas exhaust pipe for exhausting the gas from inside the protective tube, the diameter of the gas exhaust pipe being larger than the diameter of the gas supply pipe.

3. 2. The temperature measuring assembly according to claim 1, wherein the protective tube has an internal space in a direction in which the gas is ejected from the gas supply tube.

4. 2. The temperature measurement assembly according to claim 1, wherein the temperature sensor comprises a sheathed tube, and the measurement portion is disposed inside the sheathed tube.

5. 2. The temperature measuring assembly of claim 1, further comprising a holder having an adhesive portion that is adhered to a lower portion of the protective tube, a connector portion having an exposed terminal that electrically connects to the temperature sensor, and an exhaust portion that exhausts the gas.

6. The temperature measuring assembly according to claim 5 , wherein the holder further comprises an engagement portion that engages with a vacuum joint that maintains airtightness between the holder and the protective tube.

7. 5. The temperature measuring assembly according to claim 4, further comprising a gas exhaust pipe for exhausting the gas from inside the protective tube, the gas supply pipe, the sheath tube and the gas exhaust pipe being arranged extending longitudinally inside the protective tube, with a portion of each being exposed to the outside of the protective tube, and the gap between each of the gas supply pipe, the sheath tube and the gas exhaust pipe being sealed with a sealant between the lower portion of the protective tube and the gas supply pipe.

8. 6. The temperature measuring assembly according to claim 5, wherein the holder includes a case portion that houses an element wire of the temperature sensor, and the connector portion is formed in the case portion.

9. 9. The temperature measuring assembly according to claim 8, wherein the case portion has a flat portion parallel to a longitudinal direction of the protective tube, and the terminals are arranged on the flat portion.

10. One end of a gas exhaust pipe for exhausting the gas from inside the protective tube is open in the case portion so as to be fluidly communicated therewith, and the inside of the case portion is purged with the gas, 9. The temperature measuring assembly according to claim 8, wherein the case portion has a flat portion parallel to a longitudinal direction of the protective tube, and the terminals are arranged on the flat portion.

11. 2. The temperature measurement assembly according to claim 1, wherein the temperature sensor is disposed at a position farther from the central axis of the protective tube than the gas supply tube.

12. 7. The temperature measuring assembly according to claim 6, wherein the engaging portion has a flange portion that abuts against the vacuum fitting and a cap nut that is screwed into the holder during installation to pull the holder toward the vacuum fitting, and the cap nut is loosely fitted into the holder by the flange portion so that it cannot fall off.

13. 2. The temperature measuring assembly according to claim 1, wherein a wire of said temperature sensor is led out of said case through a hole provided in said case and connected to a terminal screw provided on the outside of said case.

14. 9. The temperature measuring assembly according to claim 8, further comprising a lid for closing a bottom opening of said case portion and supporting said gas supply pipe.

15. 5. The temperature measuring assembly according to claim 4, wherein a plurality of said temperature sensors are provided, each of said temperature sensors being separately housed in said sheath tube.

16. A processing vessel; a heating unit provided to surround the processing vessel; a cylindrical heating element that is disposed in the processing vessel, accommodates a substrate, and is heated by the heating unit; a cylindrical insulator disposed between the processing vessel and the heating element; a temperature measuring assembly disposed inside the heating element and extending in an axial direction of the heating element; The temperature measurement assembly includes a gas supply pipe having a flow path through which a gas flows, a temperature sensor that is disposed outside the gas supply pipe and has a measurement unit that measures a temperature, and a protective pipe in which the gas supply pipe and the temperature sensor are disposed, a gas supply pipe having an outlet for injecting the gas into the protective tube, the outlet being positioned higher than the temperature sensor, and the gas being configured to flow down a gap between an outer wall of the temperature sensor and an inner wall of the protective tube.

17. accommodating the substrate inside a cylindrical heating element disposed in a processing chamber; a heating unit provided to surround the processing vessel to heat the cylindrical heating element; and controlling the heating section based on a temperature measured by a temperature measuring assembly disposed inside the heating element and extending in an axial direction of the heating element; A substrate processing method in which the controlling process uses a temperature measurement assembly having a gas supply pipe having a flow path therein through which gas flows, a temperature sensor arranged outside the gas supply pipe and having a measurement unit for measuring temperature, and a protective tube in which the gas supply pipe and the temperature sensor are arranged, and the gas sprayed into the protective tube from an injection port of the gas supply pipe arranged at a position higher than the temperature sensor descends in a gap between the outer wall of the temperature sensor and the inner wall of the protective tube.

18. accommodating the substrate inside a cylindrical heating element disposed in a processing chamber; a heating unit provided to surround the processing vessel to heat the cylindrical heating element; and controlling the heating section based on a temperature measured by a temperature measuring assembly disposed inside the heating element and extending in an axial direction of the heating element; A method for manufacturing a semiconductor device, wherein the controlling process uses a temperature measurement assembly having a gas supply pipe having a flow path inside through which gas flows, a temperature sensor arranged outside the gas supply pipe and having a measurement unit for measuring temperature, and a protective tube in which the gas supply pipe and the temperature sensor are arranged, and the gas sprayed into the protective tube from an injection port of the gas supply pipe arranged at a position higher than the temperature sensor descends in the gap between the outer wall of the temperature sensor and the inner wall of the protective tube.

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