Substrate processing system and substrate inspection device

Abstract

To provide technology for correcting a substrate image.SOLUTION: In one exemplary embodiment, a substrate processing system is provided. The substrate processing system comprises an atmospheric air transfer module, a load lock module, a vacuum transfer module, a plasma processing module, a load port, and a substrate inspection module. The substrate inspection module is connected to the atmospheric transfer module downward of the load port. The substrate inspection module includes a housing, a substrate holding unit, a drive unit, a light irradiation unit, an imaging unit, a light direction conversion unit, a first reflector, a second reflector, and a control unit. The first and the second reflectors have a higher reflective index than a reflective index of light of the housing in the surrounding of these.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] Exemplary embodiments of the present disclosure relate to a substrate processing system and a substrate inspection apparatus. [Background technology]

[0002] A substrate processing system is used for processing a substrate. The substrate processing system includes an atmospheric transfer module, a load lock module, a vacuum transfer module, a plasma processing module, a load port, and a substrate inspection module. In Patent Document 1 below, the substrate inspection module has an imaging unit and a control unit. The imaging unit includes a line sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-146404 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides techniques for correcting an image of a substrate. [Means for solving the problem]

[0005] In one exemplary embodiment, a substrate processing system is provided. The substrate processing system includes an atmospheric transfer module, a load lock module, a vacuum transfer module, a plasma processing module, a load port, and a substrate inspection module. The load lock module is connected to the atmospheric transfer module. The vacuum transfer module is connected to the load lock module. The plasma processing module is connected to the vacuum transfer module. The load port is connected to the atmospheric transfer module. The substrate inspection module is connected to the atmospheric transfer module below the load port. The substrate inspection module includes a housing, a substrate holding unit, a drive unit, a light irradiation unit, an imaging unit, a light direction change unit, a first reflector, a second reflector, and a control unit. The substrate holding unit is disposed within the housing. The drive unit is configured to move the substrate holding unit along a transport path within the housing. The imaging unit includes a line sensor. The light direction change unit is configured to change the direction of the received light. The light direction change unit is disposed above the transport path. The light direction conversion unit is configured to irradiate the light emitted from the light irradiation unit onto the substrate held by the substrate holding unit and moved along the transport path, and to guide the light reflected by the substrate to the imaging unit. The first reflecting material and the second reflecting material are disposed below the light direction conversion unit. The first reflecting material and the second reflecting material are disposed on both sides of the transport path in a direction intersecting or perpendicular to the transport path. The control unit is configured to correct the image of the substrate. The image of the substrate is composed of a plurality of line images. The plurality of line images are based on an output from a line sensor. The first reflecting material and the second reflecting material have a reflectance higher than the reflectance of light of the housing around them. The control unit is configured to correct the pixel values ​​of the plurality of pixels in each of the plurality of line images using a difference between an average value of the pixel value of the first pixel and the pixel value of the second pixel and a reference value. The pixel value of the first pixel is a pixel value according to the intensity of light from the first reflecting material in each of the plurality of line images. The pixel value of the second pixel is a pixel value that corresponds to the intensity of light from the second reflecting material in each of the multiple line images. Effect of the Invention

[0006] According to one exemplary embodiment, a technique is provided for correcting an image of a substrate. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 illustrates a substrate processing system according to an exemplary embodiment. [Diagram 2] 1 is a side view of a substrate processing system according to an exemplary embodiment. [Diagram 3] FIG. 1 is a diagram for explaining a configuration example of a plasma processing system. [Figure 4] FIG. 1 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus. [Diagram 5] 1 is a cross-sectional view of a substrate inspection module according to an exemplary embodiment; [Figure 6] 2 is another cross-sectional view of a substrate inspection module according to an exemplary embodiment; FIG. [Figure 7] 1 is yet another cross-sectional view of a substrate inspection module in accordance with an exemplary embodiment; [Figure 8] FIG. 2 illustrates an image of a substrate according to an exemplary embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Various exemplary embodiments will now be described in detail with reference to the drawings, in which the same or corresponding parts are designated by the same reference numerals.

[0009] FIG. 1 is a diagram showing a substrate processing system according to an exemplary embodiment. FIG. 2 is a side view of the substrate processing system according to an exemplary embodiment. As shown in FIG. 1, the substrate processing system PS includes a loader module LM, load lock modules LL1 and LL2, at least one transfer module, at least one process module, load ports LP1 to LP4, and a substrate inspection module CM. The loader module LM is an example of an atmospheric transfer module. The at least one transfer module is an example of a vacuum transfer module. The substrate inspection module CM is an example of a substrate inspection device. The substrate processing system PS may include a plurality of transfer modules TM1 and TM2 as the at least one transfer module. The at least one process module is an example of a plasma processing module. The substrate processing system PS may include a plurality of process modules PM1 to PM12 as the at least one process module. The substrate processing system PS may further include an aligner AN, a storage SR, and a controller CU.

[0010] The loader module LM includes a chamber. The pressure in the chamber of the loader module LM is set to atmospheric pressure. The loader module LM may have an FFU (Fan Filter Unit). The loader module LM is, for example, an EFEM (Equipment Front End Module). The loader module LM is disposed between each of the load ports LP1 to LP4 and each of the load lock modules LL1 and LL2. The load ports LP1 to LP4 are arranged along one of a pair of edges along the longitudinal direction of the loader module LM. The load lock modules LL1 and LL2 are arranged along the other of a pair of edges along the longitudinal direction of the loader module LM. Each of the load ports LP1 to LP4 is configured to support a cassette CST placed thereon. The cassette CST is a container that accommodates a plurality of substrates W therein. The cassette CST is, for example, a FOUP (Front-Opening Unified Pod).

[0011] The loader module LM may include a transport robot TR3. The transport robot TR3 is provided in a chamber of the loader module LM. The transport robot TR3 may include a multi-joint arm AR31 and a pick FK31. The pick FK31 is attached to the tip of the multi-joint arm AR31 and configured to support a substrate W placed thereon. The transport robot TR3 transports the substrate W based on an operation instruction output by a control unit CU, which will be described later. The transport robot TR3 transports the substrate W between any two of a cassette CST, a load lock module LL1, LL2, an aligner AN, and a storage SR, which are placed on at least one of the load ports LP1 to LP4.

[0012] The aligner AN is disposed along one of a pair of edges along the short side direction of the loader module LM. The aligner AN may be disposed along an edge along the long side direction of the loader module LM. The aligner AN may also be disposed in a chamber of the loader module LM. The aligner AN has a support base, an optical sensor, and the like. The support base of the aligner AN is rotatable and supports the substrate W placed thereon. The aligner AN detects the angular position of a marker (e.g., a notch) of the substrate W on the support base and the center position of the substrate W on the support base using an optical sensor. The control unit CU controls the rotation of the support base of the aligner AN so as to correct the angular position of the marker (e.g., a notch) of the substrate W on the support base to a reference angular position so as to correct the amount of deviation of the angular position of the substrate W. The control unit CU also controls the position of the pick FK31 when receiving the substrate W from the aligner AN onto the pick FK31 in order to position the center of the substrate W on a predetermined position of the pick FK31.

[0013] The storage SR is disposed along an edge along the longitudinal direction of the loader module LM. The storage SR may be disposed along an edge along the lateral direction of the loader module LM. The storage SR may also be provided inside the loader module LM. The storage SR is configured to accommodate the substrate W therein.

[0014] 1 and 2, the substrate inspection module CM is connected to the loader module LM below the load ports LP1 to LP4. The substrate inspection module CM is configured to acquire an image of the substrate W. Details of the substrate inspection module CM will be described later.

[0015] The load lock modules LL1 and LL2 are connected to the loader module LM. In the example shown in FIG. 1, each of the load lock modules LL1 and LL2 and the transfer module TM1 are connected via a gate valve G2. Each of the load lock modules LL1 and LL2 may be disposed between the transfer module TM1 and the loader module LM. Each of the load lock modules LL1 and LL2 provides a preliminary decompression chamber. Each of the load lock modules LL1 and LL2 and the loader module LM may be connected via a gate valve G3.

[0016] The transfer modules TM1 and TM2 are connected to the load lock modules LL1 and LL2. Each of the transfer modules TM1 and TM2 may include a chamber. In the example shown in Fig. 1, each of the transfer modules TM1 and TM2 is configured to transfer the substrate W through a reduced pressure space in the chamber. The chamber of the transfer module TM1 may be connected to each of the load lock modules LL1 and LL2 through a gate valve G2.

[0017] The process modules PM1 to PM6 are connected to the transfer modules TM1 and TM2. The process modules PM1 to PM6 may be connected to the chamber of the transfer module TM1 via a gate valve G1. The chamber of the transfer module TM1 is connected to the chamber of the transfer module TM2. The process modules PM7 to PM12 may be connected to the chamber of the transfer module TM2 via a gate valve G1.

[0018] In one embodiment, the transfer module TM1 may include a transfer robot TR1 provided in its chamber. The transfer robot TR1 may include articulated arms AR11, AR12 and picks FK11, FK12. The pick FK11 is attached to the tip of the articulated arm AR11 and configured to support the substrate W placed thereon. The pick FK12 is attached to the tip of the articulated arm AR12 and configured to support the substrate W placed thereon. The transfer robot TR1 transfers the substrate W based on an operation instruction output by a control unit CU, which will be described later. The transfer robot TR1 holds the substrate W by the picks FK11, FK12. The transfer robot TR1 transfers the substrate W between any two of the load lock modules LL1, LL2, the process modules PM1 to PM6, the chamber of the transfer module TM1, and the path between the chamber of the transfer module TM1 and the chamber of the transfer module TM2.

[0019] In one embodiment, the transfer module TM2 includes a transfer robot TR2 provided in its chamber. The transfer robot TR2 may include articulated arms AR21, AR22 and picks FK21, FK22. The pick FK21 is attached to the tip of the articulated arm AR21 and configured to support the substrate W placed thereon. The pick FK22 is attached to the tip of the articulated arm AR22 and configured to support the substrate W placed thereon. The transfer robot TR2 transfers the substrate W based on an operation instruction output by a control unit CU, which will be described later. The transfer robot TR2 holds the substrate W by the picks FK21, FK22. The transfer robot TR2 transfers the substrate W between any two of the path between the chamber of the transfer module TM1 and the chamber of the transfer module TM2, the process modules PM7 to PM12, and the chamber of the transfer module TM2.

[0020] In one embodiment, each of the process modules PM1 to PM12 is configured to perform a dedicated process on the substrate W. At least one of the process modules PM1 to PM12 is a substrate processing system such as a plasma processing apparatus 1 described below.

[0021] The control unit CU is, for example, a computer. The control unit CU may be composed of a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or the auxiliary storage device, and controls each part of the substrate processing system PS.

[0022] The substrate processing system PS is not necessarily limited to that shown in FIG. 1. For example, the number of process modules and / or the number of transfer modules in the substrate processing system may be different from that shown in FIG. 1. For example, the number of load ports may be five or more, and the number of load ports may be any number. The substrate processing system may be a system in which a plurality of module groups, each including a process module and a load lock module, are connected to a loader module (a so-called loader type system). The substrate processing system may be a system in which two or more process modules are connected in a line around a transfer module so as to surround the transfer module (a so-called cluster type system).

[0023] 3 and 4 will be referred to below. The plasma processing system shown in Fig. 3 can be employed as a part of a substrate processing system PS. An example of a plasma processing apparatus shown in Fig. 4 is employed as at least one of the process modules PM1 to PM12.

[0024] FIG. 3 is a diagram for explaining a configuration example of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing device 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing device 1 is an example of a substrate processing device. The plasma processing device 1 includes a plasma processing chamber 10, a substrate support unit 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space, and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 described later, and the gas exhaust port is connected to an exhaust system 40 described later. The substrate support unit 11 is disposed in the plasma processing space, and has a substrate support surface for supporting a substrate.

[0025] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an electron-cyclotron-resonance plasma (ECR plasma), a helicon wave plasma (HWP), a surface wave plasma (SWP), or the like. Also, various types of plasma generating units may be used, including an alternating current (AC) plasma generating unit and a direct current (DC) plasma generating unit. In one embodiment, the AC signal (AC power) used in the AC plasma generating unit has a frequency in the range of 100 kHz to 10 GHz. Thus, the AC signal includes a radio frequency (RF) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0026] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to execute various steps described in the present disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to execute various steps described herein. In one embodiment, a part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 is realized, for example, by a computer 2a. The processing unit 2a1 may be configured to perform various control operations by reading a program from the storage unit 2a2 and executing the read program. This program may be stored in the storage unit 2a2 in advance, or may be acquired via a medium when necessary. The acquired program is stored in the storage unit 2a2 and is read from the storage unit 2a2 by the processing unit 2a1 and executed. The medium may be various storage media readable by the computer 2a, or may be a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The storage unit 2a2 may include a random access memory (RAM), a read only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination of these. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN). The control unit 2 may also function as a control unit CU.

[0027] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 4 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0028] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed in the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a part of a ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from a housing of the plasma processing chamber 10.

[0029] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting the substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of the substrate W. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0030] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 may function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may have the annular region 111b. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Also, at least one RF / DC electrode coupled to an RF power source 31 and / or a DC power source 32 described later may be disposed in the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal described later is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Also, the electrostatic electrode 1111b may function as a lower electrode. Thus, the substrate support 11 includes at least one lower electrode.

[0031] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0032] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow passage 1110a, or a combination thereof. A heat transfer fluid such as a brine or a gas flows through the flow passage 1110a. In one embodiment, the flow passage 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the central region 111a.

[0033] The shower head 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The shower head 13 also includes at least one upper electrode. Note that the gas introduction unit may include, in addition to the shower head 13, one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0034] The gas supply 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply 20 is configured to supply at least one process gas from a respective gas source 21 through a respective flow controller 22 to the showerhead 13. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply 20 may include at least one flow modulation device to modulate or pulse a flow rate of the at least one process gas.

[0035] The power source 30 includes an RF power source 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power source 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This causes a plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power source 31 can function as at least a part of the plasma generating unit 12. In addition, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, and ion components in the formed plasma can be attracted to the substrate W.

[0036] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit, and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate a plurality of source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0037] The second RF generating unit 31b is coupled to at least one lower electrode via at least one impedance matching circuit and configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generating unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. Also, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0038] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0039] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular or combination of these pulse waveforms. In one embodiment, a waveform generator for generating a sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have a positive polarity or a negative polarity. Also, the sequence of voltage pulses may include one or more positive polarity voltage pulses and one or more negative polarity voltage pulses in one period. The first and second DC generating units 32a, 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided in place of the second RF generating unit 31b.

[0040] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is adjusted by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0041] Reference will now be made to Figs. 5 to 7. Fig. 5 is a cross-sectional view of a substrate inspection module according to an exemplary embodiment. Fig. 6 is another cross-sectional view of a substrate inspection module according to an exemplary embodiment. Fig. 7 is yet another cross-sectional view of a substrate inspection module according to an exemplary embodiment. Fig. 5 shows the structure of the substrate inspection module CM in a cross section perpendicular to a first direction. The first direction is a direction perpendicular to the vertical direction and a transport path P described later. Fig. 6 shows the structure of the substrate inspection module CM in a cross section perpendicular to the vertical direction. Fig. 7 shows the structure of the substrate inspection module CM in a cross section perpendicular to a second direction. The second direction is a direction along a transport path P described later.

[0042] The board inspection module CM includes a housing 5, a board holding unit 61, a driving unit 63, a light irradiation unit 70, an imaging unit 8, a light direction conversion unit 7, a first reflecting plate 91, a second reflecting plate 92, and a control unit. In the example shown in Fig. 5 and Fig. 6, the control unit of the board inspection module CM is also functioned as the control unit. The first reflecting plate 91 is an example of a first reflecting material. The second reflecting plate 92 is an example of a second reflecting material.

[0043] The housing 5 provides a space therein. The substrate holding unit 61, the first reflecting plate 91, and the second reflecting plate 92 are disposed in the housing 5. In the example shown in Figs. 5 to 7, the driving unit 63, the light emitting unit 70, the imaging unit 8, and the light direction conversion unit 7 are further disposed in the housing 5. The housing 5 may have a substantially rectangular parallelepiped shape. The housing 5 may include a pair of side walls 5a, 5b facing each other in the first direction (or the lateral direction). The housing 5 may include a door 51. The door 51 opens and closes an opening of the housing 5 that communicates with the space inside the housing 5. The substrate W is transported in and out of the housing 5 through the door 51. In one example, the housing 5 is formed of a steel plate having a zinc-plated surface.

[0044] The substrate holding part 61 is configured to hold a substrate W placed thereon. In one example, the substrate holding part 61 includes a flat upper surface. A suction port is formed in the upper surface. The substrate W is held on the substrate holding part 61 by being sucked into the suction port. The substrate holding part 61 may include a rotating part 62. The rotating part 62 is configured to rotate the substrate holding part 61 and the substrate W on the substrate holding part 61 about their central axes. The central axis of the substrate holding part 61 extends along the vertical direction.

[0045] The drive unit 63 is configured to move the substrate holding unit 61 along the transport path P in the housing 5. The substrate W held on the substrate holding unit 61 is moved along the transport path P together with the substrate holding unit 61. The transport path P extends along the second direction (or movement direction) described above. In the example shown in FIGS. 5 to 7, the drive unit 63 moves the substrate holding unit 61 from a first position to a second position in the housing 5. The second position is farther from the door 51 than the first position.

[0046] In one embodiment, the substrate inspection module CM further includes a position detection sensor 64. The position detection sensor 64 detects the position of the peripheral edge of the substrate W held on the substrate holding portion 61. The position detection sensor 64 may detect the eccentricity of the central position of the substrate W relative to the central position of the substrate holding portion 61. The position detection sensor 64 may detect the position of a notch of the substrate W.

[0047] The imaging unit 8 includes a line sensor. The line sensor is composed of a plurality of sensor elements arranged in one direction. In one example, the plurality of sensor elements may include a light receiving element and a preamplifier. The line sensor is also called a line sensor camera or a line scan camera. The direction in which the line sensor extends is parallel to the first direction and may be perpendicular to the transport path P. In the substrate inspection module CM, the substrate W is moved along the movement direction by the driving unit 63, while a plurality of line images are acquired by the line sensor. The plurality of line images constitute an image of the substrate W.

[0048] The light direction conversion unit 7 is configured to change the direction of the received light. The light direction conversion unit 7 is disposed above the transport path P. The light direction conversion unit 7 is configured to irradiate the light emitted from the light irradiation unit 70 onto the substrate W held by the substrate holding unit 61 and moved along the transport path P, and to guide the light reflected by the substrate W to the imaging unit 8. In one example, the imaging unit 8 captures a plurality of line images from one end to the other end of the substrate W on the transport path P.

[0049] As shown in FIG. 5, the light direction conversion unit 7 may include a light irradiation unit 70, a first reflecting mirror 71, a second reflecting mirror 72, and a third reflecting mirror 73. The light irradiation unit 70 is configured to emit light to be irradiated onto the substrate W. The light emission direction of the light irradiation unit 70 may be a downward direction. The first reflecting mirror 71 is disposed below the light irradiation unit 70 and is optically coupled to the light irradiation unit 70 and the second reflecting mirror 72. In one example, the first reflecting mirror 71 is a half mirror. In this example, the first reflecting mirror 71 transmits light from the light irradiation unit 70 downward and reflects the light reflected from the substrate W to change the traveling direction of the light to a second direction. The second reflecting mirror 72 is disposed to face the first reflecting mirror 71 in the second direction and is optically coupled to the first reflecting mirror 71 and the third reflecting mirror 73. The second reflecting mirror 72 changes the traveling direction of the light from the first reflecting mirror 71 to an obliquely upward direction. The third reflecting mirror 73 is disposed to face the imaging unit 8 in the second direction, and is optically coupled to the second reflecting mirror 72 and the imaging unit 8. The third reflecting mirror 73 changes the traveling direction of the light from the second reflecting mirror 72 to the second direction, and couples the light from the second reflecting mirror 72 to the imaging unit 8.

[0050] The light emitted from the light irradiation unit 70 passes through the first reflecting mirror 71 and is irradiated onto the substrate W. The light irradiated onto the substrate W is reflected by the substrate W so as to head towards the first reflecting mirror 71. The light that reaches the first reflecting mirror 71 from the substrate W is reflected by the first reflecting mirror 71 so as to head towards the second reflecting mirror 72. The light that reaches the second reflecting mirror 72 from the first reflecting mirror 71 is reflected by the second reflecting mirror 72 so as to head towards the third reflecting mirror 73. The light that reaches the third reflecting mirror 73 from the second reflecting mirror 72 is reflected by the third reflecting mirror 73 so as to head towards the imaging unit 8.

[0051] The first reflecting plate 91 and the second reflecting plate 92 are disposed below the light direction changing unit 7, specifically below the first reflecting mirror 71. The first reflecting plate 91 and the second reflecting plate 92 are disposed on both sides of the transport path P in the second direction, that is, in the direction intersecting or perpendicular to the transport path P. In the example shown in FIG. 5 to FIG. 7, the first reflecting plate 91 is disposed along the side wall 5a, and the second reflecting plate 92 is disposed along the side wall 5b. As shown in FIG. 7, the first reflecting plate 91 includes a light reflecting surface 91a, and the second reflecting plate 92 includes a light reflecting surface 92a. The first reflecting plate 91 and the second reflecting plate 92 are configured to reflect light irradiated to the light reflecting surfaces 91a and 92a toward the light irradiating unit 70 (or the first reflecting mirror 71). The reflectance of each of the first reflector 91 and the second reflector 92 (the reflectance of each of the light reflecting surfaces 91a, 92a) to light is higher than the reflectance of the housing 5 around the first reflector 91 and the second reflector 92 to light. The reflectance of each of the light reflecting surfaces 91a, 92a may be 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more. In one example, the first reflector 91 and the second reflector 92 are made of silicon, aluminum, or stainless steel. The first reflector 91 and the second reflector 92 may be mirror-finished.

[0052] In one embodiment, the first normal direction of the light reflecting surface 91a of the first reflecting plate 91 and the second normal direction of the light reflecting surface 92a of the second reflecting plate 92 are inclined so that the first normal direction and the second normal direction intersect with each other, as shown in FIG. 7. The first reflecting plate 91 and the second reflecting plate 92 may be arranged so that the first normal direction and the second normal direction intersect with each other. In one embodiment, the substrate inspection module CM may include an adjustment unit 93 configured to adjust the inclination of the first reflecting plate 91 and the second reflecting plate 92, respectively, so as to adjust the angle at which the first normal direction and the second normal direction intersect with each other. The adjustment unit 93 may include at least one actuator for adjusting the inclination of the first reflecting plate 91 and the second reflecting plate 92, respectively.

[0053] Reference is now made to FIG. 8. FIG. 8 is a diagram showing an image of a substrate according to an exemplary embodiment. The control unit CU is configured to correct the image WP of the substrate W. As shown in FIG. 8, the image WP of the substrate W is composed of a plurality of line images LP. In the example shown in FIG. 8, the plurality of line images LP includes an n-th line image Ln (n can be selected from any integer equal to or greater than 2). The plurality of line images LP are based on the output from the line sensor of the imaging unit 8. The output of the line sensor is based on the intensity of light from the light direction conversion unit 7. Each of the plurality of line images LP is composed of a plurality of pixels linearly aligned to correspond to a plurality of sensor elements of the line sensor. Each of the plurality of pixels in each of the plurality of line images LP has a pixel value corresponding to the intensity (illuminance) of light reaching the corresponding sensor element via the light direction conversion unit 7 from a corresponding reflector among the first reflector 91, the substrate W, the inner surface of the housing 5, or the second reflector 92.

[0054] In one embodiment, the control unit CU is configured to apply a first correction to each of the multiple line images LP. The first correction includes an offset correction and a blank correction. In the offset correction, noise due to dark current of each of the multiple sensor elements of the line sensor is corrected. In the blank correction, a variation in gain (ratio of input to output) in each of the multiple sensor elements of the line sensor is corrected.

[0055] The pixel values ​​x of the pixels of each of the line images LP ij and the pixel value y after the first correction is applied. ij The relationship between the pixel value x and the pixel value x is expressed by the following equation (1). ij is the pixel value of the i-th pixel among the pixels linearly aligned in the j-th line image among the line images LP. ij is the pixel value x ij is the value obtained by applying the first correction to

number

[0056] The pixel value x ij The intensity of the light irradiated to the corresponding sensor element when the pixel value x ij (output value). In equation (1), g is a gain common to multiple sensor elements. According to the calculation of equation (1), the variation in the gain of the sensor element with respect to the input value is corrected by multiplying g by the fractional term. Note that the fractional term in equation (1) is the pixel value x ij The relationship between the input value and the input value is approximated by a quadratic equation. In equation (1), the coefficient c i is a correction coefficient for offset correction at the i-th pixel among the multiple pixels of the line image. In one example, the coefficient c i is obtained from the pixel value of a pixel obtained from a corresponding sensor element among the multiple sensor elements of the image capturing unit 8 when the image capturing unit 8 is shielded from light. i ,b iis a correction coefficient for blank correction at the i-th pixel among the multiple pixels of the line image. In one example, the coefficient a i ,b i is determined in advance from a plurality of pixel values ​​obtained by changing the intensity of light irradiated onto the corresponding sensor element.

[0057] In one embodiment, the control unit CU is configured to apply a second correction to each of the plurality of line images obtained by applying the first correction to the plurality of line images LP. The second correction includes a reference correction. In the following description, the plurality of line images obtained by applying the first correction to the plurality of line images LP are represented as a plurality of line images LP. Thus, in the following description, a pixel in the plurality of line images LP is represented as a pixel value y ij In the reference correction, the variation in pixel values ​​among a plurality of line images LP is corrected. Details of the reference correction will be described below.

[0058] In the reference correction, the pixel values ​​of the pixels in each of the multiple line images LP are corrected using the difference between the average value of the pixel value obtained from the first pixel Lna and the pixel value obtained from the second pixel Lnb and the reference value. The first pixel Lna and the second pixel Lnb represent pixels located at both ends of each of the multiple line images LP. For example, the first line image L1 of the multiple line images LP includes a first pixel L1a and a second pixel L1b located at both ends of the first line image L1. The second line image L2 of the multiple line images LP includes a first pixel L2a and a second pixel L2b located at both ends of the second line image L2.

[0059] The pixel value of the first pixel Lna is a pixel value corresponding to the intensity of light from the first reflector 91 in each of the multiple line images LP. The first pixel Lna is located at one end of each of the multiple line images LP. The pixel value of the second pixel Lnb is a pixel value corresponding to the intensity of light from the second reflector 92 in each of the multiple line images LP. The second pixel Lnb is located at the other end of each of the multiple line images LP. The number of each of the first pixels Lna and second pixels Lnb shown in FIG. 8 may be multiple.

[0060] 8 are pixel values ​​corresponding to the intensity of light from the first reflector 91 in each of the first line image L1 and the second line image L2. The pixel values ​​of the second pixels L1b and L2b are pixel values ​​corresponding to the intensity of light from the second reflector 92 in each of the first line image L1 and the second line image L2.

[0061] In the reference correction, the pixel value y is calculated using the following formula (2): ij is corrected to pixel value z ij is obtained.

number

[0062] Coefficients A, A j is the correction coefficient for the reference correction. Coefficient A j is the average value of the pixel value of the first pixel Lna and the pixel value of the second pixel Lnb in the j-th line image among the multiple line images LP. The coefficient A is a reference value in the reference correction. The coefficient A is the average value of the pixel value of the first pixel Lna and the pixel value of the second pixel Lnb in all of the multiple line images LP.

[0063] According to the substrate inspection module CM, the pixel values ​​of the pixels in each of the line images LP are corrected by the pixel value of the first pixel Lna and the pixel value of the second pixel Lnb. That is, the pixel values ​​of the pixels are corrected based on the intensity of light from the first reflector 91, which has a higher reflectance to light than the surroundings, and the intensity of light from the second reflector 92, which has a higher reflectance to light than the surroundings. Therefore, the variation in pixel values ​​between the line images LP in the image WP of the substrate W, which is caused by the variation when each of the line images LP is captured, is corrected. The variation when capturing may be caused by the variation in the intensity of light from the light irradiation unit 70 and / or the variation in the shutter speed of the imaging unit 8.

[0064] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. In addition, elements in different embodiments can be combined to form other embodiments.

[0065] The first reflecting material and the second reflecting material are not limited to the first reflecting plate 91 and the second reflecting plate 92 shown in Figs. 5 to 7. Each of the first reflecting material and the second reflecting material does not have to have a plate shape. The first reflecting material and the second reflecting material may be a material arranged to cover the inner surface of the housing 5. The reflectance of the material to light is higher than the reflectance of the inner surface of the housing 5 to light. Each of the first reflecting material and the second reflecting material may be a part of a single reflecting material. In this case, the single reflecting material is arranged below the light direction conversion unit, and may include a first part and a second part arranged on both sides of the transport path in a direction intersecting or perpendicular to the transport path.

[0066] The calculation of the first correction is not limited to the calculation of formula (1). The control unit CU does not need to apply the first correction to each of the multiple line images LP. In this case, the pixel value x ijThe second correction is applied to a plurality of line images LP having the above-mentioned. The calculation of the second correction is not limited to the calculation of the formula (2). The coefficient A used in the calculation of the formula (2) may be a predetermined value.

[0067] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims. [Explanation of symbols]

[0068] 1...plasma processing apparatus, 2...control unit, 5...housing, 7...light direction conversion unit, 8...imaging unit, 61...substrate holding unit, 63...driving unit, 70...light irradiation unit, 91...first reflecting plate, 92...second reflecting plate, 91a, 92a...light reflecting surface, CM...substrate inspection module, CU...control unit, LP...multiple line images, Lna...first pixel, Lnb...second pixel, LL1, LL2...load lock module, LP1 to LP4...load ports, P...transport path, PS...substrate processing system, W...substrate, WP...image.

Claims

1. an atmospheric transfer module; a load lock module connected to the atmospheric transfer module; a vacuum transfer module connected to the load lock module; a plasma processing module connected to the vacuum transfer module; A load port connected to the atmospheric transfer module; a substrate inspection module connected to the atmospheric transfer module below the load port; Equipped with The substrate inspection module includes: A housing and A substrate holder disposed within the housing; a drive unit configured to move the substrate holder along a transport path within the housing; A light irradiation unit; an imaging unit including a line sensor; a light direction conversion unit disposed above the transport path and configured to change a direction of received light, the light direction conversion unit being configured to irradiate light emitted from the light irradiation unit onto the substrate held by the substrate holding unit and moved along the transport path, and to guide light reflected by the substrate to the imaging unit; A first reflecting material and a second reflecting material are disposed below the light direction changing unit and are disposed on both sides of the transport path in a direction intersecting or perpendicular to the transport path; a control unit configured to correct an image of the substrate that is composed of a plurality of line images based on an output from the line sensor; Including, a reflectance of each of the first reflecting material and the second reflecting material to light is higher than a reflectance of the housing around the first reflecting material and the second reflecting material to light; the control unit is configured to correct pixel values ​​of the plurality of pixels in each of the plurality of line images by using a difference between a reference value and an average value of a pixel value of a first pixel corresponding to an intensity of light from the first reflecting material and a pixel value of a second pixel corresponding to an intensity of light from the second reflecting material in each of the plurality of line images. Substrate processing system.

2. 2. The substrate processing system of claim 1, wherein a first normal direction of the light reflecting surface of the first reflector and a second normal direction of the light reflecting surface of the second reflector are inclined such that the first normal direction and the second normal direction intersect with each other.

3. A housing and A substrate holder disposed within the housing; a drive unit configured to move the substrate holder along a transport path within the housing; A light irradiation unit; an imaging unit including a line sensor; a light direction conversion unit disposed above the transport path and configured to change a direction of received light, the light direction conversion unit being configured to irradiate light emitted from the light irradiation unit onto the substrate held by the substrate holding unit and moved along the transport path, and to guide light reflected by the substrate to the imaging unit; A first reflecting material and a second reflecting material are disposed below the light direction changing unit and are disposed on both sides of the transport path in a direction intersecting or perpendicular to the transport path; a control unit configured to correct an image of the substrate that is composed of a plurality of line images based on an output from the line sensor; Including, a reflectance of each of the first reflecting material and the second reflecting material to light is higher than a reflectance of the housing around the first reflecting material and the second reflecting material to light; the control unit is configured to correct pixel values ​​of the plurality of pixels in each of the plurality of line images by using a difference between a reference value and an average value of a pixel value of a first pixel corresponding to an intensity of light from the first reflecting material and a pixel value of a second pixel corresponding to an intensity of light from the second reflecting material in each of the plurality of line images. Circuit board inspection equipment.

Images