KR20170142905A - Measuring instrument for measuring electrostatic capacity and method of calibrating transfer position data in processing system by using measuring instrument - Google Patents

Abstract

A measuring device for measuring capacitance is provided. The measuring device includes: a base substrate having a disc shape; a plurality of first sensors each providing a plurality of side electrodes arranged along an edge of the base substrate; one or more second sensors each having a bottom electrode provided along a bottom surface of the base substrate; and a circuit board. The circuit board is configured to apply a high-frequency signal to the plurality of side electrodes and the bottom electrodes so as to generate a plurality of first measured values indicating capacitance from each of the voltage amplitudes in the plurality of side electrodes and to generate a second measured value indicating capacitance from a voltage amplitude in the bottom electrode.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring instrument for measuring electrostatic capacitance and a method for calibrating a conveying position data in a processing system using a measuring instrument. 2. Description of the Related Art < RTI ID = 0.0 >

An embodiment of the present disclosure relates to a method for calibrating the conveying position data in a processing system using a measuring instrument for measuring capacitance and a measuring instrument.

BACKGROUND OF THE INVENTION [0002] In the manufacture of electronic devices such as semiconductor devices, processing systems for processing disk-shaped workpieces are used. The processing system has a transfer device for transferring the workpiece and a processing device for processing the workpiece. The processing apparatus generally has a chamber body and a mounting table provided in the chamber body. The mounting table is configured to support a workpiece placed thereon. The transfer device is configured to transfer the workpiece to the mount table.

In the processing of the workpiece in the processing apparatus, the position of the workpiece in the target table is important. Therefore, in the case where the position of the workpiece is deviated from the predetermined position on the mount table, it is necessary to adjust the transport apparatus.

As a technique for adjusting the transport apparatus, the technique described in Japanese Patent Publication No. 4956328 is known. In the technique described in this document, a concave portion is formed on the mount table. Further, in the technique described in this document, a measuring instrument having the same disk shape as that of the workpiece and having an electrode for capacitance measurement is used. In the technique described in this document, the measuring device is transported to the mounting table by the transporting device, and the measured value of the capacitance, which depends on the relative positional relationship between the recess and the electrode, is acquired. Based on the measured value, The transport device is adjusted to correct the position.

As a processing apparatus of the above-described processing system, a plasma processing apparatus may be used. The plasma processing apparatus, like the above-described processing apparatus, has a chamber body and a table. In the plasma processing apparatus, a focus ring is provided on the mount table so as to surround the edge of the workpiece. The focus ring is a ring-shaped plate extending in the peripheral direction with respect to the central axis, and is formed of, for example, silicon.

In the plasma processing for the workpiece using the plasma processing apparatus, the positional relationship between the focus ring and the workpiece is important. For example, when the position of the disk-shaped workpiece is shifted with respect to the focus ring, and the size of the gap between the focus ring and the edge of the workpiece fluctuates in the circumferential direction, And particles may be generated on the workpiece. Therefore, it is necessary to acquire highly reliable data reflecting the positional relationship between the workpiece and the focus ring carried by the transfer device.

In one aspect, a measuring instrument for measuring capacitance is provided. The measuring instrument includes a base substrate, a plurality of first sensors, at least one second sensor, and a circuit board. The base substrate has a disk shape. The plurality of first sensors are arranged along the edge of the base substrate and each provide a plurality of side electrodes. Each of the one or more second sensors has a bottom electrode provided along a bottom surface of the base substrate. The circuit board is mounted on a base substrate, and is connected to each of a plurality of first sensors and one or more second sensors. The circuit board generates a plurality of first measured values indicating the capacitance from each of the voltage amplitudes of the plurality of side electrodes by applying a high frequency signal to the plurality of side electrodes and the bottom electrode, The second measured value indicating the capacitance is generated from the voltage amplitude of the voltage.

In the measuring instrument according to one aspect, a plurality of side electrodes provided by the plurality of first sensors are arranged along the edge of the base substrate. In a state in which the measuring device is disposed in the region surrounded by the focus ring, the plurality of side electrodes face the inner edge of the focus ring. The plurality of first measured values generated from the voltage amplitudes of these side electrodes represent the electrostatic capacity reflecting the distance between each of the plurality of side electrodes and the focus ring. Therefore, according to this measuring instrument, measurement data reflecting the relative positional relationship between the measuring device and the focus ring imitating the workpiece is obtained. In this measuring instrument, the respective bottom electrodes of the at least one second sensor are disposed along the bottom surface of the base substrate. The second measured value generated from the voltage amplitude at the bottom electrode indicates the capacitance between the bottom electrode and the object below the measuring device. That is, the second measured value reflects the relative positional relationship between the bottom electrode and the object below the measuring device. Thus, according to the second measurement value, it is possible to confirm whether or not the measuring instrument is disposed on the target in the area surrounded by the focus ring. By using the second measured value, it becomes possible to confirm the reliability of the first measured value.

In one embodiment, each of the bottom electrodes of the at least one second sensor has a circular shape. Each of the one or more second sensors further includes a peripheral electrode arranged to surround the bottom electrode. The circuit board is further configured to apply a high frequency signal to the peripheral electrodes to produce a third measured value indicative of capacitance from the voltage amplitude at the peripheral electrode.

In one embodiment, the at least one second sensor is a plurality of second sensors. The plurality of second sensors are arranged along a circle that shares a center axis of the base substrate.

In one embodiment, each of the at least one second sensor further includes a plurality of electrodes provided on the base substrate so as to extend from the upper surface of the base substrate to the thickness direction of the base substrate. Each of the bottom electrodes of the at least one second sensor is formed by a cross-section of the bottom surface of the plurality of electrodes.

In one embodiment, each of the at least one second sensor further has at least one penetrating electrode penetrating the base substrate. Each of the bottom electrodes of the at least one second sensor is connected to the circuit board through at least one through electrode.

In one embodiment, the at least one second sensor is at least three second sensors. Each of the three or more second sensors is disposed along a circle that shares the central axis of the base substrate. A part of the edge of each of the bottom electrodes of the three or more second sensors has an arc shape and extends over the circle.

In another aspect, there is provided a method of calibrating carrier position data in a processing system using the above measuring instrument. The processing system includes a processing device and a transporting device. The processing apparatus has a chamber body and an electrostatic chuck. The electrostatic chuck is provided in the chamber provided by the chamber body. The electrostatic chuck has a witch area having a circular edge. The workpiece is placed on the placement area. The transport apparatus transports the workpiece on the placement area based on the transport position data. This method comprises the steps of transporting a measuring instrument using a transporting device at a position on a placement area specified by the transporting position data, measuring at least three electrostatic capacitances by at least three second sensors of the measuring device carried on the placement area A step of obtaining an error with respect to a predetermined conveying position on the placement area at a position on the placement area where the measuring instrument is conveyed from the measured values of the three or more electrostatic capacities and a step of calibrating the conveying position data using the error .

In one embodiment, the curvature of the portion of the edge of the bottom electrode coincides with the curvature of the edge of the placement area.

1 is a diagram illustrating a processing system.
2 is a perspective view illustrating an aligner.
3 is a diagram showing an example of a plasma processing apparatus.
4 is a plan view showing the electrostatic chuck.
5 is a perspective view illustrating a measuring instrument.
Fig. 6 is a plan view of the measuring instrument shown in Fig. 5 when viewed from the bottom surface side. Fig.
7 is a perspective view showing an example of the first sensor.
Fig. 8 is a cross-sectional view taken along the line VIII-VIII in Fig. 7. Fig.
9 is a cross-sectional view taken along the line IX-IX in Fig.
10 is a cross-sectional view taken along line XX of Fig.
11 is a diagram illustrating the configuration of a circuit board of a measuring instrument.
12 is a longitudinal sectional view showing another example of the first sensor.
13 is a diagram showing another example of the second sensor.
Fig. 14 is a cross-sectional view taken along the line XIV-XIV in Fig. 13 (b).
15 is a view showing still another example of the second sensor.
16 is a diagram showing still another example of the second sensor.
17 is a diagram showing another example of the measuring device.
18 is a cross-sectional view schematically showing an electrostatic chuck.
19 is an enlarged view of the measuring instrument of Fig.
20 is a diagram illustrating the configuration of a circuit board of the measuring instrument of Fig. 17;
21 is a flowchart showing an embodiment of a method of correcting the conveying position data in the processing system.
22 is a diagram showing the transport position of the measuring instrument with respect to the electrostatic chuck.

Hereinafter, various embodiments will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

First, a processing system having a processing device for processing a disk-shaped workpiece and a transfer device for transferring the object to be processed to the processing device will be described. 1 is a diagram illustrating a processing system. The processing system 1 includes the pedestals 2a to 2d, the containers 4a to 4d, the loader module LM, the aligner AN, the load lock modules LL1 and LL2, the process modules PM1 to PM6, A transfer module TF, and a control unit MC. However, the number of the pedestals 2a to 2d, the number of the containers 4a to 4d, the number of the load lock modules LL1 and LL2, and the number of the process modules PM1 to PM6 are not limited, Lt; / RTI >

The pedestals 2a to 2d are arranged along one edge of the loader module LM. The containers 4a to 4d are respectively mounted on the pedestals 2a to 2d. Each of the containers 4a to 4d is, for example, a container called FOUP (Front Opening Unified Pod). Each of the containers 4a to 4d is configured to receive a workpiece W therein. The workpiece W has a substantially disk shape like a wafer.

The loader module (LM) has a chamber wall defining therein a transfer space in an atmospheric pressure state. The carrying device TU1 is provided in the carrying space. The transport apparatus TU1 is, for example, a multi-joint robot, and is controlled by a control unit MC. The transport apparatus TU1 is provided between the containers 4a to 4d and the aligner AN, between the aligner AN and the load lock modules LL1 to LL2, between the load lock modules LL1 to LL2, 4a to 4d, the workpiece W is transported.

The aligner AN is connected to the loader module LM. The aligner AN is configured to adjust the position of the workpiece W (positional correction). 2 is a perspective view illustrating an aligner. The aligner AN has a support table 6T, a drive device 6D, and a sensor 6S. The support table 6T is a base rotatable about an axis extending in the vertical direction, and is configured to support the workpiece W thereon. The support table 6T is rotated by the drive device 6D. The drive unit 6D is controlled by the control unit MC. When the support table 6T is rotated by the power from the drive device 6D, the workpiece W placed on the support table 6T also rotates.

The sensor 6S is an optical sensor and detects the edge of the workpiece W while the workpiece W is being rotated. The sensor 6S calculates the shift amount of the angular position of the notch WN (or other marker) of the workpiece W with respect to the reference angle position and the shift amount of the workpiece W with respect to the reference position, As shown in Fig. The sensor 6S outputs the shift amount of the angular position of the notch WN and the shift amount of the center position of the workpiece W to the control unit MC. The control section MC calculates the rotation amount of the support table 6T for correcting the angular position of the notch WN to the reference angular position based on the shift amount of the angular position of the notch WN. The control unit MC controls the drive unit 6D so as to rotate the support table 6T by this amount of rotation. Thereby, the angular position of the notch WN can be corrected to the reference angular position. The control unit MC receives the workpiece W from the aligner AN so that the predetermined position on the end effector of the transport apparatus TU1 and the center position of the workpiece W coincide with each other The position of the end effector of the transfer device TU1 is controlled based on the shift amount of the center position of the work W.

Returning to Fig. 1, each of the load lock module LL1 and the load lock module LL2 is provided between the loader module LM and the transfer module TF. Each of the load lock module LL1 and the load lock module LL2 provides a preliminary vacuum chamber.

The transfer module TF is connected to the load lock module LL1 and the load lock module LL2 through a gate valve. The transfer module TF provides a decompression chamber capable of being depressurized. In this decompression chamber, a transport device TU2 is provided. The transport apparatus TU2 is, for example, a multi-joint robot, and is controlled by a control unit MC. The transport apparatus TU2 is provided between the load lock modules LL1 to LL2 and the process modules PM1 to PM6 and between any two of the process modules PM1 to PM6, As shown in Fig.

The process modules PM1 to PM6 are connected to the transfer module TF through a gate valve. Each of the process modules PM1 to PM6 is a processing device configured to perform a dedicated process such as a plasma process on the workpiece W.

A series of operations when processing of the workpiece W is performed in the processing system 1 are exemplified as follows. The transfer device TU1 of the loader module LM takes out the workpiece W from any of the containers 4a to 4d and transfers the workpiece W to the aligner AN. Next, the transfer apparatus TU1 takes out the workpiece W whose position has been adjusted from the aligner AN and transfers the workpiece W to one of the load lock module LL1 and the load lock module LL2 To the load-lock module of Fig. Then, one of the load lock modules reduces the pressure of the preliminary decompression chamber to a predetermined pressure. Subsequently, the transfer unit TU2 of the transfer module TF takes out the workpiece W from one of the load-lock modules and transfers the workpiece W to one of the process modules PM1 to PM6 . One or more process modules of the process modules PM1 to PM6 process the workpiece W. [ Then, the transfer apparatus TU2 transfers the processed workpiece W from the process module to one of the load lock module LL1 and the load lock module LL2. Then, the transfer device TU1 transfers the workpiece W from one of the load lock modules to any one of the containers 4a to 4d.

The processing system 1 includes a control unit MC as described above. The control unit MC may be a computer having a processor, a storage device such as a memory, a display device, an input / output device, a communication device, and the like. The series of operations of the processing system 1 described above is realized by control of each part of the processing system 1 by the control unit MC according to the program stored in the storage device.

3 is a diagram showing an example of a plasma processing apparatus that can be employed as any of the process modules PM1 to PM6. The plasma processing apparatus 10 shown in Fig. 3 is a capacitively coupled plasma etching apparatus. The plasma processing apparatus 10 is provided with a substantially cylindrical chamber body 12. The chamber body 12 is made of, for example, aluminum, and an inner wall surface thereof may be anodized. The chamber body 12 is grounded.

On the bottom of the chamber body 12, a substantially cylindrical support portion 14 is provided. The supporting portion 14 is made of, for example, an insulating material. The support portion 14 is provided in the chamber body 12 and extends upward from the bottom portion of the chamber body 12. In the chamber S provided by the chamber main body 12, a mounting table PD is provided. The mounting table PD is supported by the supporting portion 14. [

The mounting table PD 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, for example, metal such as aluminum and have a substantially disk shape. The second plate 18b is provided on the first plate 18a and is electrically connected to the first plate 18a.

On the second plate 18b, an electrostatic chuck ESC is provided. The electrostatic chuck ESC has a structure in which an electrode serving as a conductive film is disposed between a pair of insulating layers or insulating sheets and has a substantially disk shape. A DC power supply 22 is electrically connected to an electrode of the electrostatic chuck ESC via a switch 23. [ The electrostatic chuck ESC draws the workpiece W to the electrostatic chuck ESC by electrostatic force such as Coulomb force generated by the DC voltage from the direct current power supply 22. Thus, the electrostatic chuck (ESC) can hold the workpiece W.

On the periphery of the second plate 18b, a focus ring FR is provided. The focus ring FR is provided so as to surround the edge of the workpiece W and the electrostatic chuck ESC. The focus ring FR has a first portion P1 and a second portion P2 (see Fig. 8). The first portion P1 and the second portion P2 have a ring-like plate shape. The second portion P2 is provided on the first portion P1. The inner edge P2i of the second portion P2 has a diameter larger than the diameter of the inner edge P1i of the first portion P1. The workpiece W is mounted on the electrostatic chuck ESC such that the edge region thereof is positioned on the first portion P1 of the focus ring FR. The focus ring FR may be formed of any one of various materials such as silicon, silicon carbide, and silicon oxide.

A refrigerant passage (24) is provided in the second plate (18b). The refrigerant flow path 24 constitutes a temperature adjusting mechanism. The refrigerant is supplied to the refrigerant passage 24 from the chiller unit provided outside the chamber body 12 through the pipe 26a. The refrigerant supplied to the refrigerant passage (24) is returned to the chiller unit through the pipe (26b). Thus, the refrigerant is circulated between the refrigerant passage (24) and the chiller unit. By controlling the temperature of the refrigerant, the temperature of the workpiece W supported by the electrostatic chuck ESC is controlled.

A plurality of (for example, three) through holes 25 penetrating the mounting table PD are formed on the mounting table PD. A plurality of (for example, three) lift pins 25a are inserted into the plurality of through holes 25, respectively. In Fig. 3, one through hole 25 into which one lift pin 25a is inserted is drawn.

Fig. 4 is a plan view showing the electrostatic chuck ESC constituting the mounting table PD. As shown in Fig. 4, the plurality of lift pins 25a have a plurality of straight lines orthogonal to the circle sharing the central axis of the electrostatic chuck ESC, that is, the center axis of the placement stand PD and extending in the vertical direction Respectively. The plurality of lift pins 25a may be disposed at regular intervals in the circumferential direction with respect to the central axis line. These lift pins 25a are supported on a link that ascends and descends by, for example, an actuator. The lift pin 25a supports the workpiece W at the tip of the lift pin 25a in a state in which the tip of the lift pin 25a protrudes above the electrostatic chuck ESC. After this, the lift pin 25a descends, and the workpiece W is placed on the electrostatic chuck ESC. After the plasma processing of the workpiece W, the lift pin 25a rises to separate the workpiece W from the electrostatic chuck ESC. That is, the lift pin 25a is used for loading and unloading the workpiece W.

In the plasma processing apparatus 10, a gas supply line 28 is provided. The gas supply line 28 supplies a heat transfer gas, for example, He gas, from the heat transfer gas supply mechanism between the upper surface of the electrostatic chuck ESC and the back surface of the work W.

The plasma processing apparatus 10 includes an upper electrode 30. The upper electrode 30 is disposed above the mounting table PD so as to face the mounting table PD. The upper electrode 30 is supported on the upper portion of the chamber main body 12 through the insulating shield member 32. The top electrode 30 may include a top plate 34 and a support 36. The ceiling plate 34 faces the chamber S. [ The ceiling plate 34 is provided with a plurality of gas discharge holes 34a. The ceiling plate 34 may be formed of silicon or quartz. Alternatively, the ceiling plate 34 can be constituted by forming a plasma-resistant film such as yttrium on the surface of the base material made of aluminum.

The support member 36 detachably supports the ceiling plate 34. [ The support body 36 may be made of a conductive material such as aluminum, for example. The support body 36 may have a water cooling structure. A gas diffusion chamber (36a) is provided in the support (36). From the gas diffusion chamber 36a, a plurality of gas communication holes 36b communicating with the gas discharge holes 34a extend downward. The support body 36 is provided with a gas introduction port 36c for introducing the process gas into the gas diffusion chamber 36a. A gas supply pipe 38 is connected to the gas introduction port 36c.

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

In the plasma processing apparatus 10, a shield 46 is detachably provided along the inner wall of the chamber main body 12. The shield (46) is also provided on the outer periphery of the support portion (14). The shield 46 prevents the etch by-product from adhering to the chamber body 12. The shield 46 may be formed by coating an aluminum material with ceramics such as yttrium oxide.

An exhaust plate 48 is provided on the bottom side of the chamber body 12 and also between the support 14 and the side wall of the chamber body 12. The exhaust plate 48 may be constituted by, for example, covering an aluminum material with ceramics such as yttrium oxide. The exhaust plate (48) is provided with a plurality of holes penetrating in the thickness direction thereof. An exhaust port 12e is provided below the exhaust plate 48 and in the chamber main body 12. An exhaust device 50 is connected to the exhaust port 12e through an exhaust pipe 52. [ The exhaust device 50 has a vacuum pump such as a pressure adjusting valve and a turbo-molecular pump, so that the space in the chamber body 12 can be reduced to a desired degree of vacuum. An opening 12g for carrying in or out the workpiece W is provided on the side wall of the chamber body 12. [ The opening 12g is openable and closable by a gate valve 54. [

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 source 62 is a power source for generating a first high frequency for generating plasma, and generates a high frequency having a frequency of 27 to 100 MHz, for example. The first high frequency power source 62 is connected to the upper electrode 30 through the matching unit 66. The matching device 66 has a circuit for matching the output impedance of the first high frequency power supply 62 with the input impedance of the load side (the upper electrode 30 side). The first high frequency power supply 62 may be connected to the lower electrode LE through the matching unit 66. [

The second high frequency power source 64 is a power source for generating a second high frequency for drawing ions into the workpiece W and generates a high frequency of a frequency within a range of 400 kHz to 13.56 MHz, for example. The second high frequency power supply 64 is connected to the lower electrode LE through the matching unit 68. [ The matching device 68 has a circuit for matching the output impedance of the second high frequency power supply 64 with the input impedance of the load side (the lower electrode LE side).

In the plasma processing apparatus 10, a gas from at least one gas source selected from a plurality of gas sources is supplied to the chamber S. In addition, the pressure of the chamber S is set to a predetermined pressure by the exhaust device 50. In addition, the gas in the chamber S is excited by the first high frequency power from the first high frequency power supply 62. This creates a plasma. Then, the workpiece W is processed by the generated active species. If necessary, ions may be drawn into the workpiece W by a bias based on the second high frequency power of the second high frequency power supply 64. [

Hereinafter, the measuring instrument will be described. 5 is a perspective view illustrating a measuring instrument. Fig. 6 is a plan view of the measuring instrument shown in Fig. 5 when viewed from the bottom surface side. Fig. The measuring instrument 100 shown in Figs. 5 and 6 has a base substrate 102. Fig. The base substrate 102 is made of, for example, silicon and has the same shape as that of the workpiece W, that is, a substantially disk shape. The diameter of the base substrate 102 is equal to the diameter of the workpiece W, for example, 300 mm. The shape and dimensions of the measuring instrument 100 are defined by the shape and dimensions of the base substrate 102. Therefore, the measuring instrument 100 has the same shape as that of the workpiece W, and has the same dimensions as the dimensions of the workpiece W. [ In addition, a notch 102N (or another marker) is formed on the edge of the base substrate 102.

The base substrate 102 has a lower portion 102a and an upper portion 102b. The lower portion 102a is a portion located closer to the electrostatic chuck ESC than the upper portion 102b when the measuring instrument 100 is disposed above the electrostatic chuck ESC. On the lower portion 102a of the base substrate 102, a plurality of first sensors 104A to 104D for measuring capacitance are provided. However, the number of the first sensors provided in the measuring instrument 100 may be an arbitrary number of three or more. The plurality of first sensors 104A to 104D are arranged at equal intervals along the edge of the base substrate 102, for example, the entire periphery of the edge. Specifically, the front end face 104f of each of the plurality of first sensors 104A to 104D is provided so as to follow the edge of the lower portion 102a of the base substrate 102. [

The upper surface of the upper portion 102b of the base substrate 102 provides a concave portion 102r. The concave portion 102r includes a central region 102c and a plurality of radiation regions 102h. The central region 102c is an area intersecting the center axis AX100. The central axis AX100 is an axis passing through the center of the base substrate 102 in the thickness direction. In the central region 102c, a circuit board 106 is provided. The plurality of radiation regions 102h extend in the radial direction from the central region 102c to the upper side of the region where the plurality of first sensors 104A to 104D are arranged with respect to the central axis AX100. In the plurality of radiation regions 102h, wiring groups 108A to 108D are provided. The wiring groups 108A to 108D electrically connect the plurality of first sensors 104A to 104D to the circuit board 106, respectively. The plurality of first sensors 104A to 104D may be provided on the upper portion 102b of the base substrate 102. [

The base substrate 102 is provided with a plurality of second sensors 105A to 105C for measuring electrostatic capacitance. However, the number of the second sensors provided in the measuring instrument 100 may be an arbitrary number of one or more. In one embodiment, the three second sensors 105A to 105C are arranged at regular intervals in the circumferential direction along a circle sharing the central axis AX100 of the base substrate 102. [ The distance between the bottom electrode of each of the second sensors 105A to 105C and the center axis AX100 is set to be shorter than the distance between the central axis of the table PD and each of the lift pins 25a Can be roughly matched.

Hereinafter, the first sensor will be described in detail. 7 is a perspective view showing an example of a sensor. Fig. 8 is a cross-sectional view taken along the line VIII-VIII in Fig. 7, showing the base substrate and the focus ring of the measuring instrument together with the sensor. 9 is a cross-sectional view taken along the line IX-IX in Fig. The first sensor 104 shown in Figs. 7 to 9 is a sensor used as a plurality of first sensors 104A to 104D of the measuring instrument 100, and in one example, is configured as a chip-shaped component. In the following description, the XYZ orthogonal coordinate system is referred to as appropriate. The X direction represents the front direction of the first sensor 104. The Y direction represents the width direction of the first sensor 104 as one direction orthogonal to the X direction and the Z direction represents X And an upward direction of the first sensor 104 as a direction orthogonal to the Y direction.

7 to 9, the first sensor 104 includes a front side end face 104f, an upper face 104t, a bottom face 104b, a pair of side faces 104s, And a rear end face 104r. The front end surface 104f constitutes the front surface of the first sensor 104 in the X direction. The first sensor 104 is mounted on the base substrate 102 of the measuring instrument 100 so that the front end face 104f faces the radial direction with respect to the central axis AX100. In a state in which the first sensor 104 is mounted on the base substrate 102, the front end face 104f extends along the edge of the base substrate 102. [ Therefore, in a state where the measuring instrument 100 is disposed on the electrostatic chuck ESC, the front end face 104f faces the inner edge of the focus ring FR.

The rear end face 104r constitutes the rear surface of the first sensor 104 in the X direction. The rear end face 104r is located closer to the central axis AX100 than the front end face 104f in a state where the first sensor 104 is mounted on the base substrate 102. [ The upper surface 104t constitutes the upper surface of the first sensor 104 in the Z direction. And the lower surface 104b constitutes the lower surface of the first sensor 104 in the Z direction. The pair of side surfaces 104s constitute the surface of the first sensor 104 in the Y direction.

The first sensor 104 has an electrode (side electrode) 143. The first sensor 104 may further include an electrode 141 and an electrode 142. The electrode 141 is formed of a conductor. The electrode 141 has a first portion 141a. As shown in Figs. 7 and 8, the first portion 141a extends in the X and Y directions.

The electrode 142 is formed of a conductor. The electrode 142 has a second portion 142a. The second portion 142a extends above the first portion 141a. In the first sensor 104, the electrode 142 is insulated from the electrode 141. As shown in Figs. 7 and 8, the second portion 142a extends in the X direction and the Y direction on the first portion 141a.

The electrode 143 is a sensor electrode formed of a conductor. The electrode 143 is provided on the first portion 141a of the electrode 141 and on the second portion 142a of the electrode 142. [ The electrode 143 is insulated from the electrode 141 and the electrode 142 in the first sensor 104. The electrode 143 has a front surface 143f. The front surface 143f extends in the direction intersecting the first portion 141a and the second portion 142a. The front surface 143f extends along the front end surface 104f of the first sensor 104. [ In one embodiment, the front surface 143f constitutes a part of the front end surface 104f of the first sensor 104. [ Alternatively, the first sensor 104 may have an insulating film covering the front surface 143f on the front side of the front surface 143f of the electrode 143. [

7 to 9, the electrode 141 and the electrode 142 are opened in the region (X direction) of the region where the front face 143f of the electrode 143 is disposed, As shown in Fig. That is, the electrode 141 and the electrode 142 may extend upwardly, rearwardly, and laterally of the electrode 143 so as to surround the electrode 143.

In addition, the front end face 104f of the first sensor 104 may be a curved surface having a predetermined curvature. In this case, the front end face 104f has a certain curvature at an arbitrary position on the front end face. The curvature of the front end face 104f may be an inverse of the distance between the center axis AX100 of the measuring instrument 100 and the front end face 104f. The first sensor 104 is mounted on the base substrate 102 such that the center of curvature of the front end face 104f coincides with the center axis AX100.

The first sensor 104 may further have a substrate portion 144, insulating regions 146 to 148, pads 151 to 153, and via wiring 154. The substrate portion 144 has a body portion 144m and a surface layer portion 144f. The body portion 144m is made of, for example, silicon. The surface layer portion 144f covers the surface of the main body portion 144m. The surface layer portion 144f is formed of an insulating material. The surface layer 144f is, for example, a thermal oxide film of silicon.

The second portion 142a of the electrode 142 extends below the substrate portion 144. [ An insulating region 146 is provided between the substrate portion 144 and the electrode 142. The insulating region 146 is formed of, for example, SiO ₂ , SiN, Al ₂ O ₃ , or polyimide.

The first portion 141a of the electrode 141 extends below the second portion 142a of the substrate portion 144 and the electrode 142. [ An insulating region 147 is provided between the electrode 141 and the electrode 142. The insulating region 147 is formed of, for example, SiO ₂ , SiN, Al ₂ O ₃ , or polyimide.

The insulating region 148 constitutes the upper surface 104t of the first sensor 104. [ The insulating region 148 is formed of, for example, SiO ₂ , SiN, Al ₂ O ₃ , or polyimide. In the insulating region 148, pads 151 to 153 are formed. The pad 153 is formed of a conductor, and is connected to the electrode 143. Concretely, the electrode 143 and the pad 153 are connected to each other by the via wiring 154 passing through the insulating region 146, the electrode 142, the insulating region 147, and the electrode 141 have. An insulating material is provided around the via wiring 154, and the via wiring 154 is insulated from the electrode 141 and the electrode 142. The pad 153 is connected to the circuit board 106 via the via wiring 123 provided in the base substrate 102 and the wiring 183 provided in the radiation region 102h of the concave portion 102r. The pad 151 and the pad 152 are likewise formed of a conductor. The pad 151 and the pad 152 are respectively connected to the electrode 141 and the electrode 142 through corresponding via wiring. The pads 151 and the pads 152 are connected to the circuit board 106 via corresponding via wiring provided in the base substrate 102 and corresponding wiring provided in the radiation region 102h of the concave portion 102r do.

Hereinafter, the second sensor will be described in detail. 10 is a cross-sectional view taken along the line X-X in FIG. Fig. 10 shows a state in which the measuring instrument 100 is supported by the lift pin 25a. Reference is now made to Figs. 5, 6, and 10. Fig. Each of the second sensors 105A to 105C includes a bottom electrode 161. In one embodiment, each of the second sensors 105A to 105C further includes the peripheral electrodes 162a to 162d and the penetrating electrodes 165a to 165e. The bottom electrode 161 and the peripheral electrodes 162a to 162d are formed along the bottom surface of the base substrate 102. [ The penetrating electrodes 165a to 165e penetrate the base substrate 102. The bottom electrode 161, the peripheral electrodes 162a to 162d, and the penetrating electrodes 165a to 165e are formed of conductors.

The bottom electrode 161 may have a circular shape. The size of the bottom electrode 161 is, for example, approximately the same as the size of the top surface of the lift pin 25a. The peripheral electrodes 162a to 162d are arranged in a circle surrounding the bottom electrode 161. [ Each of the peripheral electrodes 162a to 162d has a planar shape defined by two arcs that share the center of the bottom electrode 161 and have different radii. The peripheral electrodes 162a to 162d are arranged in the circumferential direction with respect to the center of the bottom electrode 161. [ On the bottom surface of the base substrate 102, an insulating film 169 is formed. The insulating film 169 covers the bottom electrode 161 and the peripheral electrodes 162a to 162d. The insulating film 169 is made of, for example, SiO ₂ , SiN, Al ₂ O ₃ , or polyimide.

One ends of the plurality of penetrating electrodes 165a to 165e are connected to the peripheral electrodes 162a to 162d and the bottom electrode 161, respectively. The other end of each of the plurality of penetrating electrodes 165a to 165e is electrically connected to the circuit board 106 (see Fig. 5). The plurality of penetrating electrodes 165a to 165e may be formed using, for example, a TSV (Through-Silicon Via) technique.

Hereinafter, the configuration of the circuit board 106 will be described. 11 is a diagram illustrating the configuration of a circuit board of a measuring instrument. 11, the circuit board 106 includes a high-frequency oscillator 171, a plurality of C / V conversion circuits 172A to 172D, a plurality of C / V conversion circuits 180A to 180O, an A / A memory 173, a processor 174, a storage device 175, a communication device 176, and a power source 177. [

Each of the plurality of first sensors 104A to 104D is connected to the circuit board 106 through a corresponding one of the plurality of wiring groups 108A to 108D. Each of the plurality of first sensors 104A to 104D is connected to a corresponding C / V conversion circuit among a plurality of C / V conversion circuits 172A to 172D via several wirings included in the corresponding wiring group Respectively. Each of the plurality of second sensors 105A to 105C is connected to a corresponding one of the plurality of C / V converting circuits 180A to 180O via a plurality of wiring lines 184 Five C / V conversion circuits). The wiring group 108, which is one of the same configurations as each of the first sensor 104 and the plurality of wiring groups 108A to 108D, which is one of the configurations of the plurality of first sensors 104A to 104D, The C / V conversion circuit 172, which is one of the same configurations as each of the plurality of the C / V conversion circuits 172A to 172D, and the second sensor 174, which is one of the same configurations as each of the plurality of second sensors 105A to 105C, The C / V conversion circuit 180 having the same configuration as that of each of the plurality of C / V conversion circuits 180A to 180O will be described.

The wiring group 108 includes wirings 181 to 183. One end of the wiring 181 is connected to the pad 151 connected to the electrode 141. This wiring 181 is connected to the ground potential line GL connected to the ground GC of the circuit board 106. [ The wiring 181 may be connected to the ground potential line GL via the switch SWG. One end of the wiring 182 is connected to the pad 152 connected to the electrode 142 and the other end of the wiring 182 is connected to the C / V conversion circuit 172. One end of the wiring 183 is connected to the pad 153 connected to the electrode 143 and the other end of the wiring 183 is connected to the C / V conversion circuit 172.

The peripheral electrodes 162a to 162d and the bottom electrode 161 of the second sensor 105 are connected to the circuit board 106 individually. That is, the penetrating electrodes 165a to 165d connected to the peripheral electrodes 162a to 162d and the penetrating electrode 165e connected to the bottom electrode 161 are connected to a plurality of C / V And is connected to the conversion circuit 180 (five C / V conversion circuits in one embodiment).

The high-frequency oscillator 171 is connected to a power source 177 such as a battery and is configured to receive a power from the power source 177 and generate a high-frequency signal. The power source 177 is also connected to the processor 174, the storage device 175, and the communication device 176. The high-frequency oscillator 171 has a plurality of output lines. The high-frequency oscillator 171 applies the generated high-frequency signal to the wiring 182, the wiring 183, and the wiring 184 through a plurality of output lines. Therefore, the high-frequency oscillator 171 is electrically connected to the electrode 142 and the electrode 143 of the first sensor 104, and a high-frequency signal from the high-frequency oscillator 171 is supplied to the electrode 142 and the electrode 143, (143). The high-frequency oscillator 171 is electrically connected to the bottom electrode 161 and the peripheral electrodes 162a to 162d of the second sensor 105. The high-frequency signal from the high- And is applied to the auxiliary electrode 161 and the peripheral electrodes 162a to 162d.

A wiring 182 and a wiring 183 are connected to the input of the C / V conversion circuit 172. That is, the electrode 142 and the electrode 143 of the first sensor 104 are connected to the input of the C / V conversion circuit 172. The bottom electrode 161 and the peripheral electrodes 162a to 162d are connected to the inputs of the plurality of C / V conversion circuits 180, respectively. Each of the C / V conversion circuit 172 and the C / V conversion circuit 180 generates a voltage signal from the voltage amplitude at its input. The voltage signal indicates the capacitance of the electrode connected to the input. Each of the C / V conversion circuit 172 and the C / V conversion circuit 180 outputs the voltage signal. Further, the larger the electrostatic capacitance of the electrode connected to the C / V conversion circuit 172, the larger the voltage of the voltage signal outputted from the C / V conversion circuit 172 becomes. Similarly, the larger the capacitance of the electrode connected to the C / V conversion circuit 180, the larger the voltage of the voltage signal output from the C / V conversion circuit 180 becomes.

The outputs of the plurality of C / V conversion circuits 172A to 172D and the plurality of C / V conversion circuits 180A to 180O are connected to the input of the A / D converter 173. The A / D converter 173 is connected to the processor 174. The A / D converter 173 is controlled by a control signal from the processor 174 and is controlled by the output signals (voltage signals) of the plurality of C / V conversion circuits 172A to 172D and the plurality of C / 180A to 180O) into a digital value. That is, the A / D converter 173 generates a first measured value indicating the capacitance of each electrode 143 of the first sensors 104A to 104D. The A / D converter 173 generates a second measured value indicating the capacitance of each of the bottom electrodes 161 of the second sensors 105A to 105C and outputs the second measured value to the second sensors 105A to 105C A plurality of third measured values indicating the capacitances of the respective peripheral electrodes 162a to 162d of the respective first and second measurement electrodes 162a to 162d. The A / D converter 173 outputs the first measured value, the second measured value, and the third measured value to the processor 174.

A processor 175 is connected to the processor 174. The storage device 175 is a storage device such as a volatile memory and is configured to store measurement data to be described later. The processor 174 is connected to another storage device 178. [ The storage device 178 is a storage device such as a nonvolatile memory, and stores a program read by the processor 174 and executed.

The communication device 176 is a communication device conforming to any wireless communication standard. For example, the communication device 176 conforms to Bluetooth (registered trademark). The communication device 176 is configured to wirelessly transmit the measurement data stored in the storage device 175. [

The processor 174 is configured to control each part of the measuring instrument 100 by executing the above-described program. For example, the processor 174 supplies the high-frequency signal from the high-frequency oscillator 171 to the electrode 142, the electrode 143, the bottom electrode 161, and the peripheral electrodes 162a to 162d, Power is supplied from the power source 177 to the device 175, power is supplied from the power source 177 to the communication device 176, and the like. The processor 174 executes the above-described program to acquire the first to third measured values, store the first to third measured values in the storage device 175, and store the first to third measured values And the like.

In the measuring instrument 100 described above, a plurality of electrodes 143 (side electrodes) provided by the first sensors 104A to 104D are arranged along the edge of the base substrate 102. [ In a state in which the measuring instrument 100 is disposed in the region surrounded by the focus ring FR, the plurality of electrodes 143 face the inner edge of the focus ring FR. The plurality of first measured values generated from the voltage amplitudes of these electrodes 143 represent electrostatic capacities reflecting the distance between each of the plurality of electrodes 143 and the focus ring. The capacitance C is expressed by C = epsilon S / d. is the dielectric constant of the medium between the front surface 143f of the electrode 143 and the inner edge of the focus ring FR, S is the area of the front surface 143f of the electrode 143, Can be regarded as the distance between the front edge 143f and the inner edge of the focus ring FR. Therefore, the measuring instrument 100 obtains measurement data reflecting the relative positional relationship between the measuring instrument 100 and the focus ring FR, which imitates the workpiece W. [ For example, a plurality of first measured values acquired by the measuring instrument 100 becomes smaller as the distance between the front surface 143f of the electrode 143 and the inner edge of the focus ring FR becomes larger.

In the measuring instrument 100, the bottom electrodes 161 of the second sensors 105A to 105C are disposed along the bottom surface of the base substrate 102, respectively. The second measured value generated from the voltage amplitude of the bottom electrode 161 indicates the capacitance between the bottom electrode 161 and the object below the measuring device 100. [ That is, the second measured value reflects the relative positional relationship between the bottom electrode 161 and the object below the measuring device 100. [ In one embodiment, the second measured value reflects the relative positional relationship between the bottom electrode 161 and the lift pin 25a, which is an object below the measuring instrument 100. [ Specifically, the second measured value increases when the bottom electrode 161 and the tip of the lift pin 25a face each other. On the other hand, the second measured value becomes smaller when the position of the bottom electrode 161 deviates from the tip end position of the lift pin 25a. As described above, the positional relationship between the bottom electrode 161 of each of the second sensors 105A to 105C and the center axis AX100 of the measuring instrument 100 is determined by the position of each of the lift pins 25a, Substantially coincides with the positional relationship of the center axis of the PD. Therefore, when the second measured value is a predetermined value or more, it can be confirmed that the measuring instrument 100 is disposed in the area surrounded by the focus ring FR by the descent of the lift pin 25a. Therefore, according to the second measurement value, it can be confirmed whether the measuring instrument 100 is placed on the placement stand PD in the area surrounded by the focus ring FR. By using the second measured value, it becomes possible to confirm the reliability of the first measured value. Therefore, with the measuring instrument 100, it becomes possible to acquire highly reliable data reflecting the positional relationship between the measuring instrument 100 and the focus ring FR, which imitates the workpiece W. [

Each of the second sensors 105A to 105C is provided with the peripheral electrodes 162a to 162d so as to surround the bottom electrode 161. [ By using a plurality of third measured values obtained from the voltage amplitudes of these peripheral electrodes 162a to 162d together with the second measured value, the measuring instrument 100 can be placed in the area surrounded by the focus ring FR It can be more accurately confirmed whether or not it is placed on the PD.

As described above, in the first sensor 104 mounted on the measuring instrument 100, the electrode 143 (sensor electrode) is provided on the electrode 141, and the electrode 141 A second portion of the electrode 142 is interposed. When the first sensor 104 is used, the switch SWG is closed, and the potential of the electrode 141 is set to the ground potential. Then, a high frequency signal is supplied to the electrode 142 and the electrode 143. At this time, the voltage amplitude of the electrode 143 is not influenced by the capacitance of the electrode 141 from the direction in which the electrode 141 is provided, that is, from the lower side of the first sensor 104, Becomes a voltage amplitude reflecting the electrostatic capacitance in the direction (X direction) in which the front surface 143f of the electrode 143 faces. Therefore, according to the first sensor 104, the capacitance can be measured with high directivity in a specific direction.

The electrode 141 and the electrode 142 extend in the direction of the region (X direction) of the region where the front surface of the electrode 143 is disposed and also surround the periphery of the electrode 143. Therefore, the electrode 141 and the electrode 142 shield the electrode 143 in directions other than the specific direction. Therefore, in the measurement of the capacitance, the directivity of the first sensor 104 with respect to a specific direction is further improved.

The front end face 104f of the first sensor 104 is formed as a curved face having a predetermined curvature and the front face 143f of the electrode 143 extends along the front end face 104f. Therefore, the distance in the radial direction between each position of the front face 143f of the electrode 143 and the inner edge of the focus ring FR can be set to be substantially equal. Therefore, the precision of the measurement of the capacitance is further improved.

Hereinafter, another example of the first sensor that can be mounted on the measuring instrument 100 will be described. 12 is a longitudinal sectional view showing another example of the first sensor. 12 shows a vertical cross-sectional view of the first sensor 204, and a focus ring FR is shown together with the first sensor 204. As shown in FIG.

The first sensor 204 has an electrode 241, an electrode 242, and an electrode 243. The first sensor 204 may further have a substrate portion 244 and an insulating region 247. The substrate portion 244 has a body portion 244m and a surface layer portion 244f. The body portion 244m is made of, for example, silicon. The surface layer 244f covers the surface of the main body 244m. The surface layer 244f is formed of an insulating material. The surface layer 244f is, for example, a thermal oxide film of silicon.

The substrate portion 244 has an upper surface 244a, a lower surface 244b, and a front end surface 244c. The electrode 242 is provided below the lower surface 244b of the substrate portion 244 and extends in the X and Y directions. The electrode 241 is provided below the electrode 242 through the insulating region 247 and extends in the X and Y directions.

The front end face 244c of the base portion 244 is formed in a stepped shape. The lower portion 244d of the front end face 244c protrudes toward the side of the focus ring FR than the upper portion 244u of the front end face 244c. The electrode 243 extends along the upper portion 244u of the front end face 244c.

When the first sensor 204 is used as the sensor of the measuring instrument 100, the electrode 241 is connected to the wiring 181, the electrode 242 is connected to the wiring 182, And is connected to the wiring 183.

In the first sensor 204, the electrode 243 serving as the sensor electrode is shielded from below the first sensor 204 by the electrode 241 and the electrode 242. Therefore, the first sensor 204 can measure the electrostatic capacitance with high directivity in a specific direction, that is, in the direction (X direction) in which the front surface 243f of the electrode 243 is oriented.

Hereinafter, another example of the second sensor that can be mounted on the measuring instrument 100 instead of the second sensors 105A to 105C will be described. FIG. 13A is a plan view showing a plurality of electrodes of a second sensor of another example as viewed from the bottom surface side of the measuring instrument, and FIG. 13B is a plan view showing the second sensor as seen from the upper surface side of the measuring instrument. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 13 (b). 14 shows a state in which the measuring instrument 100 is supported by the lift pin 25a.

The second sensor 305 includes a plurality of electrodes 365. The plurality of electrodes 365 are provided on the base substrate 102 so as to extend from the upper surface of the base substrate 102 to the thickness direction of the base substrate 102. In the second sensor 305, a plurality of electrodes 365 pass through the base substrate 102. Each of the plurality of electrodes 365 provides a cross section 365a on the side of the bottom surface of the base substrate 102. [ The end face 365a of the plurality of electrodes 365 constitutes a bottom electrode and a plurality of peripheral electrodes. Concretely, as shown in FIG. 13 (a), a cross section 365a of several electrodes 365 existing in a central circular region 361 among the cross-sections 365a of the plurality of electrodes 365, Constitute a bottom electrode. The end surface 365a of several electrodes 365 present in each of the peripheral regions 362a to 362d surrounding the region 361 constitutes a peripheral electrode. In the example shown in Fig. 13, the number of peripheral regions is four. These peripheral regions 362a to 362d are defined by two arcs having different radii and arranged in the circumferential direction with respect to the center of the region 361. [ As shown in FIG. 14, an insulating film 169 is formed on the bottom surface of the base substrate 102. The insulating film 169 covers the end face 365a of the plurality of electrodes 365. [

The upper surface of the base substrate 102 is provided with pattern electrodes 366a and 362b which are opposed to the peripheral regions 362a to 362d and the region 361 and which have substantially the same shape as the peripheral regions 362a to 362d and the region 361, To 366e are formed. The electrode 365 providing the end face 365a in the peripheral region 362a is connected to the pattern electrode 366a. The electrode 365 providing the end face 365a in the peripheral region 362b is connected to the pattern electrode 366b. The electrode 365 providing the end face 365a in the peripheral region 362c is connected to the pattern electrode 366c. The electrode 365 providing the end face 365a in the peripheral region 362d is connected to the pattern electrode 366d. The electrode 365 providing the end face 365a in the region 361 is connected to the pattern electrode 366e. In the fabrication of each of the above-described second sensors 105A to 105C, a step of forming a bottom electrode and a peripheral electrode separately from the penetrating electrodes 165a to 165e is required. On the other hand, in the second sensor 305, since the plurality of electrodes 365 extending in the thickness direction of the base substrate 102 as the penetrating electrodes 165a to 165e provide the bottom electrode and the peripheral electrode, A separate step of forming the bottom electrode and the peripheral electrode is not required in the production of the electrode 305.

Hereinafter, another example of the second sensor that can be mounted on the measuring instrument 100 instead of the second sensors 105A to 105C will be described. 15 is a sectional view showing still another example of the second sensor.

The second sensor 405 shown in FIG. 15 has a plurality of electrodes 465. The plurality of electrodes 465 are provided on the base substrate 102 so as to extend in the thickness direction of the base substrate 102 from the upper surface of the base substrate 102. In the second sensor 405, the plurality of electrodes 465 provide a cross section 465a on the way between the upper surface and the bottom surface of the base substrate 102. [ The end face 465a of the plurality of electrodes 465 constitutes a bottom electrode and a plurality of peripheral electrodes similarly to the end face 365a of the plurality of electrodes 365 of the second sensor 305. [ In the measuring instrument 100 for mounting the second sensor 405, the base substrate 102 may be, for example, a glass substrate. Also in the fabrication of the second sensor 405, a step of separately forming the bottom electrode and the plurality of peripheral electrodes becomes unnecessary.

Hereinafter, another example of the second sensor that can be mounted on the measuring instrument 100 instead of the second sensors 105A to 105C will be described. 16 is a sectional view showing still another example of the second sensor.

The second sensor 505 shown in Fig. 16 has a plurality of electrodes 365 arranged in each of the region 361 and the peripheral regions 362a to 362d, like the second sensor 305. [ The second sensor 505 further includes surrounding electrodes 370a to 370e. The surrounding electrodes 370a to 370e are formed of a conductor and are insulated from the electrodes 365 in the second sensor 505. [ The surrounding electrode 370a is formed along the bottom surface of the base substrate to collectively surround the end face 365a of a group of electrodes 365 disposed in the peripheral region 362a. A via electrode 371a penetrating the base substrate is connected to the surrounding electrode 370a. The surrounding electrode 370b is formed along the bottom surface of the base substrate so as to collectively surround the end face 365a of the group of electrodes 365 disposed in the peripheral region 362b. A via electrode 371b penetrating the base substrate is connected to the surrounding electrode 370b. The surrounding electrode 370c is formed along the bottom surface of the base substrate so as to collectively surround the end face 365a of a group of electrodes 365 disposed in the peripheral region 362c. A via electrode 371c penetrating the base substrate is connected to the surrounding electrode 370c. The surrounding electrode 370d is formed along the bottom surface of the base substrate so as to collectively surround the end face 365a of a group of electrodes 365 disposed in the peripheral region 362d. A via electrode 371d penetrating the base substrate is connected to the surrounding electrode 370d. The surrounding electrode 370e is formed along the bottom surface of the base substrate so as to collectively surround the end face 365a of a group of electrodes 365 disposed in the region 361. [ A via electrode 371e penetrating the base substrate is connected to the surrounding electrode 370e. A high-frequency oscillator 171 is electrically connected to each of the via electrodes 371a to 371e, and a high-frequency signal is applied to each of the surrounding electrodes 370a to 370e. In the second sensor 505 an end face 365a of a group of electrodes 365 is surrounded by an encircling electrode 365a of a group of electrodes 365 of the surrounding electrodes 370a through 370e And is shielded against the outside of the surrounding electrode. Therefore, in the measurement of the capacitance, the directivity of the second sensor 505 is improved.

Various embodiments have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made. For example, although the plasma processing apparatus is exemplified as an example of the process modules PM1 to PM6, the process modules PM1 to PM6 may be any processing apparatus as far as the electrostatic chuck and the focus ring are used. Although the plasma processing apparatus 10 described above is a capacitively coupled plasma processing apparatus, the plasma processing apparatus that can be used as the process modules PM1 to PM6 includes an inductively coupled plasma processing apparatus, And may be any plasma processing apparatus, such as a plasma processing apparatus.

The positional relationship between the bottom electrode of the plurality of second sensors and the center axis AX100 of the measuring instrument 100 is determined by the positional relationship between the center axis of the table PD and the lift pins 25a But the positional relationship between the bottom electrode of the plurality of second sensors and the center axis AX100 of the measuring instrument 100 is not limited to this. For example, the distance between each of the bottom electrodes of the plurality of second sensors and the central axis AX100 of the measuring instrument 100 is approximately equal to the distance between the center axis of the placement stand PD and the edge of the electrostatic chuck .

Hereinafter, a measuring instrument according to another embodiment will be described. That is, a measuring instrument in which the distance between each of the bottom electrodes of the plurality of second sensors and the central axis AX100 of the measuring device substantially coincides with the distance between the center axis of the table PD and the edge of the electrostatic chuck do. In addition, a measuring instrument according to another embodiment of the present invention can also be used in the processing system shown in Fig. 17 is a plan view of the measuring instrument as seen from the bottom surface side. The measuring device 600 shown in Fig. 17 includes a base substrate 102. [ On the lower portion 102a of the base substrate 102, four first sensors 104A to 104D for measuring capacitance are provided. Four second sensors 605A to 605D are provided in the lower portion 102a of the base substrate 102 in place of the second sensors 105A to 105C shown in Fig. However, the number of the second sensors provided in the measuring device 600 may be any number of three or more. The second sensors 605A to 605D are arranged at regular intervals in the circumferential direction along a circle sharing the center axis AX100 of the base substrate 102. [ The second sensors 605A to 605D and the first sensors 104A to 104D are arranged alternately in the circumferential direction. Each of the four second sensors 605A to 605D has a bottom electrode 606 provided along the bottom surface of the base substrate 102. [

18 is a cross-sectional view of the electrostatic chuck, showing a state in which the workpiece is placed on the electrostatic chuck. In one embodiment, the electrostatic chuck ESC has a structure in which an electrode E serving as a conductive film is disposed between a pair of insulating layers or insulating sheets, and has a substantially disk shape. The electrostatic chuck ESC has a placement area R where the workpiece W and the measuring device 600 are placed thereon. The placement area R has a circular edge. The workpiece W and the measuring instrument 600 have an outer diameter larger than the outer diameter of the placement area R. [

Fig. 19 is a partially enlarged view of Fig. 17, showing one second sensor. The edge of the bottom electrode 606 has a partially circular arc shape. That is, the bottom electrode 606 has a planar shape defined by two arcs 606a and 606b having different radii centered on the central axis AX100. The radially outward arc 606b of the bottom electrode 606 of each of the plurality of second sensors 605A through 605D extends over a common circle. In addition, the radially inner arc 606a of the bottom electrode 606 of each of the plurality of second sensors 605A to 605D extends over another common circle. The curvature of a part of the edge of the bottom electrode 606 coincides with the curvature of the edge of the electrostatic chuck ESC (placement area R). The curvature of the arc 606b forming the edge in the radially outward side of the bottom electrode 606 coincides with the curvature of the edge of the placement area R of the electrostatic chuck ESC. In addition, the center of curvature of the arc 606b, that is, the center of the circle where the arc 606b extends above it, shares the central axis AX100.

In one embodiment, each of the second sensors 605A-605D further includes an electrode 607 that surrounds the bottom electrode 606. The electrode 607 has a frame-like shape and surrounds the bottom electrode 606 over its entire periphery. The electrode 607 and the bottom electrode 606 are separated from each other such that an insulating region 608 is interposed therebetween. In one embodiment, each of the second sensors 605A to 605D further includes an electrode 609 surrounding the electrode 607 outside the electrode 607. The electrode 609 has a frame shape and surrounds the electrode 607 over its entire periphery. The electrode 607 and the electrode 609 are separated from each other such that an insulating region 610 is interposed therebetween.

20 is a diagram illustrating the configuration of a circuit board of the measuring instrument. The measuring instrument 600 has a circuit board 106A. The circuit board 106A corresponds to the circuit board 106 in the measuring instrument 100. [ 20, the circuit board 106A includes a high-frequency oscillator 171, a plurality of C / V conversion circuits 172A to 172D, a plurality of C / V conversion circuits 680A to 680D, an A / A memory 173, a processor 174, a storage device 175, a communication device 176, a power source 177, and a storage device 178.

The bottom electrode 606 of the second sensors 605A to 605D is connected to the corresponding C / V conversion circuit among the C / V conversion circuits 680A to 680D through the corresponding wiring 681. [ Each of the electrodes 607 of the second sensors 605A to 605D is connected to a corresponding C / V conversion circuit among the C / V conversion circuits 680A to 680D through a corresponding wiring 682 . The bottom electrode 606 and the electrode 607 of each of the second sensors 605A to 605D are electrically connected to the high frequency oscillator 171 so that a high frequency signal from the high frequency oscillator 171 is given to them . Each of the C / V conversion circuits 680A to 680D is configured to generate, from the voltage amplitude at its input, a voltage signal indicating the capacitance of the electrode connected to the input, and output the voltage signal. Each of the electrodes 609 of the second sensors 605A to 605D is connected to the ground potential line GL through the corresponding wiring 683. [ The wiring 683 may be connected to the ground potential line GL via the switch SWG.

To the input of the A / D converter 173, the outputs of the plurality of C / V converting circuits 680A to 680D are connected. As a result, the A / D converter 173 generates a digital value (measured value) representing the capacitance of the bottom electrode 606. The A / D converter 173 outputs the generated digital value to the processor 174.

Hereinafter, a method of calibrating the conveying position data in the processing system 1 using the measuring device 600 will be described. In addition, as described above, the transport apparatus TU2 in the processing system 1 is controlled by the control unit MC. The transport apparatus TU2 transports the workpiece W and the measuring instrument 600 onto the placement area R of the electrostatic chuck ESC based on the transport position data transmitted from the control unit MC can do. 21 is a flowchart showing a calibration method of a transport apparatus in the processing system according to the embodiment.

In the method (MT) shown in FIG. 21, first, the process ST1 is executed. In step ST1, the measuring device 600 is carried by the carrying device TU2 to a position on the placement area R specified by the carrying position data. More specifically, the transport apparatus TU1 transports the measuring instrument 600 to one of the load lock module LL1 and the load lock module LL2. The transport apparatus TU2 transports the measuring instrument 600 to one of the process modules PM1 to PM6 from one of the load lock modules based on the transport position data, (R) of the ESC (ESC). The carry position data is coordinate data predetermined so that the position of the central axis AX100 of the measuring device 600 coincides with the center position of the placement area R, for example.

In subsequent step ST2, the measuring instrument 600 measures the electrostatic capacitance. More specifically, the measuring instrument 600 is provided with a plurality of sensors (not shown) corresponding to the magnitude of the electrostatic capacitance between the placement area R of the electrostatic chuck ESC and the bottom electrode 606 of each of the second sensors 605A to 605D Acquires a digital value (measured value), and stores the plurality of digital values in the storage device 175. [ Further, the plurality of digital values can be acquired at a predetermined timing under the control of the processor 174. [ In one embodiment, the capacitance measurement by the first sensors 104A to 104D may be performed at the timing of measurement of the capacitance by the second sensors 605A to 605D.

In the succeeding step ST3, the measuring instrument 600 is taken out of the process module and returned to either the transfer module TF, the load lock modules LL1 and LL2, the loader module LM and the containers 4a to 4d. In the succeeding step ST4, an error between the position on the placement area R where the measuring instrument 600 is carried and the predetermined delivery position on the placement area R is derived. However, the predetermined transport position may be the center position of the placement area R. In step ST4 of the embodiment, first, a plurality of digital values stored in the storage device 175 are transmitted to the control unit MC. The plurality of digital values may be transmitted from the communication device 176 to the control unit MC by a command from the control unit MC or may be transmitted to the control unit MC by the control of the processor 174 based on the count of the timer provided in the circuit board 106A Or may be transmitted to the control unit MC at a predetermined timing. Subsequently, an error of the conveyance position of the measuring instrument 600 is derived based on the plurality of digital values received by the control unit MC. In one embodiment, the control unit MC has a data table showing the relationship between the transport position of the measuring instrument 600 on the placement area R and the digital value acquired by the second sensors 605A to 605D. In this data table, for example, the relationship between the position of the bottom electrode 606 in each radial direction of the placement region R and the digital value indicating the electrostatic capacity of the bottom electrode 606 at that position is It is registered.

22 is a diagram showing the carrying position of the measuring instrument with respect to the placement area of the electrostatic chuck. 22A shows the positional relationship between the placement area R and one bottom electrode 606 when the measuring instrument 600 is transported to a predetermined transporting position. 22B and 22C show the positional relationship between the placement region R and one bottom electrode 606 when the measuring instrument 600 is shifted from the predetermined carrying position. 22 (b), when the bottom electrode 606 is shifted to the outside in the radial direction of the placement region R with respect to the placement region R, the electrostatic force measured by the bottom electrode 606 The capacitance is smaller than the capacitance when the measuring instrument 600 is transported to a predetermined transport position (Fig. 22 (a)). 22 (c), when the bottom electrode 606 is displaced inward in the radial direction of the placement region R with respect to the placement region R, due to the influence of the electrode E, The electrostatic capacitance measured by the electrode 606 is larger than the electrostatic capacitance measured when the measuring instrument 600 is transported to a predetermined transport position (FIG. 22 (a)). Therefore, by referring to the data table using the digital values representing the capacitances of the respective bottom electrodes 606 of the second sensors 605A to 605D, The displacement amount of the electrode 606 can be obtained. An error of the conveying position of the measuring instrument 600 can be obtained from the amount of displacement of the bottom electrode 606 of each of the second sensors 605A to 605D in the radial direction.

When the error of the conveying position of the measuring instrument 600 is larger than the predetermined threshold value, it is determined that the conveying position data needs to be calibrated in subsequent step ST5. In this case, the transporting position data is corrected by the control unit MC so as to eliminate the error in the step ST6. Then, in step ST7, the measuring instrument 600 is again transported to the same process module as that of the process module in which the measuring instrument 600 was transported, and steps ST2 to ST5 are executed again. On the other hand, when the error of the conveying position of the measuring instrument 600 is smaller than the predetermined threshold value, it is determined that the conveying position data is not necessary to be calibrated in step ST5. In this case, in step ST8, it is determined whether or not to carry the measuring instrument 600 to another process module to which the measuring instrument 600 is to be conveyed next. Next, in the case where another process module to be conveyed by the measuring instrument 600 remains, the measuring device 600 is carried to the other process module in the succeeding step ST9, and the steps ST2 to ST5 are executed. On the other hand, if the measuring device 600 does not leave any other process modules to be returned, the method MT is terminated.

According to the method MT using the measuring device 600 as described above, a plurality of digital values usable in the calibration of the conveying position data used for conveying by the conveying device TU2 are provided by the measuring device 600. [ By using such a plurality of digital values, it becomes possible to calibrate the carrier position data as necessary. The workpiece W can be transported to a predetermined transporting position by using the transporting position data thus corrected for transporting the workpiece W by the transporting device TU2.

In one embodiment, the respective bottom electrodes 606 of the second sensors 605A to 605D are arranged along a circle that shares the central axis AX100 of the base substrate 102. [ When the measuring instrument 600 is transported so that the center axis AX100 of the base substrate 102 coincides with the center of the placement area R which is a predetermined transport position, the bottom electrodes of the second sensors 605A to 605D The digital value representing the electrostatic capacity of the capacitor 606 is ideally the same. Therefore, an error of the conveying position of the measuring device 600 can be easily obtained.

A part of the edge of each of the bottom electrodes 606 of the second sensors 605A to 605D has an arc shape and extends on a circle having a diameter substantially equal to the diameter of the placement area R . The curvature of a part of the edge of the bottom electrode 606 coincides with the curvature of the edge of the placement area R. [ Therefore, it is possible to measure the displacement amount in each radial direction between the conveying position of the measuring instrument 600 and the predetermined conveying position with good precision.

Claims (8)

A measuring instrument for measuring capacitance,
A base substrate having a disc shape,
A plurality of first sensors each providing a plurality of side electrodes arranged along an edge of the base substrate,
At least one second sensor each having a bottom electrode provided along a bottom surface of the base substrate,
A circuit board mounted on the base substrate and connected to each of the plurality of first sensors and the at least one second sensor, the circuit board including: a plurality of side electrodes and a bottom electrode; To generate a plurality of first measured values indicative of the capacitance from each of the voltage amplitudes at the side electrodes of the bottom electrode and to generate a second measured value representative of the capacitance from the voltage amplitude at the bottom electrode, And a substrate. The method according to claim 1,
Each of the bottom electrodes of the at least one second sensor has a circular shape,
Each of the one or more second sensors further includes a peripheral electrode arranged to surround the bottom electrode,
Wherein the circuit board is further configured to apply the high-frequency signal to the peripheral electrode to generate a third measured value indicating the capacitance from the voltage amplitude at the peripheral electrode. The method according to claim 1 or 2,
Wherein the at least one second sensor is a plurality of second sensors,
And the plurality of second sensors are disposed along a circle that shares a center axis of the base substrate. The method according to any one of claims 1 to 3,
Each of the at least one second sensor further includes a plurality of electrodes provided on the base substrate so as to extend from the upper surface of the base substrate in the thickness direction of the base substrate,
Wherein the bottom electrode of each of the at least one second sensor is formed by a cross-section of the bottom surface of the plurality of electrodes. The method according to any one of claims 1 to 3,
Each of the one or more second sensors further includes at least one penetrating electrode penetrating the base substrate,
Wherein each of the bottom electrodes of the at least one second sensor is connected to the circuit board through the at least one through electrode. The method according to claim 1,
Wherein the at least one second sensor is at least three second sensors,
Wherein each of the at least three second sensors has a bottom electrode provided along a bottom surface of the base substrate and is disposed along a circle sharing a central axis of the base substrate,
Wherein a part of an edge of each of said bottom electrodes of said at least three second sensors has an arc shape and extends on said circle. A method for calibrating transfer position data in a processing system using the measuring instrument according to claim 6,
The processing system comprising:
A processing apparatus having a chamber body and a chamber provided by the chamber body and having a placement area having a circular edge and having an electrostatic chuck on which a workpiece is placed on the placement area;
And a transfer device for transferring the workpiece on the placement area based on the transfer position data,
Transporting the measuring instrument using the transporting device at a position on the placement area specified by the transporting position data;
A step of measuring three or more electrostatic capacitances by the three or more second sensors of the measuring instrument conveyed on the placement area,
A step of obtaining an error with respect to a predetermined transporting position on the mountable area at a position on the mountable area where the measuring instrument is transported from the measured values of the three or more capacitances,
And correcting the transfer position data using the error. The method of claim 7,
Wherein the curvature of the portion of the edge of the bottom electrode coincides with the curvature of the edge of the placement area.

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