Plasma processing apparatus and detection method

Abstract

To provide a plasma processing apparatus detecting both the state of a substrate mounted on a substrate mounting plane of a mounting table or the state of the substrate mounting plane of the mounting table and the state of an edge ring mounted on the mounting table while upsizing of an apparatus and an increase in cost are suppressed, and a method of detection.SOLUTION: A plasma processing apparatus 1 applying plasma processing to a substrate W includes: a processing container 100 housing a substrate; a mounting table 101 which is provided in the processing container and has a substrate mounting plane 103a mounting the substrate and a ring mounting plane 103b mounting an edge ring E that is disposed to surround the substrate; a first sensor 150 detecting the state of the substrate to be the substrate mounting plane of the mounting table or the state of the substrate mounting plane; a second sensor 160 detecting the state of the edge ring to be a ring mounting plane of the mounting table; and a holding part 170 which is provided in the processing container and holds a first sensor and a second sensor.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a plasma processing apparatus and a detection method. [Background technology]

[0002] Patent Document 1 discloses a substrate processing apparatus including an annular member having an annular member main body placed around a substrate in the substrate processing apparatus, an annular member having a dissimilar material portion provided in the annular member main body and formed from a dissimilar material different from the material of the annular member main body, and a detector for detecting products resulting from the dissimilar material. This substrate processing apparatus further includes a control unit that determines the wear state of the annular member based on the detection value of the detector. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-40076 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology disclosed herein makes it possible to detect both the state of a substrate placed on the substrate placement surface of a placement table or the state of the substrate placement surface of the placement table, and the state of an edge ring placed on the placement table, while preventing the device from becoming larger or more expensive. [Means for solving the problem]

[0005] One aspect of the present disclosure is a plasma processing apparatus for performing plasma processing on a substrate, the plasma processing apparatus comprising: a processing vessel for accommodating the substrate; a mounting table provided in the processing vessel, the mounting table having a substrate mounting surface on which the substrate is mounted and a ring mounting surface on which an edge ring is mounted so as to surround the substrate; Placement a first sensor for detecting a state of the substrate or a state of the substrate mounting surface; Placementa second sensor that detects the state of the edge ring that has been placed on the wafer; a holding unit that is provided within the processing vessel and that holds the first sensor and the second sensor; and a moving mechanism that moves the holding unit to move the first sensor and the second sensor between a processing region above the mounting table and an evacuation region that is located outside the processing region in a top view within the processing vessel and is common to all sensors. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to detect both the state of a substrate placed on the substrate placement surface of a placement table or the state of the substrate placement surface of the placement table, and the state of an edge ring placed on the placement table, while suppressing increases in the size and cost of the device. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a longitudinal sectional view schematically showing the configuration of a plasma processing apparatus according to an embodiment of the present invention, illustrating a state during plasma processing. [Figure 2] 1 is a longitudinal sectional view schematically showing the outline of the configuration of a plasma processing apparatus according to this embodiment, illustrating a state when detecting the state of an edge ring or the like. [Figure 3] FIG. 2 is a cross-sectional view of the plasma processing apparatus of FIG. [Figure 4] FIG. 2 is a partially enlarged cross-sectional view of the electrostatic chuck. [Figure 5] 10A and 10B are diagrams illustrating another example of a movement mechanism that moves the arms that hold the first sensor and the second sensor. DETAILED DESCRIPTION OF THE INVENTION

[0008] In the manufacturing process of semiconductor devices, substrates such as semiconductor wafers (hereinafter referred to as "wafers") are subjected to substrate processing using plasma, i.e., plasma processing, by a plasma processing apparatus. This plasma processing is performed with the substrate placed on a mounting table inside a depressurized processing chamber.

[0009] In order to obtain good and uniform plasma processing results at the center and peripheral edges of the substrate, a ring-shaped component in plan view, known as a focus ring, edge ring, etc. (hereinafter referred to as an "edge ring"), may be placed on the substrate support table so as to surround the periphery of the substrate on the support table.

[0010] This edge ring is etched and worn away by exposure to plasma. When the edge ring is worn away, it can lead to inappropriate plasma processing results. Specifically, when the edge ring is worn away, the shape of the plasma sheath changes, which can result in inappropriate plasma processing results. Therefore, in order to replace the edge ring at the appropriate time, a sensor is used to detect the state of the edge ring, and the degree of wear of the edge ring is estimated from the sensor's detection results (e.g., the detection results of the distance from the sensor to the edge ring).

[0011] Furthermore, in a plasma processing apparatus, it would be useful if it were possible to detect the condition of a substrate placed on the substrate placing surface of a placing table, such as the thickness of the film to be etched on the substrate after plasma processing, or the condition of the substrate placing surface, such as the presence or absence of particles on the substrate placing surface of the placing table.

[0012] However, simply providing both a sensor that detects the state of the substrate placed on the substrate mounting surface of the mounting table or the state of the substrate mounting surface of the mounting table, and a sensor that detects the state of the edge ring placed on the mounting table, would result in an increase in the size and cost of the device.

[0013] Therefore, the technology disclosed herein makes it possible to detect the state of a substrate placed on the substrate placement surface of a placement table or the state of the substrate placement surface of the placement table, and the state of an edge ring placed on the placement table, while preventing the device from becoming larger or more expensive.

[0014] Hereinafter, a plasma processing apparatus and a detection method according to the present embodiment will be described with reference to the drawings. In this specification, elements having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0015] <Plasma processing equipment> 1 and 2 are longitudinal sectional views schematically showing the configuration of a plasma processing apparatus according to this embodiment. Fig. 1 shows the state during plasma processing, and Fig. 2 shows the state when detecting the state of an edge ring, etc. Fig. 3 is a transverse sectional view of the plasma processing apparatus of Fig. 1. Fig. 4 is a partially enlarged sectional view of an electrostatic chuck, which will be described later.

[0016] 1 to 3 etches a film on the surface of a wafer W serving as a substrate, and more specifically, cleans the surface of the wafer W by reverse sputtering. More specifically, the plasma processing apparatus 1 removes a natural oxide film formed on the surface of the wafer W as a pretreatment for a film formation process such as PVD or CVD.

[0017] As shown in FIGS. 1 and 2, the plasma processing apparatus 1 includes a processing chamber 100, a gas supply unit 110, an RF (Radio Frequency) power supply unit 120, and an exhaust system .

[0018] The processing vessel 100 is a vessel configured so that the inside can be depressurized, and accommodates the wafer W. The processing vessel 100 is made of a conductive material such as aluminum. The processing vessel 100 is also grounded.

[0019] A loading / unloading port (not shown) for the wafer W is provided on the sidewall of the processing chamber 100, and a gate valve for opening and closing the loading / unloading port is provided at the loading / unloading port.

[0020] A mounting table 101 that supports a wafer W is provided within the processing vessel 100. The mounting table 101 includes, for example, a lower electrode 102, an electrostatic chuck 103, and an insulator 104. The mounting table 101 is also configured to support an edge ring E. The mounting table 101 may or may not include the edge ring E as a component thereof.

[0021] The lower electrode 102 is made of a conductive material such as aluminum.

[0022] The electrostatic chuck 103 is provided on the lower electrode 102 and attracts and holds the wafer W by electrostatic force. The electrostatic chuck 103 is formed, for example, so that an upper surface 103a at the center is higher than an upper surface 103b at the peripheral edge. In one embodiment, the upper surface 103a at the center of the electrostatic chuck 103 serves as a wafer mounting surface on which the wafer W is mounted, and the upper surface 103b at the peripheral edge of the electrostatic chuck 103 serves as a ring mounting surface on which an edge ring E is mounted.

[0023] The edge ring E is a member having an annular shape in a plan view (specifically, a circular annular shape in a plan view), and is disposed so as to surround the wafer W placed on the upper surface 103a at the center of the electrostatic chuck 103, for example, to improve the uniformity of the plasma processing (in this example, a reverse sputtering process using plasma). The edge ring E is made of, for example, silicon.

[0024] 4, a plurality of protrusions 103c may be provided on the top surface 103a at the center of the electrostatic chuck 103. This prevents the wafer W from continuing to be attracted to the electrostatic chuck 103 due to a residual attracting force when the application of a voltage to the electrostatic chuck 103 for electrostatically attracting the wafer W to the electrostatic chuck 103 is stopped. The plurality of protrusions 103c are provided, for example, at equal intervals. The protrusions 103c 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.

[0025] 1 and 2, the insulator 104 supports the lower electrode 102. The insulator 104 is, for example, a cylindrical member having an outer diameter equal to that of the lower electrode 102, and is made of ceramic or the like, and supports the peripheral edge side of the lower electrode 102.

[0026] Further, the mounting table 101 is provided with lifting pins (not shown) for transferring the wafer W between the mounting table 101 and the outside of the plasma processing apparatus 1. The lifting pins move up and down so as to protrude from and retract into the upper surface 103a of the central portion of the electrostatic chuck 103.

[0027] The gas supply unit 110 includes one or more gas supply sources 111 and one or more flow rate controllers 112, and is connected to a gas introduction pipe 113. The gas supply unit 110 is configured to supply, for example, one or more process gases from the corresponding gas supply sources 111 into the process vessel 100 via the corresponding flow rate controllers 112 and gas introduction pipes 113.

[0028] The RF power supply unit 120 includes, for example, an RF generation unit 121 and a matching circuit 122. The RF generation unit 121 is connected to the lower electrode 102 via the matching circuit 122, and generates and supplies RF power to the lower electrode 102. The matching circuit 122 has a circuit for matching the output impedance of the RF generation unit 121 with the input impedance on the load (lower electrode 102) side.

[0029] The RF power supplied by the RF power supply unit 120 generates plasma from the processing gas supplied into the processing vessel 100. That is, the RF power supply unit 120 can function as at least a part of a plasma generating unit that generates plasma in the processing vessel 100.

[0030] The exhaust system 130 includes a vacuum pump (not shown) and exhausts the inside of the processing vessel 100. The exhaust system 130 is connected to one end of an exhaust pipe 131, the other end of which is connected to the processing vessel 100.

[0031] Furthermore, the plasma processing apparatus 1 includes a shield member 140 . The shield member 140 is provided above the mounting table 101 in the processing vessel 100 to prevent particles generated during plasma processing from adhering to the inner wall of the processing vessel 100. In addition, the shield member 140 forms a processing space K between the mounting table 101 and the shield member 140.

[0032] The shield member 140 includes, for example, an upper shield 141 and a lower shield 142 .

[0033] The upper shield 141 is fixed above the mounting table 101 in the processing vessel 100 via, for example, a fixing member (not shown). The upper shield 141 is formed in a cylindrical shape with a cover, and a circular protrusion 143 that protrudes downward is formed along the periphery of the upper shield 141. A circular recess 144 is formed along the protrusion 143 in the upper shield 141. The recess 144 is formed to be recessed upward.

[0034] The lower shield 142 is configured to be movable up and down within the processing vessel 100 by an elevation mechanism (not shown). The lower shield 142 has a main body 145 and a protrusion 146. The main body 145 is formed in an annular shape with an outer diameter that is approximately the same as that of the upper shield 141. The protrusion 146 is formed in an annular shape along the main body 145, and is formed so as to protrude upward at a position on the top surface of the main body 145 that corresponds to the recess 144 of the upper shield 141.

[0035] 1, only the upper end of the convex portion 146 of the lower shield 142 is inserted into the concave portion 144 of the upper shield 141, and a processing space K is formed between the mounting table 101 and the shield member 140. On the other hand, when the lower shield 142 is in the upper transfer position shown in FIG. 2, a gap is formed between the mounting table 101 and the lower end of the bottom shield 142, and a wafer W is loaded onto the mounting table 101 and a first sensor 150 and a second sensor 160, which will be described later, are moved above the mounting table 101 through this gap. Note that when the bottom shield 142 is in the transfer position, substantially the entirety of the convex portion 146 of the bottom shield 142 is inserted into the concave portion 144 of the upper shield 141.

[0036] Furthermore, the plasma processing apparatus 1 includes a first sensor 150, a second sensor 160, an arm 170 as a holder, and a moving mechanism 180.

[0037] The first sensor 150 detects the state of the wafer W placed on the central upper surface (hereinafter referred to as the wafer placement surface) 103a of the electrostatic chuck 103, and is provided in the processing vessel 100. The first sensor 150 detects, as the state of the wafer W, for example, the thickness of a film formed on the surface of the wafer W, and more specifically, the thickness of a native oxide film on the surface of the wafer W. The first sensor 150 also detects the thickness of the native oxide film or the like on the surface of the wafer W in a non-contact manner using, for example, light, and more specifically, by reflection spectroscopy.

[0038] The second sensor 160 detects the state of the edge ring E mounted on the upper surface (hereinafter, referred to as the ring mounting surface) 103b of the peripheral portion of the electrostatic chuck 103, and is provided in the processing vessel 100. The second sensor 160 detects, for example, information regarding the amount of wear of the edge ring E as the state of the edge ring E, and more specifically, detects the distance from the second sensor 160 to the edge ring E, which corresponds to the amount of wear. The second sensor 160 also detects the distance to the edge ring E in a non-contact manner using, for example, light, and more specifically, detects the distance using, for example, an optical interference method.

[0039] The arm 170 holds the first sensor 150 and the second sensor 160 and is provided inside the processing vessel 100. The arm 170 includes, for example, a first arm 171 that holds the first sensor 150 and a second arm 172 that holds the second sensor 160.

[0040] The first arm 171 and the second arm 172 are each formed in a hollow rectangular parallelepiped shape and are provided so as to extend toward the center of the mounting table 101 (specifically, the center of the electrostatic chuck 103) as shown in FIG. 3. The hollow portions inside the first arm 171 and the second arm 172 are each maintained at atmospheric pressure. As shown in FIGS. 1 and 2, the first arm 171 is supported from below by the second arm 172. In one embodiment, the first arm 171 is supported and fixed from below by the second arm 172 so as to be aligned in a straight line with the second arm 172.

[0041] First sensor 150 is fixed in an internal cavity at the tip side of first arm 171. Furthermore, first arm 171 is provided with an optical window 173 that transmits light for detection by first sensor 150 in a portion corresponding to first sensor 150. Specifically, an opening (not shown) is formed in the lower part of first arm 171 at a position corresponding to first sensor 150, and this opening is sealed by optical window 173. The base end side of first arm 171 is fixed to second arm 172, for example.

[0042] A second sensor 160 is fixed to an internal cavity at the tip side of the second arm 172. An optical window 174 that transmits light for detection by the second sensor 160 is provided in the second arm 172 at a portion corresponding to the second sensor 160. Specifically, an opening (not shown) is formed in the lower part of the second arm 172 at a position corresponding to the second sensor 160, and this opening is sealed by the optical window 174. The second arm 172 is fixed to a guide member 182 (described later) of the movement mechanism 180 so as to be movable, for example, in the direction in which the second arm 172 extends. The internal cavity of the second arm 172 and the cavity of the first arm 171 are in communication with each other.

[0043] In order to prevent the tips of the first arm 171 and the second arm 172 from sagging, it is preferable that the thickness of each arm be, for example, 10 mm or less.

[0044] The optical windows 173 and 174 may be made of, for example, quartz (transmitting wavelength of, for example, 165 to 2600 nm) or barium fluoride (transmitting wavelength of, for example, 150 to 1300 nm).

[0045] A cable 175 for transmitting signals between the first sensor 150 and the second sensor 160 and the outside of the processing vessel 100 passes through the inside of the arm 170, which is maintained at atmospheric pressure, and is arranged to reach the outside of the processing vessel 100, which is maintained at vacuum during plasma processing. The cable 175 includes a cable for communicating signals between the first sensor 150 and the outside of the processing vessel 100, and a cable for communicating signals between the second sensor 160 and the outside of the processing vessel 100.

[0046] The former cable, for example, passes through the inside of the first arm 171 and the inside of the second arm 172, and reaches the inside of the processing vessel 100 via a hermetic seal 176 provided on the base end side of the second arm 172 (the side opposite the mounting table 101) that seals the inside of the second arm 172 from the outside of the processing vessel 100, and the side opposite the arm 170 is led out of the processing vessel 100. The latter cable, for example, passes through the inside of the second arm 172 and reaches the inside of the processing vessel 100 via a hermetic seal 176 provided on the base end side of the second arm 172, and the end opposite to the arm 170 is led out of the processing vessel 100.

[0047] The movement mechanism 180 moves the arm 170 linearly, thereby moving the first sensor 150 and the second sensor 160 between a processing region R1 above the mounting table 101 and a retraction region R2 common to the sensors, which is located outside the processing region R1 in a top view within the processing vessel 100. Specifically, the movement mechanism 180 moves the arm 170 linearly in a direction in which the arm 170 (more specifically, the first arm 171 and the second arm 172) extend (hereinafter, referred to as the arm extension direction), thereby moving the first sensor 150 and the second sensor 160 between the processing region R1 and the retraction region R2 common to the first sensor 150 and the second sensor 160.

[0048] The movement mechanism 180 includes a base 181 and a guide member 182 . The base 181 supports the guide member 182. The base 181 itself is supported by the bottom wall of the processing vessel 100, for example. Guide member 182 guides the linear movement of arm 170, and has, for example, a guide groove 183 extending in the arm extension direction. When second arm 172 moves along guide groove 183, the entire arm 170 moves in the arm extension direction.

[0049] Furthermore, the movement mechanism 180 has a drive source (not shown) that generates a drive force to move the arm 170 along the guide member 182. For example, an air cylinder may be used as the drive source.

[0050] Furthermore, the plasma processing apparatus 1 includes a control unit M. The control unit M includes a computer equipped with a processor such as a CPU, a memory, and the like, and has a storage unit (not shown) that stores various information. The storage unit stores a program for controlling wafer processing using the plasma processing apparatus 1 and a program for detecting the state of the edge ring E and the state of the wafer W placed on the wafer placement surface 103a. The program may be recorded on a computer-readable storage medium and installed into the control unit M from the storage medium. The storage medium may be a temporary storage medium or a non-temporary storage medium.

[0051] The control unit M further includes a display unit M1 as a notification unit. The display unit M1 displays various types of information and is configured by a display device such as a liquid crystal display or an organic display.

[0052] <Wafer processing> Next, a description will be given of an example of wafer processing using the plasma processing apparatus 1. Note that the following steps are performed under the control of the control unit M. First, with the lower shield 142 of the shield member 140 in the transfer position, the wafer W held by a transfer mechanism (not shown) is inserted into the processing vessel 100 from a vacuum transfer chamber (not shown) adjacent to the processing vessel 100 through a loading / unloading port (not shown). Then, the wafer W is placed on the wafer placement surface 103a of the placement table 101 via the lift pins.

[0053] Next, the lower shield 142 of the shield member 140 is lowered and moved to the processing position, and the processing space K is formed.

[0054] In this state, the wafer W is subjected to a process using plasma, i.e., a plasma process, specifically an etching process using plasma (more specifically, a reverse sputtering process using plasma). Specifically, a process gas such as Ar gas is supplied from the gas supply unit 110 into the process vessel 100 (specifically, into the process space K), and high-frequency power for plasma generation is supplied from the RF power supply unit 120 to the lower electrode 102. This excites the process gas and generates plasma. At this time, bias RF power for attracting ions to the wafer W may be supplied to the mounting table 101 (specifically, the lower electrode 102). Then, the generated plasma reverse-sputters the surface of the wafer W mounted on the wafer mounting surface 103a, i.e., removes a native oxide film on the surface layer of the wafer W.

[0055] After the plasma etching process is completed, the wafer W is unloaded from the processing vessel 100 to a transfer chamber (not shown) in the reverse order of the procedure used to place the wafer W on the mounting table 101. This completes the wafer processing.

[0056] Next, the plasma processing apparatus 1 is used to perform the plasma treatment of the wafer W placed on the wafer placement surface 103a. A method for detecting the state of the wafer W and the state of the edge ring E mounted on the ring mounting surface 103b will be described below. Note that each of the following steps is performed under the control of the controller M. The detection of the state of the wafer W and the state of the edge ring E is performed, for example, between successive plasma processing operations, that is, between the plasma processing of one wafer W and the plasma processing of another wafer W. Specifically, the detection of the state of the wafer W and the state of the edge ring E is performed each time the plasma processing of one wafer W is completed, or each time the plasma processing of a predetermined number of wafers W (for example, one lot) is completed.

[0057] When detecting the state of the wafer W and the state of the edge ring E, for example, after the plasma processing in the aforementioned wafer processing is completed, the lower shield 142 of the shield member 140 is raised to the transport position as shown in FIG. 2 before the wafer W is unloaded from the processing container 100.

[0058] Thereafter, the arm 170 is moved linearly toward the center of the mounting table 101 by the moving mechanism 180, and the first sensor 150 and the second sensor 160 are moved from the retraction region R2 to the processing region R1.

[0059] A first sensor 150 located within the processing region R1 detects the thickness of a native oxide film remaining on the surface of the wafer W as a state of the wafer W placed on the wafer placement surface 103a. A second sensor 160 located within the processing region R1 detects the distance to the edge ring E as a state of the edge ring E placed on the ring placement surface 103b. For example, the detection by the first sensor 150 and the detection by the second sensor 160 are performed simultaneously. By performing the detection simultaneously, the time required for the detection can be shortened.

[0060] Furthermore, the portion of the wafer W where detection is performed by the first sensor 150 is, for example, one location, but may be multiple locations along the direction of movement by the moving mechanism 180. Similarly, the portion of the edge ring E where detection is performed by the second sensor 160 is, for example, one location, but may be multiple locations along the direction of movement by the moving mechanism 180.

[0061] When the detection by the first sensor 150 and the second sensor 160 is completed, the wafer W on the mounting table 101 is transferred from the processing chamber 100 to a transfer chamber (not shown) via lift pins (not shown) or the like.

[0062] If the detection result of the state of the wafer W by the first sensor 150 is poor (specifically, for example, if the thickness of the native oxide film is equal to or greater than a predetermined value), a notification to that effect may be given, for example, via the display unit M1. Similarly, if the detection result of the state of the edge ring E by the second sensor 160 is poor (specifically, for example, if the distance to the edge ring E is equal to or greater than a predetermined value, i.e., if the amount of wear of the edge ring E is equal to or greater than a predetermined value), a notification to that effect may be given, for example, via the display unit M1. Furthermore, if the detection result of the state of the wafer W by the first sensor 150 or the detection result of the state of the edge ring E by the second sensor 160 is poor, the operation of the plasma processing apparatus 1 may be suspended.

[0063] <Modification> In the above example, the state of the wafer W placed on the wafer placement surface 103a is detected by the first sensor 150. However, instead, the state of the wafer placement surface 103a itself may be detected. The state of the wafer placement surface 103a may be, for example, the presence or absence of particles on the wafer placement surface 103a or the number of particles on the wafer placement surface 103a. Alternatively, the state of the wafer placement surface 103a may be the height of the above-mentioned convex portion 103c formed on the wafer placement surface 103a. In this case, the detection by the first sensor 150 is performed after the plasma-processed wafer W on the wafer mounting surface 103a is unloaded from the processing chamber 100. In this case, the detection by the first sensor 150 may be performed during maintenance, instead of between successive plasma processing operations.

[0064] Furthermore, the timing at which the detection is performed by the first sensor 150 may be different from the timing at which the detection is performed by the second sensor 160. For example, only the detection of the state of the edge ring E by the second sensor 160 may be performed during maintenance of the plasma processing apparatus 1.

[0065] In the above example, first arm 171 is fixed to second arm 172 and moves together with second arm 172. Alternatively, first arm 171 may be configured to be movable in the arm extension direction along second arm 172, independently of second arm 172. In this case, if there are multiple locations where detection is performed by first sensor 150 and second sensor 160, the measurement interval in distance can be made different between first sensor 150 and second sensor 160.

[0066] The mounting table 101 may be configured to be movable. Specifically, the mounting table 101 may be configured to be rotatable around a vertical axis passing through its center. In this case, the first sensor 150 and the second sensor may perform detection at multiple locations along the circumferential direction of the mounting table 101. In this case, the first sensor 150 and the second sensor 160 may perform detection while both the mounting table 101 and the first arm 171 and the second arm 172 are moving. This makes it possible to acquire the in-plane distribution of the state of the wafer W mounted on the wafer mounting surface 103a and the in-plane distribution of the state of the edge ring E mounted on the ring mounting surface 103b.

[0067] <Major Effects of This Embodiment> As described above, in this embodiment, the plasma processing apparatus 1 includes the first sensor 150 that detects the state of the wafer W placed on the wafer mounting surface 103a of the mounting table 101 or the state of the wafer mounting surface 103a, and the second sensor 160 that detects the state of the edge ring E placed on the ring mounting surface 103b of the mounting table 101. Therefore, it is possible to detect both the state of the wafer W placed on the wafer mounting surface 103a or the state of the wafer mounting surface 103a, and the state of the edge ring E placed on the ring mounting surface 103b of the mounting table 101.

[0068] The plasma processing apparatus 1 also includes an arm 170 that holds the first sensor 150 and the second sensor 160, and a moving mechanism 180 that moves the arm 170 to move the first sensor 150 and the second sensor 160 between a processing region R1 above the mounting table 101 in the processing vessel 100 and a retreat region R2 outside the processing region R1 in a top view in the processing vessel 100. That is, at least a part of the moving mechanism 180 is common to the first sensor 150 and the second sensor 160. Therefore, costs can be reduced compared to when separate moving mechanisms are provided for the first sensor 150 and the second sensor 160.

[0069] Furthermore, the above-described retreat area R2 is essential to prevent the first sensor 150 and the second sensor 160 from being damaged by plasma during plasma processing of the wafer W placed on the wafer placement surface 103a. However, if separate retreat areas are provided for the first sensor 150 and the second sensor 160, the processing vessel 100 and the plasma processing apparatus 1 will also become larger. Specifically, the occupied area (footprint) of the plasma processing apparatus 1 will become larger. In contrast, in this embodiment, the retreat area is shared by the first sensor 150 and the second sensor 160, so that the plasma processing apparatus 1 can be prevented from becoming larger.

[0070] Thus, according to this embodiment, it is possible to detect both the state of the wafer W placed on the wafer placement surface 103a of the placement table 101 or the state of the wafer placement surface 103a, and the state of the edge ring E placed on the placement table 101, while suppressing the increase in size and cost of the device.

[0071] As described above, an air cylinder may be used as the drive source of the movement mechanism 180. By using an air cylinder, costs can be reduced compared to when a motor is used.

[0072] <Other variations> FIG. 5 is a diagram illustrating another example of a movement mechanism that moves the arm 170 that holds the first sensor 150 and the second sensor 160. In FIG. The moving mechanism 180 shown in Fig. 1 etc. moves the arm 170 linearly. In contrast, the moving mechanism 180A in Fig. 5 rotates the arm 170 about a vertical axis. Specifically, the moving mechanism 180A rotates the arm 170 about the vertical axis, thereby moving the first sensor 150 and the second sensor 160 between the processing region R1 and the evacuation region R2.

[0073] The movement mechanism 180A has, for example, a base 181 that pivotally supports the base end of the arm 170 (specifically, the base end of the second arm 172). The movement mechanism 180A also has a drive source (not shown) that generates a drive force to rotate the arm 170. For example, a motor is used as the drive source.

[0074] Even when using the moving mechanism of this example, it is possible to detect both the state of the wafer W placed on the wafer placement surface 103a of the placement table 101 or the state of the wafer placement surface 103a, and the state of the edge ring E placed on the placement table 101, while suppressing the increase in size and cost of the device.

[0075] 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.

[0076] 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 are apparent to those skilled in the art from the description of this specification, in addition to or in place of the above-described effects.

[0077] Note that the following configuration examples also fall within the technical scope of the present disclosure. (1) A plasma processing apparatus for performing plasma processing on a substrate, a processing vessel that accommodates the substrate; a mounting table provided in the processing chamber, the mounting table having a substrate mounting surface on which the substrate is mounted and a ring mounting surface on which an edge ring is mounted so as to surround the substrate; a first sensor for detecting a state of the substrate placed on the substrate mounting surface of the mounting table or a state of the substrate mounting surface; a second sensor for detecting a state of the edge ring placed on the ring placement surface of the placement table; a holder provided in the processing vessel and holding the first sensor and the second sensor; a moving mechanism that moves the holding part to move the first sensor and the second sensor between a processing region above the mounting table and a retraction region common to the sensors, the retraction region being located outside the processing region in a top view within the processing vessel. (2) The plasma processing apparatus according to (1), wherein the movement mechanism moves the holder linearly between the processing region and the evacuation region. (3) The plasma processing apparatus according to (1), wherein the moving mechanism rotates the holding unit around a vertical axis between the processing region and the evacuation region. (4) The inside of the processing vessel is maintained at a vacuum during plasma processing; The inside of the holding portion is maintained at atmospheric pressure, the first sensor and the second sensor are provided inside the holding portion, the holding unit is provided with a window that transmits detection light in a portion corresponding to the first sensor and the second sensor, The plasma processing apparatus according to any one of (1) to (3), wherein a cable for transmitting signals between the first sensor and the second sensor and the outside of the processing vessel is arranged to pass through the inside of the holding part and reach the outside of the processing vessel. (5) The plasma processing apparatus according to any one of (1) to (4), wherein the first sensor detects a thickness of a film formed on the surface of the substrate placed on the substrate placement surface. (6) The plasma processing apparatus according to any one of (1) to (5), wherein the second sensor detects information relating to an amount of wear of the edge ring placed on the ring placement surface. (7) The plasma processing apparatus according to (6), wherein the information regarding the wear amount of the edge ring is a distance from the second sensor to the edge ring. (8) Further comprising a control unit, The plasma processing apparatus according to any one of (1) to (7), wherein the control unit performs control so that, between the plasma processing on one of the substrates and the plasma processing on another of the substrates, the first sensor detects the state of the substrate or the state of the substrate mounting surface, and the second sensor detects the state of the edge ring. (9) A detection method for detecting a state of a substrate on a substrate mounting surface of a mounting table provided in a processing chamber of a plasma processing apparatus or a state of the substrate mounting surface, and a state of an edge ring on a ring mounting surface of the mounting table, comprising: moving a holder that holds a first sensor that detects a state of the substrate on the substrate mounting surface or a state of the substrate mounting surface and a second sensor that detects a state of the edge ring on the ring mounting surface, and moving the first sensor and the second sensor from a retreat area that is located outside the processing area in a top view in the processing vessel and is common to all sensors, to a processing area above the mounting table in the processing vessel; performing detection using the first sensor and the second sensor located within the processing area. [Explanation of symbols]

[0078] 1. Plasma processing equipment 100 Processing container 101 Mounting table 103a Upper surface of the center of the electrostatic chuck 103b Upper surface of the peripheral edge of the electrostatic chuck 150 First Sensor 160 Second Sensor 170 Arm 180, 180A moving mechanism E Edge Ring R1 processing area R2 Evacuation area W wafer

Claims

1. A plasma processing apparatus for performing plasma processing on a substrate, a processing vessel that accommodates the substrate; a mounting table provided in the processing chamber, the mounting table having a substrate mounting surface on which the substrate is mounted and a ring mounting surface on which an edge ring is mounted so as to surround the substrate; a first sensor for detecting a state of the substrate placed on the substrate placement surface of the placement table or a state of the substrate placement surface; a second sensor for detecting a state of the edge ring placed on the ring placement surface of the placement table; a holder provided in the processing vessel and holding the first sensor and the second sensor; a moving mechanism that moves the holding part to move the first sensor and the second sensor between a processing region above the mounting table and a retraction region common to the sensors, the retraction region being located outside the processing region in a top view within the processing vessel.

2. The plasma processing apparatus according to claim 1 , wherein the movement mechanism moves the holder linearly between the processing region and the evacuation region.

3. The plasma processing apparatus according to claim 1 , wherein the moving mechanism rotates the holding unit about a vertical axis between the processing region and the evacuation region.

4. The inside of the processing vessel is maintained at a vacuum during plasma processing, The inside of the holding portion is maintained at atmospheric pressure, the first sensor and the second sensor are provided inside the holding portion, the holding portion is provided with a window that transmits detection light in a portion corresponding to the first sensor and the second sensor, 4. The plasma processing apparatus according to claim 1, wherein a cable for transmitting signals between the first sensor and the second sensor and the outside of the processing vessel is arranged to pass through the inside of the holding part and reach the outside of the processing vessel.

5. 4. The plasma processing apparatus according to claim 1, wherein the first sensor detects a thickness of a film formed on the surface of the substrate placed on the substrate placement surface.

6. 4. The plasma processing apparatus according to claim 1, wherein the second sensor detects information relating to an amount of wear of the edge ring placed on the ring placement surface.

7. The plasma processing apparatus of claim 6 , wherein the information relating to the amount of wear of the edge ring is a distance from the second sensor to the edge ring.

8. Further comprising a control unit, The plasma processing apparatus of any one of claims 1 to 3, wherein the control unit controls the first sensor to detect the state of the substrate or the state of the substrate support surface and the second sensor to detect the state of the edge ring between the plasma processing on one of the substrates and the plasma processing on another of the substrates.

9. 1. A detection method for detecting a state of a substrate on a substrate mounting surface of a mounting table provided in a processing chamber of a plasma processing apparatus, or a state of the substrate mounting surface, and a state of an edge ring on a ring mounting surface of the mounting table, comprising: moving a holder that holds a first sensor that detects a state of the substrate on the substrate mounting surface or a state of the substrate mounting surface and a second sensor that detects a state of the edge ring on the ring mounting surface, and moving the first sensor and the second sensor from a retreat area that is located outside the processing area in a top view in the processing vessel and is common to all sensors, to a processing area above the mounting table in the processing vessel; performing detection using the first sensor and the second sensor located within the processing area.

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