JP2013191695A - Substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate processing apparatus which easily secures the position reproducibility of a temperature sensor and improves the temperature detection accuracy.SOLUTION: A substrate processing apparatus includes: a heater 19; a reaction tube 24 defining a processing chamber 13 where a substrate 16 held by a substrate holder 15 is processed; a temperature sensor 45 having a protection tube 49 which extends upward along an inner surface of the reaction tube and into which a thermo-couple is inserted, the protection tube 49 provided with a first positioning member 54 provided in at least one position so as to protrude toward an inner wall of the reaction tube; and a second positioning member 55 having a fitting groove 56 into which the first positioning member fits. The second positioning member is disposed between the protection tube and the reaction tube with the first positioning member fitting into the fitting groove.

Description

  The present invention relates to a substrate processing apparatus that performs processing such as thin film generation, oxidation processing, impurity diffusion, annealing processing, etching, and the like on a substrate such as a silicon wafer or a glass substrate.

  As the substrate processing apparatus, there are a single-wafer type substrate processing apparatus that processes substrates one by one and a batch type substrate processing apparatus that processes a required number of substrates at a time. A batch type substrate processing apparatus has a vertical furnace, and a required number of substrates are stored in a processing chamber of the vertical furnace and processed.

  The reaction tube (process tube) that defines the processing chamber of the vertical furnace has a cylindrical shape, and surrounds the process tube with a temperature sensor such as a thermocouple installed in the process tube. A heating device is provided. In the processing chamber, substrates (wafers) are supported in multiple stages in a horizontal posture by a substrate holder (boat), the processing chamber is depressurized to a predetermined processing pressure, heated to a predetermined temperature, and a processing gas is being introduced. By evacuating, the substrate surface is processed as required.

  A conventional temperature sensor 1 will be described with reference to FIG. The temperature sensor 1 is composed of a plurality of thermocouples (not shown) inserted into a protective tube 2 such as quartz. The protective tube 2 penetrates the manifold 4 disposed below the process tube 3 from the peripheral surface, is bent vertically, and extends upward along the inner wall of the process tube 3.

  When the temperature sensor 1 is removed for maintenance or the like and is attached again, an accurate temperature distribution cannot be obtained if the attachment position of the temperature sensor 1 is different from the position before removal. There is a need for a means for achieving reproducibility.

  In the conventional temperature sensor 1, a weight support member 6 that contacts the bent portion of the protective tube 2 and supports the weight of the protective tube 2, and a displacement prevention member 7 that performs horizontal positioning and restrains horizontal movement. And a protrusion 5 provided to ensure parallelism with the inner wall of the process tube 3. The protrusion 5 protrudes toward the inner wall of the process tube 3, and the protrusion 5 is brought into contact with the inner wall of the process tube 3, thereby achieving position reproducibility of the protective tube 2.

  However, the conventional protective tube 2 has a structure in which the protrusion 5 is always in contact with the inner wall of the process tube 3, so that the protrusion 5 is damaged due to thermal deformation when the processing chamber is decompressed and heated. However, the protection tube 2 itself may be damaged along with the breakage of the protrusion 5, and the protection tube 2 is damaged, causing a problem of wafer lotout.

  Further, since the conventional protective tube 2 does not have a configuration for preventing tilting to the boat, when the protective tube 2 is installed inclined to the boat side, the protective tube 2 and the boat Contact with each other, which is a factor in generating particles.

  In Patent Document 1, a thermocouple holder, in which a thermocouple is inserted into a protective tube from the lower end, both end portions are thick cylindrical portions, and a flange portion is formed in the middle, is provided at a required position of the thermocouple fixing bracket. After positioning, the cylindrical part is fitted to the base part of the clamp fitting, and the flange part is abutted and fixed to the clamp fitting from below, so that the reproducibility in the height direction when reassembling the temperature detector is achieved. An improved semiconductor manufacturing apparatus is disclosed.

  In Patent Document 2, the inside of the protective tube is divided into four spaces by a partition plate, and one thermocouple is accommodated in each space. The storage space for each thermocouple is narrowed, and each thermoelectric There has been disclosed a substrate processing apparatus and a substrate processing method for ensuring the reproducibility of the position of the thermocouple in the protective tube when the internal thermocouple is remounted by restricting the horizontal displacement of the pair.

Japanese Patent Laid-Open No. 2004-22943 JP 2007-266439 A

  In view of such circumstances, the present invention provides a substrate processing apparatus that easily secures position reproducibility of a temperature sensor and improves temperature detection accuracy.

  The present invention includes a heater, a reaction tube that defines a processing chamber for processing a substrate held by a substrate holder, and extends upward along the inner surface of the reaction tube, and a thermocouple is inserted therein. A temperature sensor having a protective tube provided with a first positioning member protruding toward the inner wall of the reaction tube in at least one place, and a second positioning member having a fitting groove into which the first positioning member is fitted. And a substrate processing apparatus in which the second positioning member is interposed between the protective tube and the reaction tube in a state where the first positioning member is fitted in the fitting groove.

  The present invention further relates to a substrate processing apparatus further comprising an inclination limiting member having a concave portion surrounding the protective tube, wherein the concave portion limits the inclination of the protective tube.

  According to the present invention, a heater, a reaction tube that defines a processing chamber for processing a substrate held by a substrate holder, and an upward extending along the inner surface of the reaction tube, a thermocouple is inserted therein. And a temperature sensor having a protective tube provided with a first positioning member protruding toward the inner wall of the reaction tube at at least one location, and a second positioning having a fitting groove into which the first positioning member is fitted. And the second positioning member is interposed between the protective tube and the reaction tube in a state in which the first positioning member is fitted in the fitting groove. The position reproducibility of the temperature sensor in the surface of the processing chamber can be easily ensured by the thickness of the processing chamber, and the position reproducibility of the second positioning member in the height direction relative to the first positioning member can be ensured. .

  According to the present invention, there is further provided an inclination limiting member having a recess surrounding the protection tube, and the recess limits the inclination of the protection tube, so that the temperature sensor is inclined to incline the protection tube and the substrate. An excellent effect of preventing the generation of particles due to contact with the holder is exhibited.

It is sectional drawing which shows an example of the processing furnace used for the substrate processing apparatus which concerns on the Example of this invention. It is a principal part enlarged view which shows the protective tube in the lower part of the said processing furnace, and its periphery structure. It is a principal part enlarged view which shows the protective tube in the upper part of the said processing furnace, and its periphery structure. It is a principal part enlarged view which shows the protection tube in the lower part of the conventional process furnace, and its periphery structure.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, referring to FIG. 1, an example of a processing furnace provided in a substrate processing apparatus according to an embodiment of the present invention will be described.

  The processing furnace 11 is erected above the preliminary chamber 12, the interior of the preliminary chamber 12 and the interior of the processing furnace 11 (processing chamber 13) are communicated, and the processing furnace 11 is a furnace port formed at the lower end. Is hermetically closed by a furnace port shutter (not shown) or a sealing lid 14.

  A boat 15 as a substrate holder is accommodated in the processing chamber 13, and wafers 16 as substrates to be processed are held in multiple stages in the horizontal position in the boat 15. Inside the preliminary chamber 12, a boat elevator 17 that is a substrate holder transfer device between the preliminary chamber 12 and the processing chamber 13 is provided, and from the boat elevator 17, an elevator that is a support body of the substrate holder is provided. The arm 18 extends in the horizontal direction. The boat 15 is supported by the lift arm 18 via the seal lid 14, and the boat 15 is lifted and lowered by the boat elevator 17 so that the boat 15 is loaded into and removed from the processing furnace 11. It has become.

  The processing furnace 11 has a heater 19 as a heating mechanism. The heater 19 has a cylindrical shape and is vertically installed by being supported by a heater base 21 as a holding plate.

  Inside the heater 19, a process tube 22 is disposed as a reaction tube concentrically with the heater 19. The process tube 22 includes an inner tube 23 as an internal reaction tube and an outer tube 24 as an external reaction tube provided on the outside thereof. The inner tube 23 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC), and has a cylindrical shape with upper and lower ends opened. The processing chamber 13 is defined inside the inner tube 23, and the boat 15 is loaded into the processing chamber 13.

  The outer tube 24 is made of, for example, a heat-resistant material such as quartz or silicon carbide, and has an inner diameter larger than the outer diameter of the inner tube 23 and has a cylindrical shape with an upper end closed and a lower end opened. It is provided concentrically with the tube 23. A cylindrical space 25 is formed between the inner tube 23 and the outer tube 24.

  A manifold 26 is disposed below the outer tube 24 so as to be concentric with the outer tube 24. The manifold 26 is made of, for example, stainless steel, and the outer tube 24 is erected at the upper end, and the inner tube 23 is erected on an inner flange 26 a that is formed on the inner side of the middle part of the manifold 26.

  An O-ring 27 as a seal member is provided between the manifold 26 and the outer tube 24. Since the manifold 26 is supported by the heater base 21, the process tube 22 is vertically installed. A reaction vessel is formed by the process tube 22 and the manifold 26, the lower end opening of the manifold 26 forms a furnace port, and the furnace port is hermetically closed by the seal lid 14. .

  A nozzle 28 as a gas introduction part is connected to the seal lid 14 so as to communicate with the inside of the processing chamber 13, and a gas supply pipe 29 is connected to the nozzle 28. A processing gas supply source and an inert gas supply source (not shown) are connected to the upstream side of the gas supply pipe 29 via a gas flow rate regulator (mass flow controller) 31. A gas flow rate control unit 32 is electrically connected to the gas flow rate adjuster 31, and is configured to control at a desired timing so that the flow rate of the supplied gas becomes a desired amount.

  An exhaust pipe 33 that exhausts the atmosphere in the processing chamber 13 communicates with the manifold 26. The exhaust pipe 33 communicates with the lower end portion of the cylindrical space 25.

  The exhaust pipe 33 is provided with a pressure sensor 34 and a valve device 35 as pressure detectors on the downstream side, and the exhaust pipe 33 is connected to a vacuum exhaust device 36 such as a vacuum pump.

  A pressure control unit 37 is electrically connected to the pressure sensor 34 and the valve device 35, and the pressure control unit 37 performs the processing by the valve device 35 based on the pressure detected by the pressure sensor 34. Control is performed at a desired timing so that the pressure in the chamber 13 becomes a desired pressure (degree of vacuum).

  The seal lid 14 that opens and closes the furnace port portion is made of a metal such as stainless steel and is formed in a disk shape. An O-ring 38 as a seal member that contacts the lower end of the manifold 26 is provided on the upper surface of the seal lid 14.

  A rotation mechanism 39 that rotates the boat 15 is installed below the seal lid 14. A rotation shaft 41 of the rotation mechanism 39 passes through the seal lid 14 and is connected to the boat 15 so that the boat 15 can rotate.

  The seal lid 14 is supported by the elevating arm 18, and the elevating arm 18 is supported by the boat elevator 17 so that the elevating arm 18 is raised and lowered by the boat elevator 17. The processing chamber 13 can be loaded and unloaded. A drive control unit 42 is electrically connected to the rotation mechanism 39 and the boat elevator 17, and is configured to control at a desired timing so as to perform a desired operation. Here, the rotating shaft 41, the seal lid 14, the lifting arm 18 and the like constitute a boat support portion.

  The boat 15 is made of, for example, a heat resistant material such as quartz or silicon carbide, and is configured to hold a plurality of wafers 16 in a horizontal posture and aligned in a state where the centers are aligned with each other in multiple stages. In the lower part of the boat 15, a heat insulating portion 44 in which a plurality of heat insulating plates 43 as a disk-shaped heat insulating member made of a heat resistant material such as quartz or silicon carbide are arranged in a multi-stage in a horizontal posture is configured. The heat from the heater 19 is not easily transmitted to the manifold 26 side.

  A temperature sensor 45 is installed in the process tube 22, and a temperature control unit 46 is electrically connected to the temperature sensor 45 and the heater 19, and the temperature information detected by the temperature sensor 45 is displayed. On the basis of this, by adjusting the degree of energization to the heater 19, the temperature of the processing chamber 13 is controlled at a desired timing so as to have a desired temperature distribution.

  The gas flow rate control unit 32, the pressure control unit 37, the drive control unit 42, and the temperature control unit 46 also constitute an operation unit and an input / output unit, and are electrically connected to a main control unit 47 that controls the entire substrate processing apparatus. Connected. The gas flow rate control unit 32, the pressure control unit 37, the drive control unit 42, the temperature control unit 46, and the main control unit 47 are configured as a controller 48.

  2 and 3, the temperature sensor 45 and its peripheral configuration will be described.

  FIG. 2 shows the temperature sensor 45 and its peripheral configuration in the lower part of the processing chamber 13. The temperature sensor 45 includes a protective tube 49 made of quartz or the like and a plurality of thermocouples (not shown) inserted into the protective tube 49.

  The protective tube 49 is inserted into the processing chamber 13 through a temperature sensor insertion hole 51 formed in the peripheral surface of the manifold 26, and then bent in the vertical direction in the processing chamber 13. Is extended upward between the outer tube 24 and the inner tube 23 (see FIG. 1).

  A weight support member 52 protruding from the manifold 26 is disposed below the bent portion 49 a of the protection tube 49, and the weight of the protection tube 49 is supported by the weight support member 52. Displacement preventing members 53 and 53 projecting from the manifold 26 are disposed on the side of the bent portion 49a, and the displacement preventing members 53 and 53 cause the protection tube 49 to move in the horizontal direction. Is restrained.

  A first positioning member 54 made of quartz protruding toward the wall surface of the outer tube 24 is welded to the vertical portion 49b of the protective tube 49, and the first positioning member 54 has a curved surface at least at the upper end. Have.

  The portion where the first positioning member 54 is formed between the vertical portion 49b and the outer tube 24 has a predetermined thickness, and the second positioning has four corners chamfered over the entire length in the vertical direction. A member 55 is interposed. The second positioning member 55 is formed with a fitting groove 56 having a predetermined depth from the middle part to the lower end and opened at the lower end. The first positioning member 54 is formed in the fitting groove 56 from below. It is supposed to be inserted. As the material of the second positioning member 55, a resin material such as PTFE (Polytetrafluoroethylene), PEEK (Polyetheretherone: registered trademark), PVC (Polyvinyl chloride), MC nylon (registered trademark) or the like is used.

  When the second positioning member 55 is interposed between the vertical portion 49b and the outer tube 24, the upper end of the first positioning member 54 inserted into the fitting groove 56 is the fitting groove. The second positioning member 55 is supported by being abutted against the upper end of 56, and the second positioning member 55 is positioned, and the second positioning member 55 is positioned with respect to the vertical portion 49b. The position 55 is always constant. Further, the second positioning member 55 is chamfered, so that when the second positioning member 55 is interposed, only the corners come into contact with the inner wall of the outer tube 24 so that the load is not concentrated. Yes.

  Further, the second positioning member 55 is interposed between the vertical portion 49b and the outer tube 24, and the outer tube 24 and the vertical portion 49b are in contact with the second positioning member 55. Thus, the distance between the outer tube 24 and the vertical portion 49b is always constant.

  The depth of the fitting groove 56 is deeper than the thickness of the first positioning member 54. That is, the thickness of the second positioning member 55 is thicker than the thickness of the first positioning member 54, so that the first positioning member 54 does not contact the outer tube 24.

  FIG. 3 shows the temperature sensor 45 and its peripheral configuration in the upper part of the processing chamber 13.

  A support column 57 is erected on the inner flange 26a. An inclination limiting member 58 supported by the support column 57 is provided at the upper portion of the processing chamber 13. The tilt limiting member 58 is a member having a combination of two rectangular parallelepipeds extending toward the outer tube 24. Two corners of the rear end are chamfered, and the rectangular parallelepiped on the front end side is a U-shaped recess. It is the surrounding part 61 in which 59 is formed.

  The concave portion 59 has a larger diameter than the vertical portion 49 b of the protective tube 49, and the vertical portion 49 b is accommodated in the concave portion 59, and the vertical portion 49 b is parallel to the boat 15. In the upright state, the vertical portion 49b is set to be positioned at the center of the concave portion 59.

  The vertical portion 49b can be tilted by a margin of the vertical portion 49b and the concave portion 59, and a state in which the vertical portion 49b is in contact with the inner surface of the concave portion 59 is the maximum inclination that the vertical portion 49b allows. It is. Further, the operator can use the concave portion 59 as a reference for the inclination of the vertical portion 49b. When the vertical portion 49b is in contact with the concave portion 59, the operator can confirm that the vertical portion 49b is inclined. As shown, the operator can visually determine whether the vertical portion 49b is inclined with respect to the boat 15.

  Next, a method of forming a thin film on the wafer 16 by the CVD method as one step of the semiconductor device manufacturing process using the processing furnace 11 according to the configuration shown in FIG. 1 will be described. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 48.

  When a predetermined number of wafers 16 are loaded into the boat 15, the boat 15 is loaded into the processing chamber 13 (boat loading) by the boat elevator 17. In this state, the seal lid 14 hermetically closes the furnace port portion via the O-ring 38.

  The processing chamber 13 is evacuated by the evacuation device 36 so as to have a desired pressure (degree of vacuum). At this time, the pressure in the processing chamber 13 is measured by the pressure sensor 34, and the pressure control unit 37 feedback-controls the valve device 35 based on the measured pressure.

  The processing chamber 13 is heated by the heater 19 so as to reach a desired temperature. At this time, the power supply to the heater 19 is feedback controlled based on the temperature information detected by the temperature sensor 45 so that the processing chamber 13 has a desired temperature distribution. Subsequently, the boat 15 is rotated by the rotating mechanism 39 and the wafer 16 is simultaneously rotated.

  Subsequently, a processing gas is supplied from a processing gas supply source (not shown), and the gas controlled to have a desired flow rate by the gas flow rate regulator 31 flows through the gas supply pipe 29 from the nozzle 28. It is introduced into the processing chamber 13. The introduced gas rises in the processing chamber 13, turns over the upper end opening of the inner tube 23, flows down the cylindrical space 25, and is exhausted from the exhaust pipe 33. The gas comes into contact with the surface of the wafer 16 as it passes through the processing chamber 13, and a thin film is deposited on the surface of the wafer 16 by a thermal CVD reaction.

  When a processing time set in advance elapses, an inert gas is supplied from an inert gas supply source (not shown). When the processing chamber 13 is replaced with an inert gas, the valve device 35 is closed, and the processing chamber is closed. The pressure of 13 is returned to normal pressure.

  Thereafter, the seal lid 14 is lowered by the boat elevator 17 to open the furnace opening, and the processed wafer 16 is pulled out from the processing chamber 13 while being held by the boat 15. Thereafter, the processed wafer 16 is discharged from the boat 15 by a substrate transfer device (not shown).

  After repeatedly performing the substrate processing, the temperature sensor 45 and the like were removed from the processing chamber 13 to remove deposits, and then adhered to the outer tube 24, the inner tube 23, the boat 15 and the like. The deposit is cleaned.

  When the removed temperature sensor 45 is attached again, the second positioning member 55 is interposed between the outer tube 24 and the vertical portion 49b of the protective tube 49, and the fitting groove 56 The second positioning member 55 is dropped so that the first positioning member 54 is inserted, and the upper end of the first positioning member 54 is brought into contact with the upper end of the fitting groove 56.

  Further, the second positioning member 55 interposed between the outer tube 24 and the protective tube 49 is in contact with the outer tube 24 and the protective tube 49, so that The height position of the second positioning member 55 and the distance between the outer tube 24 and the vertical portion 49b are reproduced.

  After the temperature sensor 45 and the like are attached again, the substrate processing is performed again.

  As described above, in this embodiment, the second positioning member 55 is interposed between the vertical portion 49 b of the protective tube 49 and the outer tube 24, and the outer tube is determined by the thickness of the second positioning member 55. 24, the distance between the vertical portion 49b, that is, the position of the vertical portion 49b in the processing chamber 13 can be kept constant, so that the temperature sensor 45 can be removed and reattached. Even if it exists, the reproducibility of the position can be secured easily.

  Further, since the thickness of the first positioning member 54 is thinner than the thickness of the second positioning member 55, the first positioning member 54 is brought into direct contact with the wall surface of the outer tube 24. The breakage of the first positioning member 54 and the breakage of the protective tube 49 due to the breakage of the first positioning member 54 can be prevented, the lot-out can be prevented, and the yield of the wafer 16 can be increased.

  Further, in this embodiment, since the inclination limiting member 58 that can confirm the inclination of the protective tube 49 is provided, the inclined protective tube 49 comes into contact with the boat 15 and particles are generated. Can be prevented.

  In the present embodiment, a second positioning member 55 is interposed between the outer tube 24 and the vertical portion 49b, and the outer tube 24 and the vertical portion 49b are brought into contact with the second positioning member 55, respectively. By doing so, the position reproducibility of the protective tube 49 has been achieved, but by making the depth of the fitting groove 56 shallower than the thickness of the first positioning member 54, the second positioning member 55 can be By interposing between the outer tube 24 and the first positioning member 54 and bringing the outer tube 24 and the first positioning member 54 into contact with the second positioning member, position reproducibility of the protective tube 49 is improved. You may plan.

  Further, in this embodiment, the four corners of the second positioning member 55 are chamfered to increase the contact area with the outer tube 24 and prevent the load from being concentrated. The contact surface with the outer tube 24 may be a curved surface having the same curvature as the inner wall of the outer tube 24.

  In this embodiment, the depth of the fitting groove 56 is made deeper than the thickness of the first positioning member 54, but the fitting groove 56 penetrates the second positioning member 55 in the thickness direction. You may form like.

  Further, in this embodiment, the first positioning member 54 and the second positioning member 55 are provided in one place, but the first positioning member 54 and the second positioning member 55 are provided in two or more places. Also good.

  Furthermore, in this embodiment, the tilt limiting member 58 that limits the tilt of the vertical portion 49b of the protective tube 49 is provided in only one place, but the tilt limiting member 58 may be provided in two or more places. Needless to say.

(Appendix)
The present invention includes the following embodiments.

  (Supplementary note 1) A heater, a reaction tube that defines a processing chamber for processing a substrate held by a substrate holder, and extends upward along the inner surface of the reaction tube. A thermocouple is inserted therein. A temperature sensor having a protective tube provided with a first positioning member protruding toward the inner wall of the reaction tube in at least one place, and a second positioning member having a fitting groove into which the first positioning member is fitted. The substrate processing apparatus, wherein the second positioning member is interposed between the protective tube and the reaction tube in a state where the first positioning member is fitted in the fitting groove.

  (Supplementary note 2) The substrate processing apparatus according to supplementary note 1, wherein a thickness of the second positioning member is larger than a thickness of the first positioning member.

  (Supplementary Note 3) The substrate processing apparatus according to Supplementary Note 1 or 2, wherein the depth of the fitting groove is deeper than the thickness of the first positioning member.

  (Supplementary Note 4) The substrate processing apparatus according to any one of Supplementary Notes 1 to 3, wherein the fitting groove penetrates the second positioning member in the thickness direction.

  (Supplementary Note 5) The substrate processing apparatus according to Supplementary Note 1 or 2, wherein the depth of the fitting groove is shallower than the thickness of the first positioning member.

DESCRIPTION OF SYMBOLS 11 Processing furnace 13 Processing chamber 15 Boat 16 Wafer 19 Heater 22 Process tube 23 Inner tube 24 Outer tube 45 Temperature sensor 49 Protection tube 54 1st positioning member 55 2nd positioning member 56 Fitting groove 58 Inclination limiting member

Claims (2)

  A heater, a reaction tube defining a processing chamber for processing the substrate held by the substrate holder, and extending upward along the inner surface of the reaction tube; a thermocouple is inserted therein; and at least one place A temperature sensor having a protective tube provided with a first positioning member projecting toward the inner wall of the reaction tube, and a second positioning member having a fitting groove into which the first positioning member is fitted, The substrate processing apparatus, wherein the second positioning member is interposed between the protective tube and the reaction tube in a state where the first positioning member is fitted in the fitting groove.   The substrate processing apparatus according to claim 1, further comprising an inclination limiting member having a concave portion surrounding the protective tube, wherein the concave portion limits an inclination of the protective tube.

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