MOUNTING TABLE STRUCTURE, SUBSTRATE PROCESSING APPARATUS, AND METHOD OF CONTROLLING SUBSTRATE PROCESSING APPARATUS

A mounting table structure includes a mounting table on which a substrate is mounted, a refrigerating mechanism configured to cool the substrate, an elevating drive part configured to move the mounting table or the refrigerating mechanism up and down, and at least one contact provided at a position between the refrigerating mechanism and the mounting table which face each other. The refrigerating mechanism and the mounting table are allowed to be brought into contact with each other via the contact by moving the mounting table or the refrigerating mechanism up and down by the elevating drive part.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No. 2021-008954 filed on Jan. 22, 2021, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a mounting table structure, a substrate processing apparatus, and a method of controlling the substrate processing apparatus.

BACKGROUND

Extremely low temperature processing may be required in a substrate processing apparatus, for example, a film forming apparatus. For example, Japanese Laid-open Patent Publication No. 2020-72249 provides a stage device and a processing apparatus that can rotate a mounted substrate in a state in which the substrate is cooled to an extremely low temperature and high cooling performance is provided. In such a processing apparatus, a cooling gas supplied from the outside of the processing apparatus is sufficiently cooled and supplied to a gap between a stage and a refrigerating heat transfer body to cool the stage to an extremely low temperature.

Japanese Patent No. 6559347 proposes a holding device that rotatably holds a target subject to be processed (hereinafter, referred to as “target subject”) while the target subject is cooled in a vacuum chamber, and includes a stage on which the target subject is installed, a rotary driving means that rotatably supports the stage, and a cooling means which cools the stage. In the holding device, the cooling means includes a cooling panel that is disposed in a space below the stage to face a lower surface of the stage with a gap therebetween, a heat transfer shaft that is inserted into a rotating shaft and comes into contact with the lower surface of the cooling panel, and a refrigerator that cools the heat transfer shaft.

SUMMARY

In an indirect method using a refrigerant such as a cooling gas, a partial contact cooling method using a powdery or paste-like heat conductive material, or a cooling method using both of the above methods, it may take some time to control to a target cooling temperature.

The present disclosure provides a mounting table structure, a substrate processing apparatus, and a method of controlling the substrate processing apparatus capable of enhancing the cooling efficiency of a substrate.

One aspect of the present disclosure provides a mounting table structure comprising a mounting table on which a substrate is mounted, a refrigerating mechanism configured to cool the substrate, an elevating drive part configured to move the mounting table or the refrigerating mechanism up and down, and at least one contact provided at a position between the refrigerating mechanism and the mounting table which face each other. The refrigerating mechanism and the mounting table are allowed to be brought into contact with each other via the contact by moving the mounting table or the refrigerating mechanism up and down by the elevating drive part.

DETAILED DESCRIPTION

Hereinafter, embodiments for implementing the present disclosure will be described with reference to the drawings. In each of the accompanying drawings, the same components may be designated by the same reference numerals, and duplicate descriptions thereof may be omitted.

First, an example of a substrate processing apparatus100according to an embodiment of the present disclosure will be described with reference toFIG. 1.FIG. 1is a longitudinal cross-sectional view illustrating an example of the substrate processing apparatus100according to the embodiment. The substrate processing apparatus100illustrated inFIG. 1is, for example, an apparatus that performs desired film formation on a substrate W such as a semiconductor wafer as a substrate to be processed inside a vacuum processing container10that forms a vacuum atmosphere and performs substrate processing with a processing gas. The substrate processing apparatus is a physical vapor deposition (PVD) apparatus.

The substrate processing apparatus100includes a vacuum processing container10, a mounting table20, a refrigerating device30, a rotating device40, a first elevating device77, and a second elevating device78. The mounting table20mounts the substrate W thereon inside the vacuum processing container10. The rotating device40rotates the mounting table20. The first elevating device77moves the mounting table20up and down. The second elevating device78moves the refrigerating device30up and down. The substrate processing apparatus100further includes a controller80that controls various devices such as the refrigerating device30, the rotating device40, the first elevating device77, and the second elevating device78. The substrate processing apparatus100of the illustrated example includes two elevating devices including the first elevating device77that moves the mounting table20up and down and the second elevating device78that moves the refrigerating device30up and down, but the mounting table20and the refrigerating device30may be moved up and down by a common elevating device.

A refrigerator31and a cold link35of the refrigerating device30which will be described below are examples of a refrigerating mechanism for cooling the substrate W. The rotating device40is an example of a rotation drive part that rotates the substrate W. The first elevating device77and the second elevating device78are examples of an elevating drive part for moving a substrate or a refrigerating mechanism up and down.

In the inside of the vacuum processing container10, the mounting table20is located on the lower side, and a plurality of target holders11are fixed above the mounting table2in a state in which they have a predetermined inclination angle θ with respect to a horizontal plane. Then, different types of targets T are mounted on lower surfaces of the target holders11. The inclination angle θ may be 0°, that is, the target holder11may be fixed horizontally.

The vacuum processing container10is configured so that a pressure therein is reduced to a vacuum by operating an exhaust device13such as a vacuum pump. A processing gas (for example, a rare gas such as argon (Ar), krypton (Kr), neon (Ne), or a nitrogen (N2) gas) required for a film formation by sputtering is supplied from a processing gas supply device (not illustrated) to the vacuum processing container10.

An alternating current (AC) voltage or a direct current (DC) voltage from a plasma generation power supply (not illustrated) is applied to the target holder11. When an AC voltage is applied from the plasma generation power supply to the target holder11and the target T, plasma is generated inside the vacuum processing container10, and a rare gas or the like inside the vacuum processing container10is ionized. Then, the target T is sputtered by an ionized rare gas element or the like. Atoms or molecules of the sputtered target T are deposited on a surface of the substrate W held on the mounting table20to face the target T.

It is possible to adjust an incident angle at which the sputtered particles sputtered from the target T are incident on the substrate W by inclining the target T with respect to the substrate W, and thus it is possible to improve the in-plane uniformity of a film thickness of a magnetic film or the like formed on the substrate W. Even when each of the target holders11is installed at the same inclination angle θ inside the vacuum processing container10, the mounting table20is moved up and down to change a distance t1between the target T and the substrate W, and thus the incident angle of the sputtered particles on the substrate W can be changed. Therefore, the mounting table20is controlled to move up and down so that the distance t1suitable for each of the targets T is set for each of the targets T to be applied.

The number of targets T is not particularly limited, but from the viewpoint that different films formed of different materials can be sequentially formed by one substrate processing apparatus100, preferably, a plurality of different targets T are present inside the vacuum processing container10.

The refrigerating device30includes the refrigerator31and the cold link35, and the cold link35is stacked on the refrigerator31. A plurality of contacts21aare provided on the cold link35of the refrigerating device30, and the mounting table20is disposed via the plurality of contacts21a. The refrigerator31holds the cold link35and can cool an upper surface of the cold link35to an extremely low temperature of, for example, −30° C. or lower to about −200° C. From the viewpoint of cooling capacity, the refrigerator31preferably uses a Gifford-McMahon (GM) cycle.

The cold link35is fixed on the refrigerator31, and an upper portion thereof is accommodated inside the vacuum processing container10. The cold link35is made of copper (Cu) or the like having high thermal conductivity, and an exterior thereof is substantially cylindrical. The refrigerator31and the cold link35are disposed so that centers thereof coincide with a central axis CL of the mounting table20.

A refrigerant supply flow path51and a refrigerant discharge flow path52are disposed inside the cold link35and the refrigerator31. The refrigerant supply flow path51supplies a refrigerant, which is a heat transfer gas, between the cold link35and the mounting table20. The refrigerant discharge flow path52discharges the refrigerant of which temperature is raised by heat transfer from the mounting table20. The refrigerant supply flow path51and the refrigerant discharge flow path52are examples of flow paths provided in a refrigerating mechanism to supply a temperature control medium such as a refrigerant.

The refrigerant supply flow path51and the refrigerant discharge flow path52are respectively fixed to connection fixing parts31aand31bon a wall surface of the refrigerator31. The refrigerant supply flow path51and the refrigerant discharge flow path52are examples of flow paths for supplying the temperature control medium provided in the refrigerating device30.

A temperature control refrigerant (for example, a first cooling gas) is supplied from a refrigerant supply device (not illustrated) and flows through the refrigerant supply flow path51. Distal ends of the refrigerant supply flow path51and the refrigerant discharge flow path52open in an upper surface of the cold link35, and the first cooling gas is supplied to a space in which a spring26is disposed between the cold link35and the mounting table20. As the first cooling gas supplied to the space in which the spring26is disposed, helium (He) gas having high thermal conductivity is preferably used. As the first cooling gas, an inert gas may be used so that the spring26and the like in the space do not corrode. Thus, the thermal conductivity of the space between the cold link35and the mounting table20can be increased, and cooling efficiency of the substrate W can be enhanced.

The refrigerant discharged from the space in which the spring26is disposed flows through the refrigerant discharge flow path52and is discharged to a refrigerant discharge device (not illustrated). The refrigerant supply flow path51and the refrigerant discharge flow path52may be formed by the same flow path.

The plurality of contacts21aare provided on the side of the cold link35of the refrigerating device30. The plurality of contacts21aare respectively connected to a plurality of springs26and are mounted to face the mounting table20. The plurality of springs26may be spiral-shaped springs such as compression coil springs. The spring26is an example of an elastic body. The contact21ais made of copper (Cu) having high thermal conductivity. However, it may be configured of any material having high thermal conductivity.

The mounting table20has a structure in which an upper mounting part25on which the substrate W is mounted and a lower contact21bare stacked, and the mounting part25and the contact21bare formed of copper (Cu) having high thermal conductivity. However, the mounting part25and the contact21bmay be formed of any material having high thermal conductivity. The mounting part25includes an electrostatic chuck, and the electrostatic chuck has a chuck electrode32embedded in a dielectric film. A predetermined potential is applied to the chuck electrode32via a wiring33. With such a configuration, the substrate W can be suctioned by the electrostatic chuck, and the substrate W can be held on an upper surface of the mounting table20.

In the present embodiment, the plurality of contacts21adisposed on the side of the cold link35of the refrigerating device30, and the contact21bdisposed on the side of the mounting table20are provided. The contact21aand the contact21bcan be brought into contact with each other or separated from each other by up and down movement due to at least one of the first elevating device77that moves the mounting table20up and down and the second elevating device78that moves the refrigerating device30up and down. That is, the cold link35of the refrigerating device30and the mounting table20can be brought into contact with each other via the plurality of contacts21aand the contact21b.

The mounting table20is supported by an outer cylinder63. The outer cylinder63is disposed to cover an outer peripheral surface of an upper portion of the cold link35, and an upper portion thereof enters the inside of the vacuum processing container10and supports the mounting table20inside the vacuum processing container10. The outer cylinder63has a cylindrical part61having an inner diameter slightly larger than an outer diameter of the cold link35, and a flange part62extending from the lower surface of the cylindrical part61in an outer diameter direction, and the cylindrical part61directly supports the mounting table20. The cylindrical part61and the flange part62are formed of a metal such as stainless steel.

A heat insulating member64is connected to a lower surface of the flange part62. The heat insulating member64has a substantially cylindrical shape that extends coaxially with the flange part62and is fixed to the lower surface of the flange part62. The heat insulating member64is made of a ceramic such as alumina. A magnetic fluid sealing part69is provided on a lower surface of the heat insulating member64.

The magnetic fluid sealing part69includes a rotating part65, an inner fixing part66, an outer fixing part67, and a heating source68. The rotating part65has a substantially cylindrical shape that extends coaxially with the heat insulating member64and is fixed to the lower surface of the heat insulating member64. In other words, the rotating part65is connected to the outer cylinder63via the heat insulating member64. With such a configuration, the heat transfer of cold and heat of the outer cylinder63to the rotating part65is blocked by the heat insulating member64, and it is possible to prevent the temperature of a magnetic fluid of the magnetic fluid sealing part69from being lowered, to prevent deterioration of sealing performance, and to suppress the occurrence of dew condensation.

The inner fixing part66is provided between the cold link35and the rotating part65via a magnetic fluid. The inner fixing part66has a substantially cylindrical shape in which an inner diameter thereof is larger than an outer diameter of the cold link35and an outer diameter thereof is smaller than an inner diameter of the rotating part65. The outer fixing part67is provided outside the rotating part65via a magnetic fluid. The outer fixing part67has a substantially cylindrical shape in which an inner diameter thereof is larger than an outer diameter of the rotating part65. The heating source68is embedded inside the inner fixing part66and heats the entire magnetic fluid sealing part69. With such a configuration, it is possible to prevent the temperature of the magnetic fluid of the magnetic fluid sealing part69from being lowered, to prevent deterioration of the sealing performance, and to suppress the occurrence of dew condensation. With such a configuration, in the magnetic fluid sealing part69, the rotating part65is rotatable in a state in which it is airtight with respect to the inner fixing part66and the outer fixing part67. That is, the outer cylinder63is rotatably supported via the magnetic fluid sealing part69.

A substantially cylindrical bellows75is provided between an upper surface of the outer fixing part67and a lower surface of the vacuum processing container10. The bellows75is a metal bellows structure that can be expanded and contracted in a vertical direction. The bellows75surrounds an upper portion of the cold link35, a lower portion of the outer cylinder63, and the heat insulating member64, and separates an internal space of the vacuum processing container10capable of being decompressed and an external space of the vacuum processing container10from each other.

A slip ring73is provided below the magnetic fluid sealing part69. The slip ring73has a rotating body71including a metal ring, and a fixed body72including a brush. The rotating body71has a substantially cylindrical shape that extends coaxially with the rotating part65of the magnetic fluid sealing part69and is fixed to a lower surface of the rotating part65. The fixed body72has a substantially cylindrical shape in which an inner diameter thereof is slightly larger than an outer diameter of the rotating body71. The slip ring73is electrically connected to a DC power supply (not illustrated), and electric power supplied from the DC power supply is supplied to the wiring33via the brush of the fixed body72and the metal ring of the rotating body71. With such a configuration, it is possible to apply a potential to the chuck electrode from the DC power supply without causing twisting or the like in the wiring33. The rotating body71constituting the slip ring73is mounted in the rotating device40. The slip ring73may have a structure other than the brush structure and may have, for example, a non-contact power supply structure, a structure that is mercury-free or has a conductive liquid, or the like.

The rotating device40is a direct drive motor having a rotor41and a stator45. The rotor41has a substantially cylindrical shape that extends coaxially with the rotating body71of the slip ring73and is fixed to the rotating body71. The stator45has a substantially cylindrical shape in which an inner diameter thereof is larger than an outer diameter of the rotor41. With such a configuration, when the rotor41rotates, the rotating body71, the rotating part65, the outer cylinder63, and the mounting table20rotate in an X3 direction relative to the cold link35. The rotating device may have a form other than the direct drive motor, or may have a form including a servomotor and a transmission belt.

Further, a heat insulating body74having a vacuum heat insulating double structure is provided around the refrigerator31and the cold link35. In the illustrated example, the heat insulating body74is provided between the refrigerator31and the rotor41and between a lower portion of the cold link35and the rotor41. With such a configuration, it is possible to suppress the heat transfer of cold and heat of the refrigerator31and the cold link35to the rotor41.

Further, the refrigerator31is fixed to an upper surface of a first support70A which is mounted in the second elevating device78to be movable up and down. Meanwhile, the rotating device40and the heat insulating body74are fixed to an upper surface of a second support70B which is mounted in the first elevating device77to be movable up and down. Additionally, a substantially cylindrical bellows76surrounding the refrigerator31is provided between the upper surface of the first support70A and a lower surface of the second support70B. Like the bellows75, the bellows76is also a metal bellows structure that can be expanded and contracted in the vertical direction.

A second cooling gas supply pipe34for supplying a second cooling gas is provided in the mounting table20. The second cooling gas supply pipe34passes through the mounting part25and supplies the second cooling gas such as He gas between a lower surface of the substrate W and an upper surface of the mounting part25from a gas hole34a. The second cooling gas may be a gas different from the first cooling gas flowing through the refrigerant supply flow path51or may be the same gas. As the second cooling gas, an inert gas may be used. As a result, the thermal conductivity of the space between the lower surface of the substrate W and the upper surface of the mounting part25can be increased, and the cooling efficiency of the substrate W can be enhanced.

The controller80is configured as a computer. The controller80includes a central processing unit (CPU), a main storage device, an auxiliary storage device, an input and output interface, and a communication interface which are connected to each other by a connection bus. The main storage device and the auxiliary storage device are computer-readable recording media.

The CPU performs control of the entire controller80. For example, the CPU executably expands a program stored in the auxiliary storage device in a work area of the main storage device and performs control of peripheral devices through execution of the program, thereby providing a function suitable for a predetermined purpose. The main storage device stores a computer program executed by the CPU, data processed by the CPU, and the like. The main storage device includes, for example, a flash memory, a random access memory (RAM), and a read only memory (ROM). The auxiliary storage device stores various programs and various types of data in a readable and writable recording medium. The auxiliary storage device is a silicon disk including a non-volatile semiconductor memory, a hard disk drive (HDD) device, a solid state drive device, or the like. Further, the auxiliary storage device may be a compact disc (CD), a digital versatile disc (DVD), a Blu-ray disc (BD), a universal serial bus (USB) memory, an secure digital (SD) memory card or the like as a detachable and attachable recording medium. The communication interface is an interface with a network connected to the controller80. The input and output interface is an interface for inputting and outputting data between the controller80and a device connected to the controller80, and examples thereof include a keyboard and a touch panel. The controller80receives an operation instruction or the like from an operator, who operates an input device, via the input and output interface. The controller80controls operations of various peripheral devices. These peripheral devices include the refrigerating device30, the rotating device40, the first elevating device77, the second elevating device78, and the like.

As described above, a mounting table structure of the substrate processing apparatus100includes the mounting table20on which the substrate W is placed, a refrigerating mechanism that cools the substrate W, an elevating drive part that moves the mounting table20or the refrigerating mechanism up and down, and contacts provided at positions on the refrigerating mechanism and the mounting table20which face each other, and is configured so that the refrigerating mechanism and the mounting table20can be brought into contact with each other via the contacts by the up and down movement of the mounting table20or the refrigerating mechanism due to the elevating drive part.

[Direct Contact by Contact]

Next, the periphery of the contact of the mounting table structure according to the embodiment will be described with reference toFIGS. 2A and 2B.FIGS. 2A and 2Bare diagrams illustrating an example of the periphery of the contact of the mounting table structure according to the embodiment.

Among the constituents of the substrate processing apparatus100ofFIG. 1, the refrigerating device30is configured to be movable up and down by the second elevating device78, and the mounting table20is configured to be movable up and down by the first elevating device77.

Before a film forming process, for example, the contact21aand the contact21bcan be brought into direct contact with each other by the upward movement of the refrigerating device30due to the second elevating device78as illustrated at the time of contact inFIG. 2A. Before the film forming process, the contact21aand the contact21bmay be brought into direct contact with each other by the downward movement of the mounting table20due to the first elevating device77as illustrated at the time of contact inFIG. 2A.

Meanwhile, at the time of the film forming process, a distance t1between the target T and the substrate W is adjusted by, for example, the upward movement of the mounting table20inside the vacuum processing container10due to the first elevating device77. The adjustment of the distance t1is appropriately changed according to the type of target T to be applied. Further, in order to form a film while the mounting table20is rotated during the film forming process, the contact21aand the contact21bare separated from each other as illustrated inFIG. 2B. As a result, a film can be formed on the substrate W, while the mounting table20is rotated by the rotating device40. When it is not necessary to adjust the distance t1, instead of moving the first elevating device77up, the second elevating device78may be moved down to separate the contact21aand the contact21bfrom each other. The contact21aand the contact21bmay be separated by synchronous control between the first elevating device77and the second elevating device78. Hereinafter, an example in which the refrigerating device30is moved up and down by the second elevating device78will be described.

In the case of an indirect method using a refrigerant such as a cooling gas, a partial contact cooling method using a powdery or paste-like heat conductive material, or an existing cooling method using both of them, a cooling operation may take some time due to low thermal conductivity. In this case, it becomes difficult to suppress the temperature rise of the mounting table20at the time of repeated heat input during the film forming process, to quickly return to a target cooling temperature at that time, and to control the temperature of the substrate W.

On the other hand, in the substrate processing apparatus100according to the present embodiment, the cold link35of the refrigerating device30and the mounting table20are physically brought into contact with each other via the contacts21aand21bexcept during the film forming process. As a result, the thermal conductivity from the refrigerating device30to the mounting table20is increased by direct contact of the contacts21aand21b, the cooling time of the substrate W can be shortened, and throughput can be enhanced.

The mounting table structure according to the present embodiment will be further described with reference toFIGS. 3A to 3C.FIGS. 3A to 3Care diagrams illustrating the periphery of the contact of the mounting table structure according to the embodiment.FIG. 3Billustrates a surface of the contact21aseen in a IIIB-IIIB direction ofFIG. 3A, andFIG. 3Cillustrates an arrangement of the spring26and the like under the contact21aseen in a IIIC-IIIC direction.

InFIGS. 2A and 2B, a configuration in which the plurality of contacts21aand the contacts21bare in direct contact with each other has been described. At this time, since the mounting part25and the contact21bare formed of copper (Cu) having high thermal conductivity, the contact21band the mounting part25are contact portions between metal workpieces. Therefore, as illustrated inFIG. 2B, an indium sheet23, which is soft and has good thermal conductivity, is sandwiched between the contact21band the mounting part25to avoid contact between the metal workpieces and to prevent metal contamination. A metal sheet other than the indium sheet23may be used.

However, the mounting table20is not limited to a stacked structure of the mounting part25and the contact21b, and as illustrated inFIG. 3A, the mounting part25and the contact21bmay be integrated into one plate. In this case, the plurality of contacts21aand the mounting part25(a convex portion25a) are in direct contact with each other.

In the present embodiment, a contact surface of the mounting part25that comes into contact with the plurality of contacts21ais circular and flat. Meanwhile, as illustrated inFIG. 3B, contact surfaces of the plurality of contacts21athat come into contact with the mounting part25have a shape in which a circle having the same diameter as the contact surface of the mounting part25is divided into four on the inner peripheral side and eight on the outer peripheral side. As described above, it is preferable that the contact21ais divided into a plurality of blocks, and the contact surface of the contact21ais divided into a plurality of blocks. In the example ofFIG. 3B, the contact21ais divided into 12 blocks and has 12 contact surfaces. More specifically, four contacts21ahaving contact surfaces21a2having the same contact area are provided on the inner peripheral side, and eight contacts21ahaving contact surfaces21a1having the same contact area are provided on the outer peripheral side. However, a shape of the contact surface of the contact21ais not limited thereto. The shape of the contact surface of the contact21amay be a circular shape, a quadrangular shape, or any other shape. The plurality of divided contact surfaces21a1and21a2of the contact21aare flat surfaces.

When the contact21ais not divided, the contact surface of the contact21abecomes one surface, and thus the contact with the mounting part25may be partially performed. On the other hand, since the contact surface is divided by dividing into the plurality of contacts21a, the contact surface of the mounting part25easily comes into surface contact with the contact surfaces21a1and21a2of the plurality of contacts21a. As a result, a contact area between the plurality of contacts21aand the mounting part25is increased as compared with a case in which the contact surface of the contacts21ais not divided, and contact efficiency can be enhanced.

As an example illustrated inFIG. 3C, one spring26is mounted on each of the contacts21adivided into 12 blocks. Since the spring26is provided for each of the12contacts21a, a mechanism in which, when the plurality of contacts21aand the mounting part25come into contact with each other, a force applied to each of the contacts21aand the mounting part25can be absorbed by the spring26is formed. In other words, it is possible to avoid damage to the plurality of contacts21aand the mounting part25by absorbing the force applied at the time of contact by the spring26.

When the contacts21aand the mounting part25are brought into contact with each other, the contacts21aand the mounting part25may not correctly come into contact with each other. Therefore, it is possible to make the contact by dividing the contact21ainto contact with the mounting part25more efficiently than to bring the contact21ainto contact with the mounting part25with a single plate, and the contact area increases. Further, when the plurality of springs26are provided, the contact between the contacts21aand the mounting part25can be smoothly obtained by an elastic force.

The spring26is preferably disposed at the center of each of the contacts21a, but the present disclosure is not limited thereto. Further, the spring26is an example of an elastic body, and the elastic body may be a compression coil, a leaf spring, or the like. The plurality of contacts21aare respectively connected to the plurality of springs26, and are mounted on the refrigerating device30or the mounting table20via the plurality of springs26. In the example ofFIGS. 3A to 3C, 12each of the contacts21ais connected to one of 12 springs26and the contacts21aare mounted on the upper surface of the cold link35of the refrigerating device30via the12springs26. However, the contact21amay be a single plate. When the contact21ais a single plate, the plurality of springs26may be mounted between the contact21aand the upper surface of the cold link35.

In the present embodiment, the springs26such as compression coils having the same diameter are disposed on the plurality of contacts21a, and the same number of springs26are disposed. However, for example, the springs26having different diameters may be disposed in the plurality of contacts21a. Thus, a degree of pressing of the contact surfaces21a1and21a2of the contacts21aon the mounting part25can be changed. Further, the number of springs26disposed in each of the plurality of contacts21amay be changed. As a result, the degree of pressing of the contact surfaces21a1and21a2of the contacts21aon the mounting part25can be changed.

Further, as illustrated inFIG. 3C, a copper plate27may be provided near the spring26mounted on each of the contacts21a. In the example ofFIG. 3C, two copper plates27are provided near the spring26of each of the contacts21a. The copper plate27is formed of a material such as a metal having high thermal conductivity such as copper in order to enhance heat transfer from the refrigerating device30to the plurality of contacts21a.

The number of copper plates27provided on each of the contacts21ais not limited to two and may be one or three or more. The copper plate27is disposed outside the spring26, but is not limited thereto, and can be provided at a position at which the copper plate27does not interfere with an expansion and contraction operation of the spring26. For example, the copper plate27may be provided on the upper surface or the side surface of each of the contacts21aas illustrated inFIG. 3C. The number of copper plates27disposed in each of the plurality of contacts21amay be changed.

When the substrate W on the mounting part25that is in direct contact with the plurality of contacts21afrom the refrigerating device30via the spring26is cooled, the cooling capacity from the refrigerating device30to the plurality of contacts21amay be deteriorated by the spring26. Therefore, a plurality of copper plates27as heat transfer members are provided on the plurality of contacts21a. As a result, the thermal conductivity from the refrigerating device30to the plurality of contacts21acan be increased, and the cooling efficiency of the mounting table20and the substrate W can be enhanced.

The plurality of copper plates27are an example of a plurality of heat transfer members connected to the plurality of contacts21a. The heat transfer member is not limited to the copper plate27and may be a conductive wire. The copper plate27has a structure that is thin to some extent and has high thermal conductivity to improve heat exchangeability without hindering an elastic force of the spring26. In other words, it is preferable that an example of the heat transfer member having the plurality of copper plates27has high heat transfer efficiency, does not have a function of a spring, and does not interfere with a function of the spring26. However, when the spring26itself is made of a material having high thermal conductivity, the copper plate27does not need to be provided.

As described above, the plurality of contacts21aaccording to the present embodiment are mounted on the refrigerating device30via the plurality of springs26and the plurality of copper plates27. Further, it is possible to make direct contact between the plurality of contacts21aand the mounting table20by moving the refrigerating device30up and down by the elevating drive part. As a result, it is possible to provide a substrate processing apparatus100that enhances heat transfer efficiency, improves the cooling efficiency of the substrate W, suppresses damage to the contact surface of the contact21a, and shortens the cooling time of the substrate W.

The contact provided between the cold link35and the mounting table20may be disposed only on the side of the cold link35, may be disposed only on the side of the mounting table20, or may be disposed on two sides of the cold link35and the mounting table20.

In the substrate processing apparatus100, at the time of the film forming process, an operation in which the contact is separated from the cold link35or the mounting table20, and before and after the film forming process, the contact is brought into contact with the cold link35or the mounting table20is repeatedly performed for each of the film forming processes of the substrate W. Therefore, as illustrated inFIGS. 2 and 3A to 3C, preferably, the surfaces of the contact21aand/or the contact21bare surface-treated with hard silver platings29and24so that the surfaces of the contacts21aand21bhave both durability against contact and separation, and thermal conductivity. The hard silver platings29and24suppress wear of the contact surfaces of the contacts21aand21bduring the contact and separation, and both the durability and the thermal conductivity of the contacts21aand21bcan be achieved at the same time. Not only the contact surfaces of the contacts21aand21b, but also the other surfaces of the contacts and the lower surface (the contact surface) of the mounting part25may be surface-treated with the hard silver platings29and24.

The contact surfaces of the contacts21aand21bare flat. The contact surfaces of the contacts21aand21bare processed so that flatness thereof is within 0.01 mm and plane roughness Ra is within 0.4. As a result, the contact area between the contact21aand the contact21b, or between the contact21aand the mounting part25can be made larger, the efficiency of heat conduction can be enhanced, and cooling efficiency can be further enhanced.

The spring26and the copper plate27connected to the contact21amay be provided on the side of the mounting table20, for example, as illustrated inFIG. 4. In the example ofFIG. 4, the spring26and the copper plate27are connected to the contact21bunder the mounting part25, and the plurality of contacts21aare disposed to be suspended in a downward direction of the spring26and the copper plate27. In this example, the plurality of contacts21aare provided on the side of the mounting table20and come into contact with the upper surface of the cold link35of the refrigerating device30.

As a contact method of the contact, a metal sealing material such as a metal O-ring or Acti-seal having thermal conductivity and springiness may be used instead of the block-shaped contacts21aand21b. However, since the block-shaped contacts21aand21bcan have a large contact area and have high cooling efficiency, the block-shaped contacts are preferable in consideration of heat exchangeability. The metal sealing material such as a metal O-ring or Acti-seal may be mounted on the contact surface of each of the block-shaped contacts21aand21b.

A driving method of the refrigerating device30, that is, a driving method of the second elevating device78may be an air cylinder or a motor. However, the air cylinder is preferable in that the refrigerating device30can be moved up and down only by controlling the on and off of air supply, and control is easy. Regarding the up and down movement of the refrigerating device30, a stroke of the refrigerating device30may be controlled by providing a stopper, which detects the moment when the contact21acomes into contact with the mounting part25or the contact21band stops the supply of air, to control the supply of the air cylinder.

When the refrigerating device30is driven by a motor, a ball screw or the like is required, and a required space is larger than that in driving by the air cylinder. Further, since the motor needs to be provided coaxially with the refrigerating device30, a size of a device increases. In this way, it is possible to save space by adopting a method of driving the refrigerating device30by the air cylinder. However, the refrigerating device30may be driven by a motor.

As illustrated inFIGS. 2 to 4, a radiation plate28may be provided around the refrigerating device30and the contacts21aand21b.

As described above, according to the mounting table structure and the substrate processing apparatus100having the mounting table structure of the present embodiment, a contact structure with a contact connected to the refrigerating device30can improve the thermal conductivity from the refrigerating device30to the mounting table20. As a result, the cooling efficiency of the substrate can be enhanced, and the time required for cooling the substrate W and returning to room temperature can be shortened.

[Operation of Substrate Processing Apparatus and Contact and Separation of Contact]

Next, an operation of the substrate processing apparatus100and contact and separation states of the contacts21aand21bwill be described with reference toFIG. 5.FIG. 5is a diagram illustrating an example of the operation of the substrate processing apparatus100and the state of the contacts according to the embodiment.

In the substrate processing apparatus100, the refrigerating device30is moved up and down by moving the second elevating device78up and down by an air cylinder, and the refrigerating device30and the mounting table20are brought into contact with or separated from each other via the contacts21aand21b. As a result, in the substrate processing apparatus100, contact (direct) cooling by the contacts21aand21bcan be performed. Hereinafter, the contact and separation states of the contacts21aand21bwhen the substrate W is processed by the substrate processing apparatus100will be sequentially described.

First, as illustrated in (1) ofFIG. 5, when the substrate W is loaded, the refrigerating device30is lifted by moving the second elevating device78up, and the contacts21aand21bare brought into contact with each other (the state ofFIG. 2A). At this time, the rotation operation by the rotating device40is stopped, and the mounting table20is not rotating.

Next, as illustrated in (2) ofFIG. 5, a DC voltage is applied to the chuck electrode32, and the substrate W is cooled in a state in which the substrate W is suctioned by the electrostatic chuck. Following the (1) ofFIG. 5, the contacts21aand21bare in a contact state (the state ofFIG. 2A). At this time, the rotation operation by the rotating device40is stopped.

Next, as illustrated in (3) ofFIG. 5, immediately before a process (for example, the film forming process) is performed, the refrigerating device30is moved down by moving the second elevating device78down, and the contacts21aand21bare separated from each other during the process (the state ofFIG. 2B). At this time, the contact between the contacts21aand21billustrated by A inFIG. 2Abecomes a non-contact (separated) state illustrated by A inFIG. 2B, and the spring26illustrated by B inFIG. 2Aextends as illustrated by B inFIG. 2B. Further, at this time, the rotation operation is performed by the rotating device40, and the film forming process is performed on the substrate W in a state in which the mounting table20is rotated.

In the present embodiment, when the cooling structure (including the contact21aon the cooling side) is formed in a block structure having a large volume, it is possible to enhance thermal conductivity at the time of contact. Further, for example, when the mounting table20(the contact21bon the cooled side) is formed in a block structure having a large volume, cold storage efficiency at the time of separation can be enhanced.

Further, it is possible to reduce the wear at the time of contact and to enhance reproducibility of a contact pressure by providing the spring26on the contact. The spring26may be provided on the side of the mounting table, and pressing pressure at the time of contact can be adjusted by the plurality of springs26.

Next, the application of the DC voltage to the chuck electrode32is stopped, and the substrate W is unloaded as illustrated in (4) ofFIG. 5in a state in which the substrate W is not suctioned on the mounting table20due to an electrostatic elimination process. At this time, the rotation operation by the rotating device40is not performed, and the mounting table20is not rotating. The refrigerating device30is moved up by moving the elevating device78up and down, and the contacts21aand21bare in contact with each other (the state illustrated inFIG. 2A).

Next, as illustrated in (5) ofFIG. 5, when the substrate W is idling after it is unloaded (waiting for the substrate W to be loaded), the contacts21aand21bare kept in the contact state (the state ofFIG. 2A). At this time, the rotation operation by the rotating device40is stopped. When the next substrate W is loaded, the process returns to (1) ofFIG. 5, and the processes of (1) to (5) ofFIG. 5are performed.

[Method of Controlling Substrate Processing Apparatus]

Next, a method of controlling the substrate processing apparatus100according to the embodiment will be described with reference toFIG. 6.FIG. 6is a flowchart illustrating an example of the method of controlling the substrate processing apparatus100according to the embodiment. The process ofFIG. 6is controlled by the controller80. A solid line arrow indicates a processing direction when the temperature of the mounting part25on which the substrate W is mounted is normal, and a broken line arrow indicates a processing direction when the temperature of the mounting part25is abnormal.

When this processing is started, before the substrate W mounted on the mounting part25of the mounting table20is processed, the controller80causes the refrigerating device30to be moved up and down by the second elevating device78and controls the contacts to be brought into contact with the refrigerating device30or the mounting part25(Step1).

Due to the control of Step S1, for example, in the example ofFIG. 2A, the contact21acomes into contact with the mounting part25via the contact21b. Further, for example, in the example ofFIG. 4, the contact21acomes into contact with the cold link35. As a result, the controller80directly cools the mounting part25from the refrigerating device30(Step S2). When the temperature of the mounting part25reaches a saturated state and the mounting part25is stabilized at a predetermined temperature (Step S3), the controller80loads the substrate W (Step S4). On the other hand, when the temperature of the mounting part25does not reach the saturation state in Step S3and the temperature of the mounting part25is abnormal, the controller80does not load the substrate W and returns to Step S2. In Step S2, the mounting part25is cooled again by the refrigerating device30, and the processes of Steps S2and S3are repeated until the temperature of the mounting part25reaches the saturated state.

After the substrate W is loaded in Step S4, the controller80applies a DC voltage to the chuck electrode32and controls the substrate W to be contact-cooled in a state in which the substrate W is suctioned by the electrostatic chuck (Step S5). Further, the controller80controls so that the first cooling gas (for example, He gas) is supplied from the refrigerant supply flow path51to a space in which the spring26is disposed, and the second cooling gas (for example, He gas) is supplied from the second cooling gas supply pipe34to a space between the lower surface of the substrate W and the upper surface of the mounting part25.

Next, the controller80controls the contact21ato be separated from the mounting part25in order to perform the film forming process (Step S6). As a result, as illustrated inFIG. 2B, the contact21ais separated from the mounting part25via the contact21b. However, when the mounting table20is not rotated during the film forming process, the process may proceed to Step S7without performing the process of Step S6.

Due to Step S6, the contact21ais separated from the mounting part25, and the mounting part25can be rotated. The controller80controls the substrate W to be subjected to a desired film forming process while the mounting part25is rotated by the rotating device40(Step S7). However, when the film forming process is performed without rotating the mounting part25, the controller80performs Step S6or does not perform Step S6and then performs the film forming process on the substrate W without rotating the substrate W. The controller80stops the rotation of the mounting table20by the rotating device40after the film forming process on the substrate W is performed.

Next, the controller80causes the refrigerating device30to be moved up by the second elevating device78, controls the contact21ato be brought into contact with the mounting part25via the contact21b, and cools the mounting part25by the refrigerating device30(Step S8). Then, the controller80unloads the substrate W (Step S9) and finishes this processing.

In Steps S4to S8, when it is determined that the temperature of the mounting part25is abnormal because it exceeds a predetermined threshold value, the controller80stops the process (Step S10) and returns to the process of bringing the contacts21aand21bof Step S2into contact with each other and cooling the mounting part25. In this case, the controller80performs the processing after Step S2again.

Further, in the method of controlling the substrate processing apparatus100ofFIG. 6, the refrigerating device30is moved up and down by the second elevating device78, and the contacts are brought into contact with or separated from the refrigerating device30or the mounting table20. However, the present disclosure is not limited thereto, and for example, the refrigerating device30may be moved up and down by the first elevating device77, and the contacts may be brought into contact with or separated from the refrigerating device30or the mounting table20.

It should be considered that the mounting table structure, the substrate processing apparatus, and the method of controlling the substrate processing apparatus according to the embodiments disclosed herein are exemplary in all respects and should be considered as not being restrictive. The embodiments may be modified and improved in various forms without departing from the scope of the appended claims and their gist. The matters described in the plurality of embodiments may have other configurations within a non-contradictory range and may be combined within a non-contradictory range.