Substrate processing apparatus

Abstract

To determine a destaticization state of a substrate.SOLUTION: A first pin member is arranged on a mount surface side of a through-hole formed in a stage, and is configured to be movable along the through-hole. A second pin member is arranged on a back surface side of the through-hole, and is configured to be movable along the through-hole. A joint portion is provided in the through-hole, and is configured to join the first pin member and the second pin member and be capable of detecting the pressure with which the second pin member presses the first pin member. A seal member is provided on the back surface side beyond the joint portion of the through-hole, and seals a gap between an inner side surface of the through-hole and the second pin member. A drive unit drives the second pin member along the through-hole to the mount surface side and the back surface side. A control unit is configured to stop application of a voltage from a power supply unit to an electrostatic adsorption unit, and determine a destaticization state of a substrate based on the pressure detected by the joint portion when the drive unit moves the second pin member along the through-hole to the mount surface side.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a substrate processing apparatus. [Background technology]

[0002] Patent Document 1 listed below discloses a "static removal method comprising the steps of: introducing a gas into a processing vessel with a substrate placed on an electrostatic chuck; applying a DC voltage whose absolute value is increased to an attracting electrode of the electrostatic chuck until a discharge caused by the gas is started; applying the DC voltage of an absolute value that reaches a charge neutralization region where the charge amount of the substrate becomes zero or approaches zero after the discharge caused by the gas is started; and detaching the substrate from the electrostatic chuck after applying the absolute value of the DC voltage until the charge neutralization region is reached." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-184551 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique for determining a static electricity removal state of a substrate. [Means for solving the problem]

[0005] A substrate processing apparatus according to an embodiment of the present disclosure includes a chamber, a stage, an electrostatic adsorption unit, a power supply unit, a first pin member, a second pin member, a joint unit, a seal member, a drive unit, and a control unit. The chamber is configured to be capable of decompressing the interior. The stage is disposed within the chamber, and is formed with a mounting surface on which a substrate is placed, and is formed with a through hole penetrating the mounting surface and a back surface of the mounting surface. The electrostatic adsorption unit is provided on the mounting surface portion of the stage, and is configured to be capable of electrostatically adsorbing the substrate when a voltage is applied. The power supply unit is electrically connected to the electrostatic adsorption unit, and is configured to be capable of applying a voltage to the electrostatic adsorption unit. The first pin member is disposed on the mounting surface side of the through hole, and is configured to be movable along the through hole. The second pin member is disposed on the back surface side of the through hole, and is configured to be movable along the through hole. The joint unit is provided in the through hole, joins the first pin member and the second pin member, and is configured to be capable of detecting a pressure with which the second pin member presses the first pin member. The sealing member is provided on the back surface side of the joint portion of the through hole and seals a gap between the inner surface of the through hole and the second pin member. The drive unit drives the second pin member along the through hole to the mounting surface side and the back surface side. The control unit is configured to stop application of voltage from the power supply unit to the electrostatic adsorption unit and determine a static electricity removal state of the substrate based on a pressure detected by the joint portion when the drive unit moves the second pin member along the through hole to the mounting surface side. Effect of the Invention

[0006] According to the present disclosure, the static electricity removal state of the substrate can be determined. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus. [Diagram 2] FIG. 2 is a diagram showing a simplified example of the configuration of the main body part according to the embodiment. [Diagram 3] FIG. 3 is a diagram showing an example of a state in which the substrate according to the embodiment is attracted to the electrostatic chuck. [Figure 4A] FIG. 4A is a diagram showing an example of a change in pressure detected by a bonding portion according to the embodiment. [Figure 4B] FIG. 4B is a diagram showing an example of a change in torque of the motor of the drive unit according to the embodiment. [Diagram 5] FIG. 5 is a flowchart illustrating an example of the ejection process according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of a substrate processing apparatus will be described in detail with reference to the drawings. Note that the substrate processing apparatus disclosed below is not limited to the following embodiment.

[0009] Conventionally, there has been known a substrate processing apparatus in which a substrate such as a semiconductor wafer (hereinafter also referred to as "wafer") is placed on a stage provided inside a chamber, and the inside of the chamber is made into a reduced pressure environment, and substrate processing such as plasma processing is performed on the substrate. An electrostatic check is provided on the stage. In the substrate processing apparatus, the substrate is electrostatically attracted to the substrate by an electrostatic chuck during substrate processing, preventing the substrate from moving. Also, a through hole is formed in the stage, and lifter pins are stored in the stage. In the plasma processing apparatus, the lifter pins are projected from the through hole of the stage, and the substrate is supported by the lifter pins, and the substrate is lifted from the stage to load and unload the substrate. In this manner, in the substrate processing apparatus, the substrate is transported into the chamber, and operations such as lifting, lowering, and placement are generated. In order to handle the substrate smoothly, the adsorption and detachment operations of the substrate are important.

[0010] However, when the electrostatic force is released and the substrate is raised from the electrostatic check, if the substrate is not sufficiently de-ionized, a strong residual adhesive force will be generated, which may cause the substrate to jump up, become misaligned, be damaged by falling, generate particles, etc. To avoid these risks, it is necessary to detect the residual adhesive force of the substrate and achieve an appropriate de-ionization state.

[0011] Therefore, conventionally, the static electricity removal state of the substrate is judged indirectly by using the torque of a drive motor that raises and lowers the lifter pins.

[0012] However, to maintain a reduced pressure environment inside the processing vessel, a sealing member such as an O-ring is provided between the through hole and the lifter pin. The lifter pin slides against the sealing member when it moves up and down. The sliding friction with the sealing member changes over time due to deterioration such as hardening of the sealing member. In addition, the friction of the drive system that moves the lifter pin up and down changes over time due to deterioration such as lack of grease. For this reason, the static electricity removal state of the substrate cannot be determined by the torque of the motor. Therefore, technology that can determine the static electricity removal state of the substrate is desired.

[0013] (Embodiment) (Configuration of the substrate processing apparatus) An example of a substrate processing apparatus according to the present disclosure will be described below. In the embodiment described below, a substrate processing apparatus according to the present disclosure will be described as a plasma processing system in a system configuration.

[0014] An example of the configuration of a plasma processing system will be described below. Fig. 1 is a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus.

[0015] The plasma processing system includes a capacitively coupled plasma processing device 1 and a control unit 2. The capacitively coupled plasma processing device 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing device 1 also includes a substrate support 11 and a gas inlet. In an embodiment, the plasma processing chamber 10 corresponds to the chamber of the present disclosure. The gas inlet is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas inlet includes a shower head 13. The substrate support 11 is disposed in the plasma processing chamber 10. The shower head 13 is disposed above the substrate support 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s and at least one gas exhaust port for exhausting gas from the plasma processing space. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0016] 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. In the embodiment, the main body 111 corresponds to a stage of the present disclosure, and the central region 111a corresponds to a mounting surface of the present disclosure. 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.

[0017] The main body 111 has a plurality of through holes 113, for example, three through holes 113, formed in the central region 111a. Two through holes 113 are shown in Fig. 1. The through holes 113 penetrate from the upper surface to the lower surface of the main body 111. A lifter pin 114 is provided in each through hole 113.

[0018] The lower end of each lifter pin 114 is connected to a drive unit 120. The drive unit 120 is provided with a motor, and drives each lifter pin 114 along the axial direction of the through hole 113 by the driving force of the motor. Each lifter pin 114 is moved in the axial direction of the through hole 113 by the drive unit 120, and its tip can protrude and retract from the central region 111a. When transporting the substrate W, the lifter pins 114 protrude from the main body 111 and lift up the substrate W from the central region 111a.

[0019] 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. In the embodiment, the electrostatic chuck 1111 corresponds to the electrostatic attraction unit of the present disclosure. 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 a radio frequency (RF) power source 31 and / or a direct current (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 a plurality of lower electrodes. Also, the electrostatic electrode 1111b may function as a lower electrode. Thus, the substrate support 11 includes at least one lower electrode.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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 one or more flow modulation devices to modulate or pulse a flow rate of the at least one process gas.

[0024] 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 a plasma generating unit configured to generate a plasma from one or more processing gases in the plasma processing chamber 10. In addition, a bias potential is generated on the substrate W by supplying a bias RF signal to the at least one lower electrode, and ion components in the formed plasma can be attracted to the substrate W.

[0025] 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.

[0026] 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.

[0027] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. In an embodiment, the DC power supply 32 corresponds to the power supply section of the present disclosure. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In an 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 bias DC signal is applied to the at least one lower electrode. In an 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.

[0028] In various embodiments, at least one of 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 thereof pulse waveform. 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.

[0029] 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.

[0030] 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, a communication interface 2a3, and a display unit 2a4. The control unit 2 is realized by, for example, 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 thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0031] (Configuration of main body 111) Fig. 2 is a simplified diagram showing an example of the configuration of the main body 111 according to the embodiment. Fig. 2 shows a configuration for raising and lowering the lifter pins 114.

[0032] The main body 111 of the substrate support 11 has a central region 111a formed in the center of its upper surface for supporting the substrate W, and an annular region 111b formed around the central region 111a of the upper surface for supporting the ring assembly 112. The main body 111 has a through hole 113 formed in the central region 111a, which penetrates through the central region 111a and a back surface 111c opposite the central region 111a. Two through holes 113a, 113b are shown in FIG. 2.

[0033] The main body 111 has a base 1110 and an electrostatic chuck 1111. The base 1110 and the electrostatic chuck 1111 are stacked.

[0034] The central portion of the upper surface of the electrostatic chuck 1111 is a central region 111a, and the peripheral portion of the upper surface of the electrostatic chuck 1111 surrounding the central region 111a is an annular region 111b. The electrostatic chuck 1111 has an electrostatic electrode 1111b disposed within the ceramic member 1111a. The electrostatic electrode 1111b is electrically connected to a DC power supply 32. When a direct current voltage is applied from the DC power supply 32, the electrostatic chuck 1111 electrostatically attracts the substrate W placed on the central region 111a.

[0035] A lifter pin 114 is provided in each through hole 113 of the main body 111. Any one of the lifter pins 114 is configured by joining a first pin member 115a and a second pin member 115b by a joining portion 115c. In this embodiment, the lifter pin 114a provided in the through hole 113a is divided into a first pin member 115a and a second pin member 115b.

[0036] The lifter pins 114 other than the lifter pin 114a are each formed in a rod shape with a predetermined radius. The first pin member 115a and the second pin member 115b are each formed in a rod shape with a predetermined radius. The first pin member 115a and the second pin member 115b are joined by a joint 115c. For example, the joint 115c has connection parts 115d at both ends that can connect the first pin member 115a and the second pin member 115b. A screw thread is formed at the lower end of the first pin member 115a and the upper end of the second pin member 115b. A screw groove is formed at the joint 115c of the joint 115c. The lower end of the first pin member 115a and the upper end of the second pin member 115b are inserted into the connection parts 115d at both ends of the joint 115c and the screws are fastened, so that the first pin member 115a and the second pin member 115b are joined via the joint 115c.

[0037] Each lifter pin 114 including the lifter pin 114a is moved up and down along the axial direction of the through hole 113 by a drive unit 120 to raise and lower the substrate W.

[0038] Each through hole 113 is formed with a diameter slightly larger than the diameter of the lifter pin 114. Each through hole 113 has a gap between the lifter pin 114 sealed by a seal member 116 such as an O-ring. Here, in the lifter pin 114a, the joint portion 115c is formed thicker than the first pin member 115a and the second pin member 115b. Therefore, the through hole 113a in which the lifter pin 114a is stored is formed with a diameter slightly larger than the diameter of the joint portion 115c in the movement range in which the joint portion 115c moves when the substrate W is raised and lowered. For example, the length of the first pin member 115a and the second pin member 115b of the lifter pin 114a is adjusted so that the movement range of the joint portion 115c when the substrate W is raised and lowered is near the center of the base 1110. The through hole 113a is formed so that the diameter is slightly larger than the diameter of the joint portion 115c from the joint surface of the base 1110 with the electrostatic chuck 1111 to the vicinity of the center. The through hole 113a is formed so that the diameters near both ends on the central region 111a side and the back surface 111c side are slightly larger than the diameters of the first pin member 115a and the second pin member 115b. The through hole 113a is sealed by a seal member 116 on the back surface 111c side of the joint portion 115c. For example, the seal member 116 is provided in the through hole 113a near the lower end where the diameter corresponds to the second pin member 115b.

[0039] The joint 115c is configured to be capable of detecting the pressure with which the second pin member 115b presses the first pin member 115a. For example, the joint 115c has a built-in sensor capable of detecting pressure, such as a piezoelectric element or a strain gauge, and is capable of detecting pressure in a direction along the through hole 113. The second pin member 115b is provided with a wiring 115e connected to the sensor, and the sensor can detect pressure via the wiring 115e. Data on the pressure detected by the sensor is transmitted to the control unit 2.

[0040] Next, the operation of the plasma processing apparatus 1 will be described. First, the operation of the plasma processing apparatus 1 when the substrate W is carried into the plasma processing apparatus 1 will be described. When the substrate W is carried into the plasma processing apparatus 1, an unillustrated loading / unloading port provided in the plasma processing chamber 10 is opened. The substrate W is carried into the plasma processing chamber 10 from the loading / unloading port by a transport mechanism such as a transport arm. The control unit 2 controls the drive unit 120 to raise the lifter pins 114 from the main body unit 111. When the lifter pins 114 are raised, the substrate W is supported by the lifter pins 114. As a result, the substrate W is transferred from the drive unit 120 to the lifter pins 114. After receiving the substrate W, the transport mechanism exits from the plasma processing chamber 10. After the transport mechanism exits, the control unit 2 controls the drive unit 120 to lower the lifter pins 114 to accommodate the lifter pins 114 in the main body unit 111, and the substrate W is placed in the central region 111a.

[0041] Next, the operation of the plasma processing apparatus 1 when the substrate W is subjected to substrate processing will be described. The operation when the substrate W is subjected to plasma etching as the substrate processing will be described below. The control unit 2 controls the DC power supply 32 to apply a DC voltage from the DC power supply 32 to the electrostatic electrode 1111b of the electrostatic chuck 1111, and electrostatically attracts the substrate W placed on the central region 111a. The control unit 2 controls the exhaust system 40 to exhaust the inside of the plasma processing chamber 10 to a predetermined vacuum level. The control unit 2 controls the gas supply unit 20 to introduce a processing gas for etching from the gas supply unit 20 into the plasma processing space 10s. The control unit 2 controls the power supply 30 to supply power from the power supply 30 in accordance with the introduction of the processing gas, thereby generating plasma in the plasma processing chamber 10, and etching the substrate W.

[0042] Next, the operation of the plasma processing apparatus 1 when the substrate W after the substrate processing is unloaded from the plasma processing apparatus 1 will be described. The substrate W after the substrate processing may have residual electric charge and may be adsorbed to the electrostatic chuck 1111. Therefore, when the substrate W is unloaded from the plasma processing apparatus 1, the plasma processing apparatus 1 performs a charge removal process to remove the residual electric charge from the substrate W. For example, the control unit 2 controls the DC power supply 32 to stop the application of a DC voltage from the DC power supply 32 to the electrostatic electrode 1111b of the electrostatic chuck 1111, thereby releasing the electrostatic force. The control unit 2 controls the gas supply unit 20 to introduce an inert gas such as argon gas from the gas supply unit 20 into the plasma processing space 10s. The control unit 2 controls the power supply 30 to supply electric power from the power supply 30 in accordance with the introduction of the inert gas, thereby generating plasma in the plasma processing chamber 10. Note that, during charge removal, a DC voltage of a polarity opposite to that during the substrate processing may be applied from the DC power supply 32 to the electrostatic electrode 1111b of the electrostatic chuck 1111. Alternatively, positive and negative DC voltages may be applied alternately from the DC power supply 32 to the electrostatic electrode 1111 b of the electrostatic chuck 1111 .

[0043] After the charge removal process, the substrate W is unloaded from the plasma processing apparatus 1. When unloading the substrate W from the plasma processing apparatus 1, the control unit 2 controls the drive unit 120 to raise the lifter pins 114 from the main body unit 111, and the substrate W is supported and lifted by the lifter pins 114. An unillustrated loading / unloading port provided in the plasma processing chamber 10 is opened. The transport mechanism enters the lower part of the substrate W that has been lifted from the loading / unloading port. When the transport mechanism enters the lower part of the substrate W, the control unit 2 controls the drive unit 120 to lower the lifter pins 114 to accommodate the lifter pins 114 in the main body unit 111. When the lifter pins 114 are lowered, the substrate W is supported by the transport mechanism. Thus, the substrate W is transferred from the lifter pins 114 to the transport mechanism. After receiving the substrate W, the transport mechanism exits the plasma processing chamber 10.

[0044] However, if the static electricity on the substrate W is not sufficiently removed when the substrate W is unloaded, a strong residual attraction force is generated, which may result in the substrate W bouncing up, being displaced, being damaged by falling, and generating particles.

[0045] Fig. 3 is a diagram showing an example of a state in which the substrate W according to the embodiment is attracted to the electrostatic chuck 1111. Fig. 3 shows a state in which a charge remains on the substrate W, generating a residual attracting force, and the substrate W is attracted to the electrostatic chuck 1111. If the lifter pins 114 are raised in this state in which the substrate W is attracted to the electrostatic chuck 1111, there is a risk that the substrate W will jump up, become displaced, fall, be damaged, generate particles, and so on.

[0046] Therefore, the control unit 2 determines the neutralization state of the substrate W based on the pressure detected by the bonding unit 115c. For example, the control unit 2 stops the application of voltage from the DC power supply 32 to the electrostatic chuck 1111, and causes the driving unit 120 to move each lifter pin 114 along the through hole 113 toward the central region 111a. The control unit 2 determines the neutralization state of the substrate W based on the pressure detected by the bonding unit 115c in this state. For example, the control unit 2 determines whether the pressure detected by the bonding unit 115c is equal to or greater than a predetermined first threshold. The first threshold is set to a value that is greater than the pressure when the substrate W that is not electrostatically attracted is raised from the central region 111a and smaller than the pressure when the substrate W that is electrostatically attracted is raised from the central region 111a. When the pressure detected by the bonding unit 115c is equal to or greater than the first threshold, the control unit 2 determines that a neutralization failure of the substrate has occurred. When the control unit 2 determines that a neutralization failure of the substrate W has occurred, it controls the substrate W to be neutralized. For example, when the control unit 2 determines that a charge removal failure has occurred in the substrate W, the control unit 2 performs the charge removal process again. For example, the control unit 2 controls the gas supply unit 20 to introduce an inert gas such as argon gas from the gas supply unit 20 into the plasma processing space 10s. The control unit 2 controls the power supply 30 to supply power from the power supply 30 in accordance with the introduction of the inert gas to generate plasma in the plasma processing chamber 10. Note that, during charge removal, a DC voltage of the opposite polarity to that during substrate processing may be applied from the DC power supply 32 to the electrostatic electrode 1111b of the electrostatic chuck 1111. Also, positive and negative DC voltages may be applied alternately from the DC power supply 32 to the electrostatic electrode 1111b of the electrostatic chuck 1111.

[0047] Incidentally, friction occurring when lifter pins 114 are lifted increases due to deterioration, such as grease exhaustion, in drive unit 120 and deterioration of seal member 116. When deterioration occurs in the drive mechanism for driving lifter pins 114, such as drive unit 120 and seal member 116, plasma processing apparatus 1 requires maintenance.

[0048] Therefore, the control unit 2 indirectly uses the torque, speed, etc. generated in the motor of the drive unit 120 to control output of a warning. For example, the motor of the drive unit 120 transmits torque data to the control unit 2. The control unit 2 uses the torque generated in the motor of the drive unit 120 to determine the deterioration state of the drive mechanism that drives the lifter pins 114. The control unit 2 determines whether the pressure detected by the joint 115c is smaller than a first threshold value and the torque of the motor of the drive unit 120 is equal to or greater than a predetermined second threshold value. The second threshold value is set to a value at which the drive mechanism that drives the lifter pins 114 is considered to be deteriorated. For example, the second threshold value is set to the smaller value of the torque value of the motor when the drive unit 120 runs out of grease and the torque value of the motor when the seal member 116 is deteriorated. The control unit 2 controls output of a warning when the pressure detected by the joint 115c is smaller than the first threshold value and the torque of the motor of the drive unit 120 is equal to or greater than the second threshold value. For example, the control unit 2 performs control to output to the display unit 2a4 a message indicating that the drive mechanism for driving the lifter pins 114 is deteriorating. For example, the control unit 2 performs control to output to the display unit 2a4 a message indicating that the drive unit 120 is out of grease or the seal member 116 is deteriorating.

[0049] FIG. 4A is a diagram showing an example of a change in pressure detected by the joint 115c according to the embodiment. FIG. 4B is a diagram showing an example of a change in torque of the motor of the drive unit 120 according to the embodiment. FIG. 4A shows a change in pressure detected by the joint 115c when the lifter pins 114 are raised from the main body 111 and the substrate W is supported and raised from the main body 111. FIG. 4B shows a change in torque of the motor of the drive unit 120 when the lifter pins 114 are raised from the main body 111 and the substrate W is supported and raised from the main body 111. Case 1 shows a case where charges remain on the substrate W and the substrate W is adsorbed to the electrostatic chuck 1111 (residual adsorption), the drive mechanism for driving the lifter pins 114 is not deteriorated, and the friction for lifting the lifter pins 114 is small (small friction). Case 2 shows a case where no charge remains on the substrate W, the substrate W is not adsorbed to the electrostatic chuck 1111 (no residual adsorption), the driving mechanism that drives the lifter pins 114 is deteriorated, and the friction that lifts the lifter pins 114 is large (large friction).

[0050] 4B, the torque of the motor of the drive unit 120 is equal to or greater than the second threshold value in both cases 1 and 2. Therefore, the static electricity removal state of the substrate W cannot be determined by the torque of the motor of the drive system that raises and lowers the lifter pins as in the conventional method.

[0051] In contrast, as shown in Case 1 of FIG. 4A, when there is residual adhesion, the pressure detected by the bonding portion 115c is equal to or greater than the first threshold. On the other hand, as shown in Case 2 of FIG. 4A, when there is no residual adhesion, the pressure detected by the bonding portion 115c is less than the first threshold. Therefore, by determining whether the pressure detected by the bonding portion 115c is equal to or greater than the first threshold, the charge removal state of the substrate W can be determined. In this embodiment, it can be determined whether charge remains on the substrate W and the substrate W is attracted to the electrostatic chuck 1111.

[0052] 4A and 4B, when there is residual adhesion and low friction, the pressure detected by the joint 115c is equal to or greater than the first threshold, and the torque of the motor of the drive unit 120 is equal to or greater than the second threshold. On the other hand, when there is no residual adhesion and high friction, as shown in Case 2 of FIG. 4A and 4B, the pressure detected by the joint 115c is less than the first threshold, and the torque of the motor of the drive unit 120 is equal to or greater than the second threshold. Therefore, by determining whether the pressure detected by the joint 115c is less than the first threshold and the torque of the motor of the drive unit 120 is equal to or greater than the second threshold, it is possible to determine whether the drive mechanism that drives the lifter pins 114 has deteriorated.

[0053] Next, a description will be given of the flow of an unloading process for unloading the substrate W from the plasma processing chamber 10, including a determination process for determining the static electricity removal state of the substrate W. Fig. 5 is a flow chart showing an example of the unloading process according to the embodiment.

[0054] The control unit 2 controls the DC power supply 32 to stop the application of a DC voltage from the DC power supply 32 to the electrostatic electrode 1111b of the electrostatic chuck 1111, thereby releasing the electrostatic attraction (step S10).

[0055] Next, the control unit 2 performs a charge removal process to remove charge from the substrate W (step S11). For example, the control unit 2 controls the gas supply unit 20 to introduce an inert gas such as argon gas from the gas supply unit 20 into the plasma processing space 10s. The control unit 2 controls the power supply 30 to supply power from the power supply 30 in accordance with the introduction of the inert gas, thereby generating plasma in the plasma processing chamber 10.

[0056] Next, the control unit 2 controls the drive unit 120 to start raising the lifter pins 114 (step S12). The control unit 2 determines whether the pressure detected by the joint 115c is equal to or greater than the first threshold (step S13). If the pressure detected by the joint 115c is equal to or greater than the first threshold (step S13: Yes), the control unit 2 controls the drive unit 120 to lower the lifter pins 114 and accommodate the lifter pins 114 in the main body 111 (step S14). Thereafter, the process proceeds to the above-mentioned step S11 to perform static elimination again.

[0057] On the other hand, if the pressure detected by the joint 115c is smaller than the first threshold (step S13: No), the control unit 2 determines whether the torque of the motor of the drive unit 120 is equal to or greater than the second threshold (step S15). If the torque of the motor of the drive unit 120 is equal to or greater than the second threshold (step S15: Yes), the control unit 2 performs control to output a warning regarding the drive mechanism that drives the lifter pins 114 (step S16), and proceeds to step S17, which will be described later.

[0058] On the other hand, if the torque of the motor of the drive unit 120 is smaller than the second threshold value (step S15: No), the controller 2 controls the drive unit 120 to raise the lifter pins 114 to a height for loading and unloading the substrate W (step S17).

[0059] When the transport mechanism enters below the substrate W, the control unit 2 controls the drive unit 120 to lower the lifter pins 114 and house the lifter pins 114 in the main body unit 111 (step S18), thereby completing the process.

[0060] The embodiment has been described above. As described above, the plasma processing system according to the embodiment includes the plasma processing chamber 10, the main body 111, the electrostatic chuck 1111, the DC power supply 32, the first pin member 115a, the second pin member 115b, the joint 115c, the seal member 116, the drive unit 120, and the control unit 2. The plasma processing chamber 10 is configured so that the inside can be depressurized. The main body 111 is disposed in the plasma processing chamber 10, and a central region 111a on which the substrate W is placed is formed, and a through hole 113 is formed through the central region 111a and the back surface 111c relative to the central region 111a. The electrostatic chuck 1111 is provided in the central region 111a of the main body 111, and is configured so that the substrate W can be electrostatically attracted when a voltage is applied. The DC power supply 32 is electrically connected to the electrostatic chuck 1111, and is configured so that a voltage can be applied to the electrostatic chuck 1111. The first pin member 115a is disposed on the central region 111a side of the through hole 113 and is configured to be movable along the through hole 113. The second pin member 115b is disposed on the back surface 111c side of the through hole 113 and is configured to be movable along the through hole 113. The joint portion 115c is provided in the through hole 113, joins the first pin member 115a and the second pin member 115b, and is configured to be able to detect the pressure with which the second pin member 115b presses the first pin member 115a. The seal member 116 is provided on the back surface 111c side of the joint portion 115c of the through hole 113 and seals the gap between the inner surface of the through hole 113 and the second pin member 115b. The drive unit 120 drives the second pin member 115b along the through hole 113 toward the central region 111a side and the back surface 111c side. The control unit 2 is configured to stop application of a voltage from the DC power supply 32 to the electrostatic chuck 1111, and determine the neutralization state of the substrate W based on the pressure detected by the bonding portion 115c when the driving unit 120 moves the second pin member 115b toward the central region 111a along the through hole 113. In this way, the plasma processing system according to the embodiment can determine the neutralization state of the substrate W.

[0061] The control unit 2 is configured to determine whether the pressure detected by the bonding unit 115c is equal to or greater than a predetermined first threshold value that is greater than the pressure when a non-electrostatically attracted substrate W is raised from the central region 111a and less than the pressure when an electrostatically attracted substrate W is raised from the central region 111a, and to determine that a charge removal failure of the substrate W has occurred when the pressure detected by the bonding unit 115c is equal to or greater than the first threshold value. In this way, the plasma processing system according to the embodiment can determine whether a charge removal failure of the substrate W has occurred.

[0062] Furthermore, when it is determined that a charge removal failure has occurred in the substrate W, the control unit 2 is configured to perform control so as to remove charge from the substrate W. In this way, the plasma processing system according to the embodiment can eliminate the charge removal failure in the substrate W.

[0063] Further, the driving unit 120 moves the second pin member 115b along the through hole 113 by the driving force of the motor. The control unit 2 is configured to determine whether the pressure detected by the joint 115c is smaller than the first threshold value and the torque of the motor is equal to or greater than a predetermined second threshold value at which the driving mechanism for driving the second pin member 115b is deemed to be deteriorated, and to perform control to output a warning when the pressure detected by the joint 115c is smaller than the first threshold value and the torque of the motor is equal to or greater than the second threshold value. In this way, the plasma processing system according to the embodiment can notify the occurrence of a friction failure in the driving mechanism for driving the lifter pins 114, and can prompt the maintenance of the plasma processing system.

[0064] In the above embodiment, one lifter pin 114a is configured by joining first pin member 115a and second pin member 115b with joint portion 115c. However, this is not limited to the above. A plurality of or all of the lifter pins 114 may be configured by joining first pin member 115a and second pin member 115b with joint portion 115c.

[0065] In the above embodiment, the substrate processing apparatus is described as a plasma processing apparatus 1 that processes a substrate W using plasma. However, the present invention is not limited to this. The disclosed technology can be applied to other substrate processing apparatuses that do not use plasma, so long as the substrate processing apparatus processes a substrate W.

[0066] In the above embodiment, the plasma processing apparatus 1 is described as performing processing using a capacitively coupled plasma (CCP) as an example of a plasma source, but the plasma source is not limited to this. Examples of plasma sources other than the capacitively coupled plasma include inductively coupled plasma (ICP), microwave excited surface wave plasma (SWP), electron cyclotron resonance plasma (ECP), and helicon wave excited plasma (HWP).

[0067] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be construed as limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0068] 1. Plasma processing equipment 2. Control section 2a Computer 2a1 Processing section 2a2 Storage section 2a3 Communication Interface 2a4 display section 10 Plasma Processing Chamber 11 Substrate support 30 power supply 31 RF power supply 31a First RF generation unit 31b Second RF generation unit 32 DC power supply 32a First DC generation unit 32b Second DC generation section 40 Exhaust system 111 Main body 111a Central area 111b Annular region 111c back side 112 Ring Assembly 113, 113a, 113b through hole 114, 114a Lifter pin 115a first pin member 115b second pin member 115c joint 115d Connection 115e Wiring 116 Sealing material 120 Drive unit 1110 Foundation 1110a Flow path 1111 Electrostatic Chuck 1111a Ceramic components 1111b Electrostatic electrode W substrate

Claims

1. A chamber configured so that the inside can be decompressed; a stage disposed within the chamber, the stage having a mounting surface on which a substrate is placed and a through hole formed therein, the through hole penetrating the mounting surface and a rear surface opposite to the mounting surface; an electrostatic attraction unit provided on the mounting surface of the stage and configured to electrostatically attract the substrate when a voltage is applied thereto; a power supply unit electrically connected to the electrostatic attraction unit and configured to be able to apply a voltage to the electrostatic attraction unit; a first pin member disposed on the mounting surface side of the through hole and configured to be movable along the through hole; A second pin member is disposed on the back surface side of the through hole and configured to be movable along the through hole; a joint portion provided in the through hole, joining the first pin member and the second pin member, and configured to be capable of detecting a pressure by which the second pin member presses the first pin member; a seal member provided on the rear surface side of the through hole relative to the joint portion and configured to seal a gap between an inner surface of the through hole and the second pin member; a drive unit configured to drive the second pin member along the through hole toward the placement surface side and the back surface side; a control unit configured to stop application of a voltage from the power supply unit to the electrostatic attraction unit and determine a static electricity removal state of the substrate based on a pressure detected by the bonding unit when the second pin member is moved toward the placement surface along the through hole by the drive unit; and A substrate processing apparatus comprising:

2. The control unit is configured to determine whether the pressure detected by the bonding unit is equal to or greater than a predetermined first threshold value that is greater than a pressure when the non-electrostatically attracted substrate is raised from the placement surface and less than a pressure when the electrostatically attracted substrate is raised from the placement surface, and to determine that a static electricity removal failure of the substrate has occurred when the pressure detected by the bonding unit is equal to or greater than the first threshold value. The substrate processing apparatus according to claim 1 .

3. The control unit is configured to perform control so as to eliminate electricity from the substrate when it is determined that a static elimination failure has occurred in the substrate. The substrate processing apparatus according to claim 2 .

4. the drive unit moves the second pin member along the through hole by a driving force of a motor, The control unit is configured to determine whether the pressure detected by the joint unit is smaller than the first threshold value and the torque of the motor is equal to or greater than a predetermined second threshold value at which a drive mechanism that drives the second pin member is deemed to have deteriorated, and to perform control to output a warning regarding the drive unit when the pressure detected by the joint unit is smaller than the first threshold value and the torque of the motor is equal to or greater than the second threshold value. The substrate processing apparatus according to claim 2 or 3.

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