SUBSTRATE PROCESSING SYSTEM

A substrate processing system including a plasma processing apparatus including a processing container, a decompressed transferrer connected to the plasma processing apparatus, and a controller, a substrate support, a ring placing surface for receiving an edge ring, and an electrostatic chuck for electrostatically attracting the edge ring to the ring placing surface, a supply path for supplying a gas between a rear surface of the edge ring and the ring placing surface, and a pressure sensor connected to the supply path, the edge ring is placed on the ring placing surface, gas is supplied to the supply path to maintain a pressure in the supply path to be higher than a pressure in the processing container, the pressure in the supply path is measured by the pressure sensor to determine a placing state of the edge ring on the ring placing surface.

TECHNICAL FIELD

The present disclosure relates to a substrate processing system.

BACKGROUND

Patent Document 1 discloses a focus ring replacing method for replacing a focus ring that is used in a plasma processing apparatus capable of performing plasma processing on a substrate placed on a stage provided in a processing space, and that is placed on the stage to surround a periphery of the substrate. The replacing method includes an unloading step of unloading the focus ring from the processing space via a transfer device that transfers the focus ring, without exposing the processing space to the atmosphere, and a cleaning step of cleaning a surface of the stage on which the focus ring is placed after the unloading step. The replacing method further includes a loading step of, after the cleaning step, loading the focus ring into the processing space via the transfer device without exposing the processing space to the atmosphere and placing the focus ring on the stage. Patent Document 1 also discloses performing charge neutralization before the unloading step when the focus ring is attracted to the stage by an electrostatic chuck.

CITATION LIST

Patent Documents

SUMMARY

In the technique according to the present disclosure, an edge ring is accurately placed on a substrate support.

According to an aspect of the present disclosure, there is provided a substrate processing system having a plasma processing apparatus, a pressure-reduced transfer device connected to the plasma processing apparatus, and a controller, in which the plasma processing apparatus has a processing container configured to be pressure-reduced, a substrate support that is provided in the processing container and that includes a substrate placing surface, a ring placing surface on which an edge ring is placed to surround the substrate placing surface, and an electrostatic chuck that electrostatically attracts the edge ring to the ring placing surface, an elevation mechanism that elevates the edge ring with respect to the ring placing surface, a supply path for supplying a gas to a space between a rear surface of the edge ring and the ring placing surface, and a pressure sensor connected to the supply path, the pressure-reduced transfer device has a transfer robot that transfers the edge ring, and the controller controls lowering the edge ring that is transferred into the processing container by the transfer robot and that is transferred to the elevation mechanism, via the elevation mechanism and placing the edge ring on the ring placing surface, electrostatically attracting the placed edge ring to the ring placing surface, supplying the gas to the supply path to maintain a pressure in the supply path to be higher than a pressure in the processing container after the electrostatic attracting, measuring the pressure in the supply path, and determining a placing state of the edge ring on the ring placing surface based on the measured pressure.

According to the present disclosure, an edge ring can be accurately placed on a substrate support.

DETAILED DESCRIPTION

In a manufacturing process of a semiconductor device or the like, a substrate such as a semiconductor wafer (hereinafter referred to as “wafer”) is subjected to substrate processing such as etching processing using a plasma, that is, plasma processing. The plasma processing is performed in a state where the substrate is placed on a substrate support in a pressure-reduced processing container.

In order to obtain an accurate and uniform plasma processing result at a central portion and a peripheral portion of the substrate, a structure (also referred to as a member) having an annular shape in plan view, which is so-called a focus ring, an edge ring, or the like (hereinafter referred to as “edge ring”), may be placed on the substrate support to surround a periphery of the substrate on the substrate support.

Since the result of the plasma processing depends on a temperature of the substrate, a temperature of the substrate support is adjusted during the plasma processing, and the temperature of the substrate is adjusted through the substrate support.

When the edge ring is used, temperature adjustment of the edge ring is also important because a temperature of the edge ring affects the plasma processing result of the peripheral portion of the substrate. Thus, the temperature of the edge ring is also adjusted through the substrate support.

However, when the substrate and the edge ring are simply placed on the substrate support, a vacuum heat insulating layer is formed between the substrate support and the substrate and the edge ring, and temperature adjustment through the substrate support cannot be appropriately performed. In order to improve this point, an electrostatic chuck is provided on the substrate support, and the substrate and the edge ring are electrostatically attracted to the electrostatic chuck.

Further, since the edge ring is etched and consumed by being exposed to the plasma, it is necessary to replace the edge ring. Generally, replacement when the edge ring is consumed is performed by a worker by exposing the processing container to the atmosphere. However, it is also considered to perform replacement without exposing the processing container to the atmosphere using a transfer device that transfers the edge ring (see Patent Document 1).

In the case of using the edge ring, it is necessary to set an appropriate position of the edge ring with respect to the substrate support to obtain a uniform processing result in a circumferential direction at the peripheral portion of the substrate. Specifically, for example, positions of a center of the electrostatic chuck and a center of the edge ring need to be substantially the same.

However, when the edge ring is placed on the electrostatic chuck of the substrate support using the transfer device that transfers the edge ring, the position of the edge ring with respect to the substrate support may be inappropriate (e.g., misaligned, including misaligned greater than a threshold amount). Even when the position is appropriate at a time of placing, the edge ring may be misaligned with respect to the substrate support when the edge ring is electrostatically attracted, and the position may be inappropriate.

Therefore, in the technique according to the present disclosure, the edge ring is accurately placed on the substrate support.

Hereinafter, a substrate processing system according to one or more embodiments of the present application will be described with reference to the drawings. Like reference numerals will be given to like parts having substantially the same functions throughout the specification and the drawings, and redundant description thereof will be omitted.

Plasma Processing System

FIG.1is a plan view showing a schematic configuration of a plasma processing system as the substrate processing system according to one or more embodiments of the present application.FIG.2is a diagram showing a schematic configuration of a transfer robot provided in a transfer module (described later).

In a plasma processing system1inFIG.1, a wafer W that is the substrate is processed. Specifically, the wafer W is subjected to the substrate processing such as the etching processing using the plasma, that is, the plasma processing.

The plasma processing system1includes an atmospheric section10and a decompression section11, and the atmospheric section10and the decompression section11are integrally connected to each other through load-lock modules20and21. The atmospheric section10includes an atmospheric module for performing desired processing on the wafer W under an atmospheric pressure atmosphere. The decompression section11includes a decompression module for performing desired processing on the wafer W under a pressure-reduced atmosphere (vacuum atmosphere).

The load-lock modules20and21are connected to a loader module30of the atmospheric section10and a transfer module50of the decompression section11through gate valves (not shown). The load lock modules20and21are configured to temporarily hold the wafer W. Further, each of the load-lock modules20and21is configured such that an inner space thereof can be switched between an atmospheric pressure atmosphere and a pressure-reduced atmosphere.

The atmospheric section10includes the loader module30including a transfer device40(described later), and load ports32for placing hoops31. The hoops31can store a plurality of wafers W. An orienter module (not shown) that adjusts an orientation of the wafer W in a horizontal direction, a buffer module (not shown) that temporarily stores the plurality of wafers W, and the like may be connected to the loader module30.

The loader module30has a rectangular housing, and an inner space of the housing is maintained in an atmospheric pressure atmosphere. A plurality of load ports32, for example, five load ports32, are disposed side by side on one side surface forming a long side of the housing of the loader module30. The load-lock modules20and21are disposed side by side on the other longitudinal side the housing of the loader module30.

The transfer device40configured to hold and transfer the wafer W is provided in the housing of the loader module30. The transfer device40includes a transfer arm41that supports the wafer W during transfer, a rotor42that rotatably supports the transfer arm41, and a base43on which the rotor42is placed. Further, a guide rail44extending in a longitudinal direction of the loader module30is disposed in the loader module30. The base43is disposed on the guide rail44, and the transfer device40is configured to be movable along the guide rail44.

The decompression section11includes the transfer module50serving as a pressure-reduced transfer device, a processing module60serving as a plasma processing apparatus, and an accommodation module61serving as an accommodation. An inner space of each of the transfer module50and the processing module60(specifically, an inner space of each of a pressure-reduced transfer space51and a chamber100(described later)) is maintained in a pressure-reduced atmosphere, and an inner space of the accommodation module61is also maintained in a pressure-reduced atmosphere. A plurality of processing modules60, for example, six processing modules60, and a plurality of accommodation modules61, for example, two accommodation modules61, are provided for one transfer module50. The number and disposition of the processing modules60are not limited to those in one or more embodiments of the present application and may be freely set as long as at least one processing module including a wafer support (described later) is provided. The number and disposition of the accommodation modules61are also not limited to those in one or more embodiments of the present application and can be freely set. For example, at least one accommodation module61is provided.

The transfer module50is configured to transfer the wafer W in the inner space thereof. The transfer module50is also configured to transfer an edge ring E (described later) in the inner space thereof.

The transfer module50includes the pressure-reduced transfer space51having a housing of a polygonal shape in plan view (in the shown example, a quadrangular shape in plan view). The pressure-reduced transfer space51is connected to the load-lock modules20and21.

The transfer module50is configured to transfer the wafer W loaded in the load-lock module20to one processing module60and unload the wafer W subjected to desired plasma processing in the processing module60into the load-lock module21.

Further, the transfer module50may transfer the edge ring E in the accommodation module61to one processing module60and unload the edge ring E in the processing module60into the accommodation module61.

The processing module60performs the desired plasma processing, for example, the etching processing, on the wafer W transferred from the transfer module50. Further, the processing modules60are connected to the transfer module50through gate valves62. A specific configuration of the processing module60will be described later.

The accommodation module61accommodates the edge ring E. Further, the accommodation module61is connected to the transfer module50through a gate valve63.

A transfer robot70is provided in the pressure-reduced transfer space51of the transfer module50. The transfer robot70is configured to hold and transfer the wafer W. The transfer robot70is also configured to hold and transfer the edge ring E.

The transfer robot70includes a transfer arm71that is configured to be swivelled, retracted, and elevated in a state of holding the wafer W. A tip of the transfer arm71branches into forks72and72serving as two holders. The forks72and72are configured to hold the wafer W and the edge ring E to be transferred, respectively. Further, as shown inFIG.2, at least any one of the forks72and72may be provided with a measurement unit73. The measurement unit73measures information related to a misalignment amount of the edge ring E with respect to an electrostatic chuck (described later) provided in the processing module60. The measurement unit73includes, for example, a distance sensor (not shown).

In the transfer module50, the wafer W held in the load-lock module20is received by the transfer arm71and is loaded into the processing module60. Further, the wafer W subjected to desired processing in the processing module60is received by the transfer arm71and is unloaded into the load-lock module21.

Further, in the transfer module50, the transfer arm71may receive the edge ring E in the accommodation module61and load the edge ring E into the processing module60. Further, in the transfer module50, the transfer arm71may receive the edge ring E in the processing module60and unload the edge ring E into the accommodation module61.

The plasma processing system1further includes a controller80. In one or more embodiments of the present application, the controller80processes computer-executable instructions for causing the plasma processing system1to perform various steps described in the present disclosure. The controller80may be configured to control each of other components of the plasma processing system1such that the plasma processing system1performs the various steps to be described here. In one or more embodiments of the present application, the controller80may be partially or entirely included in the components of the plasma processing system1. For example, the controller80may include a computer90. For example, the computer90may include a processor (CPU: central processing unit)91, a storage unit92, and a communication interface93. The functionality of the elements disclosed herein may be implemented using circuitry or processing circuitry which includes general purpose processors, special purpose processors, integrated circuits, ASICs (“Application Specific Integrated Circuits”), FPGAs (“Field-Programmable Gate Arrays”), conventional circuitry and/or combinations thereof which are programmed, using one or more programs stored in one or more memories, or otherwise configured to perform the disclosed functionality. Processors and controllers are considered processing circuitry or circuitry as they include transistors and other circuitry therein. In the disclosure, the circuitry, units, or means are hardware that carry out or are programmed to perform the recited functionality. The hardware may be any hardware disclosed herein which is programmed or configured to carry out the recited functionality. The processor91may be configured to perform various control operations and calculations based on a program stored in the storage unit92. The storage unit92may 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 interface93may communicate with the components of the plasma processing system1through a communication line such as a local area network (LAN).

Wafer Processing in Plasma Processing System1

Next, an example of wafer processing using the plasma processing system1configured as described above will be described.

First, the wafer W is acquired from a desired hoop31by the transfer device40and loaded into the load-lock module20by the transfer device40. Next, the load-lock module20is sealed and decompressed. Thereafter, the inner space of the load-lock module20communicates with the inner space of the transfer module50.

Next, the wafer W is held by the transfer robot70and is transferred from the load-lock module20to the transfer module50.

Next, the gate valve62corresponding to the desired processing module60is open, and the wafer W is loaded into the desired processing module60by the transfer robot70. Then, the gate valve62is closed, and the wafer W is subjected to desired processing in the processing module60. The processing performed on the wafer W in the processing module60will be described later.

Next, the gate valve62is open, and the wafer W is unloaded from the processing module60by the transfer robot70. Then, the gate valve62is closed.

Next, the wafer W is loaded into the load-lock module21by the transfer robot70. When the wafer W is loaded into the load-lock module21, the load-lock module21is sealed and exposed to the atmosphere. Then, the inner space of the load-lock module21communicates with the inner space of the loader module30.

Next, the wafer W is held by the transfer device40and is returned to the desired hoop31to be accommodated from the load-lock module21through the loader module30. This ends the wafer processing using the plasma processing system1.

Next, the processing module60will be described with reference toFIGS.3to5.FIG.3is a vertical cross-sectional view showing a schematic configuration of the processing module60.FIG.4is a partially enlarged view ofFIG.3.FIG.5is an enlarged cross-sectional view of a part different fromFIG.4in a circumferential direction of a wafer support101(described later).

As shown inFIG.3, the processing module60includes the chamber100serving as a processing container, a gas supply140, a radio frequency (RF) power supply150, and an exhaust system160. The processing module60also includes a voltage application unit120(seeFIG.4) and a gas supply130(seeFIG.5). The processing module60further includes the wafer support101serving as a substrate support and an upper electrode102.

The chamber100has an inner space that is configured to be decompressed, and defines a processing space100sin which the plasma is generated. Further, the wafer support101and the like are provided in the chamber100. For example, aluminum can be used as a material of the chamber100. Further, the chamber100is connected to a ground potential.

For example, the wafer support101is disposed in a lower region of the chamber100. The upper electrode102is disposed above the wafer support101and may function as a part of a ceiling of the chamber100.

The wafer support101is configured to support the wafer W. In one embodiment, the wafer support101includes a lower electrode103, an electrostatic chuck104, a support105, an insulator106, a lifter107, and a lifter108. The wafer support101is also configured to support the edge ring E. The wafer support101may or may not include the edge ring E as a constituent member thereof.

The lower electrode103is made of a conductive material such as aluminum. In one or more embodiments of the present application, a flow path109of a temperature-controlled fluid is formed in the lower electrode103. The temperature-controlled fluid is supplied to the flow path109from a chiller unit (not shown) provided outside the chamber100. The temperature-controlled fluid supplied to the flow path109returns to the chiller unit. For example, the wafer support101(specifically, the electrostatic chuck104), the wafer W, or the edge ring E can be cooled to a predetermined temperature by circulating, for example, low-temperature brine as the temperature-controlled fluid through the flow path109. For example, the wafer support101(specifically, the electrostatic chuck104), the wafer W, or the edge ring E can be heated to a predetermined temperature by circulating, for example, high-temperature brine as the temperature-controlled fluid through the flow path109.

When a temperature control mechanism is provided in the wafer support101, a form of the temperature control mechanism is not limited to the flow path109and may be, for example, another form such as a resistance heating type heater. Further, a member in which the temperature control mechanism is disposed in the wafer support101is not limited to the lower electrode103and may be another member.

The electrostatic chuck104is a member configured to electrostatically attract at least the edge ring E and is provided on the lower electrode103. The electrostatic chuck104may also be configured to electrostatically attract the wafer W. In one or more embodiments of the present application, a central portion of the electrostatic chuck104constitutes a substrate stage. Further, in one or more embodiments of the present application, in the electrostatic chuck104, an upper surface of the central portion is formed to be higher than an upper surface of a peripheral portion. In one or more embodiments of the present application, the wafer W is placed on an upper surface104aof the central portion of the electrostatic chuck104, and the edge ring E is placed on an upper surface104bof the peripheral portion of the electrostatic chuck104. That is, in one or more embodiments of the present application, the upper surface104aof the central portion of the electrostatic chuck104serves as a wafer placing surface as a substrate placing surface on which the wafer W is placed, and the upper surface104bof the peripheral portion of the electrostatic chuck104serves as a ring placing surface on which the edge ring E is placed to surround the substrate placing surface.

The edge ring E is a member disposed to surround the wafer W and is specifically a member disposed to surround the wafer W placed on the electrostatic chuck104. In one or more embodiments of the present application, the edge ring E is disposed to surround the central portion having a higher position of the upper surface than the peripheral portion in the electrostatic chuck104. The edge ring E is formed to have an annular shape in plan view. Si, SiO2, or the like is used as a material of the edge ring E.

An electrode110for electrostatically attracting the wafer W to the upper surface104aof the central portion may be provided in the central portion of the electrostatic chuck104. Further, an electrode111for electrostatically attracting the edge ring E to the upper surface104bof the peripheral portion is provided in the peripheral portion of the electrostatic chuck104. The electrode111is, for example, a bipolar electrode that includes a pair of electrodes111aand111bformed at positions different from each other.

The electrostatic chuck104has a configuration in which the electrodes110and111are interposed between insulating members made of, for example, an insulating material.

As shown inFIG.4, the voltage application unit120is connected to the electrode111to generate an electric force (specifically, for example, a coulomb force) for electrostatically attracting the edge ring E. When the electrode111is a bipolar electrode, any one of voltages of polarities different from each other or voltages of the same polarity are configured to be selectively applied to the pair of electrodes111aand111bfrom the voltage application unit120.

The voltage application unit120includes, for example, two direct-current power supplies121aand121band two switches122aand122b.

The direct-current power supply121ais connected to the electrode111athrough the switch122aand selectively applies a positive voltage or a negative voltage for electrostatically attracting the edge ring E to the electrode111a.

The direct-current power supply121bis connected to the electrode111bthrough the switch122band selectively applies a positive voltage or a negative voltage for electrostatically attracting the edge ring E to the electrode111b.

The voltage application unit120may include a direct-current power supply121cand a switch122c.

The direct-current power supply121cis connected to the electrode110through the switch122cand applies a voltage for electrostatically attracting the wafer W to the electrode110.

In one or more embodiments of the present application, the central portion of the electrostatic chuck104provided with the electrode110and the peripheral portion of the electrostatic chuck104provided with the electrode111are integrated with each other. However, the central portion and the peripheral portion may be separate bodies.

Further, in one or more embodiments of the present application, the electrode111for attracting and holding the edge ring E is a bipolar electrode. However, the electrode111may be a unipolar electrode.

Further, for example, the central portion of the electrostatic chuck104is formed to have a diameter smaller than a diameter of the wafer W. When the wafer W is placed on the upper surface104aof the central portion of the electrostatic chuck104, a peripheral portion of the wafer W horizontally protrudes outward from the central portion of the electrostatic chuck104.

Further, the edge ring E has a stepped portion formed on an upper portion thereof, and an upper surface of an outer peripheral portion of the edge ring E is formed to be higher than an upper surface of an inner peripheral portion of the edge ring E. The inner peripheral portion of the edge ring E is positioned below the peripheral portion of the wafer W that horizontally protrudes outward from the central portion of the electrostatic chuck104. In other words, an inner diameter of the edge ring E is smaller than an outer diameter of the wafer W.

The support105is a member formed to have an annular shape in plan view using, for example, an insulating material such as quartz, and is disposed to surround the lower electrode103and the electrostatic chuck104.

A gas discharge hole (not shown) may be formed in the upper surface104aof the central portion of the electrostatic chuck104to discharge a heat transfer gas into a gap between a rear surface of the placed wafer W and the wafer W. The heat transfer gas from a gas supply (not shown) is supplied through the gas discharge hole. The gas supply may include one or more gas sources and one or more pressure controllers. In one or more embodiments of the present application, for example, the gas supply is configured to supply the heat transfer gas from the gas source to the gas supply hole through the pressure controller.

Further, as shown inFIG.5, a gas discharge hole104cis formed in the upper surface104bof the peripheral portion of the electrostatic chuck104. Specifically, one end of the gas discharge hole104cis open in the upper surface104bof the peripheral portion of the electrostatic chuck104. For example, a plurality of gas discharge holes104care provided along a circumferential direction of the electrostatic chuck104. The gas discharge hole104csupplies the heat transfer gas such as a helium gas to a space between a rear surface of the edge ring E placed on the upper surface104bof the peripheral portion of the electrostatic chuck104and the upper surface104b. Further, an end portion of the gas discharge hole104copposite to the upper surface104bof the peripheral portion is connected to the gas supply130through a pipe133. The gas supply130may include one or more gas sources131and one or more flow controllers132. In one or more embodiments of the present application, for example, the gas supply130is configured to supply the heat transfer gas from the gas source131to the gas discharge hole104cthrough the flow rate controller132. Each flow rate controller132may include, for example, a mass flow controller or a pressure-controlled flow rate controller. The gas discharge hole104cand the pipe133may function as at least a part of a supply path for supplying a gas to the space between the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface, and the rear surface of the edge ring E.

The end portion of the gas discharge hole104copposite to the upper surface104bof the peripheral portion is also connected to the exhaust system160through a pipe161. Accordingly, air around the upper surface104bof the peripheral portion of the electrostatic chuck104can be exhausted through the gas discharge hole104c. That is, the gas discharge hole104ccan function as an exhaust hole for exhausting air around the ring placing surface including the upper surface104bof the peripheral portion of the electrostatic chuck104. Accordingly, in one or more embodiments of the present application, the gas discharge hole104cand the pipe161may function as at least a part of an exhaust path for exhausting air between the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface, and the rear surface of the edge ring E.

Further, in order to measure a pressure in the gap between the edge ring E electrostatically attracted to the upper surface104bof the peripheral portion and the upper surface104b, a pressure sensor134that measures a pressure in the supply path is provided for the electrostatic chuck104. The pressure sensor134is provided in, for example, the pipe133.

The pipe133may also be provided with a switching valve135that switches between executing and stopping of supply of the heat transfer gas via the gas supply130. Similarly, the pipe161may be provided with a switching valve162that switches between executing and stopping of air exhaustion around the upper surface104bof the peripheral portion with the exhaust system160.

The insulator106inFIG.3is a member of a cylindrical shape formed of a ceramic material or the like and supports the support105. For example, the insulator106is formed to have an outer diameter equal to an outer diameter of the support105and supports a peripheral edge portion of the support105.

The lifter107is a member that is elevated with respect to the upper surface104aof the central portion of the electrostatic chuck104. The lifter107is formed to have a columnar shape using, for example, a ceramic material. When the lifter107is raised, an upper end thereof protrudes from the upper surface104aand can support the wafer W. The lifter107can transfer the wafer W between the wafer support101and the transfer arm71of the transfer robot70.

Three or more lifters107are provided at intervals from each other and are provided to extend in an up-down direction.

The lifter107is elevated by an actuator112. The actuator112includes, for example, a support member113that supports a plurality of lifters107, and a driving unit114that generates a driving force for elevating the support member113to elevate the plurality of lifters107. The driving unit114includes, for example, a motor (not shown) as a driving source that generates the driving force.

The lifter107is inserted into an insertion hole115having an upper end open to the upper surface104aof the central portion of the electrostatic chuck104. For example, the insertion hole115is formed to extend downward from the upper surface104aof the central portion of the electrostatic chuck104to reach a bottom surface of the lower electrode103.

The lifter108is an elevation member that is elevated with respect to the upper surface104bof the peripheral portion of the electrostatic chuck104, and is formed of, for example, a ceramic material. For example, the lifter108is formed to have a columnar shape except for its upper end portion (that is, a tip), and the upper end portion is formed to have a hemispherical shape. In one or more embodiments of the present application, the lifter108is configured such that an upper end thereof can protrude from an upper surface105aof the support105when the lifter108is raised.

Three or more lifters108are provided at intervals from each other along the circumferential direction of the electrostatic chuck104and are provided to extend in the up-down direction.

The lifter108is elevated by an actuator116. For example, the actuator116is provided for each lifter108and includes a support member117that movably supports the lifter108in the horizontal direction. For example, the support member117has a thrust bearing in order to movably support the lifter108in the horizontal direction. The actuator116also includes a driving unit118that generates a driving force for elevating the support member117to elevate the lifter108. The driving unit118includes, for example, a motor (not shown) as a driving source that generates the driving force.

In one or more embodiments of the present application, the lifter108is inserted into an insertion hole119having an upper end open to the upper surface105aof the support105. For example, the insertion hole119is formed to pass through the support105in the up-down direction.

The edge ring E can be transferred between the wafer support101and the transfer arm71of the transfer robot70by the lifter108.

Further, the lifter108and the actuator116constitute an elevation mechanism that elevates the edge ring E with respect to the ring placing surface.

The upper electrode102also functions as a gas supply, that is, a shower head, that discharges one or more gases from the gas supply140into the chamber100. In one or more embodiments of the present application, the upper electrode102has a gas inlet102a, a gas diffusion space102b, and a plurality of gas outlets102c. For example, the gas inlet102ais in fluid communication with the gas supply140and the gas diffusion space102b. The plurality of gas outlets102care in fluid communication with inner spaces of the gas diffusion space102band the chamber100. In one or more embodiments of the present application, the upper electrode102is configured to supply one or more gases such as processing gases from the gas inlet102ato the chamber100through the gas diffusion space102band the plurality of gas outlets102c.

The gas supply140may include one or more gas sources141and one or more flow rate controllers142. In one or more embodiments of the present application, for example, the gas supply140is configured to supply one or more gases from the respective corresponding gas sources141to the gas inlet102athrough the respective corresponding flow rate controllers142. Each flow rate controller142may include, for example, a mass flow controller or a pressure-controlled flow rate controller. Further, the gas supply140may include one or more flow rate modulation devices that modulate or pulsate flow rates of one or more gases.

The RF power supply150is configured to supply an RF power, for example, one or more RF signals, to one or more electrodes such as the lower electrode103, the upper electrode102, or both the lower electrode103and the upper electrode102. Accordingly, the plasma is generated from one or more processing gases supplied into the chamber100, that is, the processing space100s. Accordingly, the RF power supply150may function as at least a part of a plasma generator that generates the plasma in the chamber100. Specifically, the plasma generator is configured to generate the plasma from one or more gases in the chamber100. For example, the RF power supply150includes two RF generators151aand151band two matching circuits152aand152b. In one or more embodiments of the present application, the RF power supply150is configured to supply a first RF signal from the first RF generator151ato the lower electrode103through the first matching circuit152a. For example, the first RF signal may have a frequency within a range of 27 MHz to 100 MHz.

Further, in one or more embodiments of the present application, the RF power supply150is configured to supply a second RF signal from the second RF generator151bto the lower electrode103through the second matching circuit152b. For example, the second RF signal may have a frequency within a range of 400 kHz to 13.56 MHz. Further, instead of the second RF generator151b, a Direct Current (DC) pulse generator may be used.

Although it is not illustrated, other embodiments may be considered in the present disclosure. For example, in an alternative embodiment, the RF power supply150may be configured to supply the first RF signal from the RF generator to the lower electrode103, supply the second RF signal from another RF generator to the lower electrode103, and supply a third RF signal from still another RF generator to the lower electrode103. In addition, in another alternative embodiment, a DC voltage may be applied to the upper electrode102.

Further, in various embodiments, amplitudes of one or more RF signals (that is, the first RF signal, the second RF signal, and the like) may be pulsated or modulated. The amplitude modulation may include pulsating the RF signal amplitude between an ON state and an OFF state, or between two or more different ON states.

The exhaust system160may be connected to an exhaust port100eprovided, for example, at a bottom of the chamber100. The exhaust system160may include a pressure valve and a vacuum pump. The vacuum pump may include a turbo molecular pump, a roughing pump or a combination thereof.

Next, an example of the wafer processing performed by the processing module60will be described. In the processing module60, the wafer W is subjected to the plasma processing such as the etching processing.

The wafer W is first loaded into the chamber100by the transfer robot70, and the wafer

W is placed on the electrostatic chuck104by raising/elevating and lowering the lifter107. A direct-current voltage is then applied from the direct-current power supply121cto the electrode110of the electrostatic chuck104that thus electrostatically attracts and holds the wafer W. After the wafer W is loaded, the inner space of the chamber100is decompressed to a predetermined vacuum level by the exhaust system160.

The processing gas is subsequently supplied from the gas supply140to the processing space100sthrough the upper electrode102. Further, RF power HF for plasma generation is supplied from the RF power supply150to the lower electrode103to excite the processing gas to generate plasma. RF power LF for ion attraction may also be supplied from The RF power supply150. With the generated plasma, the wafer W is subjected to the plasma processing.

During the plasma processing, direct-current voltages are applied from the direct-current power supplies121aand121bto the electrode111of the electrostatic chuck104. Accordingly, the edge ring E is electrostatically attracted and held by the electrostatic chuck104. Further, during the plasma processing, the heat transfer gas is supplied, via the gas supply or the like, toward bottom surfaces of the wafer W and the edge ring E attracted and held by the electrostatic chuck104.

To end the plasma processing, the supply of the RF power HF from the RF power supply150and the supply of the processing gas from the gas supply140are stopped. When the RF power LF is supplied during the plasma processing, the supply of the RF power LF is also stopped. Subsequently, the attracting and holding the wafer W by the electrostatic chuck104is stopped. The supply of the heat transfer gas to the bottom surface of the wafer W may also be stopped.

Then, the wafer W is raised by the lifter107and separated from the electrostatic chuck104. During the separation, charge neutralization of the wafer W may be performed. The wafer W is unloaded from the chamber100by the transfer robot70, and a series of wafer processing ends.

EXAMPLE 1 OF INSTALLATION SEQUENCE

Next, an example of an installation sequence of the edge ring E in the processing module60executed by the plasma processing system1will be described.FIG.6is a flowchart showing Example 1 of the installation sequence of the edge ring E.FIGS.7to14are diagrams schematically showing the state of the processing module60when the installation sequence of the edge ring E is executed. InFIGS.7to14, a valve in an open state and the voltage application unit120in the ON state are shown in white, a valve in a closed state and the voltage application unit120in the OFF state are shown in black, and a pipe in which the gas flows is shown by a thick line. Further, inFIGS.7to14, the gas discharge hole104cthrough which gas has been exhausted is shown in black, the gas discharge hole104cin which the heat transfer gas is present is shown in gray, and the gas discharge hole104cin other states is shown in white. Each of the following steps is performed by the plasma processing system1under control and calculation of the controller80(specifically, the processor91) based on the program stored in the storage92.

For example, as shown inFIG.6, first, the edge ring E that is transferred into the chamber100by the transfer robot70and that is transferred to the elevation mechanism including the lifter108is lowered by the elevation mechanism and placed on the ring placement surface (step S1). Step S1is performed without the wafer W in the chamber100.

Specifically, in step S1, for example, the transfer robot70first loads the edge ring E in the accommodation module61into the chamber100of the processing module60that is an processing target of the edge ring E.

More specifically, for example, the edge ring E in the accommodation module61is held by the fork72of the transfer arm71of the transfer robot70. Further, in the processing module60that is the installation target, the exhaust system160exhausts air in the chamber100in a state where the gas is not discharged through the upper electrode102to create a high vacuum in the chamber100. Next, the corresponding gate valve62is open, and the fork72holding the edge ring E is inserted into the chamber100through a loading and unloading port (not shown). As shown inFIG.7, the edge ring E is transferred above the upper surface104bof the peripheral portion of the electrostatic chuck104and the upper surface105aof the support105by the fork72. At this time, the wafer W is not placed on the upper surface104aof the central portion of the electrostatic chuck104.

Subsequently, the edge ring E is transferred from the transfer robot70to the lifter108.

Specifically, all lifters108are raised, and the edge ring E is transferred from the fork72to the lifter108as shown inFIG.8. Then, the fork72is retracted from the chamber100, and the gate valve62is closed.

Next, the edge ring E is lowered by the elevation mechanism including the lifter108and placed on the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface.

Specifically, the lifter108is lowered until the upper end of the lifter108is accommodated in the insertion hole119. Accordingly, as shown inFIG.9, the edge ring E is placed on the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface.

After step S1, the edge ring E is vacuum-attracted to the ring placing surface (step S2). Specifically, without the wafer W in the chamber100, air around the ring placing surface is exhausted through the gas supply hole104cthat also functions as the exhaust hole.

More specifically, as shown inFIG.10, the switching valve162switches to the open state, and air around the upper surface104bof the peripheral portion of the electrostatic chuck104and the upper surface105aof the support105is exhausted through the gas discharge hole104cby the exhaust system160. In particular, air near the upper surface104bof the peripheral portion of the electrostatic chuck104is exhausted through the gas discharge hole104c. Accordingly, the edge ring E is vacuum-attracted to the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface.

Next, the placed edge ring E is electrostatically attracted to the ring placing surface (step S3). Specifically, a voltage is applied to the electrode111of the electrostatic chuck104without the wafer W in the chamber100, the edge ring E is placed on the ring placing surface, and air is being exhausted through the gas discharge hole104c.

More specifically, as shown inFIG.11, with the edge ring E placed on the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface, and air being exhausted through the gas discharge hole104c, the voltage application unit120switches to the ON state. Specifically, the direct-current power supplies121aand121bswitch to the ON state. Accordingly, a direct-current voltage is applied to the electrode111of the electrostatic chuck104. For example, direct-current voltages having polarities different from each other are applied to the electrodes111aand111b.

A voltage may be applied to the electrode111of the electrostatic chuck104after gas is exhausted through the gas supply hole104cand gas exhaustion is completed and stopped.

Next, the gas is supplied to the supply path such that the pressure in the supply path including the gas discharge hole104cis maintained to be higher than a pressure in the chamber100(step S4).

Specifically, without the wafer W in the chamber100, the gas exhaustion through the gas discharge hole104cis stopped, and a predetermined gas is discharged to the gap between the ring placing surface and the edge ring E through the gas discharge hole104c. The pressure in the gap is increased above the pressure in the chamber100.

At the end of step S4, the gas supply to the supply path, that is, the discharge of the predetermined gas through the gas discharge hole104c, is stopped.

In step S4, more specifically, as shown inFIG.12, the switching valve162switches to the closed state, and the air exhaustion by the exhaust system160through the gas discharge hole104cis stopped. Further, the switching valve135switches to the open state, and the heat transfer gas supplied from the gas supply130is discharged to the gap through the gas discharge hole104c. When the pressure in the gap reaches a target pressure (specifically, for example, when a measurement result of the pressure sensor134reaches the target pressure), the switching valve135switches to the closed state as shown inFIG.13, and the discharge of the heat transfer gas is stopped. The target pressure is, for example, the pressure in the gap during the plasma processing.

After the gas supply in step S4, the pressure in the supply path including the gas discharge hole104cis measured (step S5).

Specifically, in step S5, a pressure in the pipe133(more specifically, a pressure downstream of the switching valve135in the pipe133) is measured by the pressure sensor134after a predetermined time elapses from the stopping of the gas supply in step S4. The predetermined time is, for example, 10 seconds to 100 seconds, and this information is stored in advance in the storage92.

The pressure downstream of the switching valve135in the pipe133substantially coincides with the pressure in the gap between the ring placing surface and the edge ring E. Accordingly, step S5can be referred to as a step of measuring the pressure in the gap between the ring placing surface and the edge ring E.

The controller80determines a placing state of the edge ring E on the ring placing surface, that is, whether the placing state is appropriate, based on the measurement result in step S5(step S6).

Specifically, the controller80determines leaking of the predetermined gas from the gap based on the measurement result in step S5. More specifically, the controller80determines whether the pressure measured in step S5is less than a threshold as the determination of leaking of the predetermined gas from the gap. This threshold is set to, for example, 90 to 98% of the target pressure, and this information is stored in advance in the storage92.

When the placement state of the edge ring E on the ring placing surface is determine to be inappropriate in step S6, that is, when the predetermined gas is determined to have leaked from the gap (NO), the measurer73of the transfer robot70measures information relating to the misalignment amount of the edge ring E with respect to the electrostatic chuck104(step S7).

Specifically, when the predetermined gas is determined to have leaked from the gap, that is, when the pressure measured in step S5is less than the threshold, first, the gate valve62is open, and the fork72that is not holding the wafer W and the edge ring E is inserted into the chamber100. A distance from the distance sensor to the wafer support101is measured by the distance sensor included in the measurer73for each predetermined interval in the circumferential direction of the electrostatic chuck104and for each predetermined fine interval in a diameter direction of the electrostatic chuck104.

Then, the controller80calculates the misalignment amount of the edge ring E with respect to the electrostatic chuck104based on the measurement result of the measurer73(step S8).

Specifically, the controller80identifies a peripheral end of the central portion of the electrostatic chuck104and an inner peripheral end of the edge ring E for each predetermined interval related to the circumferential direction of the electrostatic chuck104based on the measurement result in step S7, and calculates a distance from the peripheral end of the central portion of the electrostatic chuck104to the inner peripheral end of the edge ring E. The controller80calculates the misalignment amount of the edge ring E with respect to the electrostatic chuck104(specifically, a distance from the center of the central portion of the electrostatic chuck104to the center of the edge ring E) based on a calculation result for each predetermined interval. The misalignment amount calculated here includes a direction of the misalignment.

Next, the controller80determines whether the misalignment amount calculated in step S8exceeds a threshold (step S9). This threshold is, for example, 200 μm, and this information is prestored in the storage92.

When a determination that the misalignment amount exceeds the threshold is made in step S9(YES), the position of the edge ring E on the ring placing surface is adjusted (step S10).

Specifically, the application of the voltage to the electrode111of the electrostatic chuck104is stopped, and the edge ring E is raised by the elevation mechanism including the lifter108. Then, the edge ring E is transferred to the transfer robot70.

More specifically, the application of the direct-current voltage from the voltage application unit120to the electrode111is stopped, and the fork72of the transfer robot70is retracted from a position above the wafer support101. Next, charge neutralization of the edge ring E is performed. Then, all the lifters108are raised, and the edge ring E is transferred from the wafer support101to the lifter108. Next, the fork72of the transfer arm71is moved to a position between the wafer support101and the edge ring E supported by the lifter108. Next, all the lifters108are lowered, and the edge ring E is transferred from the lifter108to the fork72.

Then, the edge ring E is moved to a position based on the misalignment amount calculated in step S8.

Specifically, the fork72is moved to a corrected position based on the misalignment amount calculated in step S8. The corrected position is calculated in advance by the controller80based on the misalignment amount calculated in step S8, such that the misalignment amount approaches zero.

Then, after the edge ring E is returned to the elevation mechanism including the lifter108, the edge ring E is lowered by the elevation mechanism and placed on the ring placing surface again.

Specifically, all the lifters108are raised again, and the edge ring E is transferred from the fork72to the lifter108. Next, the fork72is retracted from the chamber100, and the gate valve62is closed.

Then, the edge ring E is lowered by the elevation mechanism including the lifter108and placed on the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface.

Specifically, the lifter108is lowered until the upper end of the lifter108is accommodated in the insertion hole119. Accordingly, the edge ring E is placed on the upper surface104bof the peripheral portion of the electrostatic chuck104, which is the ring placing surface.

After step S10, the sequence returns to step S2, and the vacuum-attraction or the like of the edge ring E is performed.

When a determination that the placing state of the edge ring E on the ring placing surface is appropriate is made in step S6, that is, when a determination that leaking of the predetermined gas from the gap does not occur is made (specifically, when the pressure in the gap measured in step S5is greater than or equal to the threshold) (YES), step S11similar to step S7is performed. Accordingly, the measurer73measures the information relating to the misalignment amount of the edge ring E with respect to the electrostatic chuck104.

Then, as in step S8, the controller80calculates the misalignment amount of the edge ring E with respect to the electrostatic chuck104based on the measurement result of the measurer73(step S12).

Next, the controller80determines whether the misalignment amount calculated in step S12is less than or equal to the threshold (step S13).

When a determination that the misalignment amount is less than or equal to the threshold is made in step S13(YES), processing of stabilizing the electrostatic attraction of the edge ring E is performed (step S14).

Specifically, for example, an electrostatic attraction force of the edge ring E is increased by generating the plasma from the processing gas in the chamber100and changing a charging state of the edge ring E using the plasma.

This completes the sequence.

Meanwhile, when a determination that the misalignment amount exceeds the threshold is made in step S13(NO), the position of the edge ring E on the ring placing surface is adjusted without the wafer W in the chamber100, as in step S10(step S16).

After step S16, the sequence returns to step S2, and the vacuum-attraction or the like of the edge ring E is performed.

When a determination that the misalignment amount does not exceed the threshold is made in step S9(NO), damage to at least either the edge ring E or the electrostatic chuck104, clinging of a foreign object to the upper surface104bof the peripheral portion of the electrostatic chuck104, and the like are expected. Thus, the operation of the entirety or a part (for example, only the corresponding processing module60) of the plasma processing system1is stopped (step S17). Then, the sequence ends. At the end, an alarm may be sounded, or the worker may be notified.

When a determination that the misalignment amount does not exceed the threshold is made in step S9(NO), the edge ring E may be temporarily removed from the wafer support101and then placed on the wafer support101again. Then, the steps from step S2may be repeated. Further, after the edge ring E is unloaded from the chamber100, the steps from step S1may be performed for a new edge ring E.

EXAMPLE 2 OF INSTALLATION SEQUENCE

In Example 1 of the installation sequence, step S2is performed after step S1. However, step S2may be performed in parallel with step S1.

Specifically, after the edge ring E is transferred to the lifter108in step S1, gas around the ring placing surface may be exhausted through the gas discharge hole104c, which also functions as the exhaust hole, in step S2before the edge ring E is lowered and placed on the ring placing surface.

EXAMPLE 3 OF INSTALLATION SEQUENCE

FIG.15is a flowchart showing Example 3 of the installation sequence of the edge ring E.

In Example 1 of the installation sequence, in step S1, the exhaust system160exhausts air in the chamber100in a state where the gas is not discharged through the upper electrode102, and in a state where a high vacuum is formed in the chamber100, the edge ring E is transferred into the chamber100, and the edge ring E is placed on the ring placing surface.

Meanwhile, in the present example, step S21described below is performed instead of step S1as shown inFIG.15. In step S21, the gas is discharged into the processing space100sthrough the upper electrode102, and air in the chamber100is exhausted by the exhaust system160. In a state where a quasi-high vacuum (for example, several hundred mTorr) is formed in the chamber100, the edge ring E is transferred into the chamber100, and the edge ring E is placed on the ring placing surface.

The gas may be discharged into the processing space100sthrough the upper electrode102as described above, or may be discharged from a gas introduction port (not shown) without passing through the upper electrode102.

In step S21, specifically, for example, first, in the processing module60which is the installation target of the edge ring E, an inert gas such as a nitrogen gas is supplied from the gas supply140into the processing space100sthrough the upper electrode102, and air in the chamber100is exhausted by the exhaust system160. Accordingly, the pressure in the chamber100is adjusted to a quasi-high vacuum having a higher vacuum level than the inner space of the transfer module50. Then, the corresponding gate valve62is open, and the fork72holding the edge ring E is inserted into the chamber100through the loading and unloading port (not shown). The edge ring E is transferred above the upper surface104bof the peripheral portion of the electrostatic chuck104and the upper surface105aof the support105by the fork72. Subsequent processing in step S21is similar to step S2.

After step S21, steps S2and S3are performed in a state where the pressure in the chamber100is adjusted to a quasi-high vacuum having a higher vacuum level than the inner space of the transfer module50.

Further, after steps S2and S3, the discharge of the gas into the processing space100sthrough the upper electrode102is stopped, and as in step S4, the pressure in the supply path including the gas discharge hole104cis increased in a state where the pressure in the chamber100is set to a high vacuum (step S22). The pressure in the supply path including the gas discharge hole104cmay be increased in a state where the pressure in the chamber100is set to a quasi-high vacuum, without stopping the discharge of the gas into the processing space100s.

After step S22, steps from step S5of Example 1 of the installation sequence are performed.

EXAMPLE 4 OF INSTALLATION SEQUENCE

In Example 3 of the installation sequence, step S2is performed after step S21in a state where the pressure in the chamber100is adjusted to a quasi-high vacuum having a higher vacuum level than the inner space of the transfer module50. However, step S2may be performed in parallel with step S21, as in Example 2 of the installation sequence.

EXAMPLE 5 OF INSTALLATION SEQUENCE

FIG.16is a flowchart showing Example 5 of the installation sequence of the edge ring E.

In Example 1 of the installation sequence, in step S3, the edge ring E is electrostatically attracted in a state where the plasma is not generated in the chamber100.

Meanwhile, in the present example, as shown inFIG.16, step S31described below is performed instead of step S3after steps S1and S2of Example 1 of the installation sequence are performed in order. In step S31, the gas for plasma generation is discharged into the processing space100sthrough the upper electrode102, and air in the chamber100is exhausted by the exhaust system160. Further, the RF power HF for plasma generation is supplied from the RF power supply150to, for example, the lower electrode103. Accordingly, the gas in the processing space100sis excited to generate the plasma. Although an example in which the RF power HF for plasma generation is supplied to the lower electrode103has been described, the present disclosure is not limited to this, and the RF power HF may be supplied to the upper electrode102. Then, as in step S3, a voltage is applied to the electrode111of the electrostatic chuck104without the wafer W in the chamber100, the edge ring E is placed on the ring placing surface, and gas is being exhausted through the gas discharge hole104c. The edge ring E is electrostatically attracted to the ring placing surface.

After step S31, steps from step S4of Example 1 of the installation sequence are performed.

EXAMPLE 6 OF INSTALLATION SEQUENCE

In Example 5 of the installation sequence, step S2is performed after step S1. However, step S2may be performed in parallel with step S1as in Example 2 of the installation sequence.

MODIFICATION EXAMPLES OF EXAMPLES 5 AND 6 OF INSTALLATION SEQUENCE

Step S21of Example 3 of the installation sequence may be performed instead of step S1of Examples 5 and 6 of the installation sequence, and after step S21, step S2may be performed in a state where the pressure in the chamber100is adjusted to a quasi-high vacuum having a higher vacuum level than the inner space of the transfer module50.

EXAMPLE 7 OF INSTALLATION SEQUENCE

FIG.17is a flowchart showing Example 7 of the installation sequence of the edge ring E.

In Example 1 of the installation sequence and the like, when a determination that the placing state of the edge ring E is appropriate is made in step S6(YES), step S11similar to step S7is performed, and the measurement unit73measures the information related to the misalignment amount of the edge ring E with respect to the electrostatic chuck104.

Meanwhile, in the present example, as shown inFIG.17, when a determination that the placing state of the edge ring E is appropriate is made in step S6(YES), step S11is not performed, and processing of stabilizing the electrostatic attraction of the edge ring E in step S14is performed.

MAIN EFFECTS OF EXAMPLES 1 TO 7 OF INSTALLATION SEQUENCE

In Examples 1 to 7 of the installation sequence, a step of lowering the edge ring E that is transferred into the chamber100by the transfer robot70and that is transferred to the elevation mechanism including the lifter108, via the elevation mechanism and placing the edge ring E on the ring placing surface, and a step of electrostatically attracting the placed edge ring E to the ring placing surface are performed. Further, in Examples 1 to 7 of the installation sequence, after the step of the electrostatic attraction, a step of supplying the gas to the supply path to maintain the pressure in the supply path including the gas discharge hole104cto be higher than the pressure in the chamber100, a step of measuring the pressure in the supply path, and a step of determining the placing state of the edge ring E based on the measured pressure are performed. In one or more embodiments of the present application, the placing state of the edge ring E is determined in such a manner. Thus, when the placing state of the edge ring Eis not appropriate, the edge ring E can be accurately placed on the electrostatic chuck104by, for example, adjusting the position of the edge ring E on the ring placing surface by the transfer robot.

Further, in Examples 1 to 7 of the installation sequence, a step of vacuum-attracting the edge ring E to the ring placing surface is performed before the electrostatic attraction of the edge ring E placed on the ring placing surface. Thus, the gas present in the gap between the ring placing surface and the edge ring E can be reduced when the edge ring E is electrostatically attracted to the ring placing surface. Accordingly, when the edge ring E is electrostatically attracted to the ring placing surface, misaligning of the edge ring E with respect to the electrostatic chuck104because of the gas present in the gap acting as an obstacle can be suppressed.

Further, in Examples 1 to 7 of the installation sequence, in determining deviation of the edge ring E, whether leaking of the heat transfer gas occurs when the heat transfer gas is supplied to the gap during the plasma processing can be checked before the plasma processing. When the heat transfer gas leaks during the plasma processing, it is difficult to, for example, appropriately adjust the temperature of the edge ring E through the electrostatic chuck104and through the heat transfer gas. Meanwhile, in Examples 1 to 7 of the installation sequence, as described above, since whether the heat transfer gas leaks during the plasma processing can be checked in advance, the difficulty of appropriately adjusting the temperature of the edge ring E and the like can be suppressed.

EXAMPLE 8 OF INSTALLATION SEQUENCE

FIG.18is a flowchart showing Example 8 of the installation sequence of the edge ring E.

In Example 1 of the installation sequence, after the edge ring E is electrostatically attracted to the ring placing surface in step S3, the heat transfer gas is supplied to the supply path including the gas discharge hole104c, that is, the space between the ring placing surface and the rear surface of the edge ring E, in step S4. Next, steps S5and S6are performed, and the placing state of the edge ring E is determined. Then, in step S7or step S11, the measurement unit73of the transfer robot70measures the information related to the misalignment amount of the edge ring E with respect to the electrostatic chuck104.

Meanwhile, in the present example, as shown inFIG.18, after the edge ring E is electrostatically attracted to the ring placing surface in step S3, step S11is performed, and the measurement unit73measures the information related to the misalignment amount of the edge ring E with respect to the electrostatic chuck104.

After step S11, steps from step S12of Example 1 of the installation sequence are performed.

Specifically, in step S12, the controller80calculates the misalignment amount of the edge ring E with respect to the electrostatic chuck104based on the measurement result of the measurement unit73.

Next, the controller80determines whether the misalignment amount calculated in step S12is less than or equal to the threshold value (step S13). When a determination that the misalignment amount is less than or equal to the threshold value is made in step S13(YES), processing of stabilizing the electrostatic attraction of the edge ring E is performed (step S14).

EXAMPLE 9 OF INSTALLATION SEQUENCE

In Example 8 of the installation sequence, step S2is performed after step S1as in Example 1 of the installation sequence. However, step S2may be performed in parallel with step S1.

EXAMPLE 10 OF INSTALLATION SEQUENCE

Step S21of Example 3 of the installation sequence may be performed instead of step S1of Examples 8 and 9 of the installation sequence, and after step S21, steps S2and S3may be performed in a state where the pressure in the chamber100is adjusted to a quasi-high vacuum having a higher vacuum level than the inner space of the transfer module50.

EXAMPLE 11 OF INSTALLATION SEQUENCE

After steps S1and S2of Examples 8 and 9 of the installation sequence, step S31of Example 5 of the installation sequence may be performed instead of step S3, and the edge ring E may be electrostatically attracted in a state where the plasma is generated in the chamber100.

EXAMPLE 12 OF INSTALLATION SEQUENCE

Before the electrostatic attraction of the edge ring E in step S3and step S31in Examples 8 to 11 of the installation sequence, the measurement unit73may measure the information related to the misalignment amount of the edge ring E with respect to the electrostatic chuck104, as in step S11. Then, before the electrostatic attraction of the edge ring E in step S31, the controller80may calculate the misalignment amount of the edge ring E with respect to the electrostatic chuck104based on the measurement result of the measurement unit73, as in step S12.

That is, steps S11and S12may be performed before the electrostatic attraction of the edge ring E in steps S3and S31in Examples 8 to 11 of the installation sequence.

MAIN EFFECTS OF EXAMPLES 8 TO 12 OF INSTALLATION SEQUENCE

In Examples 8 to 12 of the installation sequence, after the step of electrostatically attracting the edge ring E to the ring placing surface, the measurement unit73provided in the fork72of the transfer robot70measures the information related to the misalignment amount of the edge ring E with respect to the electrostatic chuck104. Thus, the actual misalignment amount of the edge ring E installed in Examples 8 to 12 of the installation sequence with respect to the electrostatic chuck104can be calculated, that is, acquired. In one or more embodiments of the present application, the misalignment amount of the edge ring E is acquired in such a manner. Thus, when the misalignment amount of the edge ring E with respect to the electrostatic chuck104is large, the edge ring E can be accurately placed by, for example, adjusting the position of the edge ring E on the ring placing surface. Further, performing the plasma processing with a large misalignment amount can be suppressed.

Further, in Examples 8 to 12 of the installation sequence, as in Examples 1 to 7 of the installation sequence, the gas present in the gap between the ring placing surface and the edge ring E can be reduced when the edge ring E is electrostatically attracted to the ring placing surface. Accordingly, when the edge ring E is electrostatically attracted to the ring placing surface, misaligning of the edge ring E with respect to the electrostatic chuck104because of the gas present in the gap acting as an obstacle can be suppressed.

MAIN EFFECTS OF EXAMPLES 5, 6, 11, AND 12 OF INSTALLATION SEQUENCE

In Examples 5, 6, 11, and 12 of the installation sequence, in step S31, the edge ring E is electrostatically attracted in a state where the plasma is generated in the chamber100. Accordingly, since charges are supplied from the plasma in the chamber100to the edge ring E on the ring placing surface, the edge ring E can be electrostatically attracted more strongly.

MODIFICATION EXAMPLES OF EXAMPLES 1 TO 7 OF INSTALLATION SEQUENCE

In step S4or step S22, the predetermined gas supplied to the gap between the ring placing surface and the edge ring E is the heat transfer gas. However, for example, a nitrogen gas other than the heat transfer gas may be used.

When a determination that the placing state of the edge ring E is not appropriate is made in step S6(NO), step S17may be performed without performing steps S7to S10, and the operation of the entirety or a part of the plasma processing system1may be stopped.

MODIFICATION EXAMPLES OF EXAMPLES 8 TO 12 OF INSTALLATION SEQUENCE

When a determination that the misalignment amount is less than or equal to the threshold value is made in step S13(YES), steps S4to S6of Example 1 of the installation sequence may be performed before step S14is performed. At this time, when a determination that the placing state of the edge ring E is not appropriate is made in step S6(NO), the edge ring E may be temporarily removed from the wafer support101and then placed on the wafer support101again. Then, the steps from step S2may be repeated. When a determination that the placing state of the edge ring E is not appropriate is made in step S6(NO), step S17may be performed instead of this, and the operation of the entirety or a part of the plasma processing system1may be stopped.

MODIFICATION EXAMPLE OF EXAMPLE 12 OF INSTALLATION SEQUENCE

Step S13, that is, determining whether the misalignment amount calculated in step S12is less than or equal to the threshold value, may be performed before the electrostatic attraction of the edge ring E in step S3or the like and after step S11and step S12. Here, when a determination that the misalignment amount is less than or equal to the threshold value is made, the steps from the step of electrostatically attracting the edge ring E, such as step S3, are performed. Meanwhile, when a determination that the misalignment amount exceeds the threshold value is made, for example, the sequence may return to step S2after the position of the edge ring E is adjusted in step S16.

MODIFICATION EXAMPLES OF EXAMPLES 3, 4, AND 10 OF INSTALLATION SEQUENCE

In Examples 3, 4, and 10 of the installation sequence, an inert gas such as a nitrogen gas is supplied into the processing space100s, and air in the chamber100is exhausted by the exhaust system160. Accordingly, the pressure in the chamber100is adjusted to a quasi-high vacuum. After the adjustment, the gate valve62is open, and the edge ring E is loaded into the chamber100. Instead, the pressure in the chamber100may be adjusted to a quasi-high vacuum after loading the edge ring E into the chamber100and closing the gate valve62.

MODIFICATION EXAMPLES OF EXAMPLES 1 TO 12 OF INSTALLATION SEQUENCE

In the above examples, when leaking from the gap between the ring placing surface and the edge ring E occurs in step S6, or when the misalignment amount calculated in step S12exceeds the threshold value in step S13of Example 8 of the installation sequence, the operation of the entirety or a part (for example, only the corresponding processing module60) of the plasma processing system1may be stopped.

Further, the step of vacuum-attracting the edge ring E in step S2may be omitted.

MODIFICATION EXAMPLE OF PLASMA PROCESSING APPARATUS

Unlike Examples 1 to 7 of the installation sequence, the pressure sensor134is not used in Examples 8 to 12 of the installation sequence. Accordingly, when Examples 8 to 12 of the installation sequence are adopted, the pressure sensor134may be omitted.

Although the measurement unit73includes the distance sensor, the measurement unit73may include a camera instead of the distance sensor as long as the information related to the misalignment amount of the edge ring E with respect to the electrostatic chuck104can be measured.

Further, although the gas exhaustion through the gas discharge hole104calso serving as the exhaust hole and the air exhaustion in the chamber100, that is, the processing space100s, are performed by the common exhaust system160, the air exhaustion may be performed by exhaust systems different from each other.

Further, the exhaust hole and the gas discharge hole104cmay be individually provided. That is, the exhaust path including the exhaust hole for exhausting air between the rear surface of the edge ring E and the ring placing surface and the supply path including the gas discharge hole104cmay be individually provided.

In addition to the edge ring E, a cover ring may be placed on the wafer support used in the plasma processing apparatus to cover an outer surface of the edge ring. The technique of the present disclosure can also be applied to this case.

FIG.19is a partially enlarged view for describing an example of a wafer support on which a cover ring CA is configured to be placed in addition to an edge ring EA.

Hereinafter, a wafer support101A inFIG.19will be mainly described based on its differences from the wafer support101shown inFIG.3or the like.

Similar to the wafer support101shown inFIG.3or the like, the wafer support101A inFIG.19not only includes the electrostatic chuck104, the insulator106, and the lifter107but also a lower electrode103A, a support105A, and a lifter108A. Both of the edge ring EA and the cover ring CA are configured to be placed on the wafer support101A.

A lower outer peripheral portion of the lower electrode103A and an upper inner peripheral portion of the support105A are formed to overlap with each other in plan view. Further, the lower electrode103A and the support105A are provided with an insertion hole119A into which the lifter108A is inserted. The insertion hole119A is formed to extend downward from an upper surface105Aa of an inner peripheral portion of the support105A to a bottom surface of the lower outer peripheral portion of the lower electrode103A.

The electrostatic chuck104is provided to be placed on the lower electrode103A. The edge ring EA is placed on the upper surface104bof the peripheral portion of the electrostatic chuck104, and the cover ring CA is placed on the upper surface105Aa of the support105A. A height of the upper surface105Aa of the support105A and a height of an upper surface of the lower electrode103A substantially coincide with each other.

The edge ring EA is formed to have a larger outer diameter than the electrostatic chuck104. Accordingly, when the edge ring EA is placed on the upper surface104bof the peripheral portion of the electrostatic chuck104, a peripheral portion of the edge ring EA horizontally protrudes outward from the peripheral portion of the electrostatic chuck104.

The cover ring CA is a member disposed to cover an outer surface of the edge ring EA. Similar to the edge ring EA, the cover ring CA is also formed to have an annular shape in plan view. In one or more embodiments of the present application, the cover ring CA has a projection CA1that protrudes inward in a diameter direction at a bottom thereof.

Further, the cover ring CA has a through hole CA2into which the lifter108A is inserted, at a position corresponding to each lifter108A. The through hole CA2passes through the cover ring CA from a bottom surface of the cover ring CA to the edge ring EA. The through hole CA2is provided in a part (specifically, for example, the projection CA1) that overlaps with the peripheral portion of the edge ring EA and that overlaps with an inner peripheral portion of the cover ring CA in plan view.

The lifter108A is configured to protrude from the upper surface105Aa of the inner peripheral portion of the support105A and is elevated such that an amount of protrusion from the upper surface105Aa is adjustable. Specifically, the lifter108A is configured to protrude from a position overlapping with the edge ring EA and the cover ring CA in plan view on the upper surface105Aa of the inner peripheral portion of the support105A. The insertion hole119A into which the lifter108A is inserted is formed at a position overlapping with the edge ring EA and the cover ring CA in plan view.

Similar to the lifter108inFIG.3or the like, three or more lifters108A are provided at intervals from each other along the circumferential direction of the electrostatic chuck104.

Further, the lifter108A has a first engaging portion108Aa and a second engaging portion108Ab.

The first engaging portion108Aa is configured with an upper portion of the lifter108A. For example, the first engaging portion108Aa is formed to have a columnar shape except for its upper end portion (that is, a tip), and the upper end portion is formed to have a hemispherical shape. The first engaging portion108Aa protrudes upward from the through hole CA2of the cover ring CA and engages with the edge ring EA. When the lifter108A is raised, the first engaging portion108Aa passes through the through hole CA2of the cover ring CA and comes into contact with a bottom surface of the edge ring EA. Accordingly, the edge ring EA is configured to be supported from its bottom surface.

The second engaging portion108Ab is positioned below the first engaging portion108Aa and engages with the cover ring CA. The second engaging portion108Ab comes in contact with the bottom surface of the cover ring CA without passing through the through hole CA2of the cover ring CA. Accordingly, the cover ring CA is configured to be supported from its bottom surface.

Further, the second engaging portion108Ab is connected to a base end side of the first engaging portion108Aa along an axial direction of the lifter108A. Further, the second engaging portion108Ab has a protruding portion108Ac that protrudes outward from a periphery of the first engaging portion108Aa, at a position connected to the first engaging portion108Aa.

Specific shapes of the first engaging portion108Aa, the second engaging portion108Ab, and the protruding portion108Ac are not particularly limited. For example, the first engaging portion108Aa, the second engaging portion108Ab, and the protruding portion108Ac may be cylindrical members and coaxial with each other.

The actuator116elevates the cover ring CA by elevating the lifter108A of which the second engaging portion108Ab is engaged with the cover ring CA.

The actuator116also elevates the edge ring EA by elevating the lifter108A of which the first engaging portion108Aa is engaged with the edge ring EA.

In the shown example, in a state where the lifter108A is most lowered, the second engaging portion108Ab is not positioned in the insertion hole119A. However, the second engaging portion108Ab may be positioned in the insertion hole119A. In this case, a sleeve (not shown) may be provided in a hole of the lower electrode103A constituting the insertion hole119A. The lifter108A is inserted into the sleeve, and the lifter108A is fitted to be positioned with respect to the lower electrode103A. Accordingly, the lifter108A is positioned with respect to the electrostatic chuck104. By this positioning, the edge ring EA and the cover ring CA supported by the lifter108A are also positioned.

When the wafer support101A is used, installation of the edge ring EA may be performed with the edge ring EA alone or at the same time as installation of the cover ring CA.

When the edge ring EA is installed alone, for example, a step of placing the edge ring EA on the wafer support101A is performed as follows.

That is, for example, the transfer robot70loads the edge ring EA in the accommodation module61into the chamber100of the processing module60that is an installation target of the edge ring EA.

Specifically, the edge ring EA in the accommodation module61is held by the fork72of the transfer robot70. Next, the fork72holding the edge ring EA is inserted into the chamber100of the processing module60, which is the installation target, through the loading and unloading port (not shown). The edge ring EA is transferred above the upper surface104bof the peripheral portion of the electrostatic chuck104by the fork72. At this time, the cover ring CA is in a state of being placed on the upper surface105Aa of the support105A.

Next, the edge ring EA is placed on the electrostatic chuck104from the transfer robot70.

Specifically, all lifters108A are raised, and the edge ring EA is transferred from the fork72to the first engaging portion108Aa of the lifter108A that has passed through the through hole CA2of the cover ring CA. At this time, the lifter108A is raised until the top of the first engaging portion108Aa reaches a predetermined height. Here, the predetermined height is a height at which the fork72does not interfere with the edge ring EA, the cover ring CA, and the like when the fork72is inserted and retracted between the cover ring CA placed on the support105A and the edge ring EA supported by the first engaging portion108Aa.

Next, the fork72is retracted from the chamber100. Further, the lifter108A is lowered. Accordingly, the edge ring EA is placed on the upper surface104bof the peripheral portion of the electrostatic chuck104.

Meanwhile, when the edge ring EA is installed at the same time as the cover ring CA, for example, a step of placing the edge ring EA on the wafer support101A is performed as follows.

That is, for example, the transfer robot70loads the cover ring CA supporting the edge ring EA in the accommodation module61into the chamber100of the processing module60that is an installation target of the edge ring EA and the cover ring CA.

Specifically, the cover ring CA supporting the edge ring EA in the accommodation module61is held by the fork72of the transfer robot70. Next, the fork72holding the cover ring CA is inserted into the chamber100of the processing module60, which is the installation target, through the loading and unloading port (not shown). The cover ring CA supporting the edge ring EA is transferred above the upper surface104bof the peripheral portion of the electrostatic chuck104and the upper surface105Aa of the support105A by the transfer arm71

Next, the edge ring EA and the cover ring are placed on the electrostatic chuck104and the support105A from the transfer robot70.

Specifically, all lifters108A are raised, and the edge ring EA is transferred from the cover ring CA held by the fork72to the first engaging portion108Aa of the lifter108A that has passed through the through hole CA2of the cover ring CA. Then, all lifters108A continue to be raised, and the cover ring CA is transferred from the fork72to the second engaging portion108Ab of the lifter108A. At this time, the lifter108A is raised until the top of the second engaging portion108Ab reaches a predetermined height. Here, the predetermined height is a height at which the fork72does not interfere with the cover ring CA and the like when the fork72is inserted and retracted between the upper surface104aof the central portion of the electrostatic chuck104and the cover ring CA supported by the second engaging portion108Ab.

Next, the fork72is retracted from the chamber100. Further, the lifter108A is lowered. Accordingly, the edge ring EA and the cover ring CA are placed on the upper surface104bof the peripheral portion of the electrostatic chuck104and the upper surface105Aa of the support105A. Specifically, first, the cover ring CA is placed on the upper surface105Aa of the support105A, and then the edge ring EA is placed on the upper surface104bof the peripheral portion of the electrostatic chuck104.

The edge ring may be configured as follows. That is, the edge ring may be configured such that the edge ring moves (specifically, slides on the lifter) via its own weight or the like to be positioned with respect to the lifter even when the edge ring is misaligned with respect to the lifter immediately after being transferred to the lifter.

A recess EB1for positioning with respect to the lifter108A as described above is provided at a position corresponding to each lifter108A on a lower surface of an edge ring EB inFIG.20. The recess EB1has a flare shape that widens downward. When the edge ring EB is misaligned with respect to a plurality of lifters108A immediately after being transferred to the plurality of lifters108A, the edge ring EB moves with respect to the plurality of lifters108A such that an upper end portion of each lifter108A relatively slides along a recessed surface forming the recess EB1. Thus, the edge ring EB can be positioned with respect to the plurality of lifters108A.

When the edge ring EB is used, for example, a wafer support101B inFIG.20is used. The technique of the present disclosure can also be applied to a case where the wafer support101B inFIG.20is used.

Hereinafter, the wafer support101B will be mainly described based on its differences from the wafer support101A shown inFIG.19.

Similar to the wafer support101A, the wafer support101B not only includes the electrostatic chuck104, the lifter107, and the lifter108A but also a lower electrode103B, a support105B, an insulator106B, and a low thermal expansion member170.

The low thermal expansion member170is a member that is formed to have a plate shape and that has a lower coefficient of thermal expansion than the lower electrode103B, and is made of, for example, a ceramic material. The lower electrode103B is provided to be placed on the low thermal expansion member170.

In the wafer support101A, the lower electrode103A has a larger diameter than the electrostatic chuck104in plan view.

Meanwhile, in the wafer support101B, the lower electrode103B has substantially the same diameter as the electrostatic chuck104in plan view. Further, the low thermal expansion member170is formed to have a larger diameter than the electrostatic chuck104in plan view. That is, the low thermal expansion member170has an outer peripheral portion171that does not overlap with the lower electrode103B in plan view.

The support105B formed to have an annular shape in plan view is provided to be placed on the outer peripheral portion171of the low thermal expansion member170.

Further, a through hole172into which the lifter108A is inserted is provided in the outer peripheral portion171of the low thermal expansion member170.

Further, a sleeve member180is provided to be placed on the outer peripheral portion171of the low thermal expansion member170in accordance with the through hole172. Similar to the low thermal expansion member170, the sleeve member180also has a lower coefficient of thermal expansion than the lower electrode103B. The sleeve member180has a fixed portion181and a sleeve main body182.

The fixed portion181is fixed with respect to the low thermal expansion member170. For example, the fixed portion181is formed to extend outward from the sleeve main body182and is fixed to the low thermal expansion member170by a screw190. By fixing the fixed portion181with respect to the low thermal expansion member170, the sleeve member180is fixed with respect to the low thermal expansion member170. The sleeve member180is fixed at a gap with respect to the lower electrode103B to avoid contact with the thermally expanded lower electrode103B.

The sleeve main body182has a through hole182ainto which the lifter108A is inserted. The through hole182acommunicates with the through hole172of the low thermal expansion member170. By fitting between the sleeve main body182and the inserted lifter108A, the lifter108A is positioned with respect to the low thermal expansion member170to which the sleeve member180is fixed.

A recess105Bb is provided at a position corresponding to the through hole172in the support105B. The sleeve member180and the screw190are accommodated in the recess105Bb. The recess105Bb is provided such that the lifter108A inserted into the sleeve member180in the recess105Bb can protrude above the support105B. For example, the recess105Bb has an opening with respect to a space above the support105B, and an upper end portion of the sleeve member180is inserted into the opening.

In the wafer support101B, an insertion hole119B into which the lifter108A is inserted is configured with the through hole172of the low thermal expansion member170, the through hole182aof the sleeve member180, and the recess105Bb of the support105B.

Even in the wafer support101B, the cover ring CA is placed on an upper surface105Ba of the support105B. Further, a height of the upper surface105Ba of the support105B and a height of an upper surface of the lower electrode103B substantially coincide with each other.

The insulator106B is a member of a cylindrical shape formed of a ceramic material or the like and supports the support105B or the like by supporting the low thermal expansion member170. For example, the insulator106B is formed to have an outer diameter equal to an outer diameter of the low thermal expansion member170and supports a peripheral portion of the low thermal expansion member170.

When the wafer support101B is used, the sleeve member180is positioned with respect to the electrostatic chuck104and fixed to the low thermal expansion member170. Further, as described above, the low thermal expansion member170and the sleeve member180have a lower coefficient of thermal expansion than the lower electrode103B, and the sleeve member180is fixed at a gap with respect to the lower electrode103B as described above. Accordingly, even at a high temperature, a positional relationship between the lifter108A positioned in the sleeve member180and the electrostatic chuck104is less susceptible to an effect of thermal expansion of the lower electrode103B or the like. Thus, the edge ring EB positioned with respect to the lifter108A can be accurately installed at an appropriate position with reference to the electrostatic chuck104through the lifter108A even at a high temperature.

Further, in the wafer support101B, a diameter of the lower electrode103B in plan view can be reduced within a range greater than the diameter of the wafer W. Accordingly, a state of the plasma generated when a voltage is applied to the lower electrode103B can be made more uniform in a plane of the wafer W. Accordingly, a uniform plasma processing result in the plane of the wafer W can be obtained.

Even when the wafer support101shown inFIG.3or the like is used, or the wafer support101A inFIG.19is used, a recess similar to the recess EB1of the edge ring EB may be provided on the lower surface of the edge ring.

Further, as in a wafer support101C inFIG.21, a groove104Cd recessed downward may be formed to have an annular shape in plan view on an upper surface104Cb of a peripheral portion of an electrostatic chuck104C. The gas discharge hole104cmay be formed in the groove104Cd. Specifically, one end of the gas discharge hole104cmay be open in the groove104Cd.

Even when the wafer support101A inFIG.19or the wafer support101B inFIG.20is used, a groove similar to the groove104Cd may be provided on the upper surface of the peripheral portion of the electrostatic chuck.

It shall be understood that the embodiments disclosed herein are illustrative and are not restrictive in all aspects. The embodiment described above may be omitted, replaced, or modified in various forms without departing from the scope and spirit of the appended claims. For example, the components of the embodiments described above may be combined as desired. From the desired combination, functions and effects of each component related to the combination can be obtained as a matter of course, and other functions and effects apparent to those skilled in the art can be obtained from the description herein.

The effects described herein are merely illustrative or exemplary, and are not limited. In other words, the technique according to the present disclosure may have other effects apparent to those skilled in the art from the description herein, in addition to or in place of the effects described above.

The following configuration examples also fall within the technical scope of the present disclosure.

(1) A substrate processing system including a plasma processing apparatus, a pressure-reduced transfer device connected to the plasma processing apparatus, and a controller, in which the plasma processing apparatus has a processing container configured to be pressure-reduced, a substrate support that is provided in the processing container and that includes a substrate placing surface, a ring placing surface on which an edge ring is placed to surround the substrate placing surface, and an electrostatic chuck that electrostatically attracts the edge ring to the ring placing surface, an elevation mechanism that elevates the edge ring with respect to the ring placing surface, a supply path for supplying a gas to a space between a rear surface of the edge ring and the ring placing surface, and a pressure sensor connected to the supply path, the pressure-reduced transfer device has a transfer robot that transfers the edge ring, and the controller controls lowering the edge ring that is transferred into the processing container by the transfer robot and that is transferred to the elevation mechanism, via the elevation mechanism and placing the edge ring on the ring placing surface, electrostatically attracting the placed edge ring to the ring placing surface, supplying the gas to the supply path to maintain a pressure in the supply path to be higher than a pressure in the processing container after the electrostatic attracting, measuring the pressure in the supply path, and determining a placing state of the edge ring on the ring placing surface based on the measured pressure.

(2) The substrate processing system according to (1), in which the electrostatic chuck includes a first electrode and a second electrode formed at positions different from each other, and any one of voltages having polarities different from each other or voltages having the same polarity are configured to be applied to the first electrode and the second electrode.

(3) The substrate processing system according to (1) or (2), in which the plasma processing apparatus further has a gas supply that discharges another gas into the processing container, and in the placing, the edge ring is placed on the ring placing surface while the other gas is discharged into the processing container.

(4) The substrate processing system according to any one of (1) to (3), in which the plasma processing apparatus further has a plasma generator that generates a plasma in the processing container, and in the electrostatic attracting, the edge ring is electrostatically attracted in a state where the plasma is generated in the processing container.

(5) The substrate processing system according to any one of (1) to (4), in which in the measuring of the pressure, the pressure in the supply path after a predetermined time elapses from stopping of the supply of the gas in the supplying of the gas is measured, and in the determining, the placing state of the edge ring on the ring placing surface is determined based on whether the pressure in the supply path measured in the measuring of the pressure is less than a threshold value.

(6) The substrate processing system according to any one of (1) to (5), in which the transfer robot has a holder configured to hold a substrate to be transferred, and a measurement unit that is provided in the holder and that measures information related to a misalignment amount of the edge ring with respect to the electrostatic chuck, and when a determination that the placing state of the edge ring on the ring placing surface is not appropriate is made, the controller further controls performing measurement via the measurement unit, and calculating the misalignment amount of the edge ring based on a measurement result of the measurement unit.

(7) The substrate processing system according to (6), in which when the calculated misalignment amount exceeds a threshold value, the controller further controls adjusting a position of the edge ring on the ring placing surface.

(8) The substrate processing system according to (7), in which the adjusting includes releasing the electrostatic attracting of the edge ring, raising the edge ring via the elevation mechanism, and then transferring the edge ring to the transfer robot, then moving the edge ring to a position based on the calculated misalignment amount, and then returning the edge ring to the elevation mechanism and then lowering the edge ring via the elevation mechanism and placing the edge ring on the ring placing surface again.

(9) The substrate processing system according to any one of (1) to (8), in which the transfer robot has the holder configured to hold the edge ring to be transferred, and the measurement unit that is provided in the holder and that measures the information related to the misalignment amount of the edge ring with respect to the electrostatic chuck, and when a determination that the placing state of the edge ring on the ring placing surface is appropriate is made, the controller further controls performing measurement via the measurement unit, and calculating the misalignment amount of the edge ring based on the measurement result of the measurement unit.

(10) The substrate processing system according to (9), in which when the calculated misalignment amount exceeds the threshold value, the controller further controls adjusting a position of the edge ring on the ring placing surface.

(11) The substrate processing system according to (9) or (10), in which when the calculated misalignment amount is less than or equal to the threshold value, the controller further controls performing processing of stabilizing the electrostatic attracting of the edge ring.

(12) The substrate processing system according to any one of (1) to (8), in which when a determination that the placing state of the edge ring on the ring placing surface is appropriate is made, the controller further controls performing processing of stabilizing the electrostatic attracting of the edge ring.

(13) The substrate processing system according to any one of (1) to (12), in which the gas is a heat transfer gas.

(14) The substrate processing system according to any one of (1) to (13), in which the plasma processing apparatus further has an exhaust path for exhausting air between the rear surface of the edge ring and the ring placing surface, and the controller further controls vacuum- attracting the edge ring to the ring placing surface before electrostatically attracting the edge ring placed on the ring placing surface to the ring placing surface.

(15) A substrate processing system including a plasma processing apparatus, a pressure-reduced transfer device connected to the plasma processing apparatus, and a controller, in which the plasma processing apparatus has a processing container configured to be pressure-reduced, a substrate support that is provided in the processing container and that includes a substrate placing surface, a ring placing surface on which an edge ring is placed to surround the substrate placing surface, and an electrostatic chuck that electrostatically attracts the edge ring to the ring placing surface, an elevation mechanism that elevates the edge ring with respect to the ring placing surface, and a supply path for supplying a gas to a space between a rear surface of the edge ring and the ring placing surface, the pressure-reduced transfer device has a transfer robot that transfers the edge ring, the transfer robot has a holder configured to hold the edge ring to be transferred, and a measurement unit that is provided in the holder and that measures information related to a misalignment amount of the edge ring with respect to the electrostatic chuck, and the controller controls lowering the edge ring that is transferred into the processing container by the transfer robot and that is transferred to the elevation mechanism, via the elevation mechanism and placing the edge ring on the ring placing surface, electrostatically attracting the placed edge ring to the ring placing surface, performing measurement via the measurement unit after the electrostatic attracting, and calculating the misalignment amount of the edge ring based on a measurement result of the measurement unit.

(16) The substrate processing system according to (15), in which the controller further controls, before the electrostatic attracting, performing measurement via the measurement unit, and calculating the misalignment amount of the edge ring based on the measurement result of the measurement unit.

(17) The substrate processing system according to (15) or (16), in which the electrostatic chuck has a first electrode and a second electrode formed at positions different from each other, and voltages having polarities different from each other and voltages having the same polarity are configured to be supplied to the first electrode and the second electrode.

(18) The substrate processing system according to any one of (15) to (17), in which the plasma processing apparatus further has a gas supply that discharges another gas into the processing container, and in the placing, the edge ring is placed on the ring placing surface while the other gas is discharged into the processing container.

(19) The substrate processing system according to any one of (15) to (18), in which the plasma processing apparatus further has a plasma generator that generates a plasma in the processing container, and in the electrostatic attracting, the edge ring is electrostatically attracted in a state where the plasma is generated in the processing container.

(20) The substrate processing system according to any one of (15) to (19), in which when the calculated misalignment amount exceeds a threshold value, the controller further controls adjusting a position of the edge ring on the ring placing surface.

(21) The substrate processing system according to any one of (15) to (20), in which when the calculated misalignment amount is less than or equal to the threshold value, the controller further controls performing processing of stabilizing the electrostatic attracting of the edge ring.

(22) The substrate processing system according to any one of (15) to (21), in which the plasma processing apparatus further has an exhaust path for exhausting air between the rear surface of the edge ring and the ring placing surface, and the controller further controls vacuum-attracting the edge ring to the ring placing surface before electrostatically attracting the edge ring placed on the ring placing surface to the ring placing surface.

The present invention encompasses various modifications to each of the examples and embodiments discussed herein. According to the invention, one or more features described above in one embodiment or example can be equally applied to another embodiment or example described above. The features of one or more embodiments or examples described above can be combined into each of the embodiments or examples described above. Any full or partial combination of one or more embodiment or examples of the invention is also part of the invention.