Heat treatment system and state monitoring method

Abstract

To provide a technique capable of stably transporting a substrate by monitoring a state of a transport device of a heat treatment system.SOLUTION: A heat treatment system performs heat treatment on a plurality of substrates. The heat treatment system comprises a substrate holding tool for holding the plurality of substrates, a transport device that is provided in a loading region in which the substrate holding tool stands by and transports a substrate to the substrate holding tool, a controlling unit for controlling operation of the transport device, and a reference member installed in a moving range of the transport device in the loading region. The transport device includes a guide body for moving in parallel with respect to a longer direction of the substrate holding tool and a detection sensor for detection the reference member. The controlling unit makes the transport device move mutually with respect to the reference member to recognize a state of the guide body on the basis of detection of the reference member by the detection sensor.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a heat treatment system and a condition monitoring method. [Background technology]

[0002] Patent Document 1 discloses a heat treatment system (heat treatment apparatus) that carries a wafer boat (holding tool) holding a plurality of substrates (wafers) into a treatment vessel and performs heat treatment on each substrate. A standby position for the wafer boat is provided below the treatment vessel of the heat treatment system, and a transfer device (transfer mechanism) that transfers substrates to and from the wafer boat is also provided.

[0003] The transport device includes a lift arm that can be raised and lowered vertically using a ball screw or the like, and a base that can rotate the lift arm horizontally. The transport device also allows a substrate support such as a fork to be advanced and retracted from the lift arm. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-277175 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a technique for stably transporting substrates by monitoring the state of a transport device in a heat treatment system. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided a heat treatment system for heat treating a plurality of substrates, comprising: a substrate holder for holding the plurality of substrates; a transport device provided in a loading area where the substrate holder waits and transporting substrates relative to the substrate holder; a control unit for controlling the operation of the transport device; and a reference member installed within the movement range of the transport device in the loading area, wherein the transport device has a guide body for moving parallel to the longitudinal direction of the substrate holder and a detection sensor for detecting the reference member, and the control unit moves the transport device relative to the reference member and recognizes the state of the guide body based on the detection of the reference member by the detection sensor. [Effects of the Invention]

[0007] According to one aspect, the state of the transfer device of the heat treatment system is monitored, thereby enabling stable transfer of substrates. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a side view schematically showing the overall configuration of a heat treatment system according to an embodiment. [Figure 2] 1 is a side cross-sectional view schematically illustrating an example of a heat treatment apparatus of a heat treatment system. [Figure 3] FIG. 10 is a perspective view showing an example of a transport device in a loading area. [Figure 4] Fig. 4(A) is a side view showing a guide body in an undeformed state in the transport device, and Fig. 4(B) is a side view showing a guide body in an undeformed state in the transport device. [Figure 5] 10A and 10B are side views showing the operation of the reference member and the transport device. [Figure 6] 10 is a plan view showing an example of the arrangement of reference members in a loading area. FIG. [Figure 7] 1 is a flowchart showing a heat treatment method including a condition monitoring method. [Figure 8]Fig. 8(A) is a diagram illustrating a reference member according to a modified example and a conveying device for a guide body that is not deformed, and Fig. 8(B) is a diagram illustrating a reference member according to a modified example and a conveying device for a guide body that is deformed. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0010] The heat treatment system 100 performs heat treatment (film formation process) to form a desired film on the surface of each substrate W by heating the substrates W while supplying an appropriate processing gas. To perform the heat treatment, the heat treatment system 100 has a plurality of compartments, such as a processing region 101, a loading region 102, and a carry-in / out region 103, as shown in FIG.

[0011] The processing region 101 is an area where the actual heat treatment is performed on each substrate W, and includes a heat treatment device 1. The loading region 102 is an area where each substrate W is transferred between the heat treatment device 1 and the loading / unloading region 103, and includes a boat operating unit 110, a boat stage 120, a transport device 130, a reference member 140, etc. The loading / unloading region 103 is an area where containers C that contain substrates W, such as FOUPs (Front-Opening Unified Pods), are stored and transported, and includes a mounting table 160 on which the container C is placed, and a storage mechanism (not shown) that transports, waits, loads and unloads multiple containers C, etc.

[0012] 2, the heat treatment apparatus 1 is a vertical apparatus that holds a plurality of substrates W arranged vertically and forms a desired film on the surface of each substrate W by atomic layer deposition (ALD), chemical vapor deposition (CVD), thermal oxidation, or other methods. The substrate W on which a film is formed is not particularly limited, and examples thereof include a semiconductor substrate such as a silicon wafer or a compound semiconductor wafer, or a glass substrate.

[0013] The heat treatment apparatus 1 includes a processing vessel 10 that accommodates each substrate W and performs film formation, a gas supply unit 30 that supplies gas into the processing vessel 10, a gas exhaust unit 40 that exhausts gas from the processing vessel 10, and a temperature-controlled furnace 50 that is disposed around the processing vessel 10. The heat treatment system 100 also includes a control unit 90 that controls each component of the system including the heat treatment apparatus 1.

[0014] The processing vessel 10 is formed in a cylindrical shape and is installed with its axis aligned vertically (up and down). The processing vessel 10 has a double-cylinder structure including an inner cylinder 11 and an outer cylinder 12 that houses the inner cylinder 11. The inner cylinder 11 and the outer cylinder 12 are made of a heat-resistant material such as quartz and are arranged coaxially. The processing vessel 10 is not limited to a double-cylinder structure, and may also have a single-cylinder structure or a multiple-cylinder structure consisting of three or more cylinders.

[0015] The inner cylinder 11 has an open lower end and a ceiling wall at its upper end. The inner cylinder 11 has an inner diameter larger than the diameter of each substrate W. The interior of the inner cylinder 11 forms a processing space P1 in which gas is supplied to each of the accommodated substrates W to form a film. Openings 15 are provided at appropriate circumferential positions of the inner cylinder 11 to allow gas to flow from the processing space P1 to a flow space P2 between the inner cylinder 11 and the outer cylinder 12. The openings 15 may be formed in the ceiling wall of the inner cylinder 11, for example.

[0016] Furthermore, the inner cylinder 11 has a housing portion 13 capable of housing a gas supply nozzle 31 of the gas supply unit 30, at a circumferential position opposite the opening 15. As an example, the housing portion 13 is provided inside a protrusion 14 that protrudes a part of the side wall of the inner cylinder 11 radially outward.

[0017] The outer cylinder 12 has an inner diameter larger than that of the inner cylinder 11 and covers the inner cylinder 11 without contacting it. A flow space P2 formed inside the outer cylinder 12 is continuous with the upper and lateral sides of the inner cylinder 11, and allows the gas that has moved from the opening 15 to flow vertically downward.

[0018] The lower end of the processing vessel 10 is supported by a cylindrical manifold 17 made of stainless steel. The manifold 17 extends along the boundary between the partitioned processing region 101 and loading region 102, connecting the two regions internally. The manifold 17 has a manifold-side flange 17f at its upper end. The manifold-side flange 17f secures and supports an outer-cylinder-side flange 12f formed at the lower end of the outer cylinder 12. A seal member 19 is provided between the outer-cylinder-side flange 12f and the manifold-side flange 17f to airtightly seal the outer cylinder 12 and the manifold 17. The manifold 17 also has an annular support plate 16 on its upper inner wall. The support plate 16 protrudes radially inward from the inner wall to secure and support the lower end of the inner cylinder 11.

[0019] A lid 21 is disposed at the lower end opening of the manifold 17. The lid 21 is configured to be movable in the horizontal and vertical directions by an opening / closing mechanism (not shown) to open and close the lower end opening of the manifold 17 (see also FIG. 1). The lower end of the manifold 17 is provided with a seal member 18 that airtightly closes the lower end opening of the manifold 17 when the lid 21 is closed. After the wafer boat 20 is accommodated inside, the processing vessel 10 and the manifold 17 are sealed inside when the lid 21 is closed.

[0020] The wafer boat 20 is a substrate holder that holds multiple substrates W. The longitudinal direction of the wafer boat 20 is aligned vertically, and multiple shelf plates (not shown) hold the outer edges of each substrate W. When held by the wafer boat 20, the substrates W are lined up at regular intervals along the vertical direction and are supported horizontally relative to one another.

[0021] Furthermore, the heat treatment system 100 includes a rotation unit 23 that rotatably supports the wafer boat 20, and an elevation unit 25 that supports the wafer boat 20 via the rotation unit 23 so that it can move up and down. The rotation unit 23 and the elevation unit 25 constitute a boat operating unit 110 (described later) in the heat treatment system 100 (see also FIG. 1).

[0022] The rotating unit 23 includes a rotation source (not shown), a rotating shaft 24 rotated by the rotation source, and a rotating plate 26 connected to the upper end of the rotating shaft 24. The wafer boat 20 is mounted on the upper surface of the rotating plate 26 via a heat insulating structure 27. The rotating unit 23 rotates the rotating shaft 24 and the rotating plate 26, thereby rotating the heat insulating structure 27 and the wafer boat 20 around a vertical axis.

[0023] The lifting unit 25 has a column 25A extending vertically, an arm 25B that can be raised and lowered relative to the column 25A, and an elevation drive unit (not shown) that raises and lowers the arm 25B. The arm 25B extends horizontally, and its extension end supports the components (wafer boat 20, rotating plate 26, and heat insulating structure 27) above the rotating unit 23. By raising and lowering the arm 25B of the lifting unit 25, the heat processing apparatus 1 raises and lowers the rotating unit 23 and the components above the rotating unit 23 together, thereby inserting and removing the wafer boat 20 into and from the processing vessel 10.

[0024] The gas supply unit 30 includes one or more gas supply nozzles 31 for supplying gas to each substrate W disposed in the processing space P1. Examples of gases supplied by the gas supply unit 30 include a source gas for depositing a precursor on the substrate W, a reaction gas that reacts with the precursor, and a purge gas that purges the processing space P1.

[0025] In the embodiment, the gas supply unit 30 includes two gas supply nozzles 31 (a first gas supply nozzle 31A and a second gas supply nozzle 31B). The first gas supply nozzle 31A supplies a source gas and a purge gas into the processing vessel 10. The second gas supply nozzle 31B supplies a reactive gas into the processing vessel 10. The gas supply unit 30 is not limited to this configuration, and may include a gas supply nozzle 31 for each type of source gas, reactive gas, and purge gas (i.e., three or more). Conversely, the gas supply unit 30 may be configured to supply the source gas, reactive gas, and purge gas through a single gas supply nozzle 31.

[0026] Each gas supply nozzle 31 (first gas supply nozzle 31A, second gas supply nozzle 31B) is a quartz injector tube fixed to the manifold 17. Each gas supply nozzle 31 extends vertically within the inner cylinder 11 and is bent at its lower end into an L-shape, penetrating the inside and outside of the manifold 17. Each gas supply nozzle 31 has a plurality of gas holes 31h arranged at regular intervals in the vertical direction within the inner cylinder 11, and discharges gas horizontally from each gas hole 31h. The intervals between the gas holes 31h are set to be the same as the intervals between the substrates W supported by the wafer boat 20, for example. The vertical positions of each gas hole 31h are set to be midway between the substrates W adjacent to each other in the vertical direction. This allows each gas hole 31h to smoothly supply gas to the gaps between the substrates W.

[0027] The gas supply unit 30 has, outside the processing vessel 10, a plurality of gas supply paths 32 connected to a first gas supply nozzle 31A and a second gas supply nozzle 31B, respectively. The gas supply path 32 connected to the first gas supply nozzle 31A branches off midway and is connected to a source gas source and a purge gas source (not shown). The gas supply path 32 connected to the second gas supply nozzle 31B is connected to a reaction gas source (not shown). Each gas supply path 32 is further equipped with a flow regulator for adjusting the gas flow rate, a valve for opening and closing a flow path within the path, and the like (both not shown) at a midway point leading to the corresponding gas source.

[0028] The gas exhaust unit 40 exhausts gas inside the processing vessel 10 to the outside. Gas supplied by each gas supply nozzle 31 moves from the processing space P1 of the inner cylinder 11 to the flow space P2, and then is exhausted through the gas outlet 41. The gas outlet 41 is formed on the upper sidewall of the manifold 17, above the support plate 16. An exhaust path 42 of the gas exhaust unit 40 is connected to the gas outlet 41. The gas exhaust unit 40 includes, in order from upstream to downstream of the exhaust path 42, a pressure adjustment valve 43 and a vacuum pump 44. The gas exhaust unit 40 sucks gas inside the processing vessel 10 using the vacuum pump 44 and adjusts the flow rate of the exhausted gas using the pressure adjustment valve 43, thereby adjusting the pressure inside the processing vessel 10.

[0029] Furthermore, a temperature sensor 80 is provided inside the processing vessel 10 (for example, in the processing space P1 inside the inner cylinder 11) to detect the temperature inside the processing vessel 10. The temperature sensor 80 has multiple (five in this embodiment) temperature measuring elements 81-85 at different positions in the vertical direction. The multiple temperature measuring elements 81-85 may be thermocouples, resistance temperature detectors, or the like. The temperature sensor 80 transmits the temperatures detected by each of the multiple temperature measuring elements 81-85 to the control unit 90.

[0030] On the other hand, the temperature-controlled furnace 50 covers the entire processing vessel 10 and heats and cools each substrate W accommodated in the processing vessel 10 from the outside. Specifically, the temperature-controlled furnace 50 includes a cylindrical housing 51 having a ceiling and a heater 52 provided inside the housing 51.

[0031] The housing 51 is attached to the upper surface of a base plate 54 located at the boundary between the processing vessel 10 and the manifold 17, and heats the processing vessel 10 housed therein. The housing 51 is installed with a gap between it and the processing vessel 10, and a temperature-controlled space 53 is formed between the processing vessel 10 and the housing 51.

[0032] The housing 51 includes a heat insulating part 51a having a ceiling and covering the entire processing vessel 10, and a reinforcing part 51b that reinforces the heat insulating part 51a on the outer periphery side of the heat insulating part 51a. In order to suppress thermal influence on the outside of the temperature-controlled furnace 50, the outer periphery side of the reinforcing part 51b is covered with a water-cooling jacket (not shown).

[0033] Furthermore, the temperature-controlled furnace 50 includes a cooling unit 60 that circulates a cooling gas such as air through the temperature-controlled space 53 to cool the processing vessel 10 during or after film formation. The cooling unit 60 includes an external supply path 61 and a flow rate regulator 62 that are provided outside the temperature-controlled furnace 50, a supply flow path 63 that is provided in the reinforcing portion 51b, and a plurality of supply holes 64 that are provided in the insulating portion 51a.

[0034] The cooling unit 60 also has an exhaust hole 65 in the ceiling of the housing 51 for discharging air supplied into the temperature-controlled space 53. The exhaust hole 65 is connected to an external exhaust path 66 provided outside the housing 51.

[0035] In the above example, the heat treatment apparatus 1 has been described as an apparatus that supplies a source gas and a reactive gas as processing gases to form a desired film on the surface of each substrate W. However, the heat treatment system 100 is not limited to applying a film forming apparatus as the heat treatment apparatus 1. For example, the heat treatment system 100 may also apply an apparatus that etches a film on the surface of each substrate W or an apparatus that modifies or cleans the surface of each substrate W as the heat treatment apparatus. Furthermore, the heat treatment apparatus may be configured to generate plasma within the processing chamber 10.

[0036] The control unit 90 of the heat treatment apparatus 1 may be a computer having a processor, memory, an input / output interface, a communication interface, etc. The processor may be one or a combination of a central processing unit (CPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a circuit made up of multiple discrete semiconductors, etc. The memory may include a main storage device made up of a semiconductor memory or the like, and an auxiliary storage device made up of a disk, semiconductor memory (flash memory), etc. The memory may be configured by appropriately combining volatile memory and non-volatile memory (e.g., a compact disk, a digital versatile disc (DVD), a hard disk, flash memory, etc.).

[0037] The memory stores a program for operating the heat treatment system 100 and a recipe for heat treatment process conditions, etc. The processor controls each component of the heat treatment system 100 by reading and executing the memory program. In other words, the control unit 90 of the present disclosure is an electronic circuit having a CPU, GPU, ASIC, FPGA, etc., and performs the various control operations described herein by executing instruction codes stored in the memory or by circuit design for a specific application. The control unit may also be configured as a host computer or multiple client computers communicating via a network. The heat treatment system 100 is not limited to a configuration in which the control unit 90 directly controls each device. Instead, it may be configured such that appropriate devices (e.g., the transport device 130) are equipped with dedicated control devices, and the control unit 90 sends control commands to the control devices to control each device.

[0038] 1, the loading area 102 of the heat treatment system 100 is a space formed below the processing area 101. In the loading area 102, the wafer boat 20 is loaded into and unloaded from the processing vessel 10, the substrates W are transported within the loading area 102, and the substrates W are transferred to and from the wafer boat 20 and the vessel C.

[0039] The boat operating unit 110 in the loading area 102 is provided vertically below the processing vessel 10 of the heat treatment apparatus 1. The boat operating unit 110 includes the above-described rotation unit 23 and lifting unit 25 (pillars 25A and arms 25B). The lifting unit 25 lifts the arm 25B under the operation of the lifting drive unit, thereby loading the entire wafer boat 20 mounted on the arm 25B into the processing vessel 10. The lifting unit 25 also lowers the arm 25B under the operation of the lifting drive unit, thereby unloading the entire wafer boat 20 into the space vertically below the processing vessel 10.

[0040] The boat stage 120 allows the wafer boat 20 to wait before or after heat treatment. The heat treatment system 100 transfers and unloads each substrate W to and from the wafer boat 20 while the wafer boat 20 and the heat insulating structure 27 (see FIG. 2) wait on the boat stage 120. Note that although the embodiment is configured to have one boat stage 120 below the processing vessel 10, the heat treatment system 100 may be provided with multiple boat stages 120. For example, the heat treatment system 100 can be configured to transport the wafer boat 20 between different boat stages 120 by a boat transport unit (not shown).

[0041] The transfer device 130 is provided between the boat stage 120 and the carry-in / out area 103 in the loading area 102, and transfers the substrate W. As shown in Fig. 3, the transfer device 130 is configured to be movable in the horizontal direction (X-axis direction) and the vertical direction (Z-axis direction) and to be rotatable about a vertical axis. For example, the transfer device 130 includes a base 131, a movable body 132 provided on the base 131, a turning mechanism 133 provided on the movable body 132, an advancing / retracting mechanism 134 provided on the turning mechanism 133, and a plurality of forks 135 that advance and retreat by the advancing / retracting mechanism 134.

[0042] Base 131 is formed in a rectangular shape that is long in the Y-axis direction in a plan view, and allows upper movable body 132 to move freely in the Y-axis direction. For example, base 131 has a plurality of rails (not shown) that extend in the Y-axis direction, and a plurality of rolling elements (not shown) provided on the lower surface of movable body 132 move along the rails.

[0043] The movable body 132 has an internal horizontal drive unit that rotates a plurality of rolling elements, and moves in the Y-axis direction on the base 131 based on the drive of the horizontal drive unit. The movable body 132 is positioned at a target position in the Y-axis direction based on the control of the control unit 90.

[0044] The turning mechanism 133 is provided on the movable body 132 and turns the advancing / retreating mechanism 134. For example, the turning mechanism 133 includes a turning drive unit provided inside the movable body 132 and a disk to which the advancing / retreating mechanism 134 is fixed and which is rotated by the turning drive unit. The turning mechanism 133 is positioned at a target turning position under the control of the control unit 90. The target turning position is, for example, a position where the multiple forks 135 extend along the X-axis direction (X-axis positive direction, X-axis negative direction).

[0045] The advancing / retreating mechanism 134 has a fixed part that is fixed to the swivel mechanism 133, and an arm 134a that can advance and retreat relative to the fixed part. The arm 134a supports a plurality of forks 135, and allows each fork 135 to advance and retreat when the arm 134a is in an advanced position. When the forks 135 are positioned at the target swivel position by the swivel mechanism 133, the advancing / retreating mechanism 134 advances and retreats each fork 135 in the X-axis direction (positive X-axis direction, negative X-axis direction) via the arm 134a.

[0046] A plurality of forks 135 (five in FIG. 3) are provided on the arm 134a. The number of forks 135 is not particularly limited. When transferring and transporting the substrate W, the advancing / retracting mechanism 134 may simultaneously advance and retract the plurality of forks 135, or may advance and retract only one fork 135. For example, the advancing / retracting mechanism 134 may be configured to selectively execute a first pattern in which only the upper fork 135 advances and retracts, and a second pattern in which the lower four forks 135 advance and retract simultaneously. A spacing adjustment mechanism for adjusting the vertical spacing between the forks 135 may be provided inside the arm 134a.

[0047] The fork 135 has a base 135a fixed to the arm 134a and a pair of claws 135b protruding from the base 135a toward the tip (end). This gives the fork 135 a U-shape in plan view, with an opening toward the tip. The base 135a and the pair of claws 135b are made of a single plate and are flush with and continuous with each other. The base 135a and the pair of claws 135b are sized to correspond to the diameter of the substrate W, and the substrate W is placed on their upper surfaces for transport.

[0048] The fork 135 may have multiple (three) suction pads 135c on its upper surface. Each suction pad 135c is arranged near the opening on the tip end side of the base 135a and at the tip of each claw 135b so as to face the outer periphery of the substrate W. Each suction pad 135c is connected to a flow path provided in the base 135a and the claw 135b, and this flow path is connected to a suction device (not shown). The suction device applies a suction force to each suction pad 135c under the control of the control unit 90, thereby adsorbing the substrate W placed on each suction pad 135c. Note that the means by which the fork 135 holds the substrate W is not limited to suction force, and electrostatic adsorption, a mechanical fixing mechanism, etc. may also be used.

[0049] The fork 135 also includes a detection sensor 136 at the tip of the pair of claws 135b for detecting an object and recognizing its position. The control unit 90 moves the transfer device 130 while monitoring the position (three-dimensional coordinates) of the detection sensor 136 within the loading area 102, and detects an object inside the loading area 102 using the detection sensor 136. For example, the detection sensor 136 detects the presence or absence of a detection target (not shown) provided at a position on the wafer boat 20 for transferring and receiving the substrates W, and transmits the detection result to the control unit 90. The control unit 90 can instruct the wafer boat 20 on the positions for transferring and receiving the substrates W by linking the three-dimensional coordinates mapped as the transfer device 130 moves with information on the presence of the detection target.

[0050] The detection sensor 136 according to the embodiment includes, for example, a light-projecting unit 136a and a light-receiving unit 136b that are arranged opposite each other in the horizontal direction. The light-projecting unit 136a is provided at the tip of one of the pair of claws 135b and emits detection light toward the light-receiving unit 136b. The light-receiving unit 136b is provided at the tip of the other of the pair of claws 135b and receives the detection light emitted by the light-projecting unit 136a. When an object is present between the light-projecting unit 136a and the light-receiving unit 136b, the light-receiving unit 136b transmits information (non-detection information) to the control unit 90 indicating that the detection light emitted by the light-projecting unit 136a has been blocked. As a result, the control unit 90 recognizes the three-dimensional coordinates at the time the information is received as the position of the object.

[0051] The transport device 130 also has an elevator mechanism 137 that raises and lowers each fork 135 in the vertical direction within the loading area 102. The elevator mechanism 137 may have any suitable configuration, such as a ball screw mechanism or a rack-and-pinion gear mechanism. The elevator mechanism 137 includes a guide body 137a that extends vertically within the loading area 102, and an elevator drive unit 137b that raises and lowers the transport device 130 in the vertical direction while being guided by the guide body 137a.

[0052] The guide body 137a extends vertically in the loading area 102 to enable the transfer device 130 to transfer each substrate W to and from the wafer boat 20, which is long in the vertical direction. For example, both ends of the guide body 137a are fixed to the ceiling and floor of the loading area 102, respectively.

[0053] The lifting / lowering drive unit 137b moves each fork 135 parallel to the vertical direction (longitudinal direction) of the wafer boat 20 by moving up and down along the guide body 137a. The lifting / lowering drive unit 137b is connected to the control unit 90 and positions each fork 135 at a target lifting / lowering position under the control of the control unit 90. In FIG. 3, the lifting / lowering drive unit 137b is fixed to one side of the base 131 and is configured to lift and lower the base 131 and the mechanism thereon as a whole. However, the lifting / lowering drive unit 137b is not limited to this configuration, and may be configured to lift and lower the base 131 by rotatably supporting the guide body 137a at an end of the guide body 137a.

[0054] The transport device 130 is not limited to the above configuration, and various devices capable of transporting the substrate W may be applied. For example, the transport device 130 may be an articulated device having multiple arms and multiple joints to move a fork.

[0055] 1, the reference member 140 in the loading area 102 is a member used as an index when monitoring the state of the guide body 137a of the transport device 130. This reference member 140 will be described in detail later.

[0056] The loading / unloading area 103 of the heat treatment system 100 is provided adjacent to the loading area 102. The loading / unloading area 103 may be, for example, compliant with the FIMS (Front-opening Interface Mechanical Standards) system, which is a mechanical standard. The loading area 102 and the loading / unloading area 103 are separated by a partition wall 104. A mounting table 160 in the loading / unloading area 103 is provided at a position corresponding to a port 161 (see FIG. 6 ) provided in the partition wall 104, allowing a container C to be set therein. The port 161 is configured to be openable and closable between the loading area 102 and the loading / unloading area 103, and when open, exposes the container C set on the mounting table 160 to the loading area 102.

[0057] The storage mechanism in the loading / unloading area 103 has multiple containers C waiting in the vertical direction, for example. The storage mechanism can transport the stored containers C and set them on the mounting table 160. The storage mechanism also has a load port (not shown) that loads and unloads the containers C into and out of the loading / unloading area 103.

[0058] In the heat treatment system 100 described above, after heat treatment in the processing region 101, the wafer boat 20 carrying high-temperature substrates W is unloaded into the loading region 102, causing a rise in temperature within the loading region 102. As described above, the guide body 137a extends elongatedly in the vertical direction of the loading region 102. In this case, the guide body 137a may be deformed due to a difference in thermal expansion caused by a rise in temperature within the loading region 102.

[0059] For example, the control unit 90 of the heat treatment system 100 instructs the transfer device 130 on the positions (three-dimensional coordinates) for transferring and receiving the substrates W with respect to the wafer boat 20 at room temperature before the heat treatment device 1 is put into operation. At this time, the guide body 137a does not thermally expand, as shown in FIG. 4(A), and therefore extends linearly in the vertical direction. Therefore, the transfer device 130 can stably move up and down in the vertical direction. The control unit 90 recognizes values ​​at which the X-axis coordinate and the Y-axis coordinate become approximately constant along the vertical direction for the taught positions for transferring and receiving the substrates W with respect to the wafer boat 20.

[0060] In contrast, in the loading area 102 of the heat treatment system 100, the temperature in the space rises due to the thermal effect of each substrate W after heat treatment, and the guide body 137a thermally expands and deforms, as shown in Fig. 4(B). In this case, deformation occurs at the base of the structure supporting each fork 135, and the entire transfer device 130 is affected by the deformation. For example, the transfer device 130 may transfer and receive substrates W in an inclined position (facing up or down) relative to the wafer boat 20.

[0061] In particular, in a configuration in which the base 131, the movable body 132, the turning mechanism 133, the advancing / retracting mechanism 134, and the forks 135 are located on the X-axis side of the guide body 137a, the guide body 137a is subject to loads in the X-axis direction from each component, and is therefore prone to deformation along the X-axis direction. However, the degree of deformation of the guide body 137a (such as the amount of deformation and the shape of the deformation) is difficult to predict because it is affected by factors such as the temperature and the position of the transport device 130. Furthermore, in the heat treatment system 100, heat accumulates in the loading area 102 as multiple heat treatments are performed, and therefore the degree of deformation of the guide body 137a may change with each heat treatment.

[0062] Therefore, the heat treatment system 100 according to the embodiment is configured to install a reference member 140 within the movement range of the fork 135 of the transfer device 130, and to recognize the degree of deformation of the guide body 137a of the transfer device 130 relative to the reference member 140. This enables the heat treatment system 100 to take various measures depending on the degree of deformation of the guide body 137a.

[0063] 5, the reference member 140 has a base 141 extending in the vertical direction and a plurality of protrusions 142 protruding laterally from the base 141. The plurality of protrusions 142 are arranged at equal intervals along the vertical direction (a direction parallel to the longitudinal direction of the wafer boat 20). It is desirable that each of the protrusions 142 has three or more protrusions 142 (at the upper end, the lower end, and an intermediate portion), but the number is not particularly limited. The base 141 and the plurality of protrusions 142 are preferably made of a material with a low thermal expansion coefficient, such as quartz, stainless steel, silicon carbide, silicon nitride, or a low-thermal expansion metal (Invar).

[0064] In order to increase rigidity, the base body 141 is formed in a columnar shape that is thicker (or thicker) than the guide body 137a. The protruding lengths of the protruding portions 142 from the base body 141 are set to be uniform. The protruding lengths of the protruding portions 142 are not particularly limited as long as the forks 135 of the conveying device 130 can reach them. Furthermore, each protruding portion 142 is formed to a size (thickness) that allows it to fit between a pair of claws 135b of the conveying device 130 (forks 135).

[0065] Each protrusion 142 is provided at a height position corresponding to at least the wafer boat 20 when placed on the boat stage 120. For example, the uppermost protrusion 142 of each protrusion 142 is installed so as to be positioned vertically higher than the uppermost substrate W of the substrates W in the wafer boat 20. Similarly, the lowermost protrusion 142 of each protrusion 142 is installed so as to be positioned vertically lower than the lowermost substrate W of the substrates W in the wafer boat 20.

[0066] When checking for deformation of the guide body 137a, the control unit 90 moves the transport device 130 to a position where the forks 135 face the reference member 140. Then, the control unit 90 operates the transport device 130 so that it gradually approaches each protrusion 142 while repeatedly moving up and down. When the detection sensor 136 of the forks 135 detects the protrusion end of each protrusion 142, the control unit 90 maps the three-dimensional coordinates. This enables the control unit 90 to plot (capture) the shape of the guide body 137a based on the positions of the protrusion ends of each protrusion 142 on the reference member 140.

[0067] Specifically, the control unit 90 controls the transport device 130 to repeat the following operations (a) to (d), while causing the detection sensor 136 to perform detection. (a) At the first height position, the fork 135 is slid horizontally by a certain horizontal pitch (for example, 0.1 mm) until it approaches the protrusion 142. (b) The fork 135 is lowered vertically downward from the first height position by a certain vertical length to be placed at the second height position. (c) At the second height position, the fork 135 is slid horizontally by a certain horizontal pitch to approach the protrusion 142. (d) The fork 135 is raised vertically upward from the second height position by a certain vertical length to be placed at the first height position.

[0068] In the above operation, the first height position and the second height position are set in a range longer than the vertical length of the wafer boat 20 placed on the boat stage 120. The horizontal pitch of the forks 135 may be set arbitrarily, for example, in the range of about 0.5 mm to 2 mm.

[0069] While the above operations (a) to (d) are being repeatedly performed, the detection light emitted from the light-emitting portion 136a of the detection sensor 136 toward the light-receiving portion 136b is blocked when it hits a protrusion 142. The control portion 90 maps (stores) the three-dimensional coordinates of each protrusion 142 that blocks the detection sensor 136.

[0070] The installation position of the reference member 140 in the loading area 102 is not particularly limited as long as it is within the reach of the fork 135. For example, as shown by the solid line in FIG. 6, the reference member 140 may be installed adjacent to the boat stage 120. Alternatively, as shown by the dotted line in FIG. 6, the reference member 140 may be installed adjacent to the port 161 in the partition wall 104. This position is on the opposite side of the guide body 137a from the wafer boat 20, and is therefore less susceptible to the heat of the substrates W. The reference member 140 thus arranged in the X-axis direction of the transport device 130 functions as an indicator for detecting deformation of the guide body 137a along the X-axis direction.

[0071] Furthermore, the reference member 140 may be disposed at a position different from the X-axis direction of the transport device 130. For example, as shown by the dotted line in Fig. 6, the reference member 140 may be installed in the Y-axis direction of the transport device 130. This allows the control unit 90 to detect deformation of the guide body 137a in a direction different from the X-axis direction (Y-axis direction).

[0072] The heat treatment system 100 according to the embodiment is basically configured as described above, and its operation (heat treatment method including a state monitoring method) will be described below with reference to the flowchart of FIG.

[0073] 7 in order to execute steps S101 to S111 in Fig. 7. Note that the positions for transferring and receiving the substrates W to and from the wafer boat 20, which are required for the transfer by the transfer device 130, and the positions for transferring and receiving the substrates W to and from the container C on the mounting table 160, etc. are instructed before the heat treatment method is executed.

[0074] The transfer device 130 operates based on commands from the control unit 90, removes the substrates W stored in the container C, and places the substrates W on the wafer boat 20 waiting on the boat stage 120 (step S101). At this time, the transfer device 130 may adopt a first pattern in which one fork 135 transfers the substrates W one by one, but by adopting a second pattern in which multiple forks 135 transfer multiple substrates W, each substrate W can be transferred efficiently.

[0075] After the substrates W are placed vertically on the wafer boat 20, the boat operating unit 110 raises the wafer boat 20 and loads the wafer boat 20 into the processing chamber 10 of the heat processing apparatus 1 (step S102). After the wafer boat 20 is loaded, the heat processing apparatus 1 closes the lower end of the manifold 17 with the lid 21.

[0076] Thereafter, the heat treatment apparatus 1 performs heat treatment (film formation process) on each substrate W in the processing chamber 10 (step S103). In the film formation process, the gas supply unit 30 supplies processing gas into the processing chamber 10, the gas exhaust unit 40 exhausts the gas inside the processing chamber 10, and the temperature-controlled furnace 50 heats each substrate W to a target temperature. As a result, a film having a desired film thickness is formed on each substrate W.

[0077] After the heat treatment in the heat treatment apparatus 1 is completed, the heat treatment apparatus 1 opens the lid 21, and the boat operating unit 110 lowers the wafer boat 20 to unload the wafer boat 20 from the processing vessel 10 (step S104). The unloaded wafer boat 20 is placed on the boat stage 120.

[0078] Next, the heat treatment system 100 waits for a set time, thereby performing a cooling process to cool the wafer boat 20 and each substrate W (step S105). By performing this cooling process, the temperature of each substrate W decreases, and the temperature in the loading area 102 also decreases to some extent. The loading area 102 may be provided with an internal cooling device that promotes a decrease in the temperature of each substrate W during cleaning processing or the like.

[0079] After the cooling process, the control unit 90 performs a state confirmation process to confirm the state of the transfer device 130 (guide body 137a) using the transfer device 130 and the reference member 140 (step S106). That is, the state confirmation process is performed after the heat treatment by the heat treatment device 1 and before the transfer device 130 removes the substrates W from the wafer boat 20.

[0080] In the state confirmation process, the transport device 130 moves to a position facing the reference member 140 as described above, and repeatedly moves up and down in the vertical direction while bringing the forks 135 horizontally closer to the reference member 140. Preferably, the transport device 130 moves the forks 135 using a first pattern in which only one fork 135 advances. The control unit 90 maps the positions of the protrusions 142 of the reference member 140 by detecting the presence or absence of the protrusion ends of the protrusions 142 using the detection sensor 136 during the movement of the forks 135. For example, if the vertically intermediate portion of the guide body 137a is curved in the negative direction of the X-axis, the control unit 90 recognizes positions of the protrusions 142 near the top and the protrusions 142 near the bottom that are farther away in the negative direction of the X-axis through mapping using the detection sensor 136. Meanwhile, the control unit 90 recognizes positions of the protrusions 142 near the vertically intermediate portion that are closer to the positive direction of the X-axis. Based on such detection results, the control unit 90 can grasp (estimate) the degree of deformation of the guide body 137a.

[0081] After performing the state confirmation process, the control unit 90 determines whether or not there is a problem with the transport of the substrate W (step S107). For example, the control unit 90 has a threshold value for comparing the degree of deformation, and determines whether or not the degree of deformation of the guide body 137a is equal to or greater than the threshold value. If it is equal to or greater than the threshold value, it means that the degree of deformation of the guide body 137a is causing a problem with the transport of the substrate W, and if it is less than the threshold value, it can be considered that the deformation of the guide body 137a is small (or not deformed). If there is a problem with the transport of the substrate W (step S107: YES), the control unit 90 proceeds to step S108, and if there is no problem with the transport of the substrate W, the control unit 90 proceeds to step S111.

[0082] In step S108, the control unit 90 determines whether the number of retries for the state confirmation process has reached an upper limit. If this determination shows that the number of retries has reached the upper limit, it can be recognized that the deformation of the guide body 137a has not been resolved even after performing the state confirmation process multiple times. If the number of retries has reached the upper limit (step S108: YES), the control unit 90 proceeds to step S109, and if the number of retries has not reached the upper limit (step S108: YES), the control unit 90 proceeds to step S110.

[0083] In step S109, the control unit 90 recognizes that an abnormality has occurred in the transport device 130 and notifies the user of the error via the user interface. The error may be accompanied by information indicating that an abnormality has occurred in the transport device 130, the degree of deformation of the guide body 137a, etc. Based on the content of the confirmed error, the user can determine whether to continue transport by the transport device 130 or stop processing, and take appropriate action. Note that the control unit 90 may automatically stop the operation of the heat treatment system 100 together with notifying the error when an abnormality has occurred in the transport device 130.

[0084] On the other hand, if the number of retries has not reached the upper limit, the control unit 90 increments the number of retries for the process and waits for a preset period to lower the temperature in the loading area 102 (step S110). The loading area 102 may be cooled by a cooling device during standby. When the period ends, the control unit 90 returns to step S106 and performs the status confirmation process again.

[0085] Furthermore, if there is no problem with the transport of the substrates W in step S107, the transfer device 130 performs an operation of removing the substrates W from the wafer boat 20 and storing each substrate W in a container C waiting on the mounting table 160 (step S111). At this time, the transfer device 130 can stably move up and down in the vertical direction along the guide body 137a, and can smoothly remove each substrate W from the wafer boat 20. Therefore, the transfer device 130 can store each substrate W in the container C with high accuracy.

[0086] Steps S106 to S111 of the heat treatment method described above correspond to the state monitoring method according to the embodiment. In this way, the state monitoring method can effectively monitor the state of the transport device 130 by determining the degree of deformation of the guide body 137a of the transport device 130 using the reference member 140 installed in the loading area 102. Furthermore, the state monitoring method can prevent poor holding of the substrate W when transporting the substrate W after heat treatment by recognizing the degree of deformation of the guide body 137a after heat treatment of each substrate W and before transporting the substrate W.

[0087] The heat treatment system 100 is not limited to the above embodiment and may be modified in various ways. For example, the heat treatment system 100 may perform the status check process for the transfer device 130 even when the temperature in the loading area 102 is not high (e.g., room temperature). Deformation of the guide body 137a may also occur due to thermal contraction, deterioration over time, or other disturbances. Therefore, the heat treatment system 100 can appropriately manage the status of the transfer device 130 by performing the status check process periodically or at any time.

[0088] 8(A) and 8(B), the heat treatment system 100 may employ a reference member 140A having a flat protrusion 143 extending horizontally, which is detected by the detection sensor 136 of the transfer device 130. This allows the heat treatment system 100 to recognize deformation in the Y-axis direction in addition to deformation in the X-axis direction, depending on the detection time of the protrusion 143 by the detection sensor 136.

[0089] Specifically, when guide body 137a is not deformed in the Y-axis direction, each of claws 135b of fork 135 of conveyance device 130 is aligned horizontally, as shown in Fig. 8(A). Therefore, when conveyance device 130 is raised or lowered, detection sensor 136 provided on each of claws 135b detects protrusion 143 in a short detection time. Control unit 90 stores the detection time of protrusion 143 when guide body 137a is not deformed in the Y-axis direction as a reference period.

[0090] On the other hand, when the guide body 137a is deformed in the Y-axis direction, as shown in FIG. 8B, the claws 135b of the fork 135 of the conveyance device 130 are aligned in a tilted state relative to the horizontal. Therefore, when the conveyance device 130 is raised or lowered, the detection sensors 136 provided on the claws 135b detect the protrusions 143 for a long detection time. The control unit 90 can estimate the degree of tilt of each claw 135b, in other words, the degree of deformation of the guide body 137a, by comparing this detection time with a reference time. Therefore, the control unit 90 can simultaneously recognize the degree of deformation of the guide body 137a in both the X-axis direction and the Y-axis direction by performing a state confirmation process for the conveyance device 130 using a single reference member 140A.

[0091] The technical ideas and effects of the present disclosure explained in the above embodiments will be described below.

[0092] A first aspect of the present disclosure is a heat treatment system 100 for heat treating multiple substrates W, comprising: a substrate holder (wafer boat 20) for holding multiple substrates W; a transport device 130 provided in a loading area 102 where the substrate holder waits and transporting the substrates W to the substrate holder; a control unit 90 for controlling the operation of the transport device 130; and a reference member 140 installed within the movement range of the transport device 130 in the loading area 102, wherein the transport device 130 has a guide body 137a for moving parallel to the longitudinal direction of the substrate holder and a detection sensor 136 for detecting the reference member 140, and the control unit 90 moves the transport device 130 relative to the reference member 140 and recognizes the state of the guide body 137a based on the detection of the reference member 140 by the detection sensor 136.

[0093] As described above, the heat treatment system 100 can effectively monitor the state of the transfer device 130 by using the detection sensor 136 to detect the reference member 140 during movement of the transfer device 130. This allows the transfer device 130 to stably transfer the substrates W by suppressing the occurrence of a problem in the transfer of the substrates W due to deformation of the guide body 137a. For example, the transfer device 130 can accurately transfer and receive the substrates W to and from the substrate holder (wafer boat 20).

[0094] The heat treatment system 100 also includes a heat treatment apparatus 1 that accommodates a substrate holder (wafer boat 20) that holds a plurality of substrates W and performs heat treatment on the plurality of substrates W, and the control unit 90 recognizes the state of the guide body 137a after the heat treatment by the heat treatment apparatus 1 and before the plurality of substrates W are removed from the substrate holder by the transfer device 130. This allows the heat treatment system 100 to reliably recognize the state of the guide body 137a before removing the substrates W after the heat treatment.

[0095] Furthermore, when recognizing the state of the guide body 137a, the control unit 90 estimates the shape of the guide body 137a based on the detection result of the detection sensor 136, determines whether or not there is an impediment to the transport of the substrates W, and if there is an impediment to the transport of the multiple substrates W, waits for the transport of the multiple substrates W, and operates the transport device 130 to transport the multiple substrates W if there is no impediment to the transport of the multiple substrates W. This allows the heat treatment system 100 to stably transport the substrates W in a state in which deformation of the guide body 137a is suppressed (or in a state in which the guide body 137a is not deformed).

[0096] Furthermore, when moving the conveying device 130 relative to the reference member 140 to recognize the state of the guide body 137a, the control unit 90 performs detection using the detection sensor 136 while repeating the following operations: sliding the conveying device 130 by a constant horizontal pitch at the first height position, lowering the conveying device 130 by a constant vertical length from the first height position to place it at a second height position, sliding the conveying device 130 by a constant horizontal pitch at the second height position, and raising the conveying device 130 by a constant vertical length from the second height position to place it at the first height position. This allows the control unit 90 to accurately recognize the degree of deformation of the guide body 137a by the detection of the reference member 140 by the detection sensor 136.

[0097] Furthermore, the transfer device 130 has a fork 135 capable of holding and transferring a substrate W at a position closer to the substrate holder (wafer boat 20) than the guide body 137a, and the reference member 140 is installed at a position adjacent to the substrate holder or at a position on the opposite side of the substrate holder across the guide body 137a. This allows the heat treatment system 100 to accurately recognize, through detection by the detection sensor 136, the shape of the guide body 137a deformed in a direction approaching or moving away from the substrate holder due to the load of the transfer device 130.

[0098] The reference member 140 has a plurality of protrusions 142 arranged in a direction parallel to the longitudinal direction of the substrate holder (wafer boat 20). This allows the detection sensor 136 of the transfer device 130 to discretely detect the protruding ends of the protrusions 142, thereby allowing the control unit 90 to easily recognize the degree of deformation of the guide body 137a.

[0099] The reference member 140 is formed of any of quartz, stainless steel, silicon carbide, silicon nitride, and low-thermal expansion metal, which prevents the reference member 140 from being deformed by heat and allows it to be appropriately used for monitoring the state of the transport device 130.

[0100] A second aspect of the present disclosure is a state monitoring method for monitoring the state of a transfer device 130 of a heat treatment system 100 that heat treats multiple substrates W held by a substrate holder (wafer boat 20), wherein a reference member 140 is installed within the movement range of the transfer device 130 in a loading area 102 where the substrate holder waits, and the transfer device 130 has a guide body 137a for moving parallel to the longitudinal direction of the substrate holder and a detection sensor 136 for detecting the reference member 140, and is configured to be provided in the loading area 102 to transfer the substrates W relative to the substrate holder, and the state monitoring method includes the steps of: (a) moving the transfer device 130 relative to the reference member 140 and detecting the reference member 140 with the detection sensor 136; and (b) recognizing the state of the guide body 137a based on the position where the reference member 140 is detected in step (a). Even in this case, the state monitoring method can stably transfer the substrates W by monitoring the state of the transfer device 130 of the heat treatment system 100.

[0101] The heat treatment system 100 and the condition monitoring method according to the presently disclosed embodiments are illustrative in all respects and not restrictive. The embodiments may be modified and improved in various ways without departing from the spirit and scope of the appended claims. The features described in the above embodiments may be configured differently and may be combined within a consistent range. [Explanation of symbols]

[0102] 20 wafer boats 90 Control Unit 100 Heat Treatment System 102 Loading Area 130 Transport equipment 136 Detection sensor 137a Guide body 140 Reference member W substrate

Claims

1. A thermal processing system for thermally processing a plurality of substrates, comprising: a substrate holder for holding the plurality of substrates; a transport device provided in a loading area where the substrate holder is on standby, for transporting substrates to the substrate holder; a control unit for controlling the operation of the transport device; a reference member installed within a movement range of the transport device in the loading area, the transport device has a guide body for moving the substrate holder parallel to a longitudinal direction thereof, and a detection sensor for detecting the reference member; the control unit moves the transport device relative to the reference member and recognizes the state of the guide body based on the detection of the reference member by the detection sensor. Heat treatment system.

2. a heat treatment device that accommodates the substrate holder holding the plurality of substrates and performs heat treatment on the plurality of substrates; the control unit recognizes a state of the guide body after the heat treatment by the heat treatment device and before the plurality of substrates are removed from the substrate holder by the transport device. The thermal processing system of claim 1 .

3. the control unit estimates the shape of the guide body based on the detection result of the detection sensor in recognizing the state of the guide body, and determines whether or not there is an obstacle to transporting the substrate; When there is a problem with the transport of the plurality of substrates, waiting for the transport of the plurality of substrates; When there is no problem in transporting the plurality of substrates, the transport device is operated to transport the plurality of substrates. The thermal processing system of claim 2 .

4. When the control unit moves the conveying device relative to the reference member to recognize the state of the guide body, detection by the detection sensor is performed while repeating the following operations: sliding the conveying device by a constant horizontal pitch at a first height position; lowering the conveying device by a constant vertical length from the first height position to place it at a second height position; sliding the conveying device by the constant horizontal pitch at the second height position; and raising the conveying device by the constant vertical length from the second height position to place it at the first height position; The heat treatment system according to any one of claims 1 to 3.

5. the transport device has a fork that is located near the substrate holder with respect to the guide body and is capable of holding and transporting a substrate; The reference member is installed at a position adjacent to the substrate holder or at a position opposite the substrate holder with the guide body interposed therebetween. The heat treatment system according to any one of claims 1 to 3.

6. The reference member has a plurality of protrusions arranged in a direction parallel to the longitudinal direction of the substrate holder. The heat treatment system according to any one of claims 1 to 3.

7. the reference member is formed to include any one of quartz, stainless steel, silicon carbide, silicon nitride, and low thermal expansion metal; The heat treatment system according to any one of claims 1 to 3.

8. 1. A status monitoring method for monitoring a status of a transfer device of a heat treatment system that heat-treats a plurality of substrates held by a substrate holder, comprising: a reference member is installed within a movement range of the transport device in a loading area where the substrate holder is waiting; the transport device has a guide body for moving parallel to a longitudinal direction of the substrate holder and a detection sensor for detecting the reference member, and is configured to be provided in the loading area and transport the substrate relative to the substrate holder; In the condition monitoring method, (a) moving the conveying device relative to the reference member and detecting the reference member with the detection sensor; (b) recognizing the state of the guide body based on the position of the reference member detected in the step (a), Condition monitoring methods.

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