JP2008258240A - Substrate processing equipment - Google Patents

Abstract

【Task】
Provided is a substrate processing apparatus capable of suppressing generation of impurities and generation of particles while preventing burning of a sealing member for sealing a processing tube.
[Solution]
A processing tube 32 made of transparent quartz having a flange portion protruding outward at the open end and partitioning the processing chamber 17 for processing the substrate 3, and a heating means 31 provided outside the processing chamber for heating the substrate. A gas supply means 35 for supplying a desired gas into the processing tube, a discharge means 34 for discharging the atmosphere in the processing tube, a member 33 that partitions the processing chamber together with the processing tube, and the processing chamber is airtight. And an O-ring interposed between the end surface of the flange portion and the end surface of the member, the flange portion includes a transparent quartz layer that forms the end surface of the flange portion, and the transparent A thickness obtained by excluding the thickness of the transparent quartz layer from the thickness of the flange portion adjacent to the entire surface of the quartz layer facing the O-ring contact surface and perpendicular to the facing surface. Formed with a thickness less than And an opaque quartz layer is provided.
[Selection] Figure 2

Description

  The present invention is a substrate processing apparatus for storing a substrate such as a silicon wafer in a processing chamber in a processing furnace, and performing processing such as thin film formation, impurity diffusion, annealing, and etching on the substrate surface, particularly the processing chamber is transparent. The present invention relates to a substrate processing apparatus defined by a quartz processing tube.

  As one process for manufacturing a semiconductor device, there is a substrate processing process in which a substrate processing apparatus performs processing such as generation of a thin film, diffusion of impurities, annealing, and etching on a substrate surface such as a silicon wafer or a glass substrate.

  In addition, as the substrate processing apparatus, there are a single-wafer type substrate processing apparatus that processes substrates one by one, a batch type substrate processing apparatus that processes a specified number of substrates at a time, and a vertical type as a batch type substrate processing apparatus. There are a vertical substrate processing apparatus having a mold furnace and a horizontal substrate processing apparatus having a horizontal furnace.

  For example, a vertical type substrate processing apparatus has a cylindrical processing tube defining a processing chamber and a heater provided surrounding the processing tube, and the substrate to be processed is processed in multiple stages by a substrate holder. The substrate and the processing chamber are heated by the heater while the processing chamber is hermetically sealed, and the substrate processing is performed by introducing a predetermined processing gas into the processing chamber.

  The processing tube has a flange at the open end, and is fixed to the support member and the strength member via the flange. As described above, since the processing chamber defined by the processing tube is required to be airtight, a sealing member such as an O-ring is provided on the joint surface of the flange, and the joint surface is hermetically sealed.

  A material such as an O-ring is generally an organic material such as a synthetic rubber and may be burned out at high temperatures. For this reason, countermeasures have been taken so that the O-ring does not burn out due to heat from the flange.

  FIG. 4 shows an example of a conventional measure, and shows a cross section of the open end portion of the processing tube.

  In FIG. 4, reference numeral 32 denotes a processing tube that defines the processing chamber 17, and the processing tube 32 includes a processing tube main body 72 and a flange portion 73 welded to the lower end of the processing tube main body 72. The processing tube main body 72 is made of transparent quartz and has a cylindrical shape with a closed upper end, and the flange portion 73 is made of opaque quartz. It has a donut disk-like flange 75 which is located at the lower end of the cylindrical portion 74 and is formed so as to be orthogonal to the axial center of the cylindrical portion 74. The opaque quartz contains a large amount of fine bubbles inside, and blocks heat radiation and has a large resistance to heat conduction.

  In the figure, reference numeral 76 denotes a manifold, which is made of metal such as stainless steel, has a cylindrical shape concentric with the processing tube 32, and is orthogonal to the axis of the processing tube 32 at the upper end. A support flange 77 is provided.

  The cross section of the supporting flange 77 has a step shape in which the outer peripheral edge is set back by a required step with respect to the inner peripheral edge, and the upper surface of the inner peripheral edge is a processing tube mounting surface on which the processing tube 32 is mounted. 78, the upper surface of the outer peripheral edge portion is a seal surface 79.

  In the state where an O-ring 81 is provided around the inner peripheral edge, a cushion 82 is provided outside the O-ring 81, and the processing tube 32 is mounted on the processing tube mounting surface 78, the flange 75. The O-ring 81 and the cushion 82 are interposed in a compressed state between the lower surface of the sealing member and the sealing surface 79.

  By fixing a fixing ring 83 having an inverted L-shaped cross section to the supporting flange 77 with a cushion 84 interposed therebetween, the flange 75 is held between the fixing ring 83 and the supporting flange 77, and The processing tube 32 is supported and fixed to the manifold 76. The boundary between the lower end of the processing tube 32 and the upper end of the manifold 76 is hermetically sealed by the O-ring 81.

  As described above, the processing tube main body 72 is heated by the heater, and the O-ring 81 is heated by heat conduction from the processing tube main body 72 and by heat radiation from the inside of the processing tube main body 72. . Since the flange portion 73 is made of opaque quartz and has a large thermal resistance, heat conduction from the processing tube main body 72 is suppressed, and since it is opaque, heat radiation from the inside of the processing tube main body 72 is achieved. Shut off. The O-ring 81 is prevented from being burned out by the heat blocking action of the flange portion 73.

  Etching is one of the substrate processes, or etching for cleaning the processing chamber 17. When etching is performed, bubbles contained in the flange portion 73 may be released, and the surface may be extremely roughened. On the roughened surface, the adhesion of the O-ring 81 is impaired, and the airtightness is lowered. Furthermore, the roughened surface becomes easy to take in impurities and becomes brittle. This causes generation of particles.

  In addition, there exist a thing shown by patent document 1 and patent document 2 as a well-known example which used the opaque quartz for the flange part of the processing tube, or a part of flange part. However, Patent Documents 1 and 2 have a structure in which an opaque quartz portion has a large exposed area in the processing chamber.

  With the ultra-high integration of semiconductor devices such as LSIs, defects and impurities at levels that have been ignored in the past have become a problem in the semiconductor manufacturing process. For this reason, there are an increasing number of customers who use high-purity quartz that eliminates impurity contamination by using quartz materials with low impurity concentration and low OH groups and reviewing the production process of quartz glass for impurity contamination from quartz parts. Yes.

  Opaque quartz has a higher impurity concentration such as Fe, Al, Na, Cu and the content of OH groups than high-purity quartz. In Patent Document 1 and Patent Document 2, the opaque portion exposed to the processing chamber There was a risk of contamination from impurities.

  Further, the transparent quartz and the opaque quartz have a problem that the strength of the transparent quartz is higher, and the strength of the flange portion is lowered when the opaque quartz is thickened or increased.

JP 2000-349028 A

Japanese Utility Model Publication No. 57-51639

  In view of such circumstances, the present invention provides a substrate processing apparatus capable of suppressing generation of impurities and generation of particles while preventing burning of a sealing member for sealing a processing tube.

  The present invention includes a processing tube made of transparent quartz having a flange portion protruding outward at an open end, and defining a processing chamber for processing a substrate, and a heating means provided outside the processing chamber for heating the substrate. Gas supply means for supplying a desired gas into the processing tube, discharge means for discharging the atmosphere in the processing tube, a member for partitioning the processing chamber together with the processing tube, and the processing chamber being airtightly partitioned. Therefore, an O-ring interposed between the end surface of the flange portion and the end surface of the member is provided. The flange portion includes a transparent quartz layer that forms the end surface of the flange portion, and the transparent quartz layer. The thickness of the flange portion adjacent to the entire surface facing the O-ring contact surface and perpendicular to the facing surface is less than the thickness excluding the thickness of the transparent quartz layer. An opaque quartz layer formed with a thickness and Relates to a substrate processing apparatus is provided, and the opaque quartz layer is 3 mm, in which according to the substrate processing apparatus is a transparent quartz layer or 2 mm.

  According to the present invention, a flange portion projecting outward is provided at an open end, and a processing tube made of transparent quartz that defines a processing chamber for processing a substrate, and provided outside the processing chamber for heating the substrate. A heating means, a gas supply means for supplying a desired gas into the processing tube, a discharge means for discharging the atmosphere in the processing tube, a member that partitions the processing chamber together with the processing tube, and the processing chamber is hermetically sealed In order to partition, an O-ring interposed between the end surface of the flange portion and the end surface of the member is provided. The flange portion includes a transparent quartz layer forming the end surface of the flange portion, and the transparent quartz From the thickness of the flange portion in the direction adjacent to the entire surface of the layer facing the O-ring contact surface and perpendicular to the facing surface, excluding the thickness of the transparent quartz layer Opaque stone formed with a thin thickness Therefore, the opaque quartz layer suppresses heat conduction and heat radiation to the seal member, prevents overheating burnout, and the seal member comes into contact with the transparent quartz layer, resulting in a rough surface. Since there is no airtightness, the opaque quartz layer comes into contact with the processing chamber only on the peripheral surface, and it is possible to suppress the generation of impurities and particles generated from the opaque quartz layer. Demonstrate.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  First, a substrate processing apparatus in which the present invention is implemented will be described with reference to FIG.

  In FIG. 1, reference numeral 1 denotes a substrate processing apparatus, 2 denotes a substrate storage container (cassette), and a substrate (wafer) 3 such as a silicon wafer processed by the substrate processing apparatus 1 has a required number, for example 25, in the cassette 2. It is carried in and out in a state where the sheets are stored.

  A front maintenance port 6 is opened as a maintenance opening in the lower part of the front wall 5 of the housing 4 of the substrate processing apparatus 1, and the front maintenance port 6 can be opened and closed by a front maintenance door (not shown). ing. A substrate storage container inlet / outlet 8 for loading / unloading the cassette 2 is opened above the front maintenance port 6. The substrate storage container inlet / outlet 8 is opened and closed by an inlet / outlet opening / closing mechanism (front shutter) (not shown). It is designed to be opened and closed.

  A substrate storage container transfer device (cassette transfer stage) 11 is provided inside the housing 4 and in contact with the substrate storage container inlet / outlet 8, and faces the cassette transfer stage 11 to store the required number of cassettes 2. A lower substrate storage container storage shelf (cassette shelf) 12 and an upper substrate storage container storage shelf (buffer cassette shelf) 13 are provided.

  A substrate storage container transfer device (cassette transfer device) 14 is provided between the cassette transfer stage 11 and the cassette shelf 12 and the buffer cassette shelf 13. The cassette carrying device 14 includes a traversing mechanism, an elevating mechanism, and a rotating mechanism. The cassette carrying device 14 cooperates with the traversing mechanism, the raising and lowering mechanism, and the rotating mechanism, so that the cassette transfer stage 11 and the cassette shelf 12, The cassette 2 can be transported in a required posture with the buffer cassette shelf 13.

  A load lock chamber 15, which is an airtight container, is provided in the rear and lower portions of the housing 4, and a processing furnace 16 is erected above the load lock chamber 15. The processing furnace 16 includes an airtight processing chamber 17. The processing chamber 17 is connected to the load lock chamber 15 in an airtight manner, and a furnace port portion at the lower end of the processing chamber 17 is airtightly connected by a furnace port gate valve 20. It can be closed.

  A substrate holder (boat) 18 can be accommodated in the load lock chamber 15. The boat 18 is made of a heat-resistant material such as quartz or silicon carbide, and can hold the wafers 3 in a multi-stage in a horizontal posture. It has become. In the lower part of the boat 18, a plurality of heat insulating plates (not shown) 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, The downward heat dissipation is suppressed.

  Further, a substrate holder lifting mechanism (boat elevator) 19 for supporting the boat 18 and loading / unloading the boat 18 to / from the processing chamber 17 is provided in the load lock chamber 15.

  The load lock chamber 15 is provided with a substrate transfer port 21 for transferring the wafer 3 to the boat 18. The substrate transfer port 21 is opened by a gate valve 25 and is airtightly closed. A gas supply system 22 that supplies an inert gas such as nitrogen gas is connected to the load lock chamber 15, and an exhaust device (not shown) that exhausts the inside of the load lock chamber 15 to make it negative pressure is connected. ing.

  A substrate transfer device (substrate transfer device) 23 is provided between the load lock chamber 15 and the cassette shelf 12, and the substrate transfer device 23 requires a substrate holding plate 24 for mounting and holding the wafer 3. It has a number (for example, 5), and also includes an elevating mechanism unit for elevating and lowering the substrate holding plate 24, a rotating mechanism unit for rotating, and an advancing / retreating mechanism unit for moving back and forth.

  The substrate transfer machine 23 is configured to move the substrate between the boat 18 in the lowered state and the cassette shelf 12 via the substrate transfer port 21 through the cooperation of the lifting mechanism unit, the rotation mechanism unit, and the advance / retreat mechanism unit. Transfer is to be performed.

  A clean unit 26 is provided at a required position inside the housing 4, for example, facing the buffer cassette shelf 13, and a clean atmosphere flow is formed inside the housing 4 by the clean unit 26.

  Hereinafter, the operation of the substrate processing apparatus 1 will be described.

  The substrate storage container inlet / outlet 8 is opened by a front shutter (not shown), and the cassette 2 is carried in from the substrate storage container inlet / outlet 8. The cassette 2 to be loaded is placed so that the wafer 3 is in a vertical posture and the entrance / exit of the wafer 3 faces upward.

  Next, the cassette transport device 14 transports the cassette shelf 12 or the buffer cassette shelf 13 to a designated shelf position. The cassettes 2 stored in the cassette shelves 12 and the buffer cassette shelves 13 are in a horizontal posture, and the entrance / exit is directed to the substrate transfer machine 23. Further, after being temporarily stored, the cassette carrying device 14 transfers the buffer cassette shelf 13 to the cassette shelf 12.

  The inside of the load lock chamber 15 is previously set to atmospheric pressure, and the boat 18 is lowered into the load lock chamber 15 by the boat elevator 19. The substrate transfer port 21 is opened by the gate valve 25, and the wafer 3 is transferred from the cassette 2 to the boat 18 by the substrate transfer machine 23.

  When a predetermined number of wafers 3 are loaded in the boat 18, the substrate transfer port 21 is closed by the gate valve 25, and the load lock chamber 15 is evacuated by an exhaust device. Depressurized. When the load lock chamber 15 is depressurized to the same pressure as that in the processing chamber 17, the furnace port portion of the processing chamber 17 is opened by the furnace port gate valve 20, and the boat elevator 19 The processing chamber 17 is charged.

  The wafer 3 is heated, the processing gas is introduced into the processing chamber 17, exhausted, and the like, and a predetermined processing is performed on the wafer 3.

  After the processing, the boat 18 is pulled out by the boat elevator 19, and the gate valve 25 is opened after the inside of the load lock chamber 15 is restored to atmospheric pressure. Thereafter, the wafer 3 and the cassette 2 are carried out of the casing 4 by the reverse procedure described above.

  With reference to FIG. 2, the processing furnace 16 and the boat elevator 19 will be described.

  As shown in FIG. 2, the processing furnace 16 has a heater 31 as a heating mechanism. The heater 31 has a cylindrical shape, is composed of a heater wire and a heat insulating member provided around the heater wire, and is vertically installed by being supported by a holding body (not shown).

  In the vicinity of the heater 31, a temperature sensor (not shown) is provided as a temperature detector for detecting the temperature in the processing chamber 17. A temperature control unit 45 is electrically connected to the heater 31 and the temperature sensor, and the inside of the processing chamber 17 is adjusted by adjusting the power supply to the heater 31 based on the temperature information detected by the temperature sensor. Control is performed at a desired timing so that the temperature has a desired temperature distribution.

  A processing tube 32 is disposed inside the heater 31 concentrically with the heater 31. The processing tube 32 is made of a heat resistant material such as quartz (SiO2) or silicon carbide (SiC), and is formed in a cylindrical shape with the upper end closed and the lower end opened. The processing tube 32 defines the processing chamber 17 and stores the boat 18, and the wafer 3 is stored in the processing chamber 17 while being held in the boat 18.

  Below the processing tube 32, a manifold 33 is disposed concentrically with the processing tube 32, and the processing tube 32 is erected on the manifold 33. The manifold 33 is made of, for example, stainless steel and has a cylindrical shape with an upper end and a lower end opened. An O-ring 81 (described later) is provided as a seal member between the manifold 33 and the processing tube 32. Since the manifold 33 is supported by a holding body, for example, the load lock chamber 15, the processing tube 32 is in a vertically installed state. A reaction vessel is formed by the processing tube 32 and the manifold 33.

  FIG. 3 is an enlarged view of a portion L in FIG. 2, and shows details of a joint portion between the lower end portion of the processing tube 32 and the upper end portion of the manifold 33. In FIG. 3, the same components as those shown in FIG. 4 are denoted by the same reference numerals.

  The processing tube 32 has a processing tube main body 72 made of transparent quartz, and a flange 75 made of transparent quartz is integrally formed with the processing tube main body 72 at the lower end portion of the processing tube main body 72 or by welding. It has become.

  The flange 75 has an annular shape, and the central space forms the opening of the processing tube 32. An opaque quartz layer 86 is formed on the opening side end surface (lower end surface in the drawing) of the flange 75, and a transparent quartz layer 85 is formed on the opening side end surface of the opaque quartz layer 86, and the opening side end surface of the transparent quartz layer 85 is formed. Is flattened and burned with a burner. Further, depending on the properties of the opening side end face, a polishing process is performed. Burner finish makes the surface smooth and transparent.

  The opaque quartz layer 86 may be formed by welding an opaque quartz donut disk or by welding. Similarly, the transparent quartz layer 85 may be formed by welding a doughnut-shaped disc made of transparent quartz or by overlaying by welding.

  The opaque quartz layer 86 may be thick enough to obtain a heat blocking effect, and the transparent quartz layer 85 may be thick enough to polish the opening end face. For example, the thickness of the flange 75 is 7 mm, the thickness of the opaque quartz layer 86 is smaller than the thickness of the flange 75, for example, about 3 mm so as not to lose opacity, and the thickness of the transparent quartz layer 85 is etched in the cleaning process. In consideration of receiving, etc., about 2 mm.

  Similar to the manifold 76 shown in FIG. 4, the manifold 33 has a substantially cylindrical shape, and has a supporting flange 77 joined to the flange 75 at the upper end.

  The cross section of the supporting flange 77 has a step shape in which the outer peripheral edge is set back by a required step with respect to the inner peripheral edge, and the upper surface of the inner peripheral edge is a processing tube mounting surface on which the processing tube 32 is mounted. 78, the upper surface of the outer peripheral edge portion is a seal surface 79.

  In the state where the O-ring 81 is provided around the inner peripheral edge and the processing tube 32 is mounted on the processing tube mounting surface 78, the O-ring 81 is pressed against the polishing surface of the transparent quartz layer 85. The

  The flange 75 is held between the support flange 77 and the cushion 82 and the cushion 84 by a fixed ring 83 having an inverted L-shaped cross section. The processing tube 32 is supported and fixed to the manifold 33, and the joint between the flange 75 and the supporting flange 77 is hermetically sealed by the O-ring 81.

  The opaque quartz layer 86, which is opaque quartz, suppresses heat conduction from the processing tube main body 72, blocks heat radiation from the inside of the processing tube main body 72, and prevents the O-ring 81 from being overheated and damaged. To prevent.

  The manifold 33 is provided with a gas exhaust pipe 34 and a gas supply pipe 35 penetrating therethrough. The gas supply pipe 35 is branched into three on the upstream side, and the first gas supply source 42 and the second gas supply source 43 are connected through valves 36, 37, 38 and MFCs 39, 40, 41 as gas flow rate control devices. , And the third gas supply source 44, respectively.

  A gas flow rate control unit 46 is electrically connected to the MFCs 39, 40, 41 and the valves 36, 37, 38, and the gas flow rate control unit 46 is configured so that the flow rate of the supplied gas becomes a desired flow rate. It is configured to control at a desired timing.

  A vacuum exhaust device 48 such as a vacuum pump is connected to the downstream side of the gas exhaust pipe 34 via a pressure sensor (not shown) as a pressure detector and an APC valve 47 as a pressure regulator. The vacuum exhaust device 48 is preferably a tertiary vacuum pump having a high exhaust capability, such as a molecular turbo pump + mechanical booth and pump + dry pump.

  A pressure control unit 49 is electrically connected to the pressure sensor and the APC valve 47, and the pressure control unit 49 adjusts the opening degree of the APC valve 47 based on the pressure detected by the pressure sensor. Thus, the pressure is controlled at a desired timing so that the pressure in the processing chamber 17 becomes a desired pressure.

  In the configuration of the processing furnace 16, the first processing gas is supplied from the first gas supply source 42, and its flow rate is adjusted by the MFC 39, and then the gas supply pipe is connected via the valve 36. 35 is introduced into the processing chamber 17. The second processing gas is supplied from the second gas supply source 43, the flow rate of which is adjusted by the MFC 40, and then introduced into the processing chamber 17 through the valve 37 through the gas supply pipe 35. . The third processing gas is supplied from the third gas supply source 44, the flow rate of which is adjusted by the MFC 41, and then introduced into the processing chamber 17 from the gas supply pipe 35 through the valve 38. . Further, the gas in the processing chamber 17 is exhausted from the processing chamber 17 by the vacuum exhaust device 48 connected to the gas exhaust pipe 34.

  The boat elevator 19 will be described.

  The drive mechanism 51 of the boat elevator 19 is provided on the side wall of the load lock chamber 15.

  The drive mechanism 51 includes a guide shaft 52 and a ball screw 53 which are erected in parallel. The ball screw 53 is rotatably supported and is rotated by an elevating motor 54. A lifting platform 55 is slidably fitted to the guide shaft 52 and is screwed to the ball screw 53, and a hollow lifting shaft 56 is suspended from the lifting platform 55 in parallel with the guide shaft 52. .

  The elevating shaft 56 passes through the ceiling surface of the load lock chamber 15 and extends to the inside, and a hollow drive unit storage case 57 is airtightly provided at the lower end. A bellows 58 is provided so as to cover the lifting shaft 56 in a non-contact manner. The upper end of the bellows 58 is fixed to the lower surface of the lifting platform 55 and the lower end of the bellows 58 is fixed to the upper surface of the load lock chamber 15 in an airtight manner. The elevating shaft 56 and the loose portion of the elevating shaft 56 are hermetically sealed.

  A furnace port 59 is provided concentrically with the manifold 33 at the ceiling of the load lock chamber 15, and the furnace port 59 can be hermetically closed by a seal cap 61. The seal cap 61 is made of, for example, a metal such as stainless steel, is formed in a disk shape, and is airtightly fixed to the upper surface of the drive unit storage case 57.

  The drive unit storage case 57 has an airtight structure, and the inside is isolated from the atmosphere in the load lock chamber 15. A boat rotation mechanism 62 is provided inside the drive unit storage case 57, and the rotation shaft of the boat rotation mechanism 62 extends upward through the top plate of the drive unit storage case 57 and the seal cap 61. The boat mounting table 63 is fixed to the upper end, and the boat 18 is mounted on the boat mounting table 63.

  The seal cap 61 and the boat rotating mechanism 62 are cooled by water-cooled cooling mechanisms 64 and 65, respectively, and a cooling water pipe 66 to the cooling mechanisms 64 and 65 passes through the elevating shaft 56 to provide an external cooling water source. (Not shown). The boat rotating mechanism 62 is supplied with power through a power supply cable 67 wired through the elevating shaft 56.

  A drive control unit 68 is electrically connected to the boat rotation mechanism 62 and the lift motor 54, and is configured to control at a desired timing so as to perform a desired operation.

  The temperature control unit 45, the gas flow rate control unit 46, the pressure control unit 49, and the drive control unit 68 also constitute an operation unit and an input / output unit, and a main control unit 69 that controls the entire substrate processing apparatus 1. Is electrically connected.

  Next, a method for forming a film on a substrate such as the wafer 3 as one step of the semiconductor device manufacturing process using the processing furnace 16 will be described. In the following description, the operation of each unit constituting the substrate processing apparatus 1 is controlled by the main control unit 69.

  When a predetermined number of wafers 3 are loaded into the boat 18, the ball screw 53 is rotated by driving the lifting motor 54, and the driving unit storage case 57 is lifted via the lifting platform 55 and the lifting shaft 56. Then, the boat 18 is charged into the processing chamber 17. In this state, the seal cap 61 hermetically closes the furnace port 59 via an O-ring.

  The processing chamber 17 is evacuated by the evacuation device 48 so that a desired pressure (degree of vacuum) is obtained. At this time, the pressure in the processing chamber 17 is measured by a pressure sensor, and the APC valve 47 is feedback-controlled based on the measured pressure. Further, the processing chamber 17 is heated by the heater 31 so as to have a desired temperature and a desired temperature distribution, and the heating state is feedback-controlled by the temperature control unit 45 based on temperature information detected by a temperature sensor. Subsequently, the boat 3 is rotated by rotating the boat 18 by the boat rotating mechanism 62.

  Respective processing gases are supplied from the first gas supply source 42, the second gas supply source 43, and the third gas supply source 44. After the openings of the MFCs 39, 40, and 41 are adjusted so as to obtain a desired flow rate, the valves 36, 37, and 38 are opened, and the respective processing gases flow through the gas supply pipe 35 to perform the processing. It is introduced into the processing chamber 17 from the upper part of the chamber 17. The introduced gas passes through the inside of the processing chamber 17 and is exhausted from the gas exhaust pipe 34. The processing gas contacts the wafer 3 when passing through the processing chamber 17, and an EPI film grows on the surface of the wafer 3 and is deposited (deposited).

  When a preset time elapses, an inert gas is supplied from an inert gas supply source (not shown), the inside of the processing chamber 17 is replaced with the inert gas, and the pressure in the processing chamber 17 is returned to normal pressure. Will be restored.

  Thereafter, the seal cap 61 is lowered by the boat elevator 19 to open the furnace port 59 and the boat 18 is carried out from the furnace port 59 into the load lock chamber 15. After cooling to the required temperature in the load lock chamber 15, the substrate transfer port 21 is opened, and the processed wafer 3 is taken out from the boat 18 by the substrate transfer device 23 (see FIG. 1).

  In the substrate processing process, the processing tube 32 and the wafer 3 are heated by a heater, and the O-ring 81 is heated by heat conduction from the processing tube main body 72 and by heat radiation from the inside of the processing tube main body 72. The The opaque quartz layer 86 is made of opaque quartz and has a large thermal resistance. Therefore, the opaque quartz layer 86 suppresses heat conduction from the processing tube main body 72 and is opaque, so that heat radiation from the inside of the processing tube main body 72 is prevented. Cut off. The heat blocking action of the opaque quartz layer 86 prevents the O-ring 81 from being burned out.

  Further, when the substrate processing is etching, or when the processing tube 32 is cleaned by etching, the opaque quartz layer 86 is exposed to the processing chamber 17 only on the inner peripheral surface with a small thickness. Therefore, the generation of impurities is suppressed, and the generation of particles can be greatly reduced.

  Further, the opening-side end surface of the flange 75 in contact with the O-ring 81 is transparent quartz and does not become a rough surface due to the influence of etching, so that airtightness is not impaired.

  As an example, the processing conditions for processing a wafer in the processing furnace of the present embodiment include, for example, a processing temperature of 750 to 850 ° C., a processing pressure of 1000 Pa, a gas type and a gas in the H 2 annealing process. The supply flow rate H 2, 20 l is exemplified, and the wafer is processed by maintaining each processing condition constant at a certain value within each range.

  Further, the processing furnace 16 of the substrate processing apparatus may be a horizontal processing furnace, and the processing tube is open at both ends, provided with flange portions that form openings at both ends, and at least one flange portion is provided with an opaque quartz. A transparent quartz layer may be formed with the layer interposed.

It is a perspective view which shows an example of the substrate processing apparatus which concerns on embodiment of this invention. It is a schematic sectional drawing of the processing furnace used for this substrate processing apparatus. It is the L section enlarged view of FIG. It is sectional drawing of the process tube opening end part used for the conventional substrate processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 3 Wafer 15 Load lock chamber 16 Processing furnace 17 Processing chamber 18 Boat 31 Heater 34 Gas exhaust pipe 35 Gas supply pipe 42 1st gas supply source 43 2nd gas supply source 44 3rd gas supply source 45 Temperature control part 46 Gas flow control unit 49 Pressure control unit 68 Drive control unit 69 Main control unit 72 Processing tube body 75 Flange 77 Supporting flange 78 Processing tube mounting surface 81 O-ring 85 Transparent quartz layer 86 Opaque quartz layer

Claims (1)

  A processing tube made of transparent quartz having a flange portion protruding outward at an open end and defining a processing chamber for processing a substrate, heating means provided outside the processing chamber for heating the substrate, and the processing A gas supply means for supplying a desired gas into the pipe; a discharge means for discharging the atmosphere in the processing pipe; a member for partitioning the processing chamber together with the processing pipe; and the flange for airtightly partitioning the processing chamber. And an O-ring interposed between the end face of the member and the end face of the member, the flange portion having a transparent quartz layer forming the end face of the flange portion, and the O-ring contact of the transparent quartz layer Formed with a thickness smaller than the thickness of the flange portion excluding the thickness of the transparent quartz layer from the thickness of the flange portion adjacent to the entire surface facing the surface and perpendicular to the facing surface. And an opaque quartz layer to be provided A substrate processing apparatus, characterized in that.

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