Substrate processing system and state acquisition method

Abstract

A substrate processing system according to an illustrative embodiment comprises a chamber which defines a space therein, a first support part which is disposed inside the chamber, and a measuring device which can be placed on the first support part. The measuring device includes a base substrate that is placed on the first support part and a triangulation sensor that is mounted on the base substrate. The triangulation sensor has a light source that emits light and an imaging element that images light emitted onto an object from the light source. The triangulation sensor measures, via triangulation, the distance to the object on the basis of an image captured by the imaging element.

Description

Substrate Processing System and State Acquisition Method

[0001] Exemplary embodiments of the present disclosure relate to a substrate processing system and a state acquisition method.

[0002] Patent Document 1 discloses a measuring instrument for acquiring capacitance. This measuring instrument inspects an edge ring by acquiring the capacitance generated between itself and the edge ring while being placed on an electrostatic chuck.

[0003] Patent Document 2 discloses a substrate processing system including an imaging device. In this system, the state of an internal object is acquired by imaging the inside of the substrate processing device with the imaging device provided in the transfer mechanism.

[0004] Japanese Unexamined Patent Application Publication No. 2017 - 5133, Japanese Unexamined Patent Application Publication No. 2022 - 42122

[0005] The present disclosure provides a technique for acquiring the state of a substrate processing system.

[0006] In one exemplary embodiment, a substrate processing system is provided. The substrate processing system includes a chamber that defines a space inside, a first support portion disposed inside the chamber, and a measuring device that can be placed on the first support portion. The measuring device includes a base substrate placed on the first support portion and a triangulation sensor mounted on the base substrate. The triangulation sensor has a light source that irradiates light and an image sensor that captures the light irradiated from the light source onto an object. The triangulation sensor measures the distance to the object by triangulation based on the image captured by the image sensor.

[0007] According to one exemplary embodiment, a technique for acquiring the state of a substrate processing system is provided.

[0008] This is a diagram illustrating a processing system. This is a perspective view illustrating an aligner. This is a diagram showing an example of a plasma processing apparatus. This is a perspective view showing an example of a measuring device from above. This is a block diagram showing an example of the electrical system of a measuring device. This is a schematic diagram illustrating the measurement principle of an example of a measuring device. This is a schematic diagram illustrating the measurement principle of an example of a measuring device. This is a graph showing an example of the relationship between coordinates and distance used in a measuring device. This is a flowchart showing an example of a state acquisition method. This is a perspective view showing another example of a measuring device from above. This is a schematic diagram illustrating the measurement principle of another example of a measuring device. This is a diagram schematically showing a cross-section of an example of an edge ring. This is a diagram showing the profile of a worn edge ring.

[0009] Various exemplary embodiments will be described below.

[0010] In one exemplary embodiment, a substrate processing system is provided. The substrate processing system comprises a chamber defining an internal space, a first support unit disposed within the chamber, and a measuring device mountable on the first support unit. The measuring device includes a base substrate mounted on the first support unit and a triangulation sensor mounted on the base substrate. The triangulation sensor has a light source that emits light and an image sensor that captures the light emitted from the light source onto an object. The triangulation sensor measures the distance to the object by triangulation based on the image captured by the image sensor.

[0011] In one exemplary embodiment, a method for acquiring the state of a substrate processing system is provided. The substrate processing system comprises a chamber defining an internal space, a first support unit disposed within the chamber, and a measuring device mountable on the first support unit. The measuring device includes a base substrate mounted on the first support unit and a triangulation sensor mounted on the base substrate. The triangulation sensor includes a light source that emits light and an image sensor that images the light emitted from the light source onto an object. The method includes the step of placing the measuring device on the first support unit. The method includes the step of imaging the light with the image sensor while the object is illuminated from the light source of the measuring device mounted on the first support unit. The method includes the step of measuring the distance between the measuring device and the object based on triangulation, referring to the image captured by the image sensor. The method includes the step of acquiring the state of the substrate processing system based on the distance between the measuring device and the object.

[0012] In the above-described substrate processing system and state acquisition method, the distance between the measuring device and the object is measured by a triangulation sensor provided on the measuring device, which is placed on the first support and is stationary. Therefore, it is less susceptible to the influence of the environment inside the chamber and is also less susceptible to the influence of vibrations in the substrate processing system, so that the state of the substrate processing system can be acquired accurately and stably. In one exemplary embodiment, the position of the measuring device can be acquired as the state of the substrate processing system by measuring the distance between the measuring device and the object. In another exemplary embodiment, the degree of wear of the object can be acquired as the state of the substrate processing system by measuring the distance between the measuring device and the object.

[0013] A substrate processing system in one exemplary embodiment may further include a control device that compares the distance to an object measured by a triangulation sensor with a pre-stored reference value of the distance from the triangulation sensor to the object.

[0014] In one exemplary embodiment, the triangulation sensors may be provided at three or more locations on the base substrate that are spaced apart from each other.

[0015] In one exemplary embodiment, the measuring device may have an optical component that shapes the light emitted from a light source into a linear form.

[0016] In one exemplary embodiment, a triangulation sensor can measure the distance to an object based on the position of light in an image captured by an image sensor.

[0017] A substrate processing system in one exemplary embodiment may further include a second support portion surrounding a first support portion within a chamber, and a ring member placed on the second support portion.

[0018] In one exemplary embodiment, the object may be a ring member. The triangulation sensor can illuminate the inner surface of the ring member with light from a light source.

[0019] In one exemplary embodiment, the object may be a ring member. The triangulation sensor may have an optical path changing member that controls the optical path of the light source so that light strikes the upper surface of the ring member.

[0020] In one exemplary embodiment, the object may be a consumable component. The triangulation sensor can calculate the amount of consumable component worn based on the distance to the object.

[0021] Various embodiments will be described in detail below with reference to the drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals.

[0022] A substrate processing system in one exemplary embodiment comprises a processing system and a measuring device. First, the processing system will be described. Figure 1 is a diagram illustrating the processing system. The processing system 1 comprises stages 2a to 2d, containers 4a to 4d, a loader module LM, an aligner AN, load lock modules LL1 and LL2, process modules PM1 to PM6, a transfer module TF, and a control unit MC. The number of stages 2a to 2d, the number of containers 4a to 4d, the number of load lock modules LL1 and LL2, and the number of process modules PM1 to PM6 are not limited to one or more arbitrary numbers.

[0023] The bases 2a to 2d are arranged along one edge of the loader module LM. The containers 4a to 4d are each mounted on the bases 2a to 2d. Each of the containers 4a to 4d is, for example, a container called a FOUP (Front Opening Unified Pod). Each of the containers 4a to 4d may be configured to contain a workpiece W. The workpiece W has a substantially disc shape, such as a wafer.

[0024] The loader module LM has a chamber wall that defines a transport space under atmospheric pressure within it. A transport device TU1 is provided within this transport space. The transport device TU1 is, for example, an articulated robot and is controlled by the control unit MC. The transport device TU1 is configured to transport the workpiece W between containers 4a to 4d and the aligner AN, between the aligner AN and the load lock modules LL1 to LL2, and between the load lock modules LL1 to LL2 and the containers 4a to 4d.

[0025] The aligner AN is connected to the loader module LM. The aligner AN is configured to adjust (calibrate) the position of the workpiece W. Figure 2 is a perspective view illustrating the aligner. The aligner AN has a support base 6T, a drive unit 6D, and a sensor 6S. The support base 6T is a rotatable base with a vertically extending axis as its center, and is configured to support the workpiece W on it. The support base 6T is rotated by the drive unit 6D. The drive unit 6D is controlled by the control unit MC. When the support base 6T rotates due to the power from the drive unit 6D, the workpiece W placed on the support base 6T also rotates.

[0026] Sensor 6S is an optical sensor that detects the edges of the workpiece W while the workpiece W is rotating. From the edge detection results, Sensor 6S detects the amount of deviation of the angular position of the notch WN (or another marker) on the workpiece W relative to the reference angular position, and the amount of deviation of the center position of the workpiece W relative to the reference position. Sensor 6S outputs the amount of deviation of the angular position of the notch WN and the amount of deviation of the center position of the workpiece W to the control unit MC. Based on the amount of deviation of the angular position of the notch WN, the control unit MC calculates the amount of rotation of the support base 6T to correct the angular position of the notch WN to the reference angular position. The control unit MC controls the drive unit 6D to rotate the support base 6T by this amount of rotation. This corrects the angular position of the notch WN to the reference angular position. Furthermore, the control unit MC controls the position of the end effector of the transport device TU1 when receiving the workpiece W from the aligner AN, based on the amount of displacement of the center position of the workpiece W. As a result, the center position of the workpiece W coincides with a predetermined position on the end effector of the transport device TU1.

[0027] Returning to Figure 1, load lock module LL1 and load lock module LL2 are each located between loader module LM and transfer module TF. Load lock module LL1 and load lock module LL2 each provide a pre-pressure chamber.

[0028] The transfer module TF is hermetically connected to the load lock modules LL1 and LL2 via gate valves. The transfer module TF provides a depressurized chamber. A conveying device TU2 is provided in this depressurized chamber. The conveying device TU2 is, for example, an articulated robot having a conveying arm TUa and is controlled by a control unit MC. The tip of the conveying arm TUa is provided with a conveying fork 9 (end effector) for holding the workpiece W. The conveying device TU2 is configured to convey the workpiece W between the load lock modules LL1 to LL2 and the process modules PM1 to PM6, and between any two process modules among the process modules PM1 to PM6.

[0029] Process modules PM1 to PM6 are hermetically connected to the transfer module TF via gate valves. Each of the process modules PM1 to PM6 is a processing unit configured to perform a specific treatment, such as plasma treatment, on the workpiece W.

[0030] The following is an example of the sequence of operations when processing the workpiece W in this processing system 1. The transport device TU1 of the loader module LM takes the workpiece W from one of the containers 4a to 4d and transports the workpiece W to the aligner AN. Next, the transport device TU1 takes the workpiece W, whose position has been adjusted, from the aligner AN and transports the workpiece W to one of the load lock modules LL1 and LL2. Next, the load lock module reduces the pressure in the pre-pressure chamber to a predetermined pressure. Next, the transport device TU2 of the transfer module TF takes the workpiece W from the load lock module and transports the workpiece W to one of the process modules PM1 to PM6. Then, one or more of the process modules PM1 to PM6 process the workpiece W. Then, the conveying device TU2 conveys the processed workpiece W from the process module to one of the load lock modules LL1 and LL2. Next, the conveying device TU1 conveys the workpiece W from one of the load lock modules to one of the containers 4a to 4d.

[0031] As described above, this processing system 1 includes a control unit MC. The control unit MC may be a computer equipped with a processor, memory and other storage devices, a display device, input / output devices, communication devices, etc. The series of operations of the processing system 1 described above are realized by the control unit MC controlling each part of the processing system 1 according to a program stored in the storage device.

[0032] Figure 3 shows an example of a plasma processing apparatus that can be adopted as one of the process modules PM1 to PM6. The plasma processing apparatus 10 shown in Figure 3 is a capacitively coupled plasma etching apparatus. The plasma processing apparatus 10 comprises a substantially cylindrical chamber body 12. The chamber body 12 is formed from, for example, aluminum, and its inner wall surface may be subjected to anodizing treatment. This chamber body 12 is grounded for safety.

[0033] A substantially cylindrical support portion 14 is provided on the bottom of the chamber body 12. The support portion 14 is made of, for example, an insulating material. The support portion 14 is located inside the chamber body 12 and extends upward from the bottom of the chamber body 12. A stage ST is provided inside the chamber S provided by the chamber body 12. The stage ST is supported by the support portion 14.

[0034] The stage ST has a lower electrode LE and an electrostatic chuck ESC. The lower electrode LE includes a first plate 18a and a second plate 18b. The first plate 18a and the second plate 18b are made of a metal such as aluminum and are substantially disc-shaped. The second plate 18b is provided on the first plate 18a and is electrically connected to the first plate 18a.

[0035] An electrostatic chuck ESC is provided on the second plate 18b. The electrostatic chuck ESC has a structure in which electrodes, which are conductive films, are arranged between a pair of insulating layers or insulating sheets, and has a substantially disc shape. A DC power supply 22 is electrically connected to the electrodes of the electrostatic chuck ESC via a switch 23. This electrostatic chuck ESC attracts the workpiece W by electrostatic force such as Coulomb force generated by the DC voltage from the DC power supply 22. In this way, the electrostatic chuck ESC can hold the workpiece W.

[0036] The peripheral edge of the second plate 18b is ring-shaped so as to surround the electrostatic chuck ESC. An edge ring ER is provided on the peripheral edge of the second plate 18b. This edge ring ER is provided so as to surround the edge of the workpiece W and the electrostatic chuck ESC. The edge ring ER has a first portion P1 and a second portion P2 (see Figures 4 and 12). The first portion P1 and the second portion P2 have an annular plate shape. The second portion P2 is the outer portion of the first portion P1. The second portion P2 has a greater thickness in the height direction than the first portion P1. The inner circumferential surface P2i of the second portion P2 has a larger diameter than the inner circumferential surface P1i of the first portion P1. The workpiece W is placed on the electrostatic chuck ESC such that its edge region is located above the first portion P1 of the edge ring ER. The edge ring ER can be formed from any of the following materials: silicon, silicon carbide, silicon oxide, etc.

[0037] A refrigerant flow path 24 is provided inside the second plate 18b. The refrigerant flow path 24 constitutes a temperature control mechanism. Refrigerant is supplied to the refrigerant flow path 24 from a chiller unit located outside the chamber body 12 via piping 26a. The refrigerant supplied to the refrigerant flow path 24 is returned to the chiller unit via piping 26b. In this way, refrigerant circulates between the refrigerant flow path 24 and the chiller unit. By controlling the temperature of this refrigerant, the temperature of the workpiece W supported by the electrostatic chuck ESC is controlled.

[0038] The stage ST has multiple (for example, three) through holes 25 that penetrate the stage ST. The multiple through holes 25 are formed on the inside of the electrostatic chuck ESC in a plan view. A lift pin 25a is inserted into each of these through holes 25. In Figure 3, one through hole 25 with one lift pin 25a inserted is depicted. The lift pin 25a is provided to be able to move up and down within the through hole 25. When the lift pin 25a rises, the workpiece W supported on the electrostatic chuck ESC rises.

[0039] The stage ST has multiple (for example, three) through-holes 27 that penetrate the stage ST (lower electrode LE) at a position outside the electrostatic chuck ESC in a plan view. A lift pin 27a is inserted into each of these through-holes 27. In Figure 3, one through-hole 27 with one lift pin 27a inserted is depicted. The lift pin 27a is provided to be vertically movable within the through-hole 27. The rise of the lift pin 27a causes the edge ring ER, which is supported on the second plate 18b, to rise.

[0040] Furthermore, the plasma processing apparatus 10 is provided with a gas supply line 28. The gas supply line 28 supplies heat transfer gas, such as He gas, from the heat transfer gas supply mechanism between the upper surface of the electrostatic chuck ESC and the back surface of the workpiece W.

[0041] The plasma processing apparatus 10 also includes an upper electrode 30. The upper electrode 30 is positioned above the stage ST and opposite to the stage ST. The upper electrode 30 is supported on the upper part of the chamber body 12 via an insulating shielding member 32. The upper electrode 30 may include a top plate 34 and a support 36. The top plate 34 faces the chamber S and is provided with a plurality of gas discharge holes 34a. The top plate 34 may be formed from silicon or quartz. Alternatively, the top plate 34 may be constructed by forming a plasma-resistant film, such as yttrium oxide, on the surface of an aluminum base material.

[0042] The support 36 detachably supports the top plate 34 and may be made of a conductive material such as aluminum. The support 36 may have a water-cooling structure. A gas diffusion chamber 36a is provided inside the support 36. Multiple gas passage holes 36b that communicate with the gas discharge hole 34a extend downward from this gas diffusion chamber 36a. The support 36 also has a gas inlet 36c that guides the processed gas into the gas diffusion chamber 36a, and a gas supply pipe 38 is connected to this gas inlet 36c.

[0043] A gas source group 40 is connected to a gas supply pipe 38 via a valve group 42 and a flow controller group 44. The gas source group 40 includes a plurality of gas sources for a plurality of types of gases. The valve group 42 includes a plurality of valves, and the flow controller group 44 includes a plurality of flow controllers such as mass flow controllers. The plurality of gas sources of the gas source group 40 are each connected to the gas supply pipe 38 via the corresponding valve of the valve group 42 and the corresponding flow controller of the flow controller group 44.

[0044] In the plasma processing apparatus 10, a deposition shield 46 is detachably provided along the inner wall of the chamber main body 12. The deposition shield 46 is also provided on the outer periphery of the support portion 14. The deposition shield 46 prevents etching by-products (deposits) from adhering to the chamber main body 12 and can be configured by coating an aluminum material with a ceramic such as yttrium oxide.

[0045] An exhaust plate 48 is provided between the bottom side of the chamber main body 12 and between the support portion 14 and the side wall of the chamber main body 12. The exhaust plate 48 can be configured, for example, by coating an aluminum material with a ceramic such as yttrium oxide. A plurality of holes penetrating in the plate thickness direction are formed in the exhaust plate 48. Below the exhaust plate 48 and in the chamber main body 12, an exhaust port 12e is provided. An exhaust device 50 is connected to the exhaust port 12e via an exhaust pipe 52. The exhaust device 50 has a vacuum pump such as a pressure regulating valve and a turbo molecular pump, and can reduce the pressure in the space in the chamber main body 12 to a desired degree of vacuum. Further, a carry-in / outlet 12g for the workpiece W is provided on the side wall of the chamber main body 12, and this carry-in / outlet 12g can be opened and closed by a gate valve 54.

[0046] Further, the plasma processing apparatus 10 further includes a first high-frequency power supply 62 and a second high-frequency power supply 64. The first high-frequency power supply 62 is a power supply that generates a first high-frequency for plasma generation, and for example, generates a high-frequency having a frequency of 27 to 100 MHz. The first high-frequency power supply 62 is connected to the upper electrode 30 via a matching unit 66. The matching unit 66 has a circuit for matching the output impedance of the first high-frequency power supply 62 and the input impedance on the load side (upper electrode 30 side). Note that the first high-frequency power supply 62 may be connected to the lower electrode LE via the matching unit 66.

[0047] The second high-frequency power supply 64 is a power supply that generates a second high-frequency for attracting ions to the workpiece W, and for example, generates a high-frequency having a frequency within the range of 400 kHz to 13.56 MHz. The second high-frequency power supply 64 is connected to the lower electrode LE via a matching unit 68. The matching unit 68 has a circuit for matching the output impedance of the second high-frequency power supply 64 and the input impedance on the load side (lower electrode LE side).

[0048] In this plasma processing apparatus 10, gas from one or more selected gas sources among a plurality of gas sources is supplied to the chamber S. Further, the pressure of the chamber S is set to a predetermined pressure by the exhaust device 50. Furthermore, the gas in the chamber S is excited by the first high-frequency from the first high-frequency power supply 62. Thereby, plasma is generated. Then, the workpiece W is processed by the generated active species. Note that, if necessary, ions may be attracted to the workpiece W by the bias based on the second high-frequency of the second high-frequency power supply 64.

[0049] Hereinafter, the measuring device will be described. FIG. 4 is a schematic perspective view showing the measuring device as viewed from the upper surface side. In FIG. 4, a part of the edge ring ER is drawn together with the measuring device 100. FIG. 5 is a block diagram of the electrical system of the measuring device (triangulation sensor). In one exemplary embodiment, the distance between the measuring device 100 transported on the electrostatic chuck ESC and the inner peripheral surface of the edge ring ER as an object can be measured, and the transport position of the measuring device 100 and the like can be derived. This will be described in detail below.

[0050] The measuring device 100 shown in Figures 4 and 5 includes a base substrate 102. The base substrate 102 is formed from, for example, silicon and has a shape similar to that of the workpiece W, i.e., a roughly disc shape. The diameter of the base substrate 102 is the same as the diameter of the workpiece W, for example, 300 mm. In addition, a notch 102N (or another marker) detectable by the sensor 6S of the aligner AN is formed on the edge of the base substrate 102. Therefore, when the measuring device 100 is transported, the rotational position of the measuring device 100 can be controlled in the same way as the workpiece W.

[0051] The measuring device 100 includes a triangulation sensor 101 mounted on a base substrate 102. The triangulation sensor 101 includes an optical module 110 and a control device 120. Although only one optical module 110 is shown in Figure 4, the measuring device 100 according to one exemplary embodiment may include multiple optical modules 110 on a single base substrate 102. For example, if the measuring device 100 has three optical modules 110, the optical modules 110 may be provided at three locations on the base substrate 102 that are spaced apart from each other.

[0052] The optical module 110 includes a light source that irradiates light onto an object and an optical sensor that detects the light irradiated onto the object from the light source. An exemplary embodiment of the optical module 110 includes a light source 111, a first mirror 112, a first lens 113, a slit member 115, a second lens 116, a second mirror 117, and an image sensor 118.

[0053] The light source 111 is fixed to the upper surface of the base substrate 102. One example of a light source 111 is an LED (light-emitting diode) light source. For example, the light source 111 irradiates light upwards onto the base substrate 102. The first mirror 112 changes the optical path of the light by reflecting the light output from the light source 111. That is, the first mirror 112 is fixed to the upper surface of the base substrate 102 so as to cover at least a portion above the light source 111 and is positioned in the optical path of the light source 111. In one exemplary embodiment, the light output from the light source 111 is reflected by the first mirror 112 and irradiated along the upper surface of the base substrate 102 toward the outside of the base substrate 102.

[0054] The first lens 113 is fixed on the base substrate 102 so that light reflected by the first mirror 112 is input (incident) to it. The first lens 113 is positioned between the first mirror 112 and the slit member 115 in the optical path of the light source 111. The first lens 113 can convert the light input from the light source 111 into parallel light.

[0055] The slit member 115 (optical component) allows a portion of the light input from the first lens 113 to pass through. The slit member 115 has a slit that extends in the vertical direction. The light input from the first lens 113 is converted into line-shaped light by passing through the slit. That is, the light that has passed through the slit has a straight line (line segment) of a predetermined length in the vertical direction perpendicular to the optical axis.

[0056] The image sensor 118 is fixed to the upper surface of the base substrate 102 and captures light irradiated onto an object from the light source 111. For example, the image sensor 118 may be an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor) or a CCD (Charge Coupled Device). In the illustrated example, the image sensor 118 is fixed to the base substrate 102 such that the incident surface into which light is incident faces upward.

[0057] The second mirror 117 is fixed to the upper surface of the base substrate 102 so as to cover at least a portion above the image sensor 118 and is positioned in the optical path of the image sensor 118. In one exemplary embodiment, the optical axis of the image sensor 118 is altered by the second mirror 117 so as to be directed outward along the upper surface of the base substrate 102.

[0058] The second lens 116 is fixed on the base substrate 102 so that light from the light source 111 irradiating the object is input to it. The second lens 116 is positioned on the optical axis of the image sensor 118 so that the light irradiating the object forms an image on the image sensor 118.

[0059] The optical axis from the light source 111 (first mirror 112) to the object and the optical axis from the object to the image sensor 118 (second mirror 117) intersect with each other. That is, the light output from the light source 111 is reflected by the first mirror 112, input to the slit member 115 via the first lens 113, and irradiates the object. The light irradiated onto the object is then input to the second mirror 117 via the second lens 116, reflected by the second mirror 117, and input to the image sensor 118.

[0060] The control device 120 controls the operation of the optical module 110 and calculates the distance to an object using triangulation based on the image data detected by the optical module 110. For example, the control device 120 includes an arithmetic unit 121, a storage device 122, a battery 123, and a communication unit 125. The arithmetic unit 121 includes, for example, a CPU and implements various functions by executing programs. The storage device 122 stores programs executed by the CPU and other data necessary for calculating distance using triangulation. The storage device 122 also stores calculation results and other data. The battery 123 supplies power to the optical module 110 as well as to each circuit constituting the control device 120. The communication unit 125 communicates with other external devices. The communication unit 125 may be, for example, a wireless communication module.

[0061] In one exemplary embodiment, the control device 120 measures the distance to an object based on the position of light in the image. The principle of distance measurement in an example triangulation sensor 101 will be described below. Figures 6 and 7 are schematic diagrams illustrating the measurement principle of the triangulation sensor 101. The light source 111, slit member 115, and imaging device 119 shown in Figure 6 are simplified representations of the triangulation sensor 101. The imaging device 119 includes at least an image sensor and an imaging optical system. An example imaging device 119 may include the image sensor 118, second mirror 117, and second lens 116 shown in Figure 4. Figure 6 shows the state in which light output from the light source 111 and formed into a line by the slit member 115 is irradiated onto the object 99. The imaging device 119 images the object 99 so as to include the position where the light from the light source 111 is irradiating it. In Figure 6, the object 99a located near the triangulation sensor 101 is shown by a solid line, and the object 99b located far from the triangulation sensor 101 is shown by a dashed line. Additionally, the light 112a irradiated onto object 99a is shown by a solid line, and the light 112b irradiated onto object 99b is shown by a dashed line.

[0062] Figure 7 schematically shows an image 150 in which an image of object 99a when it is located close to the triangulation sensor 101 and an image of object 99b when it is located far from the triangulation sensor 101 are superimposed. In Figure 7, the captured slit-shaped light is shown within the imaging range of the image sensor 118. In image 150, as in Figure 6, the image 112a1 of light illuminating object 99a located close to the triangulation sensor 101 is shown by a solid line, and the image 112b1 of light illuminating object 99b located far from the triangulation sensor 101 is shown by a dashed line.

[0063] In one exemplary embodiment, data of the luminance waveform of light irradiated onto the object 99 is extracted from the image 150. For example, the control device 120 sequentially extracts luminance data from pixels at predetermined positions in the vertical direction of the image 150 along the horizontal direction. In the illustrated example, the luminance of the pixel at the center position in the vertical direction is extracted along the horizontal direction. That is, the luminance at the position of the dashed line in the image 150 is extracted.

[0064] The luminance waveform can be shown as a graph with the horizontal axis representing the coordinates (horizontal position) of the pixels within the image 150 and the vertical axis representing the luminance of the corresponding pixels. In Figure 7, the luminance waveform 112a2 of light illuminating an object 99a at a close position is shown as a solid line, and the luminance waveform 112b2 of light illuminating an object 99b at a distant position is shown as a dashed line. As shown in the figure, there is a difference in the peak position of the luminance waveform when the object 99 is close to the triangulation sensor 101 and when it is far away. Therefore, by detecting the waveform peak of the luminance waveform, the distance to the object 99 can be derived based on the coordinates of the waveform peak.

[0065] In one exemplary embodiment, distance is derived from coordinates based on a pre-acquired relationship between coordinates and distance. Figure 8 is a graph showing the pre-acquired relationship between coordinates and distance. In the graph of Figure 8, the vertical axis represents the distance when the distance between the triangulation sensor 101 and the object is changed, and the horizontal axis represents the peak coordinates of the light in the image captured at each distance. For example, x1 is the horizontal coordinate of the light in the image captured when the distance from the triangulation sensor 101 to the object is y1. In one example, distance can be derived from the coordinates of the light in the image by using a function f(x) that approximates multiple measurement results acquired by changing the distance. The function f(x) that shows the relationship between distance y and coordinate x is stored in the storage device 122 of the control device 120. In this case, the control device 120 can calculate the distance by substituting the coordinates of the acquired waveform peaks into the function f(x).

[0066] In one exemplary embodiment, light output from the light source 111 is irradiated onto the inner circumferential surface P2i of the edge ring ER, and an image of the edge ring ER, including the irradiation position, is captured by the image sensor 118. This allows the control device 120 to derive the distance between the triangulation sensor 101 and the edge ring ER. In one example, the distance to the edge ring ER measured by the triangulation sensor 101 is compared with a pre-stored reference value for the distance from the triangulation sensor 101 to the edge ring ER. This allows the amount of deviation between the center position of the edge ring ER and the center position of the measuring device 100 to be calculated. The reference value for the distance from the triangulation sensor 101 to the edge ring ER may be the distance when the center of the edge ring ER coincides with the center of the base substrate 102.

[0067] The following describes a measurement method (state acquisition method) using the measuring device 100. Figure 9 shows a series of steps in a measurement method according to one exemplary embodiment. In semiconductor manufacturing equipment such as processing system 1, the edge ring ER wears out with use and requires periodic replacement. When replacing the edge ring ER, it is important to position the workpiece W and the edge ring ER in an optimal positional relationship in order to stabilize productivity. When checking the positional relationship between the workpiece W and the edge ring ER, it is generally necessary to open the chamber. Therefore, the checking work can become complicated. Thus, it is desirable to check the positional relationship accurately using a simple method.

[0068] As described above, the transport device TU2 in the processing system 1 is controlled by the control unit MC. In one exemplary embodiment, the transport device TU2 can transport the edge ring ER onto the second plate 18b based on transport position data transmitted from the control unit MC. The transport device TU2 can also transport the workpiece W and the measuring device 100 onto the electrostatic chuck ESC based on transport position data transmitted from the control unit MC.

[0069] In one example, any of process modules PM1 to PM6 may be used as a storage location for the edge ring ER. As described above, process modules PM1 to PM6 are hermetically connected to the transfer module TF via a gate valve. In this case, the edge ring ER can be replaced by the transport device TU2 without exposing the process module to the atmosphere. Note that the following measurement method assumes that the process module is not exposed to the atmosphere.

[0070] The measurement method shown in Figure 9 measures the transport position of the measuring device 100 while the edge ring ER is placed on the second plate 18b. First, step ST1 is performed. In step ST1, the measuring device 100 is transported onto the electrostatic chuck ESC, which is the area surrounded by the edge ring ER. Specifically, the transport device TU1 transports the measuring device 100 from one of the containers 4a to 4d to one of the load lock modules LL1 and LL2. Then, the transport device TU2 transports the measuring device 100 from one of the load lock modules to the process module based on the transport position data, and places the measuring device 100 on the electrostatic chuck ESC. The transport position data is, for example, coordinate data predetermined so that the center position of the measuring device 100 coincides with the center position of the electrostatic chuck ESC.

[0071] In the following step ST2, imaging is performed by the optical module 110 of the measuring device 100, which is placed on the electrostatic chuck ESC. That is, when the measuring device 100 is transported onto the electrostatic chuck ESC, light is irradiated from the light source 111 under the control of the control device 120, and imaging is performed by the image sensor 118 while the light is irradiated. The control device 120 may control the light source 111 and the image sensor 118 so that imaging is performed when predetermined conditions are met. For example, the control device 120 may control the operation of the light source 111 and the image sensor 118 using a timer or the like so that imaging starts when the measuring device 100 is transported onto the electrostatic chuck ESC by the transport device TU2.

[0072] In the following step ST3, the luminance waveform is extracted. That is, the control device 120 acquires the image captured by the image sensor 118 in step ST2 and extracts the luminance waveform from the acquired image. The control device 120 detects the coordinate with the highest luminance among the extracted luminance waveforms as the waveform peak (step ST4).

[0073] In the subsequent step ST5, the control device 120 calculates position information corresponding to the transport position of the measuring device 100. This position information is recorded in the storage device 122. The position information may be the amount of deviation between the center position of the edge ring ER and the center position of the measuring device 100. In one exemplary embodiment, the measuring device 100 has a plurality of optical modules 110 evenly arranged in the circumferential direction of the base substrate 102. In this case, the amount of deviation between the center position of the edge ring ER and the center position of the measuring device 100 can be calculated based on the distances between the inner circumferential surface P2i of the edge ring ER and the optical modules 110 in different radial directions of the base substrate 102.

[0074] In the following step ST6, the measuring device 100 is removed from the process module and returned to one of the transfer module TF, load lock modules LL1, LL2, loader module LM, or containers 4a to 4d.

[0075] In the subsequent step ST7, position information indicating the transport position of the measuring device 100 is transmitted to the control unit MC, for example, by a communication device. The control unit MC may determine whether the amount of deviation between the center position of the edge ring ER and the center position of the measuring device 100 exceeds a predetermined threshold. If it is determined that the amount of deviation is less than or equal to the predetermined threshold, it is confirmed that the measuring device 100 has been transported accurately. On the other hand, if it is determined that the amount of deviation is greater than the threshold, the transport position by the transport device is adjusted. That is, the transport position data is adjusted to cancel out the amount of deviation.

[0076] As described above, in one exemplary embodiment, a substrate processing system 1S is provided. The substrate processing system 1S comprises a chamber S that defines a space inside, an electrostatic chuck ESC (first support part) disposed within the chamber S, and a measuring device 100 that can be mounted on the electrostatic chuck ESC. The measuring device 100 includes a base substrate 102 that is placed on the electrostatic chuck ESC, and a triangulation sensor 101 mounted on the base substrate 102. The triangulation sensor 101 has a light source 111 that emits light, and an image sensor 118 that detects the light emitted from the light source 111 onto the object. The triangulation sensor 101 measures the distance to the object by triangulation based on image data captured by the image sensor 118.

[0077] Furthermore, in one exemplary embodiment, a method for acquiring the state of a substrate processing system 1S is provided. This method includes the step of placing a measuring device 100 on an electrostatic chuck ESC. This method includes the step of detecting light with an image sensor 118 while light is irradiated onto an object (for example, an edge ring ER) from the light source 111 of the measuring device 100 placed on the electrostatic chuck ESC. This method includes the step of measuring the distance between the measuring device 100 and the object based on triangulation by referring to the image detected by the image sensor 118. This method includes the step of acquiring the state of the substrate processing system 1S based on the distance between the measuring device 100 and the object.

[0078] For example, when acquiring the status of a substrate processing system using a capacitive sensor, the sensor is susceptible to environmental factors such as temperature and humidity within the chamber. Also, when acquiring the status of a substrate processing system using an imaging device installed on a transport device, the imaging device may be affected by vibrations of the transport device.

[0079] In the above-described substrate processing system and state acquisition method, the distance between the measuring device 100 and the object is measured by a triangulation sensor 101 provided on the measuring device 100, which is placed on an electrostatic chuck ESC and is stationary. Therefore, it is less susceptible to the influence of the environment inside the chamber and is also less susceptible to the influence of vibrations in the substrate processing system, so the state of the substrate processing system can be acquired accurately and stably. In one exemplary embodiment, the position of the measuring device 100 can be acquired as the state of the substrate processing system by measuring the distance between the measuring device 100 and the object.

[0080] In one exemplary embodiment, the substrate processing system may have a control device 120 that compares the distance to an object measured by a triangulation sensor 101 with a pre-stored reference value of the distance from the triangulation sensor 101 to the object. In this case, the amount of deviation between the measured distance and the reference value can be obtained. For example, the state of the substrate processing system may be determined based on the magnitude of the deviation.

[0081] In one exemplary embodiment, the triangulation sensors 101 may be provided at three or more spaced locations on the base substrate 102. In this case, each triangulation sensor 101 can illuminate a different location on the object. That is, the distance between each of the three or more different locations on the object and the triangulation sensor 101 can be measured. In this case, it is easier to understand the relative positional relationship between the object and the measuring device.

[0082] In one exemplary embodiment, the measuring device 100 may have a slit member 115 (optical component) that directs the light emitted from the light source 111 into a line. In this case, since the measurement is performed based on an image captured of the slit light, it is less susceptible to the effects of surface roughness due to wear and tear on the object. By focusing the light emitted from the light source 111 in at least one direction, the measurement accuracy can be improved. In the above example, the light source 111 is shown as an LED, but the type of light source is not particularly limited. For example, a laser light source may be used. In this case, the measuring device does not need to have a slit member.

[0083] In one exemplary embodiment, the triangulation sensor 101 can measure the distance to an object based on the position of light in the image captured by the image sensor 118. In this configuration, for example, a function representing the relationship between the position of light in the image and the distance to the object, a lookup table, or the like may be used.

[0084] In one exemplary embodiment, the substrate processing system may include a second plate 18b (second support portion) surrounding the electrostatic chuck ESC within the chamber, and an edge ring ER placed on the second plate 18b. In this case, the triangulation sensor 101 can irradiate the inner surface of the edge ring ER with light from the light source 111. With such a configuration, the amount of displacement between the center of the edge ring ER and the center of the measuring device 100 can be easily obtained.

[0085] Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments.

[0086] Figure 10 is a perspective view showing a measuring device according to another exemplary embodiment. The measuring device 200 shown in Figure 10 has an optical path changing member that changes (controls) the optical path of the light source 111 so that light strikes the upper surface of the edge ring ER. With this measuring device 200, the degree of wear of the edge ring ER can be obtained by calculating the height position of the upper surface of the edge ring ER.

[0087] The measuring device 200 will now be described. Detailed explanations of components common to the measuring device 100 will be omitted. The measuring device 200 includes a base board 102. A triangulation sensor 201 is mounted on the base board 102. The triangulation sensor 201 includes an optical module 210 and a control device 120. Although only one optical module 210 is shown in Figure 10, the measuring device 200 may include multiple optical modules 210 on a single base board 102.

[0088] The optical module 210 includes a light source 111, a first mirror 112, a first lens 113, a slit member 115, a prism 214, a second lens 116, and a second mirror 117. The prism 214 alters the optical path of the light source 111 so that light strikes the upper surface of the edge ring ER. In the illustrated example, the prism 214 is positioned on a straight line connecting the center of the light source 111 and the image sensor 118 and the center of the base substrate 102. At least a portion of the prism 214 is positioned outside the peripheral edge of the base substrate 102. In one exemplary embodiment, at least a portion of the prism 214 is located above the edge ring ER. The prism 214 may be fixed to the base substrate 102 by a support member (not shown), such as a support column, or by a fixing material (not shown), such as an adhesive.

[0089] Light output from the light source 111 is reflected by the first mirror 112 and input to the prism 214 via the first lens 113 and slit member 115. The light input to the prism 214 changes its optical path by being reflected by the reflective surface 214a. In one exemplary embodiment, the prism 214 is positioned to reflect the light from the light source 111 directly downwards. As a result, the light input to the prism 214 is irradiated onto the object (in one example, the edge ring ER). The light irradiated onto the object is then reflected by the reflective surface 214a of the prism 214 and input to the second mirror 117 via the second lens 116, and is reflected by the second mirror 117 and input to the image sensor 118.

[0090] Figure 11 is a schematic diagram illustrating the measurement principle of the measuring device 200. Note that, like the measuring device 100, the measuring device 200 calculates distance based on triangulation. In other words, the principle of distance measurement in the measuring device 200 is the same as the length measurement principle of the measuring device 100 described above, unless otherwise specified.

[0091] Figure 11 shows a prism 214 and an object 199. Here, the object 199 is a columnar body with a groove 199b formed on it. Light emitted from the light source 111 and formed into a line by the slit member 115 is reflected by the reflective surface 214a of the prism 214 and irradiates the object 199. In the illustrated example, the light is irradiated so as to straddle the groove 199b formed on the upper surface 199a of the columnar body. Note that in Figure 11, the light 112c and 112d irradiated onto the object 199 are emphasized in the drawing. The light reflected by the object 199 is reflected by the reflective surface 214a of the prism 214 and input to the image sensor 118 via the second lens 116 and the second mirror 117. As a result, an image of the object 199, including the position where the light is irradiated, is captured by the image sensor 118.

[0092] As shown in Figure 11, when the object 199 is imaged by the image sensor 118, the horizontal positions (horizontal coordinates) in the image of the light 112d in the groove 199b and the light 112c on the upper surface 199a are different. The control device 120 of one exemplary embodiment can derive the distance corresponding to the light 112d in the groove 199b and the distance corresponding to the light 112c on the upper surface 199a by referring to the distance (optical path length) calculated based on triangulation. In the measurement device 100 described above, the horizontal luminance waveform was extracted only at the vertical center position of the captured image. In the measurement device 200 shown in Figure 10, the horizontal luminance waveform is extracted at each position in the vertical coordinates of the captured image, and the distance corresponding to the peak coordinate of each extracted luminance waveform is calculated.

[0093] In one exemplary embodiment, the control device 120 can calculate the amount of wear on the edge ring ER, which is a consumable member, by irradiating the upper surface of the edge ring ER with light, as shown in Figure 10. For example, the control device 120 calculates the peak coordinates of the luminance waveform corresponding to each vertical position in the acquired image and acquires distance data corresponding to each calculated peak coordinate. By comparing the acquired distance data with reference distance data, the control device 120 can calculate the height position at each peak coordinate. For example, if the reference distance data corresponds to the height position of the bottom surface of the edge ring ER, the control device 120 can calculate the height of the edge ring ER. The control device 120 may store data of the optical path length corresponding to the height position of the bottom surface of the edge ring ER as reference distance data.

[0094] Figure 12 is a schematic diagram showing a cross-section of the edge ring ER. In Figure 12, the upper surface of an unworn edge ring ER is shown by a solid line, and an example of the upper surface of a worn edge ring ER is shown by a dashed line. In the illustrated example, the edge ring ER is significantly worn at the boundary between the first part P1 and the second part P2. Also, the edge ring ER is significantly worn at the outer edge of the second part P2. For example, consider the case where light formed into a line by the slit member 115 is irradiated so as to span the first part P1 and the second part P2. In this case, by acquiring the peak coordinates of the line-shaped light in the captured image over the entire vertical area of ​​the image, the optical path length corresponding to each peak coordinate is obtained. The control device 120 can obtain the height of the edge ring ER after wear at each peak coordinate by comparing the acquired optical path length with the optical path length corresponding to the height position of the bottom surface of the edge ring ER. In this example, the vertical direction of the image acquired by the image sensor 118 corresponds to the radial direction of the edge ring ER. Therefore, the control device 120 can derive profile data showing the change in the radial degree of wear of the edge ring ER by replacing the vertical coordinate with the radius of the edge ring ER (Figure 13).

[0095] The above explanation uses an edge ring ER as the target object, but the target object is not limited to the edge ring ER. For example, the measuring device may use the upper electrode as the target object. In this case, the degree of wear of the upper electrode can be obtained.

[0096] From the above description, it will be understood that the various embodiments of this disclosure are described herein for illustrative purposes and can be modified in various ways without departing from the scope and spirit of this disclosure. Accordingly, the various embodiments disclosed herein are not intended to limit the scope and spirit, and the true scope and spirit are shown by the appended claims.

[0097] Various exemplary embodiments included in this disclosure are described below. [E1] A substrate processing system comprising: a chamber defining a space inside; a first support disposed within the chamber; and a measuring device that can be mounted on the first support, wherein the measuring device comprises: a base substrate mounted on the first support; and a triangulation sensor mounted on the base substrate, the triangulation sensor comprising: a light source that emits light; and an image sensor that captures the light emitted from the light source onto an object, and the triangulation sensor derives the distance to the object by triangulation based on the image captured by the image sensor. [E2] The substrate processing system according to [E1], further comprising: a control device that compares the distance to the object measured by the triangulation sensor with a reference value of the distance from the triangulation sensor to the object that is stored in advance. [E3] The substrate processing system according to [E1] or [E2], wherein the triangulation sensors are provided at three or more spaced apart locations on the base substrate. [E4] The substrate processing system according to any one of [E1] to [E3], wherein the measuring device has an optical component that makes the light emitted from the light source into a line shape. [E5] The substrate processing system according to any one of [E1] to [E4], wherein the triangulation sensor measures the distance to the object based on the position of the light in the image captured by the image sensor. [E6] The substrate processing system according to any one of [E1] to [E5], further comprising a second support portion that is ring-shaped in plan view and surrounds the first support portion in the chamber, and a ring member placed on the second support portion. [E7] The substrate processing system according to [E6], wherein the object is the ring member, and the triangulation sensor emits light from the light source such that the light hits the inner surface of the ring member. [E8] The substrate processing system according to [E6], wherein the object is the ring member, and the triangulation sensor has an optical path changing member that controls the optical path of the light source so that the light strikes the upper surface of the ring member.[E9] The substrate processing system according to any one of [E1] to [E8], wherein the object is a consumable member, and the triangulation sensor calculates the amount of consumable member to be consumed based on the distance to the object. [E10] A method for acquiring the state of a substrate processing system, wherein the substrate processing system comprises: a chamber defining a space inside; a first support portion disposed within the chamber; and a measuring device that can be placed on the first support portion, and the measuring device comprises: a base substrate placed on the first support portion; and a triangulation sensor mounted on the base substrate, the triangulation sensor comprising: a light source that emits light; and an image sensor that images the light emitted from the light source onto an object, the method comprising: placing the measuring device on the first support portion; imaging the light with the image sensor while the light is emitted from the light source of the measuring device placed on the first support portion onto the object; measuring the distance between the measuring device and the object based on the triangulation method by referring to an image including the light captured by the image sensor; and acquiring the state of the substrate processing system based on the distance between the measuring device and the object.

[0098] 1... Processing system, 10... Plasma processing device (processing device), 100... Measuring device, 101... Triangulation sensor, 102... Base substrate, 111... Light source, 115... Slit member (optical component), 118... Image sensor, 120... Control device, 214... Prism (optical path changing member), ESC... Electrostatic chuck (first support part), ER... Edge ring (ring member, consumable member), S... Chamber.

Claims

1. A substrate processing system comprising: a chamber that defines a space inside; a first support portion disposed within the chamber; and a measuring device that can be mounted on the first support portion, wherein the measuring device comprises: a base substrate mounted on the first support portion; and a triangulation sensor mounted on the base substrate, the triangulation sensor comprising: a light source that emits light; and an image sensor that captures the light emitted from the light source onto an object; and the triangulation sensor that derives the distance between itself and the object by triangulation based on the image captured by the image sensor.

2. The substrate processing system according to claim 1, further comprising a control device that compares the distance to the object measured by the triangulation sensor with a reference value of the distance from the triangulation sensor to the object that is stored in advance.

3. The substrate processing system according to claim 1, wherein the triangulation sensors are provided at three or more locations on the base substrate that are spaced apart from each other.

4. The substrate processing system according to any one of claims 1 to 3, wherein the measuring device has an optical component that makes the light emitted from the light source into a line shape.

5. The substrate processing system according to any one of claims 1 to 3, wherein the triangulation sensor measures the distance to the object based on the position of the light in the image captured by the image sensor.

6. A substrate processing system according to any one of claims 1 to 3, further comprising: a second support portion that is ring-shaped in plan view and surrounds the first support portion within the chamber; and a ring member placed on the second support portion.

7. The substrate processing system according to claim 6, wherein the object is the ring member, and the triangulation sensor irradiates the ring member with light from the light source such that the light strikes the inner surface of the ring member.

8. The substrate processing system according to claim 6, wherein the object is the ring member, and the triangulation sensor has an optical path changing member that controls the optical path of the light source so that the light strikes the upper surface of the ring member.

9. The substrate processing system according to claim 1, wherein the object is a consumable member, and the triangulation sensor calculates the amount of consumable member worn based on the distance to the object.

10. A method for acquiring the state of a substrate processing system, wherein the substrate processing system comprises: a chamber defining a space inside; a first support portion disposed within the chamber; and a measuring device that can be placed on the first support portion, and the measuring device comprises: a base substrate placed on the first support portion; and a triangulation sensor mounted on the base substrate, the triangulation sensor comprising: a light source that emits light; and an image sensor that images the light emitted from the light source onto an object, the method comprising: placing the measuring device on the first support portion; imaging the light with the image sensor while the light is emitted from the light source of the measuring device placed on the first support portion onto the object; measuring the distance between the measuring device and the object based on the triangulation method by referring to an image including the light captured by the image sensor; and acquiring the state of the substrate processing system based on the distance between the measuring device and the object.

Images