Plasma processing system and method for estimating height of annular member

Abstract

A plasma processing system comprising: a plasma processing device; a depressurizing transportation device that is connected to the plasma processing device and has a transportation robot for transporting a substrate; and a control device. The plasma processing device has: a processing container configured to be depressurizable; a substrate support platform that is provided inside the processing container, has a substrate placement surface and an electrostatic chuck for electrostatically adhering the substrate to the substrate placement surface, and has installed thereon an annular member so as to surround the substrate placement surface; a raising-and-lowering mechanism that raises and lowers the substrate in relation to the substrate placement surface; and a gas supply unit that supplies a gas inside the processing container. The transportation robot has a holding unit configured to be capable of holding a to-be-transported substrate, and a distance sensor that is provided to the holding unit and is for measuring the distance from the holding unit. The control unit executes (A) a step for transporting, into the processing container by using the transportation robot, a jig substrate having a reference surface serving as a height reference for the annular member, and placing the jig substrate onto the substrate support platform by using the raising-and-lowering mechanism, (B) a step for applying a voltage to the electrostatic chuck in a state in which the gas is supplied into the processing container, and adhering the jig substrate in a plasmaless manner to the substrate placement surface, (C) a step for positioning the holding unit of the transportation robot above the substrate support platform, and measuring, by using the distance sensor, the distance to the reference surface of the jig substrate placed on the substrate placement surface and the distance to the annular member installed on the substrate support platform, and (D) a step for estimating the height of the annular member on the basis of the measurement result of the distance to the reference surface and the distance to the annular member.

Description

[Technical Field]

[0001] The present disclosure relates to a plasma processing system and a method for estimating the height of an annular member. [Background technology]

[0002] Patent Document 1 discloses a processing system for processing substrates in a reduced-pressure environment. This processing system includes a processing chamber for performing a desired process on a substrate, a transfer chamber equipped with a transport mechanism for loading and unloading the substrate into and from the processing chamber, and a controller for controlling the processing process in the processing chamber. The transport mechanism includes a fork mechanism for holding and transporting the substrate on its upper surface and a measurement mechanism attached to the fork mechanism for measuring the internal state of the processing chamber. The controller controls the processing process in the processing chamber based on the internal state of the processing chamber acquired by the measurement mechanism. The processing chamber may also include an electrostatic chuck for attracting and holding the substrate on its upper surface, an edge ring arranged to surround the substrate-holding surface of the electrostatic chuck in a plan view, and a link power supply for applying a DC voltage to the edge ring. The measurement mechanism includes a distance sensor for measuring the height position of the upper surface of the edge ring. The controller controls the amount of DC voltage applied from the ring power supply based on the height position of the upper surface of the edge ring acquired by the measurement mechanism. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-69274 Summary of the Invention [Problem to be solved by the invention]

[0004] The technique according to the present disclosure accurately estimates the height of an annular member attached to a substrate support pedestal. [Means for solving the problem]

[0005] One aspect of the present disclosure is a plasma processing system including: a plasma processing apparatus; a reduced-pressure transfer apparatus connected to the plasma processing apparatus and having a transfer robot for transferring a substrate; and a control device; wherein the plasma processing apparatus includes a processing vessel configured to be depressurized; a substrate support table provided within the processing vessel, the substrate support table having a substrate mounting surface and an electrostatic chuck that electrostatically attracts a substrate to the substrate mounting surface; a substrate support table having an annular member attached to surround the substrate mounting surface; a lifting mechanism that raises and lowers the substrate relative to the substrate mounting surface; and a gas supply unit that supplies gas into the processing vessel; the transfer robot includes a holder configured to be able to hold the substrate to be transferred; and a distance sensor provided on the holder that measures a distance from the holder; and the control device The method includes the steps of: (A) using the transport robot to transport a jig substrate having a reference surface that serves as a reference for the height of the annular member into the processing vessel and placing it on the substrate support table using the lifting mechanism; (B) applying a voltage to the electrostatic chuck while supplying the gas into the processing vessel to adsorb the jig substrate to the substrate support surface in a plasmaless manner; (C) positioning the holding part of the transport robot above the substrate support table and using the distance sensor to measure the distance to the reference surface of the jig substrate placed on the substrate support surface and the distance to the annular member attached to the substrate support table; and (D) estimating the height of the annular member based on the measurement results of the distance to the reference surface and the distance to the annular member. [Effects of the Invention]

[0006] According to the present disclosure, the height of an annular member attached to a substrate support table can be accurately estimated. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a plan view showing an outline of the configuration of a plasma processing system according to an embodiment of the present invention; [Figure 2] FIG. 2 is a diagram showing an outline of the configuration of a transport robot provided in a transfer module. [Figure 3]FIG. 2 is a bottom view showing the outline of the configuration of the fork. [Figure 4] FIG. 2 is a longitudinal cross-sectional view showing an outline of the configuration of a processing module. [Figure 5] FIG. 5 is a partially enlarged view of FIG. [Figure 6] FIG. 2 is a partially enlarged cross-sectional view of the electrostatic chuck. [Figure 7] FIG. 10 is a plan view of an example of a jig wafer as a jig substrate used for estimating the height of an edge ring. [Figure 8] 10 is a flowchart illustrating an example of a method for estimating the height of an edge ring. [Figure 9] FIG. 10 illustrates the position of the fork and distance sensor relative to the wafer support pedestal when estimating the edge ring height. [Figure 10] FIG. 10 is a diagram for explaining another example of the processes of step S3 and step S4. [Figure 11] FIG. 10 is a plan view schematically showing another example of a jig wafer. [Figure 12] FIG. 10 is a cross-sectional view schematically showing another example of a jig wafer. [Figure 13] 10A and 10B are diagrams showing the results of a test conducted to confirm the repeatability of the edge ring height estimation results using the technology disclosed herein. [Figure 14] FIG. 10 is a top view illustrating another example of the annular member. DETAILED DESCRIPTION OF THE INVENTION

[0008] In the manufacturing process of semiconductor devices, etc., substrate processing, such as etching using plasma, i.e., plasma processing, is performed on substrates such as semiconductor wafers (hereinafter referred to as "wafers"). The plasma processing is performed with the substrate placed on a substrate support table inside a reduced-pressure processing chamber.

[0009] On the substrate support table, an edge ring or a cover ring, which is an annular member in a planar view, is placed so as to surround the substrate on the substrate support table. The edge ring (also called a focus ring) is an annular member disposed adjacent to the substrate on the substrate support table, and the cover ring is an annular member disposed so as to cover the outer surface of the edge ring. These edge rings and cover rings are etched and worn away by exposure to plasma. Wear of the edge ring or cover ring may result in inappropriate plasma processing results. Specifically, for example, wear of the edge ring may change the shape of the plasma sheath, resulting in inappropriate plasma processing results.

[0010] Therefore, a sensor has been conventionally used to estimate the height of an annular member such as an edge ring placed on a substrate support table (in other words, the degree of wear of the annular member). For example, the wear amount of the edge ring may be estimated based on a measured distance from a sensor provided on a transfer arm of a substrate transfer device that transfers substrates to and from a processing chamber to the surface of the edge ring and a measured distance from the sensor to the surface of the substrate support table.

[0011] However, when the height of an annular member such as an edge ring is estimated based on the distance from the sensor to the surface of the substrate support table (specifically, the substrate support surface on which the substrate is placed), the estimation result may not be accurate. For example, the surface of the substrate support table may be intentionally uneven. In this case, the estimation result of the height of the annular member may differ depending on which part of the uneven surface that forms the unevenness on the surface of the substrate support table the sensor measures the distance to. However, when the unevenness is small, it is difficult for the sensor to select which part of the uneven surface on the surface of the substrate support table the sensor measures the distance to.

[0012] One possible approach is to place a dummy substrate, such as a silicon substrate, on the substrate support table and estimate the height of an annular member such as an edge ring based on the distance from the dummy substrate to the sensor. However, simply placing the dummy substrate on the substrate support table will result in different amounts of charge on the substrate support surface depending on the timing of measuring the distance, which will in turn result in different adhesion forces of the dummy substrate to the substrate support table. Therefore, the distance from the dummy substrate to the sensor cannot be accurately measured, and the height of an annular member such as an edge ring cannot be accurately estimated.

[0013] Another method that has been considered is to estimate the amount of wear based on the measurement results of the edge ring height before plasma processing and the measurement results of the current edge ring height. However, with this estimation method, if the tip of the transfer arm equipped with the sensor sags under its own weight as the substrate is repeatedly loaded and unloaded, the measurement results of the current edge ring height may become inaccurate, making it impossible to accurately estimate the amount of wear.

[0014] Therefore, the technique according to the present disclosure accurately estimates the height of the annular member attached to the substrate support table.

[0015] Hereinafter, a plasma processing system and a method for estimating the height of an annular member according to this embodiment will be described with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0016] <Plasma processing system> Fig. 1 is a plan view showing the outline of the configuration of a plasma processing system according to this embodiment. Fig. 2 is a diagram showing the outline of the configuration of a transfer robot provided in a transfer module (described later). Fig. 3 is a bottom view showing the outline of the configuration of a fork (described later). In the plasma processing system 1 of FIG. 1, a wafer W as a substrate is processed, and more specifically, a substrate processing such as an etching process using plasma, that is, a plasma processing is performed on the wafer W.

[0017] The plasma processing system 1 has an atmospheric section 10 that operates under atmospheric pressure and a decompression section 11 that operates under reduced pressure, and the atmospheric section 10 and the decompression section 11 are connected together via load lock modules 20 and 21. The atmospheric section 10 includes an atmospheric module that performs a desired process on a wafer W under atmospheric pressure. The decompression section 11 includes a decompression module that performs a desired process on a wafer W under a reduced pressure (vacuum) atmosphere.

[0018] The load lock modules 20 and 21 are provided to connect the loader module 30 included in the atmospheric section 10 and the transfer module 50 included in the reduced pressure section 11 via a gate valve (not shown). The load lock modules 20 and 21 are configured to temporarily hold the wafer W. The load lock modules 20 and 21 are load lock devices configured so that the interior thereof can be switched between an atmospheric pressure atmosphere and a reduced pressure atmosphere.

[0019] The atmospheric section 10 has a loader module 30 as an atmospheric pressure transfer device that operates under atmospheric pressure and has a transfer mechanism 40 described below, and a load port 32 on which a FOUP 31 is placed. The FOUP 31 is a storage container that can store multiple wafers W. Note that the loader module 30 may be connected to an orienter module (not shown) that adjusts the horizontal orientation of the wafer W, a buffer module (not shown) that temporarily stores multiple wafers W, and the like.

[0020] The loader module 30 has a rectangular housing, the interior of which is maintained at atmospheric pressure. A plurality of, for example, five load ports 32 are arranged side by side on one side that constitutes the long side of the housing of the loader module 30. Load lock modules 20 and 21 are arranged side by side on the other side that constitutes the long side of the housing of the loader module 30. In one embodiment, a storage module 33 serving as a substrate storage unit for storing jig wafers Wj serving as jig substrates is connected to one side surface constituting a short side of the housing of the loader module 30. The storage module 33 may also serve as the buffer module described above.

[0021] A transfer mechanism 40 configured to hold and transfer a wafer W is provided inside the housing of the loader module 30. The transfer mechanism 40 has a transfer arm 41 that supports the wafer W during transfer, a rotary table 42 that rotatably supports the transfer arm 41, and a base 43 on which the rotary table 42 is mounted. Also, a guide rail 44 extending in the longitudinal direction of the loader module 30 is provided inside the loader module 30. The base 43 is provided on the guide rail 44, and the transfer mechanism 40 is configured to be movable along the guide rail 44.

[0022] The decompression unit 11 includes a transfer module 50 as a decompression transfer device and a processing module 60 as a plasma processing device. The decompression unit 11 may include a storage module 61 as a material storage unit. The interiors of the transfer module 50 and the processing module 60 (specifically, the interiors of the decompression transfer chamber 51 and chamber 100 described below) are each maintained in a decompression atmosphere, and the interior of the storage module 61 is also maintained in a decompression atmosphere. For one transfer module 50, multiple processing modules 60, for example, six, are provided, and multiple storage modules 61, for example, two, are also provided. Note that the number and arrangement of the processing modules 60 are not limited to this embodiment and can be set arbitrarily, as long as at least one processing module equipped with a wafer support table described below is provided. Furthermore, the number and arrangement of the storage modules 61 are not limited to this embodiment and can be set arbitrarily, for example, at least one is provided.

[0023] The transfer module 50 is configured to transfer the wafer W therein. The transfer module 50 may also be configured to transfer the edge ring E (described later) therein. The transfer module 50 includes a decompression transfer chamber 51 having a housing that is polygonal in plan view (rectangular in plan view in the illustrated example), and the decompression transfer chamber 51 is connected to the load lock modules 20 and 21.

[0024] The transfer module 50 transfers the wafer W loaded into the load lock module 20 to one of the processing modules 60, and also unloads the wafer W that has been subjected to the desired plasma processing in the processing module 60 to the load lock module 21. Furthermore, the transfer module 50 may transport the edge ring E in the storage module 61 to one of the processing modules 60 and may also unload the edge ring E in the processing module 60 to the storage module 61 .

[0025] The processing module 60 performs a desired plasma processing, such as an etching process, on the wafer W transferred from the transfer module 50. The processing module 60 is connected to the transfer module 50 via a gate valve 62. The specific configuration of the processing module 60 will be described later.

[0026] The storage module 61 stores the edge ring E. The storage module 61 is connected to the transfer module 50 via a gate valve 63.

[0027] A transfer robot 70 is provided inside the reduced pressure transfer chamber 51 of the transfer module 50. The transfer robot 70 is configured to be able to hold and transfer a wafer W. The transfer robot 70 is also configured to be able to hold and transfer an edge ring E.

[0028] The transfer robot 70 has a transfer arm 71 that is configured to be able to rotate, extend, and move up and down freely while holding a wafer W. The tip of the transfer arm 71 is branched into forks 72, 72 that serve as two holders. The forks 72, 72 are configured to be able to hold the wafer W and edge ring E to be transferred, respectively.

[0029] 2, a distance sensor 73 is provided on at least one of the forks 72, 72. The distance sensor 73 measures the distance from the fork 72 (specifically, the distance sensor 73) to a target point.

[0030] 3, the fork 72 has a bifurcated shape with a width smaller than the diameter of the wafer W. The distance sensors 73 are, for example, a distance sensor 73a provided at one tip of the bifurcated portion of the fork 72, and a distance sensor 73b provided at the other tip.

[0031] Furthermore, a method that enables non-contact measurement in a reduced pressure atmosphere, such as a method based on light, is used for measuring distance using distance sensor 73. In this case, for example, distance sensor 73 irradiates a target with distance measurement light and receives the reflected light, and a unit controller (not shown) connected to distance sensor 73 via optical fiber 74 measures the distance from fork 72 (specifically distance sensor 73) to the target point based on the light reception result by distance sensor 73.

[0032] A more specific example of a distance measurement method using the distance sensor 73 is a white light confocal method. When the white light confocal method is adopted, for example, white light supplied from a light source (not shown) such as an LED included in the unit controller is irradiated from the distance sensor 73 onto the object so that the white light is focused at different heights for each wavelength contained in the white light. Then, only the light of the wavelength that is focused on the object is input to the unit controller via the distance sensor 73 as reflected light. The unit controller calculates the distance from the fork 72 (specifically, the distance sensor 73) to the object point based on the wavelength of the input light. The distance sensor 73 is disposed so that the optical axis of the white light is approximately parallel to the vertical direction. The white light confocal method is merely one example, and any method capable of measuring distance with the desired accuracy (for example, a vertical resolution of 15 μm or less and a horizontal resolution of about 0.1 mm) may be used.

[0033] As described above, the distance sensor 73 and the unit controller are connected via an optical fiber 74, and the distance measurement light (white light) and reflected light are transmitted via the optical fiber 74. An optical switch (not shown) is interposed in the optical fiber 74.

[0034] The unit controller and the optical switch are provided, for example, in a space under atmospheric pressure outside the reduced pressure transfer chamber 51. The unit controller not only calculates or measures the distance from the fork 72 (specifically, the distance sensor 73) to the target point based on the light reception result by the distance sensor 73 as described above, but also controls the measurement by the distance sensor 73 under the control of the control device 80 described below.

[0035] In the transfer module 50, the transfer arm 71 receives the wafer W held in the load lock module 20 and carries it into the processing module 60. In addition, the transfer arm 71 receives the wafer W that has been subjected to the desired processing in the processing module 60 and carries it out to the load lock module 21.

[0036] Furthermore, in the transfer module 50, the transport arm 71 may receive the edge ring E in the storage module 61 and carry it into the processing module 60. Furthermore, in the transfer module 50, the transport arm 71 may receive the edge ring E in the processing module 60 and carry it out to the storage module 61.

[0037] The plasma processing system 1 further includes a controller 80. In one embodiment, the controller 80 processes computer-executable instructions that cause the plasma processing system 1 to perform the various processes described herein. The controller 80 may be configured to control each of the other elements of the plasma processing system 1 so that the plasma processing system 1 performs the various processes described herein. In one embodiment, some or all of the controller 80 may be included in the other elements of the plasma processing system 1. The controller 80 may include, for example, a computer 90. The computer 90 may include, for example, a processing unit (CPU: Central Processing Unit) 91, a memory unit 92, and a communication interface 93. The processing unit 91 may be configured to perform various control operations and calculations based on programs stored in the memory unit 92. The memory unit 92 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 93 may communicate with the other elements of the plasma processing system 1 via a communication line such as a local area network (LAN).

[0038] <Wafer processing in plasma processing system 1> Next, an example of wafer processing using the plasma processing system 1 configured as above will be described.

[0039] First, the transfer mechanism 40 removes the wafer W from the desired FOUP 31 and loads it into the load lock module 20. Next, the inside of the load lock module 20 is sealed and depressurized. After that, the inside of the load lock module 20 and the inside of the transfer module 50 are connected to each other.

[0040] Next, the wafer W is held by the transfer robot 70 and transferred from the load lock module 20 to the transfer module 50 .

[0041] Next, the gate valve 62 corresponding to the desired processing module 60 is opened, and the transfer robot 70 loads the wafer W into the desired processing module 60. Thereafter, the gate valve 62 is closed, and the desired processing is performed on the wafer W in the processing module 60. The processing performed on the wafer W in this processing module 60 will be described later.

[0042] Next, the gate valve 62 is opened, and the transfer robot 70 unloads the wafer W from the processing module 60. Thereafter, the gate valve 62 is closed.

[0043] Next, the transfer robot 70 loads the wafer W into the load lock module 21. When the wafer W is loaded into the load lock module 21, the inside of the load lock module 21 is sealed and opened to the atmosphere. Thereafter, the inside of the load lock module 21 and the inside of the loader module 30 are connected to each other.

[0044] Next, the wafer W is held by the transfer mechanism 40, and is returned from the load lock module 21 to the desired FOUP 31 via the loader module 30 and accommodated therein. This completes the wafer processing using the plasma processing system 1.

[0045] <Processing Module 60> Next, the processing module 60 will be described with reference to Figs. 4 to 6. Fig. 4 is a vertical cross-sectional view showing the outline of the configuration of the processing module 60. Fig. 5 is a partially enlarged view of Fig. 4. Fig. 6 is a partially enlarged cross-sectional view of an electrostatic chuck, which will be described later.

[0046] 4, the processing module 60 includes a chamber 100 as a processing container, a gas supply mechanism 140, an RF (Radio Frequency) power supply unit 150, and an exhaust system 160. The processing module 60 also includes a voltage application unit 120 (see FIG. 5). The processing module 60 further includes a wafer support pedestal 101 as a substrate support pedestal, and an upper electrode 102.

[0047] The chamber 100 is configured so that its interior can be depressurized, and defines a processing space 100s in which plasma is generated. The chamber 100 also includes a wafer support pedestal 101 and other components. The chamber 100 may be made of, for example, aluminum. The chamber 100 is also connected to ground potential.

[0048] The wafer support pedestal 101 is disposed, for example, in a lower region within the chamber 100. The upper electrode 102 is disposed above the wafer support pedestal 101 and can function as part of the ceiling of the chamber 100.

[0049] The wafer support pedestal 101 is configured to support a wafer W. In one embodiment, the wafer support pedestal 101 includes a lower electrode 103, an electrostatic chuck 104, a support 105, an insulator 106, and a lifter 107. The wafer support pedestal 101 may also include a lifter 108. The wafer support pedestal 101 is configured to have an edge ring E attached thereto, and specifically, is configured to also support the edge ring E. The wafer support pedestal 101 may or may not include the edge ring E as a component thereof.

[0050] The lower electrode 103 is formed of a conductive material such as aluminum. The lower outer periphery of the lower electrode 103 and the upper inner periphery of the support 105 may be formed to overlap in a plan view. In one embodiment, a temperature control fluid flow path 109 is formed inside the lower electrode 103. A temperature control fluid is supplied to the flow path 109 from a chiller unit (not shown) provided outside the chamber 100. The temperature control fluid supplied to the flow path 109 returns to the chiller unit. By circulating, for example, low-temperature brine as a temperature control fluid through the flow path 109, it is possible to cool, for example, the wafer support table 101 (specifically, the electrostatic chuck 104), the wafer W, or the edge ring E to a predetermined temperature. By circulating, for example, high-temperature brine as a temperature control fluid through the flow path 109, it is possible to heat, for example, the wafer support table 101 (specifically, the electrostatic chuck 104), the wafer W, or the edge ring E to a predetermined temperature. When a temperature control mechanism is provided on the wafer support table 101, the form of the temperature control mechanism is not limited to the above-described flow path 109, and may be other forms such as a resistance heating heater. Also, the component on the wafer support table 101 on which the temperature control mechanism is provided is not limited to the lower electrode 103, and may be other components.

[0051] The electrostatic chuck 104 is a member configured to electrostatically attract at least the wafer W and is provided on the lower electrode 103. The electrostatic chuck 104 may also be configured to electrostatically attract the edge ring E. In one embodiment, the central portion of the electrostatic chuck 104 constitutes a substrate mounting portion. In another embodiment, the electrostatic chuck 104 has a central upper surface higher than a peripheral upper surface. In one embodiment, the wafer W is mounted on a central upper surface 104a of the electrostatic chuck 104, and the edge ring E is mounted on a peripheral upper surface 104b of the electrostatic chuck 104. That is, in one embodiment, the central upper surface 104a of the electrostatic chuck 104 serves as a wafer mounting surface on which the wafer W is mounted, and the peripheral upper surface 104b of the electrostatic chuck 104 serves as a ring mounting surface on which the edge ring E is mounted so as to surround the substrate mounting surface.

[0052] The edge ring E is a member arranged to surround the wafer mounting surface, i.e., a member arranged to surround the wafer W, specifically, a member arranged to surround the wafer W mounted on the electrostatic chuck 104. In one embodiment, the edge ring E is arranged to surround the central portion of the electrostatic chuck 104, the upper surface of which is higher than the peripheral portion. The edge ring E is formed in a circular ring shape in a plan view. The edge ring E is made of a material such as Si or SiO2.

[0053] An electrode 110 for electrostatically attracting a wafer W to an upper surface 104a of the central portion of the electrostatic chuck 104 is provided at the central portion. An electrode 111 for electrostatically attracting an edge ring E to an upper surface 104b of the peripheral portion of the electrostatic chuck 104 may also be provided at the peripheral portion of the electrostatic chuck 104. The electrode 111 is, for example, a bipolar electrode including a pair of electrodes 111a and 111b formed at different positions from each other. The electrostatic chuck 104 has a configuration in which electrodes 110 and 111 are sandwiched between insulating materials made of, for example, an insulating material.

[0054] As shown in FIG. 5, a voltage application unit 120 is connected to the electrode 110 so as to generate an electric force (specifically, for example, Coulomb force) for electrostatically attracting the wafer W.

[0055] The voltage application unit 120 includes a DC power supply 121a and a switch 122a. The DC power supply 121a is connected to the electrode 110 via the switch 122a, and applies a voltage to the electrode 110 for electrostatically attracting the wafer W. The DC power supply 121a can selectively apply a positive voltage or a negative voltage to the electrode 110.

[0056] The voltage application unit 120 may be connected to the electrode 111 so as to generate an electric force for electrostatically attracting the edge ring E. If the electrode 111 is a bipolar type, the voltage application unit 120 may be configured to selectively apply either voltages of opposite polarities or voltages of the same polarity to the pair of electrodes 111a, 111b.

[0057] The voltage application unit 120 includes, for example, two DC power supplies 121b and 121c and two switches 122b and 122c. The DC power supply 121b is connected to the electrode 111a via, for example, a switch 122b, and selectively applies a positive voltage or a negative voltage to the electrode 111a to electrostatically attract the edge ring E. The DC power supply 121c is connected to the electrode 111b via, for example, a switch 122c, and selectively applies a positive voltage or a negative voltage to the electrode 111b to electrostatically attract the edge ring E.

[0058] In this embodiment, the central portion of the electrostatic chuck 104 where the electrode 110 is provided and the peripheral portion where the electrode 111 is provided are integrated, but these central portion and peripheral portion may be separate. In addition, in this embodiment, the electrode 111 for attracting and holding the edge ring E is a bipolar type, but it may be a unipolar type.

[0059] 6, a plurality of protrusions 104c may be provided on the top surface 104a at the center of the electrostatic chuck 104. This can reduce the force of attraction of the wafer W to the electrostatic chuck 104 due to residual charges when the voltage application to the electrode 110 is stopped. The plurality of protrusions 104c are provided, for example, at equal intervals. The protrusions 104c are formed, for example, in a cylindrical shape with a diameter of 300 μm to 500 μm and a height of 5 μm to 30 μm.

[0060] As shown in FIG. 5, the central portion of the electrostatic chuck 104 is formed with a diameter smaller than that of the wafer W, for example, so that when the wafer W is placed on the upper surface 104a of the central portion of the electrostatic chuck 104, the peripheral portion of the wafer W protrudes beyond the central portion of the electrostatic chuck 104. The edge ring E has a step formed on its upper portion, and the upper surface of the outer periphery is higher than the upper surface of the inner periphery. The inner periphery of the edge ring E is formed to be recessed below the peripheral edge of the wafer W that protrudes from the center of the electrostatic chuck 104. In other words, the inner diameter of the edge ring E is formed to be smaller than the outer diameter of the wafer W.

[0061] The support 105 is a member formed of an insulating material such as quartz in a ring shape in a plan view, and is disposed so as to surround the lower electrode 103 and the electrostatic chuck 104.

[0062] The electrostatic chuck 104 may have gas discharge holes (not shown) formed in its central upper surface 104a for discharging a heat transfer gas into a gap between the back surface of the placed wafer W and the upper surface 104a. The heat transfer gas is supplied from a gas supply unit (not shown) through the gas discharge holes. The gas supply unit may include one or more gas sources and one or more pressure controllers. In one embodiment, the gas supply unit is configured to supply the heat transfer gas from the gas source to the gas supply holes via the pressure controller, for example.

[0063] Furthermore, gas discharge holes (not shown) may be formed in the upper surface 104b of the peripheral portion of the electrostatic chuck 104 to discharge a heat transfer gas into a gap between the upper surface 104b and the back surface of the mounted edge ring E. The heat transfer gas is supplied from a gas supply unit (not shown) through the gas discharge holes. The gas supply unit may include one or more gas sources and one or more pressure controllers. In one embodiment, the gas supply unit is configured to supply the heat transfer gas from the gas source to the gas supply holes via the pressure controller, for example.

[0064] 4 is a cylindrical member made of ceramic or the like, and supports the support 105. The insulator 106 is formed, for example, to have an outer diameter equal to the outer diameter of the support 105, and supports the periphery of the support 105.

[0065] The lifter 107 is a member that moves up and down relative to the upper surface 104a at the center of the electrostatic chuck 104, and is formed, for example, in a columnar shape using a ceramic material. When the lifter 107 is raised, its upper end protrudes from the upper surface 104a, and the lifter 107 can support the wafer W. Three or more lifters 107 are provided at intervals from one another and extend in the vertical direction.

[0066] The lifters 107 are raised and lowered by an actuator 112. The actuator 112 has, for example, a support member 113 that supports the plurality of lifters 107, and a drive unit 114 that generates a drive force for raising and lowering the support member 113, thereby raising and lowering the plurality of lifters 107. The drive unit 114 has, for example, a motor (not shown) as a drive source that generates the drive force.

[0067] The lifter 107 is inserted into an insertion hole 115 whose upper end opens in the upper surface 104a of the central portion of the electrostatic chuck 104. The insertion hole 115 is formed, for example, to extend downward from the upper surface 104a of the central portion of the electrostatic chuck 104 to reach the bottom surface of the lower electrode 103.

[0068] The above-described lifter 107 allows the wafer W to be transferred between the wafer support table 101 and the transfer arm 71 of the transfer robot 70. The lifter 107 and the actuator 112 constitute a lifting mechanism that lifts and lowers the wafer W relative to the wafer placement surface.

[0069] The lifter 108 is a lifting member that moves up and down relative to the upper surface 104b of the peripheral edge of the electrostatic chuck 104, and is formed into a columnar shape using, for example, a ceramic material. In one embodiment, the lifter 108 is configured so that its upper end can protrude from the upper surface 105a of the support 105 when raised. Three or more lifters 108 are provided along the circumferential direction of the electrostatic chuck 104 at intervals, and extend in the vertical direction.

[0070] The lifters 108 are raised and lowered by actuators 116. The actuators 116 are provided, for example, for each lifter 108, and include support members 117 that support the lifters 108 so that they can move horizontally. The support members 117 include, for example, thrust bearings to support the lifters 108 so that they can move horizontally. The actuators 116 also include a drive unit 118 that generates a drive force to raise and lower the support members 117 and raise and lower the lifters 108. The drive unit 118 includes, for example, a motor (not shown) as a drive source that generates the drive force.

[0071] In one embodiment, the lifter 108 is inserted into an insertion hole 119 whose upper end opens in the upper surface 105a of the support 105. The insertion hole 119 is formed, for example, to extend downward from the upper surface of the inner periphery of the support 105 to the bottom surface of the lower outer periphery of the lower electrode 103.

[0072] The edge ring E can be transferred between the wafer support table 101 and the transfer arm 71 of the transfer robot 70 by the lifter 108 as described above. The lifter 108 and the actuator 116 constitute another lifting mechanism that raises and lowers the edge ring E relative to the wafer support table 101 .

[0073] The upper electrode 102 also functions as a gas supply or showerhead that delivers one or more gases from the gas supply mechanism 140 into the chamber 100. In one embodiment, the upper electrode 102 includes a gas inlet 102a, a gas diffusion chamber 102b, and multiple gas outlets 102c. The gas inlet 102a, for example, is in fluid communication with the gas supply mechanism 140 and the gas diffusion chamber 102b. The multiple gas outlets 102c are in fluid communication with the gas diffusion chamber 102b and the interior of the chamber 100. In one embodiment, the upper electrode 102 is configured to deliver gases, such as one or more process gases, from the gas inlet 102a through the gas diffusion chamber 102b and the multiple gas outlets 102c into the chamber 100.

[0074] The gas supply mechanism 140 may include one or more gas sources 141 and one or more flow controllers 142. In one embodiment, the gas supply mechanism 140 is configured to supply, for example, one or more gases from corresponding gas sources 141 to the gas inlet 102a via corresponding flow controllers 142. Each flow controller 142 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply mechanism 140 may include one or more flow modulation devices that modulate or pulse the flow rate of one or more gases.

[0075] The RF power supply 150 is configured to supply RF power, e.g., one or more RF signals, to one or more electrodes, such as the lower electrode 103, the upper electrode 102, or both the lower electrode 103 and the upper electrode 102. This generates a plasma from one or more process gases supplied within the chamber 100, i.e., the processing space 100s. Therefore, the RF power supply 150 may function as at least a part of a plasma generating unit that generates plasma within the chamber 100. The plasma generating unit is specifically configured to generate plasma from one or more gases in the chamber 100. The RF power supply 150 includes, for example, two RF generating units 151a and 151b and two matching circuits 152a and 152b. In one embodiment, the RF power supply 150 is configured to supply a first RF signal from the first RF generating unit 151a to the lower electrode 103 via the first matching circuit 152a. For example, the first RF signal may have a frequency in the range of 27 MHz to 100 MHz.

[0076] In one embodiment, the RF power supply unit 150 is configured to supply a second RF signal from a second RF generating unit 151b to the lower electrode 103 via a second matching circuit 152b. For example, the second RF signal may have a frequency in the range of 400 kHz to 13.56 MHz. Alternatively, a DC (Direct Current) pulse generating unit may be used instead of the second RF generating unit 151b.

[0077] Furthermore, although not shown, other embodiments are contemplated in this disclosure. For example, in an alternative embodiment, the RF power supply 150 may be configured to supply a first RF signal from an RF generator to the lower electrode 103, a second RF signal from another RF generator to the lower electrode 103, and a third RF signal from yet another RF generator to the lower electrode 103. Additionally, in another alternative embodiment, a DC voltage may be applied to the upper electrode 102.

[0078] Still further, in various embodiments, the amplitude of one or more RF signals (i.e., the first RF signal, the second RF signal, etc.) may be pulsed or modulated. Amplitude modulation may include pulsing the RF signal amplitude between an on state and an off state, or between two or more different on states.

[0079] The exhaust system 160 may be connected to, for example, an exhaust port 100e provided at the bottom of the chamber 100. The exhaust system 160 may include a pressure valve and a vacuum pump. The vacuum pump may include a turbomolecular pump, a roughing pump, or a combination thereof.

[0080] <Wafer Processing in Processing Module 60> Next, a description will be given of an example of wafer processing performed using the processing module 60. In the processing module 60, a plasma processing such as an etching process is performed on the wafer W.

[0081] First, the transfer robot 70 loads the wafer W into the chamber 100, and the lifter 107 moves up and down to place the wafer W on the electrostatic chuck 104. Thereafter, a DC voltage is applied from the DC power supply 121a to the electrode 110 of the electrostatic chuck 104, whereby the wafer W is electrostatically attracted and held on the electrostatic chuck 104. After the wafer W is loaded, the inside of the chamber 100 is depressurized to a predetermined vacuum level by the exhaust system 160.

[0082] Next, a processing gas is supplied from the gas supply mechanism 140 to the processing space 100s via the upper electrode 102. Furthermore, high frequency power HF for plasma generation is supplied from the RF power supply unit 150 to the lower electrode 103, thereby exciting the processing gas and generating plasma. At this time, high frequency power LF for ion attraction may also be supplied from the RF power supply unit 150. Then, the generated plasma acts to subject the wafer W to plasma processing.

[0083] During the plasma processing, a DC voltage may be applied to the electrode 111 of the electrostatic chuck 104 from the DC power supplies 121b and 121c, thereby electrostatically attracting and holding the edge ring E on the electrostatic chuck 104. During the plasma processing, a heat transfer gas may be discharged toward the bottom surfaces of the wafer W and the edge ring E attracted and held on the electrostatic chuck 104.

[0084] When the plasma processing is terminated, the supply of high frequency power HF from the RF power supply unit 150 and the supply of processing gas from the gas supply mechanism 140 are stopped. If high frequency power LF has been supplied during the plasma processing, the supply of the high frequency power LF is also stopped. Next, the electrostatic chuck 104 stops attracting and holding the wafer W. In addition, the supply of heat transfer gas to the bottom surface of the wafer W may be stopped.

[0085] Thereafter, the wafer W is raised by the lifter 107, and the wafer W is detached from the electrostatic chuck 104. At the time of this detachment, a charge removal process may be performed on the wafer W. Then, the transfer robot 70 unloads the wafer W from the chamber 100, and the series of wafer processing steps is completed.

[0086] Waferless dry cleaning may be performed after the wafer W is unloaded from the chamber 100. That is, after the wafer W is unloaded from the chamber 100, plasma may be generated in the chamber 100 and the electrostatic chuck 104 may be cleaned by the plasma in a state where the wafer W is not placed on the wafer placement surface of the electrostatic chuck 104. Specifically, after the wafer W is unloaded, a cleaning gas may be supplied from the gas supply mechanism 140 to the processing space 100s via the upper electrode 102 while the wafer W is not placed on the central upper surface 104a of the electrostatic chuck 104, which is the wafer placement surface. Alternatively, for example, high-frequency power HF for plasma generation may be supplied from the RF power supply unit 150 to the lower electrode 103, thereby exciting the gas to generate plasma. The generated plasma can remove reaction products adhering to, for example, a portion between the central portion of the electrostatic chuck 104 and the edge ring E. The high frequency power HF for generating plasma may be supplied to the upper electrode 102.

[0087] <Method for estimating the height of the edge ring E> Next, an example of a method for estimating the height of the edge ring E placed on the electrostatic chuck 104 using the plasma processing system 1 will be described. FIG. 7 is a plan view of an example of a jig wafer serving as a jig substrate used to estimate the height of the edge ring E. FIG. 8 is a flowchart showing an example of a method for estimating the height of the edge ring E. FIG. 9 is a diagram showing the positions of the fork 72 and the distance sensor 73 relative to the wafer support table 101 when estimating the height of the edge ring E. Note that in each of the following steps, the exhaust system 160 continuously evacuates the chamber 100.

[0088] In the plasma processing system 1, the edge ring E mounted on the electrostatic chuck 104 is worn away by the above-described wafer processing using plasma. The degree of wear of the edge ring E can be determined from the height of the edge ring E mounted on the electrostatic chuck 104. Therefore, in the plasma processing system 1, the control device 80 estimates the height of the edge ring E mounted on the electrostatic chuck 104.

[0089] Furthermore, in the plasma processing system 1, when estimating the height of the edge ring E, a jig wafer Wj as shown in FIG. 7 is used. The jig wafer Wj has the same shape and material in a plan view as the wafer W that is actually subjected to plasma processing. The jig wafer Wj and the wafer W are specifically made of silicon, for example. The jig wafer Wj has a reference surface Ws that serves as a reference for the height of the edge ring E, and is placed on the electrostatic chuck 104 so that this reference surface Ws faces upward. Hereinafter, the surface of the jig wafer Wj that faces upward when placed on the electrostatic chuck 104 will be referred to as the upper surface. In one example, the entire upper surface of the jig wafer Wj is formed flat, and the entire upper surface serves as a reference surface Ws. The thickness of the jig wafer Wj may be the same as or different from that of the actual wafer W. The jig wafer Wj is stored in, for example, a storage module 33 when not in use.

[0090] (Step S1) In the plasma processing system 1, when estimating the height of the edge ring E, for example, first, as shown in FIG. 8, under the control of the control device 80, the jig wafer Wj is transported into the chamber 100 by the transport robot 70 and placed on the wafer support table 101 by the lifting mechanism.

[0091] Specifically, for example, first, the jig wafer Wj in the storage module 33 is transported by the transport mechanism 40 and the transport robot 70 into the chamber 100 of the processing module 60 (hereinafter referred to as the processing module 60 to be measured) to which the edge ring E, the height of which is to be measured, is attached.

[0092] More specifically, for example, the jig wafer Wj in the storage module 33 is held by the transfer arm 41 of the transfer mechanism 40 and loaded into the load lock module 20. Next, the load lock module 20 is sealed and depressurized. After that, the interior of the load lock module 20 and the interior of the transfer module 50 are connected to each other. Next, the jig wafer Wj is held by the transfer arm 71 of the transfer robot 70. Also, the gate valve 62 corresponding to the processing module 60 to be measured is opened, and the transfer arm 71 holding the jig wafer Wj is inserted into the chamber 100 through a loading / unloading port (not shown). Then, the jig wafer Wj is transferred by the transfer arm 71 above the upper surface 104a of the central portion of the electrostatic chuck 104.

[0093] Next, the jig wafer Wj is transferred from the transfer robot 70 to the lifter 107. Specifically, the lifter 107 is raised, and the jig wafer Wj is transferred from the transfer arm 71 to the lifter 107. Next, the transfer arm 71 is extracted from the chamber 100, and the gate valve 62 is closed.

[0094] Thereafter, the jig wafer Wj is lowered by the lifting mechanism including the lifter 107 and placed on the upper surface 104a (hereinafter referred to as the wafer placement surface 104a) at the center of the electrostatic chuck 104. Specifically, the lifter 107 is lowered until the upper end of the lifter 107 fits into the insertion hole 115. As a result, the jig wafer Wj is placed on the wafer placement surface 104a.

[0095] (Step S2) Next, under the control of the control device 80, a predetermined voltage is applied to the electrostatic chuck 104 while a predetermined gas is supplied into the chamber 100, and the jig wafer Wj is electrostatically attracted to the wafer mounting surface 104a without plasma. Specifically, for example, the following steps S2a to S2c are performed.

[0096] (Step S2a) In this step, first, a gas for increasing the charge amount is supplied into the chamber 100 . Specifically, an inert gas (nitrogen gas, argon gas, or the like) or oxygen gas is supplied as a charge-increasing gas from the gas supply mechanism 140 into the chamber 100 via the upper electrode . In step S2a, the pressure inside the chamber 100 may be controlled to be 100 mTorr or more. However, if the charge-increasing gas is supplied into the chamber 100, the pressure inside the chamber 100 does not need to be controlled.

[0097] (Step S2b) After step S2a, a predetermined voltage is applied to the electrostatic chuck 104, and the jig wafer Wj is electrostatically attracted to the wafer mounting surface 104a without plasma. Specifically, while the supply of the charge-increasing gas is continued and the RF power supply 150 does not supply the plasma-generating high-frequency power HF, a voltage of 1500 V to 6000 V is applied from the DC power supply 121a to the electrode 110 of the electrostatic chuck 104. As a result, the jig wafer Wj is electrostatically attracted to the central upper surface 104a of the electrostatic chuck 104, which is the wafer mounting surface, without plasma. Furthermore, since the charge-increasing gas is supplied at this time, a phenomenon occurs that is electrically equivalent to the transfer of charge from the chamber 100, which is connected to the ground potential, to the jig wafer Wj via the charge-increasing gas. Therefore, the charge on the jig wafer Wj increases compared to when the charge-increasing gas is not supplied, and the electrostatic attraction force of the jig wafer Wj to the wafer mounting surface 104a becomes stronger.

[0098] (Step S2c) After step S2b, the supply of the predetermined gas is stopped. Specifically, while the jig wafer Wj continues to be electrostatically attracted, the supply of the charge-increasing gas from the gas supply mechanism 140 to the chamber 100 via the upper electrode 102 is stopped.

[0099] (Step S3) Then, under the control of the control device 80, the fork 72 of the transport robot 70 is positioned above the wafer support table 101, and the distance sensor 73 measures the distance to the reference surface Ws of the jig wafer Wj placed on the wafer placement surface 104a and the distance to the edge ring E attached to the wafer support table 101.

[0100] Specifically, while the jig wafer Wj continues to be electrostatically attracted, the gate valve 62 is opened, and the fork 72 is moved above the wafer support table 101 on which the jig wafer Wj and the edge ring E are placed, as shown in FIG. 9. Furthermore, while the jig wafer Wj continues to be electrostatically attracted, the distance from the fork 72 (specifically, the distance sensor 73) positioned above the wafer support table 101 to the reference surface Ws of the jig wafer Wj and the distance from the fork 72 (specifically, the distance sensor 73) to the edge ring E are measured by the distance sensor 73. Specifically, for example, the distance sensor 73 irradiates a predetermined reference position on the reference surface Ws of the jig wafer Wj with distance measurement light, and the reflected light is received by the distance sensor 73. The reference position is, for example, provided at the peripheral edge of the jig wafer Wj. Next, based on the light reception result, the unit controller calculates the distance Lsp from the fork 72 to the predetermined reference position on the reference surface Ws of the jig wafer Wj. Similarly, the distance sensor 73 irradiates a predetermined measurement position on the edge ring E with distance measurement light, and the reflected light is received by the distance sensor 73. The measurement position is provided, for example, at the inner peripheral edge of the edge ring E, that is, the peripheral edge of the edge ring E on the jig wafer W side. Next, based on the light reception result, the unit controller calculates the distance Lf from the fork 72 to the edge ring E. In the following, "the distance from the fork 72 to XX" may be abbreviated to "the distance to XX". Thereafter, the fork 72 is removed from the chamber 100 and the gate valve 62 is closed.

[0101] (Step S4) Next, the control device 80 calculates, or estimates, the height of the edge ring E based on the distance to the reference plane Ws and the distance to the edge ring E. For example, the control device 80 calculates the height H of the edge ring E (specifically, the height from the reference plane Ws) based on the following equation (X) using the distance Lsp and the distance Lf. H=Lsp-Lf …(X)

[0102] (Step S5) Thereafter, under the control of the control device 80, the application of a predetermined voltage to the electrostatic chuck 104, which is used for electrostatically attracting the jig wafer Wj, is stopped. Specifically, the application of voltage from the DC power supply 121a to the electrode 110 of the electrostatic chuck 104 is stopped.

[0103] (Step S6) Subsequently, a static elimination gas is supplied into the chamber 100, and the jig wafer Wj placed on the wafer placement surface 104a is neutralized without using plasma. Specifically, for example, the following steps S6a to S6d are performed.

[0104] (Step S6a) In this step, first, a static elimination gas is supplied into the chamber 100 . Specifically, an inert gas (such as nitrogen gas or argon gas) or oxygen gas is supplied as a static elimination gas from the gas supply mechanism 140 into the chamber 100 via the upper electrode 102. The static elimination gas may be the same as or different from the charge increasing gas. In this step S6a, the pressure inside the chamber 100 may be controlled to be 700 mTorr±100 mTorr.

[0105] (Step S6b) After step S6a, a voltage of a predetermined magnitude and polarity opposite to that of step S2b is applied to the electrostatic chuck 104, and the jig wafer Wj placed on the wafer placement surface 104a is neutralized without plasma. Specifically, while the supply of the static elimination gas into the chamber 100 continues and while the RF power supply unit 150 does not supply the high frequency power HF for generating plasma, a voltage of 100 V to 1500 V, which has a polarity opposite to that of step S2b, is applied from the DC power supply 121a to the electrode 110 of the electrostatic chuck 104. The application of such a voltage of the opposite polarity causes a phenomenon that is electrically equivalent to the electric charge of the jig wafer Wj before the application of the voltage flowing through the gas in the chamber 100 to the ground potential to which the chamber 100 is connected, and the occurrence of this phenomenon is accelerated, so that the jig wafer Wj can be neutralized without plasma. The application time of the reverse polarity voltage is, for example, 5 seconds, and if this application time is exceeded, the application is stopped.

[0106] (Step S6c) After step S6b, with no voltage applied to the electrostatic chuck 104, a static elimination gas is supplied into the chamber 100, and the jig wafer Wj placed on the wafer placement surface 104a is further neutralized. Specifically, following steps S6a and S6b, the supply of the static elimination gas into the chamber 100 continues for a predetermined time with no voltage applied to the electrostatic chuck 104. This causes a phenomenon that is electrically equivalent to the electric charge on the jig wafer Wj flowing to the ground potential to which the chamber 100 is connected via the static elimination gas in the chamber 100, thereby enabling the jig wafer Wj to be further neutralized without plasma. The supply time of the static elimination gas in step S6b is, for example, 30 to 60 seconds. In step S6c, the pressure inside the chamber 100 may be controlled in the same manner as in step S6a. Note that this step S6c may be omitted.

[0107] (Step S6d) After step S6c, the supply of the static elimination gas is stopped. Specifically, the supply of the static elimination gas from the gas supply mechanism 140 into the chamber 100 via the upper electrode 102 is stopped.

[0108] (Step S7) Then, under the control of the control device 80, the jig wafer Wj is separated from the wafer support table 101 by the lifting mechanism, and is carried out of the chamber 100 by the transfer robot .

[0109] Specifically, the jig wafer Wj is raised by the lifting mechanism including the lifter 107 and separated from the wafer placement surface 104a. More specifically, the lifter 107 is raised until the upper end of the lifter 107 protrudes from the wafer mounting surface 104a, thereby separating the jig wafer Wj from the wafer mounting surface 104a. After the separation, the lifter 107 is raised to a predetermined height.

[0110] Next, the jig wafer Wj is transferred from the lifter 107 to the transfer robot 70. Specifically, for example, the gate valve 62 is opened, and the transfer arm 71 of the transfer robot 70 is inserted into the chamber 100. Next, the transfer arm 71 is moved between the jig wafer Wj supported by the lifter 107 and the electrostatic chuck 104. Subsequently, the lifter 107 is lowered, and the jig wafer Wj is transferred to the transfer arm 71.

[0111] Thereafter, the jig wafer Wj in the chamber 100 is returned to the storage module 33 by the transfer robot 70 and the transfer mechanism 40. Specifically, for example, the transfer arm 71 is extracted from the chamber 100, and the jig wafer Wj is transferred from the chamber 100 to the transfer module 50. Next, the gate valve 62 is closed. Thereafter, the interior of the transfer module 50 is connected to the depressurized interior of the load lock module 20. Next, the jig wafer Wj is transferred into the load lock module 20. Next, the interior of the load lock module 20 is sealed and returned to atmospheric pressure. Thereafter, the jig wafer Wj in the load lock module 20 is held by the transfer arm 41 of the transfer mechanism 40 and returned to the storage module 33. This completes the flow of estimating the height of the edge ring E placed on the electrostatic chuck 104 by the plasma processing system 1. The plasma processing system 1 estimates the height of the edge ring E placed on the electrostatic chuck 104, for example, every time a predetermined time period elapses or every time a predetermined number of wafers W are processed.

[0112] <Effects of this embodiment> As described above, in this embodiment, when estimating the height of the edge ring E attached to the wafer support table 101, the jig wafer Wj having a reference plane Ws for the height of the edge ring E is placed on the wafer mounting surface 104a of the wafer support table 101. The control device 80 estimates the height of the edge ring E based on the measurement results of the distance to the reference plane Ws of the jig wafer Wj on the wafer mounting surface 104a and the distance to the edge ring E, which are measured by the distance sensor 73 provided on the fork 72 of the transfer robot 70. Therefore, even if the wafer mounting surface 104a has multiple protrusions 104c as shown in FIG. 6, the height of the edge ring E can be accurately estimated. Furthermore, because the measurement results of the distance to the reference plane Ws are used to estimate the distance to the edge ring E, the height of the edge ring E can be accurately estimated even if the fork 72 sags under its own weight due to changes over time, etc.

[0113] Furthermore, in this embodiment, a predetermined voltage is applied to the electrostatic chuck 104 while a charge-increasing gas is supplied into the chamber 100, and the jig wafer Wj is electrostatically attracted to the wafer mounting surface 104a. Therefore, the amount of charge on the jig wafer Wj when electrostatically attracted to the wafer mounting surface 104a can be increased compared to when a charge-increasing gas is not supplied into the chamber 100 when the predetermined voltage is applied to the electrostatic chuck 104. This point will be described below.

[0114] The wafer mounting surface 104a may become charged before the jig wafer Wj is placed on it. Furthermore, the amount of charge on the wafer mounting surface 104a before the jig wafer Wj is placed on it may vary depending on whether or not the aforementioned waferless cleaning is performed and the details of the waferless cleaning. If this amount of charge varies, the electrostatic attraction force of the jig wafer Wj to the wafer mounting surface 104a also varies. The strength of this electrostatic attraction force affects the height of the reference plane Ws of the jig wafer Wj electrostatically attracted to the wafer mounting surface 104a. In contrast, in this embodiment, the amount of charge on the jig wafer Wj when electrostatically attracted to the wafer mounting surface 104a can be increased as described above, thereby suppressing the effect of differences in the amount of charge on the wafer mounting surface 104a before the jig wafer Wj is placed on the jig wafer Wj on the electrostatic attraction force of the jig wafer Wj to the wafer mounting surface 104a. Therefore, the height of the reference plane Ws of the jig wafer Wj when measuring the distance to the reference plane Ws can be prevented from being affected by differences in the amount of charge on the wafer mounting surface 104a before the jig wafer Wj is placed. Therefore, the estimated height of the edge ring E can be prevented from being affected by differences in the amount of charge on the wafer mounting surface 104a before the jig wafer Wj is placed on the jig wafer Wj.

[0115] Furthermore, in this embodiment, the process of increasing the amount of charge on the jig wafer Wj on the wafer mounting surface 104a in step S2 is performed without plasma. Therefore, the process of increasing the amount of charge on the jig wafer Wj does not cause damage to the reference surface Ws of the jig wafer Wj by plasma. Therefore, it is possible to prevent the accuracy of the estimation result of the height of the edge ring E based on the measurement result of the height of the reference surface Ws from being impaired by the process of increasing the amount of charge on the jig wafer Wj.

[0116] Furthermore, in this embodiment, with the neutralization gas supplied into the chamber 100, a voltage of the opposite polarity to that applied when the jig wafer Wj is attracted to the electrostatic chuck 104 is applied to the electrostatic chuck 104, thereby neutralizing the jig wafer Wj on the wafer mounting surface 104a. Therefore, even if the electrostatic attraction force of the jig wafer Wj to the wafer mounting surface 104a is high due to the process of increasing the charge amount of the jig wafer Wj as described above, the electrostatic attraction force is weakened by the charge removal. This prevents the jig wafer Wj electrostatically attracted to the wafer mounting surface 104a from becoming unable to be removed from the wafer mounting surface 104a. Furthermore, damage to the jig wafer Wj can be prevented when the jig wafer Wj electrostatically attracted to the wafer mounting surface 104a is lifted by the lifting mechanism including the lifter 107 and separated from the wafer mounting surface 104a. In other words, the jig wafer Wj can be used stably when estimating the height of the edge ring E. Furthermore, damage to the lifter 107 can be prevented when the jig wafer Wj electrostatically attracted to the wafer mounting surface 104a is separated from the wafer mounting surface 104a. As described above, the magnitude of the reverse polarity voltage applied to the electrostatic chuck 104 during neutralization is 100 V to 1500 V. By setting the voltage to 100 V or more, it is possible to more reliably prevent the jig wafer Wj from becoming unable to be removed from the wafer mounting surface 104 a. Furthermore, by setting the voltage to 1500 V or less, it is possible to prevent the jig wafer Wj from becoming charged with a polarity opposite to that before neutralization began, which would make it impossible to remove the jig wafer Wj from the wafer mounting surface 104 a.

[0117] Furthermore, the static elimination process of the jig wafer Wj is performed without using plasma. Therefore, the reference surface Ws of the jig wafer Wj, which is used repeatedly, is not damaged by plasma due to the static elimination process of the jig wafer Wj. Therefore, the accuracy of the estimation result of the height of the edge ring E based on the measurement result of the height of the reference surface Ws is prevented from being impaired by the static elimination process of the jig wafer Wj.

[0118] Furthermore, in this embodiment, before the jig wafer Wj is separated from the wafer mounting surface 104a, a neutralization gas is supplied into the chamber 100 while no voltage is applied to the electrostatic chuck 104, and the jig wafer Wj mounted on the wafer mounting surface 104a is neutralized without plasma. Therefore, after neutralization, damage to the lifter 107 and the jig wafer Wj can be more reliably suppressed when the jig wafer Wj is separated from the wafer mounting surface 104a by the lifting mechanism including the lifter 107, and this neutralization process can prevent the reference surface Ws of the jig wafer Wj from being damaged by plasma. The inventors have conducted tests employing the method for separating the jig wafer Wj from the wafer mounting surface 104a according to the present disclosure and have confirmed the following: That is, with this separation method, even when a high voltage of 3000 V is applied to the electrostatic chuck 104 for electrostatically attracting the jig wafer Wj, the jig wafer Wj can be removed from the wafer support table 101 without damaging the jig wafer Wj or the like, and the jig wafer Wj does not move significantly in the horizontal direction during separation. Furthermore, it has been confirmed that these points are independent of the temperature of the chamber 100.

[0119] Furthermore, in this embodiment, the control device 80 estimates the height of the edge ring E based on the measurement results, obtained by the distance sensor 73 provided on the fork 72 of the transfer robot 70, of the distance to a predetermined reference position on the reference surface Ws of the jig wafer Wj on the wafer mounting surface 104a and the distance to a predetermined measurement position on the edge ring E. The reference position is provided on the peripheral edge of the jig wafer Wj, and the measurement position is the peripheral edge of the edge ring E on the jig wafer Wj side, and the reference position and the measurement position are close to each other. Therefore, even if sagging occurs depending on the insertion distance of the fork 72 into the chamber 100, measurement errors caused by the sagging can be suppressed, and the height of the edge ring E can be more accurately estimated.

[0120] (Another example 1 of step S3 and step S4) Figure 10 is a diagram for explaining another example of the process in which the height of the reference surface Ws of the jig wafer Wj and the height of the edge ring E are measured in step S3, and the process in which the control device 80 estimates the height of the edge ring E in step S4.

[0121] When measuring the distance to the edge ring E in step S3, the fork 72 may be moved under the control of the control device 80 so that the distance sensor 73a moves in a predetermined direction, as shown in Fig. 10. The predetermined direction is a direction that crosses the edge ring E in a plan view and intersects with the insertion / removal direction of the fork 72 relative to the chamber 100 (the up-down direction in Fig. 10).

[0122] The method of moving the distance sensor 73a in a direction across the edge ring E in a planar view may be to rotate the fork 72 around the base end of the fork 72 on which the distance sensor 73a is provided, or to rotate the transport arm 71 around the base end of the transport arm 71.

[0123] As described above, the distance sensor 73a may continuously measure the distance Lf to the edge ring E while the distance sensor 73a is moved in a direction across the edge ring E in a plan view. Then, in step S4, the control device 80 may estimate a height distribution, i.e., a profile, of the edge ring E in the crosswise direction based on, for example, the results of continuous measurements of the distance Lsp to a reference point on the reference surface Ws of the jig wafer Wj and the distance Lf to the edge ring E. Specifically, the control device 80 may calculate the height H of the edge ring E for each measurement point of the distance Lf to the edge ring E based on the above formula (X), and create a height distribution of the edge ring E in the crosswise direction from each calculation result and position information of each measurement point. The position information of each measurement point can be calculated from the angle and size of each component of the transfer arm 71 when measuring the distance Lf. In addition, in step S4, the control device 80 may estimate the height of the edge ring E based on the average value of continuous measurement results of the distance Lsp to the reference point on the reference surface Ws of the jig wafer Wj and the distance Lf to the edge ring E.

[0124] (Another example 2 of step S3 and step S4) Incidentally, when the fork 72 is moved so that the distance sensor 73a moves in the crossing direction as in the above-mentioned alternative example 1, the fork 72 may vibrate during the movement. When the fork 72 vibrates, if the height profile of the edge ring E is estimated as in Example 1 above, the profile may be the actual height profile of the edge ring E with the vibration component of the fork 72 superimposed on it.

[0125] In order to eliminate the influence of such vibration components of the fork 72, the following may be done. That is, in step S3, as shown in FIG. 10 , while the fork 72 is being moved so that the one distance sensor 73a moves in a direction across the edge ring E in a plan view, the one distance sensor 73a may continuously measure the distance to the edge ring E. In parallel with this, the other distance sensor 73b may continuously measure the distance to the reference surface Ws of the jig wafer Wj. Then, in step S4, the control device 80 may estimate a height profile D of the edge ring E in the cross direction based on the measurement results of the distance Lft to the edge ring E and the distance Lst to the reference surface Ws at each time point during measurement by the distance sensors 73a and 73b. Specifically, the control device 80 may calculate the height Ht of the edge ring E at each time point during measurement by the distance sensors 73a and 73b based on the difference between the distance Lft and the distance Lst, i.e., based on the following equation (Y): Lst-Lft=Ht …(Y)

[0126] The control device 80 may create a height profile in the crossing direction of the edge ring E from the calculation results of the height Ht at each point in time during measurement by the distance sensors 73a and 73b and the position information of the measurement point by the distance sensor 73a. The profile thus obtained is one in which the influence of the vibration component D2 of the fork 72 has been removed. Furthermore, the profile thus obtained is one in which the influence of the inclination of the fork 72 relative to the wafer support table 101 has been removed.

[0127] (Another example 3 of step S3 and step S4) Furthermore, when measuring the distance to the edge ring E in step S3, the distance sensor 73a may move the fork 72 leftward in a plan view to cross the edge ring E, or the distance sensor 73b may move the fork 72 rightward in a plan view to cross the edge ring E. Note that "left" and "right" in this specification are based on the loading / unloading port of the chamber 100. Furthermore, while the distance sensor 73a is moving leftward, the distance sensor 73a may measure the distance Lsp to a reference point on the left side of the reference surface of the jig wafer Wj, and the distance sensor 73a may continuously measure the distance Lf to the edge ring E on the left side of the edge ring E. In addition, while the distance sensor 73b is moving rightward, the distance sensor 73b may measure the distance to a reference point on the right side of the reference surface of the jig wafer Wj, and the distance sensor 73a may continuously measure the distance Lf to the edge ring E on the right side of the edge ring E.

[0128] Then, in step S4, the control device 80 may estimate a height profile of the left side of the edge ring E in the transverse direction, for example, based on successive measurement results of the distance Lsp to a reference point on the left side of the reference surface of the jig wafer Wj and the distance Lf to the edge ring E on the left side of the edge ring E. Also, in step S4, the control device 80 may estimate a height profile of the right side of the edge ring E in the transverse direction, for example, based on successive measurement results of the distance Lsp to a reference point on the right side of the reference surface of the jig wafer Wj and the distance Lf to the edge ring E on the right side of the edge ring E. Furthermore, the control device 80 may average the height estimation results of corresponding positions in the height profile of the left side of the edge ring E and the height profile of the right side of the edge ring E to generate a representative height profile of the edge ring E.

[0129] In step S4, the control device 80 may estimate the height of the left side of the edge ring E based on an average value of consecutive measurement results of the distance Lsp to a reference point on the left side of the reference surface of the jig wafer Wj and the distance Lf to the edge ring E on the left side of the edge ring E. Furthermore, in step S4, the control device 80 may estimate the height of the right side of the edge ring E based on an average value of consecutive measurement results of the distance Lsp to a reference point on the right side of the reference surface of the jig wafer Wj and the distance Lf to the edge ring E on the right side of the edge ring E. Furthermore, the control device 80 may calculate an average value of the height of the left side of the edge ring E and the height of the right side of the edge ring E, and use the calculation result as the representative height of the edge ring E.

[0130] (Another example 4 of step S4) In step S4, the control device 80 may correct the estimated result of the height of the edge ring E based on the distance Lsp to the reference point on the reference surface Ws of the jig wafer Wj measured by the distance sensor 73 and the design value of the distance Lsp. This makes it possible to remove the influence of the sagging from the estimated result of the height of the edge ring E, even if the fork 72 sags under its own weight due to changes over time or the like. The design value of the distance Lsp is stored in advance in a storage unit (not shown).

[0131] <Another example of a jig wafer> 11 and 12 are a plan view and a cross-sectional view, respectively, that schematically show another example of a jig wafer. As shown in Figures 11 and 12, the jig wafer WjA has multiple correction surfaces Wr spaced a predetermined distance in the height direction from the reference surface Ws, and the multiple correction surfaces Wr have different distances from the reference surface Ws in the height direction. In the example shown in the figure, correction surfaces Wr1 to Wr3 are provided as the correction surface Wr for each of the distance sensor 73a and the distance sensor 73b. The distances of the correction surfaces Wr1 to Wr3 from the reference surface Ws are determined with high precision in advance. In the example shown, the jig wafer WjA has a member WJA1 having step surfaces of different heights provided on the reference surface Ws, and each step surface constitutes the correction surfaces Wr1 to Wr3. However, unlike this example, the jig wafer WjA may have grooves formed in the reference surface Ws with different recess depths, and the bottom surfaces of the grooves may constitute the correction surfaces Wr1 to Wr3. The distances of the correction surfaces Wr1, Wr2, and Wr3 from the reference surface Ws are, for example, 100 μm, 50 μm, and 25 μm, respectively. Furthermore, the member WJA1 of the jig wafer WjA is made of, for example, the same material as the wafer W to be plasma processed, and is used by being adhered to the reference surface Ws.

[0132] When the jig wafer WjA is used, the distance sensor 73 also measures the distances to the multiple correction surfaces Wr when measuring the distance to the reference surface Ws and the distance to the edge ring E. For example, the distance sensor 73 measures the distance to the correction surface Wr1 and the distance to the correction surface Wr2. The control device 80 then corrects the measurement results from the distance sensor 73 based on the measured distances to the multiple correction surfaces Wr. Specifically, the control device 80 calculates, for example, a difference Df between the distance to the correction surface Wr1 and the distance to the correction surface Wr2, both measured by the distance sensor 73. The control device 80 then corrects the measurement results from the distance sensor 73 so that this difference Df approaches a design value for the difference Df. This allows the control device 80 to obtain more accurate distances to the reference surface Ws and the edge ring E, and as a result, to more accurately estimate the height of the edge ring E. The design value for the difference Df is stored in advance in a storage unit (not shown).

[0133] When the height of the edge ring E is estimated using the jig wafer WjA in the manner similar to Alternative Example 2 of Steps S3 and S4 described above, the correction surface Wr is provided in the following region of the jig wafer WjA: That is, the correction surface Wr is provided in a region on the jig wafer WjA where continuous measurement of the distance to the reference surface Ws by the distance sensors 73a and 73b is not hindered when the fork 72 is moved.

[0134] <Confirmation test> FIG. 13 shows the results of a test conducted to confirm the repeatability of the estimation results of the height of the edge ring E using the technology disclosed herein. In this confirmation test, for a processing module 60 in which plasma processing of the edge ring E was repeatedly performed, the height of the edge ring E was estimated at different timings between the plasma processing operations using the method including steps S1 to S7 described above. The timings at which the height of the edge ring E was estimated were when the total time of the plasma processing of the wafer W performed in the corresponding processing module 60 was Z1 to Z7 (Z1 to Z7 are different times, ranging from 0 to 500 hours). In addition, in this confirmation test, the above-mentioned Other Example 2 was adopted for steps S3 and S4, and the jig wafer WjA shown in FIGS. 11 and 12 was used. Furthermore, in this confirmation test, the jig wafer WjA was used in common between the estimation timings, i.e., one jig wafer WjA was used repeatedly. In addition, at each estimation timing, the height of the edge ring E was estimated three times using the method including steps S1 to S7. 13, the horizontal axis indicates the radial position of the edge ring E, and the vertical axis indicates the repeatability of the estimation results of the height of the edge ring E at each estimation timing, specifically, the difference between the maximum and minimum values ​​of the estimated height of the edge ring E at each estimation timing. Note that one division on the vertical axis corresponds to 0.005 m.

[0135] 13, the difference between the maximum and minimum values ​​of the estimated height of the edge ring E was equal to or less than the target value regardless of the estimation timing or the radial position of the edge ring E. In other words, according to the present disclosure, the height of the edge ring E that is consumed by plasma can be estimated with high accuracy over a long period of time without changing the jig wafer Wj.

[0136] <Other variations> One of the correction surfaces Wr of the jig wafer WjA may be used as the reference surface Ws for the height of the edge ring E. Furthermore, the amount of wear of the edge ring E can be determined from the estimated result of the height of the edge ring E. Therefore, when the amount of wear of the edge ring E exceeds a threshold, that is, when the height of the edge ring E falls below the threshold, the edge ring E may be replaced, or a voltage may be applied to the edge ring E to change the shape of the sheath on the edge ring E side.

[0137] When replacing the edge ring E, under the control of the control device 80, the chamber 100 is not opened to the atmosphere, and the edge ring E whose estimated height is below the threshold is separated from the wafer support table 101 by a lifting mechanism including a lifter 108, and is then removed from the chamber 100 by the transport robot 70.

[0138] Specifically, the edge ring E is raised by a lifting mechanism including a lifter 107 and separated from the upper surface (hereinafter, referred to as a ring mounting surface) 104b of the peripheral portion of the electrostatic chuck 104. More specifically, the lifter 108 is raised until the upper end of the lifter 108 protrudes from the ring mounting surface 104b, thereby separating the edge ring E from the ring mounting surface 104b. After the edge ring E is separated from the ring mounting surface 104b, the edge ring E is raised to a predetermined height by the raising of the lifter 108.

[0139] Next, the edge ring E is transferred from the lifter 108 to the transfer robot 70. Specifically, for example, the gate valve 62 is opened, and the transfer arm 71 of the transfer robot 70 is inserted into the chamber 100. Next, the transfer arm 71 is moved between the edge ring E supported by the lifter 108 and the electrostatic chuck 104. Subsequently, the lifter 108 is lowered, and the edge ring E is transferred to the transfer arm 71.

[0140] Thereafter, the edge ring E in the chamber 100 is transferred to the storage module 61 by the transfer robot 70. Specifically, for example, the transfer arm 71 is extracted from the chamber 100, and the edge ring E is transferred from the chamber 100 to the transfer module 50. Next, the gate valve 62 is closed, and the gate valve 63 is opened. Thereafter, the edge ring E is stored in the storage module 61.

[0141] Then, under the control of the control device 80, the replacement edge ring E is transferred into the chamber 100 by the transfer robot 70 and placed on the wafer support table 101 by the lifting mechanism including the lifter 180.

[0142] Specifically, for example, first, the replacement edge ring E in the storage module 61 is held by the transfer arm 71 of the transfer robot 70. Next, the transfer arm 71 holding the edge ring E is inserted into the corresponding chamber 100 through a loading / unloading port (not shown). Then, the edge ring E is transferred by the transfer arm 71 above the ring mounting surface 104b.

[0143] Next, the edge ring E is transferred from the transfer robot 70 to the lifter 108. Specifically, the lifter 108 is raised, and the edge ring E is transferred from the transfer arm 71 to the lifter 108. Next, the transfer arm 71 is extracted from the chamber 100, and the gate valve 62 is closed.

[0144] Thereafter, the edge ring E is lowered by the lifting mechanism including the lifter 107 and placed on the ring placement surface 104b. Specifically, the lifter 108 is lowered until the upper end of the lifter 108 fits into the insertion hole 119. As a result, the edge ring E is placed on the ring placement surface 104b.

[0145] The replacement edge ring E may be a new one, or may be a used one with only a small amount of wear.

[0146] In the above example, the jig wafer Wj is stored in the storage module 33, but it may be stored in the FOUP 31 or the storage module 61.

[0147] In the above example, the storage module 61 serving as a material storage unit for storing the edge ring E is connected to the transfer module 50, but the material storage unit may be connected to one side that constitutes the long side or one side that constitutes the short side of the housing of the loader module 30. Also, the FOUP 31 placed on the load port 32 may be the material storage unit. In these cases, the transport mechanism 40 may be configured to be able to transport the edge ring E for replacement.

[0148] 14, in addition to the edge ring E, a cover ring C arranged to cover the outer surface of the edge ring E may be attached to the wafer support table as an annular member. The technology of the present disclosure can also be applied to estimating the height of the cover ring C attached to the wafer support table.

[0149] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. For example, the components of the above-described embodiments may be arbitrarily combined. Such an arbitrary combination naturally provides the functions and effects of each of the components involved in the combination, and also provides other functions and effects that are apparent to those skilled in the art from the description of this specification.

[0150] Furthermore, the effects described herein are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that would be apparent to a person skilled in the art from the description of this specification, in addition to or in place of the above-described effects.

[0151] Note that the following configuration examples also fall within the technical scope of the present disclosure. (1) A plasma processing system, comprising: a plasma processing apparatus; a reduced pressure transfer apparatus connected to the plasma processing apparatus and having a transfer robot for transferring a substrate; and a control apparatus; The plasma processing apparatus includes: a processing container configured to be decompressible; a substrate support table provided in the processing chamber, the substrate support table having a substrate mounting surface and an electrostatic chuck that electrostatically attracts a substrate to the substrate mounting surface, the substrate support table having an annular member attached to the substrate mounting surface so as to surround the substrate mounting surface; a lifting mechanism for lifting and lowering the substrate relative to the substrate placement surface; a gas supply unit that supplies a gas into the processing chamber, The transport robot is a holder configured to be able to hold a substrate to be transported; a distance sensor provided in the holding portion and measuring a distance from the holding portion, The control device (A) carrying a jig substrate having a reference surface that serves as a reference for the height of the annular member into the processing chamber by the transfer robot, and placing the jig substrate on the substrate support table by the lifting mechanism; (B) applying a voltage to the electrostatic chuck while the gas is being supplied into the processing chamber, thereby adsorbing the jig substrate onto the substrate mounting surface in a plasmaless manner; (C) positioning the holding unit of the transport robot above the substrate support table, and measuring, with the distance sensor, the distance to the reference surface of the jig substrate placed on the substrate placement surface and the distance to the annular member attached to the substrate support table; (D) estimating a height of the annular member based on the measurement results of the distance to the reference surface and the distance to the annular member. (2) The control device (E) supplying the gas into the processing vessel and removing electricity from the jig substrate placed on the substrate placement surface in a plasma-less manner; (F) after the step (E), further performing the step of separating the jig substrate from the substrate support table by the lifting mechanism and unloading the jig substrate from the processing chamber by the transfer robot; The plasma processing system according to (1), wherein the step (E) includes the step of (G) supplying the gas into the processing vessel while applying a voltage of a polarity opposite to that in the step (B) to the electrostatic chuck, thereby plasmalessly de-electrifying the jig substrate placed on the substrate placement surface. (3) The plasma processing system according to (2), wherein the step (E) includes the step (H) of supplying the gas into the processing vessel while no voltage is applied to the electrostatic chuck, thereby removing electricity from the jig substrate placed on the substrate placement surface without applying plasma. (4) The plasma processing system according to (3), wherein the step (H) is performed after the step (G). (5) The plasma processing system according to any one of (1) to (4), wherein the gas is an inert gas or an oxygen gas. (6) The plasma processing apparatus further includes another lifting mechanism for lifting the annular member relative to the substrate support table; the transport robot is configured to also transport the annular member; The control device (I) when the height of the annular member estimated in the step (D) is below a threshold, moving the annular member away from the substrate support table by the separate lifting mechanism and carrying the annular member out of the processing chamber by the transfer robot; (J) after step (I), the plasma processing system further executes the step of carrying a replacement annular member into the processing vessel by the transfer robot and placing it on the substrate support table by the separate lifting mechanism. (7) A member storage unit for storing the annular member is further provided, The plasma processing system according to any one of (1) to (6), wherein the member storage unit is connected to the reduced pressure transfer device. (8) an atmospheric pressure transfer device connected to the reduced pressure transfer device via a load lock device configured to switch the interior between atmospheric pressure and reduced pressure atmosphere, and having a transfer mechanism that operates under atmospheric pressure and transfers substrates; The plasma processing system according to any one of (1) to (6), further comprising a member storage unit connected to the atmospheric pressure transfer device and configured to store the annular member. (9) The plasma processing system according to (7) or (8), wherein the jig substrate is stored in the member storage unit. (10) An atmospheric section is further provided which is connected to the reduced pressure transport device via a load lock device configured to switch the inside between an atmospheric pressure atmosphere and a reduced pressure atmosphere and which operates under an atmospheric pressure atmosphere, The jig substrate is The substrates are stored in a storage container placed in the atmospheric section and configured to be able to store a plurality of substrates, or The plasma processing system according to any one of (1) to (9), wherein the substrates are stored in a substrate storage unit provided in the atmospheric unit separately from the storage container. (11) The plasma processing system according to any one of (1) to (10), wherein the annular member is an edge ring arranged adjacent to the substrate on the substrate support table, or a cover ring arranged to cover the outer surface of the edge ring. (12) In the step (C), the holding unit is moved above the substrate support table so that the distance sensor crosses the annular member in a plan view, and the distance sensor measures the distance to the reference surface of the jig substrate placed on the substrate placement surface, and continuously measures the distance to the annular member attached to the substrate support table; The plasma processing system according to any one of (1) to (11), wherein the step (D) estimates a height profile of the annular member in the transverse direction based on the measurement results of the distance to the reference surface in the step (C) and the continuous measurement results up to the annular member. (13) A method for estimating the height of an annular member in a plasma processing system, comprising: the plasma processing system includes: a plasma processing apparatus; and a reduced pressure transfer apparatus connected to the plasma processing apparatus and having a transfer robot for transferring a substrate, The plasma processing apparatus includes: a processing container configured to be decompressible; a substrate support table provided in the processing chamber, the substrate support table having a substrate mounting surface and an electrostatic chuck that electrostatically attracts a substrate to the substrate mounting surface, the annular member being attached to the substrate mounting surface so as to surround the substrate mounting surface; a lifting mechanism for lifting and lowering the substrate relative to the substrate placement surface, The transport robot is a holder configured to be able to hold a substrate to be transported; a distance sensor provided in the holding portion and measuring a distance from the holding portion, (A) carrying a jig substrate having a reference surface that serves as a reference for the height of the annular member into the processing chamber by the transfer robot, and placing the jig substrate on the substrate support table by the lifting mechanism; (B) applying a voltage to the electrostatic chuck while supplying gas into the processing chamber, thereby adsorbing the jig substrate onto the substrate mounting surface in a plasmaless manner; (C) positioning the holding unit of the transport robot above the substrate support table, and measuring, with the distance sensor, the distance to the reference surface of the jig substrate placed on the substrate placement surface and the distance to the annular member attached to the substrate support table; (D) estimating the height of the annular member based on the measurement results of the distance to the reference plane and the distance to the annular member. [Explanation of symbols]

[0152] 1. Plasma Processing System 50 Transfer Module 60 Processing Modules 70 Transport Robot 72 Fork 73, 73a, 73b distance sensors 80 Control device 100 Chambers 101 wafer support 102 Upper electrode 104 Electrostatic Chuck 104a: Upper surface of the center of the electrostatic chuck (wafer mounting surface) 107 Lifter E Edge Ring W wafer Wj, WjA Jig wafer

Claims

1. 1. A plasma processing system comprising: a plasma processing apparatus; a reduced pressure transfer apparatus connected to the plasma processing apparatus and having a transfer robot for transferring a substrate; and a control apparatus; The plasma processing apparatus includes: a processing container configured to be decompressible; a substrate support table provided in the processing chamber, the substrate support table having a substrate mounting surface and an electrostatic chuck that electrostatically attracts a substrate to the substrate mounting surface, the substrate support table having an annular member attached to the substrate mounting surface so as to surround the substrate mounting surface; a lifting mechanism for lifting and lowering the substrate relative to the substrate placement surface; a gas supply unit that supplies a gas into the processing chamber, The transport robot is a holder configured to be able to hold a substrate to be transported; a distance sensor provided in the holding portion and measuring a distance from the holding portion, The control device (A) carrying a jig substrate having a reference surface that serves as a reference for the height of the annular member into the processing chamber by the transfer robot, and placing the jig substrate on the substrate support table by the lifting mechanism; (B) applying a voltage to the electrostatic chuck while the gas is being supplied into the processing vessel, thereby adsorbing the jig substrate to the substrate mounting surface in a plasma-less manner; (C) positioning the holding unit of the transport robot above the substrate support table, and measuring, with the distance sensor, the distance to the reference surface of the jig substrate placed on the substrate placement surface and the distance to the annular member attached to the substrate support table; (D) estimating a height of the annular member based on the measurement results of the distance to the reference surface and the distance to the annular member.

2. The control device (E) supplying the gas into the processing vessel and neutralizing the jig substrate placed on the substrate placement surface in a plasma-less manner; (F) after the step (E), further performing the step of separating the jig substrate from the substrate support table by the lifting mechanism and unloading the jig substrate from the processing chamber by the transfer robot; 2. The plasma processing system of claim 1, wherein the step (E) includes the step of: (G) supplying the gas into the processing vessel while applying a voltage having a polarity opposite to that in the step (B) to the electrostatic chuck, thereby plasmalessly de-electrifying the jig substrate placed on the substrate placement surface.

3. 3. The plasma processing system of claim 2, wherein the step (E) includes the step (H) of supplying the gas into the processing vessel while no voltage is applied to the electrostatic chuck, thereby removing electricity from the jig substrate placed on the substrate placement surface in a plasma-less manner.

4. The plasma processing system of claim 3 , wherein the step (H) is performed after the step (G).

5. 5. The plasma processing system of claim 1, wherein the gas is an inert gas or an oxygen gas.

6. the plasma processing apparatus further includes another lifting mechanism that raises and lowers the annular member relative to the substrate support table; the transport robot is configured to also transport the annular member; The control device (I) when the height of the annular member estimated in the step (D) is below a threshold value, moving the annular member away from the substrate support table by the separate lifting mechanism and unloading the annular member from the processing chamber by the transfer robot; 5. The plasma processing system of claim 1, further comprising: (J) after step (I), carrying a replacement annular member into the processing vessel by the transfer robot, and placing the replacement annular member on the substrate support table by the separate lifting mechanism.

7. Further provided is a member storage unit that stores the annular member, The plasma processing system of claim 1 , wherein the material storage unit is connected to the reduced pressure transfer device.

8. an atmospheric pressure transfer device connected to the reduced pressure transfer device via a load lock device configured to be able to switch the interior between atmospheric pressure and reduced pressure atmosphere, and having a transfer mechanism that operates under atmospheric pressure and transfers substrates; 2. The plasma processing system of claim 1, further comprising: a member storage unit connected to the atmospheric pressure transfer device and configured to store the annular member.

9. 9. The plasma processing system according to claim 7, wherein the jig substrate is stored in the member storage section.

10. an atmospheric section connected to the reduced-pressure transfer device via a load lock device configured to be able to switch the interior between an atmospheric pressure atmosphere and a reduced-pressure atmosphere, and operating under an atmospheric pressure atmosphere; The jig substrate is The substrates are stored in a storage container placed in the atmospheric section and configured to be able to store a plurality of substrates, or 9. The plasma processing system according to claim 1, wherein the substrates are stored in a substrate storage section provided in the atmospheric section separately from the storage container.

11. 9. The plasma processing system according to claim 1, wherein the annular member is an edge ring disposed adjacent to the substrate on the substrate support table, or a cover ring disposed to cover the outer surface of the edge ring.

12. The step (C) comprises moving the holding unit above the substrate support table so that the distance sensor crosses the annular member in a plan view, and measuring the distance to the reference surface of the jig substrate placed on the substrate placement surface using the distance sensor, and continuously measuring the distance to the annular member attached to the substrate support table; 9. The plasma processing system according to claim 1, wherein the step (D) estimates a height profile of the annular member in the transverse direction based on the measurement results of the distance to the reference surface in the step (C) and the continuous measurement results up to the annular member.

13. 1. A method for estimating a height of an annular member in a plasma processing system, comprising: the plasma processing system includes: a plasma processing apparatus; and a reduced pressure transfer apparatus connected to the plasma processing apparatus and having a transfer robot for transferring a substrate, The plasma processing apparatus includes: a processing container configured to be decompressible; a substrate support table provided in the processing chamber, the substrate support table having a substrate mounting surface and an electrostatic chuck that electrostatically attracts a substrate to the substrate mounting surface, the annular member being attached to the substrate mounting surface so as to surround the substrate mounting surface; a lifting mechanism for lifting and lowering the substrate relative to the substrate placement surface, The transport robot is a holder configured to be able to hold a substrate to be transported; a distance sensor provided in the holding portion and measuring a distance from the holding portion, (A) carrying a jig substrate having a reference surface that serves as a reference for the height of the annular member into the processing chamber by the transfer robot, and placing the jig substrate on the substrate support table by the lifting mechanism; (B) applying a voltage to the electrostatic chuck while supplying gas into the processing chamber, thereby adsorbing the jig substrate to the substrate mounting surface in a plasma-less manner; (C) positioning the holding unit of the transport robot above the substrate support table, and measuring, with the distance sensor, the distance to the reference surface of the jig substrate placed on the substrate placement surface and the distance to the annular member attached to the substrate support table; (D) A method for estimating the height of the annular member, comprising a step of estimating the height of the annular member based on the measurement results of the distance to the reference plane and the distance to the annular member.

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