SUBSTRATE SUPPORT AND PLASMA PROCESSING APPARATUS

There is provided a substrate support that achieves both tilt controllability and uniformity of plasma density in a circumferential direction of a substrate. The substrate support includes: a substrate support surface for supporting the substrate; a ring support surface for supporting an edge ring; and an electrostatic chuck. The electrostatic chuck includes a first bias electrode and a second bias electrode, the first bias electrode is provided at least partially below the substrate support surface, the second bias electrode is provided at least partially below the ring support surface, and the first bias electrode and the second bias electrode overlap each other in a plan view in at least a partial region outside the substrate support surface and below the ring support surface.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Japanese Patent Application No. 2023-104740,filed on Jun. 27, 2023, the entire contents of which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a substrate support and a plasma processing apparatus.

BACKGROUND

JP2021-158134A discloses a substrate support including a first region where a substrate is to be placed, and a second region where an edge ring is to be placed. The substrate support includes a first electrode provided in the first region for receiving a first electric bias, and a second electrode provided in the second region for receiving a second electric bias, and the second electrode extends below the first electrode to face the first electrode in the first region.

CITATION LIST

Patent Documents

SUMMARY

A technique according to the present disclosure provides a substrate support that achieves both tilt controllability and uniformity of plasma density in a circumferential direction of a substrate.

According to an aspect of the present disclosure, there is provided a substrate support including: a substrate support surface configured to support a substrate; a ring support surface configured to support an edge ring; and an electrostatic chuck. The electrostatic chuck includes a first bias electrode and a second bias electrode, the first bias electrode is provided at least partially below the substrate support surface, the second bias electrode is provided at least partially below the ring support surface, and the first bias electrode and the second bias electrode overlap each other in a plan view in at least a partial region outside the substrate support surface and below the ring support surface.

According to the present disclosure, it is possible to provide the substrate support that achieves both tilt controllability and uniformity of plasma density in a circumferential direction of the substrate.

DETAILED DESCRIPTION

In a process of manufacturing a semiconductor device, various processing steps are performed in which a processing module that accommodates a semiconductor substrate (hereinafter, referred to as a “substrate”) is brought into a pressure-reduced state, and the substrate is subjected to processing including plasma processing. The plurality of processing steps are performed using, for example, a substrate processing apparatus in which a plurality of processing modules are disposed around a common transport module.

In the processing module, the substrate is placed on a substrate support. In addition to the substrate, an edge ring is placed on the substrate support to surround a periphery of the substrate. A bias signal corresponding to a purpose of the plasma processing is supplied to the substrate or the edge ring placed on the substrate support.

JP2021-158134A discloses a substrate support including a first electrode provided in a first region where a substrate is to be placed, and a second electrode provided in a second region where an edge ring is to be placed, and the second electrode extends below the first electrode to face the first electrode in the first region. The first electrode and the second electrode are electrodes to which bias potentials are applied, and face each other within and at a lower side of the first region. It is described that by such a configuration in which the first electrode and the second electrode face each other within the first region, the first electrode and the second electrode are capacitively coupled, and a potential difference between the substrate and the edge ring is reduced. It is described that by reducing the potential difference, it is possible to appropriately control a tilt related to a plasma incident angle at a substrate peripheral edge portion.

However, when the present inventor intensively studied the configuration in which the first electrode and the second electrode face each other within the first region, that is, within the substrate, the following was found. That is, according to the configuration in which a part of the first electrode and a part of the second electrode face each other, when bias power is supplied to the electrodes during plasma generation, a boundary of plasma density may be formed between a first electrode side and a second electrode side above the part where the electrodes face each other. The boundary of plasma density is formed above the first electrode, that is, above the substrate. The boundary of plasma density formed above the substrate is susceptible to electromagnetic components of an electrostatic chuck (such as terminals connected to a chuck electrode and a bias electrode). Therefore, uniformity of the plasma density in a circumferential direction easily deteriorates above the substrate. The uniformity in the circumferential direction is improved when adopting a configuration in which a region of the part where the electrodes face each other is reduced, but in this case, there is a trade-off relationship that the above tilt controllability decreases.

Therefore, a technique according to the present disclosure provides a substrate support capable of preventing deterioration in uniformity in a circumferential direction above a substrate while maintaining tilt controllability of a substrate peripheral edge portion.

Hereinafter, a configuration of a substrate processing apparatus according to the present embodiment will be described with reference to the drawings. The same reference numerals will be given to elements having substantially the same functional configurations throughout the specification, and redundant description thereof will be omitted.

Plasma Processing System

FIG.1is a diagram for explaining an example of a configuration of a plasma processing system. In an embodiment, a plasma processing system includes a plasma processing apparatus1and a controller2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus1is an example of a substrate processing apparatus. The plasma processing apparatus1includes a plasma processing chamber10, a substrate support11, and a plasma generator12. The plasma processing chamber10has a plasma processing space. Further, the plasma processing chamber10has at least one gas supply port for supplying at least one processing gas into the plasma processing space, and at least one gas exhaust port for exhausting the gas from the plasma processing space. The gas supply port is connected to a gas supply20which will be described later, and the gas exhaust port is connected to an exhaust system40which will be described later. The substrate support11is disposed in the plasma processing space and has a substrate support surface150afor supporting a substrate W, which will be described later.

The plasma generator12is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. Further, various types of plasma generators, including an alternating current (AC) plasma generator and a direct current (DC) plasma generator, may be used. In one embodiment, an AC signal (AC power) used by the AC plasma generator has a frequency in a range of 100 kHz to 10 GHz. Accordingly, the AC signal includes a radio frequency (RF) signal and a microwave signal. In one embodiment, the RF signal has a frequency in a range of 100 kHz to 150 MHz.

The controller2processes computer-executable instructions for instructing the plasma processing apparatus1to execute various steps described herein below. The controller2may be configured to control the respective components of the plasma processing apparatus1to execute the various steps described herein below. In an embodiment, part or all of the controller2may be included in the plasma processing apparatus1. The controller2may include a processor2a1, a storage unit2a2, and a communication interface2a3. The controller2is implemented by, for example, a computer2a.The processor2a1may be configured to read a program from the storage unit2a2and perform various control operations by executing the read program. The program may be stored in advance in the storage unit2a2, or may be acquired via a medium when necessary. The acquired program is stored in the storage unit2a2, and is read from the storage unit2a2and executed by the processor2a1. The medium may be various storing media readable by the computer2a,or may be a communication line connected to the communication interface2a3. The processor2a1may be a Central Processing Unit (CPU). The storage unit2a2may 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 interface2a3may communicate with the plasma processing apparatus1via a communication line such as a local area network (LAN).

Plasma Processing Apparatus

Hereinafter, a configuration example of a capacitively-coupled plasma processing apparatus1as an example of the plasma processing apparatus1will be described.FIG.2is a view for explaining an example of a configuration of the capacitively-coupled plasma processing apparatus1.

The plasma processing apparatus1according to the present embodiment includes the plasma processing chamber10, the gas supply20, a power source30, and the exhaust system40. Further, the plasma processing apparatus1includes the substrate support11and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber10. The gas introduction unit includes a shower head13. The substrate support11is disposed in the plasma processing chamber10. The shower head13is disposed above the substrate support11. In one embodiment, the shower head13constitutes at least a part of a ceiling of the plasma processing chamber10. The plasma processing chamber10has a plasma processing space10sdefined by the shower head13, a sidewall10aof the plasma processing chamber10, and the substrate support11. The plasma processing chamber10is grounded. The shower head13and the substrate support11are electrically insulated from a housing of the plasma processing chamber10.

The shower head13is configured to introduce at least one processing gas from the gas supply20into the plasma processing space10s.The shower head13has at least one gas supply port13a,at least one gas diffusion chamber13b,and a plurality of gas introduction ports13c. The processing gas supplied to the gas supply port13apasses through the gas diffusion chamber13band is introduced into the plasma processing space10sfrom the plurality of gas introduction ports13c.Further, the shower head13includes at least one upper electrode. The gas introduction unit may include, in addition to the shower head13, one or a plurality of side gas injectors (SGI) that are attached to one or a plurality of openings formed in the sidewall10a.

The gas supply20may include at least one gas source21and at least one flow rate controller22. In one embodiment, the gas supply20is configured to supply at least one processing gas from the respective corresponding gas sources21to the shower head13via the respective corresponding flow rate controllers22. Each flow rate controller22may include, for example, a mass flow controller or a pressure-controlled flow rate controller. Further, the gas supply20may include at least one flow rate modulation device that modulates or pulses the flow rate of at least one processing gas.

The power source30includes an RF power source31coupled to the plasma processing chamber10via at least one impedance matching circuit. The RF power source31is configured to supply at least one RF signal (RF power) to at least one lower electrode and/or at least one upper electrode. As a result, plasma is formed from at least one processing gas supplied into the plasma processing space10s.Accordingly, the RF power source31may function as at least a part of the plasma generator12.

In one embodiment, a bias RF signal is supplied to two or more bias lower electrodes130to be described later, so that a bias potential is generated in the substrate W and an edge ring113, ion components in the formed plasma are drawn into the substrate W, and a tilt in a substrate peripheral edge portion can be controlled. For convenience of description, the bias lower electrode130and other lower electrodes will be described separately in the specification. However, the bias lower electrode130may have a function as another lower electrode, and when simply referred to as a “lower electrode”, the bias lower electrode130is also included. The two or more bias lower electrodes130include a first bias electrode and a second bias electrode (to be described later), to which the same or different bias RF signals are supplied.

In one embodiment, the RF power source31includes a first RF generator31aand a second RF generator31b.The first RF generator31ais configured to be coupled to at least one lower electrode and/or at least one upper electrode via at least one impedance matching circuit to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generator31amay be configured to generate a plurality of source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and/or at least one upper electrode.

Further, the second RF generator31bis configured to be coupled to two or more bias lower electrodes130via at least one impedance matching circuit to generate a bias RF signal (bias RF power). A frequency of the bias RF signal may be the same as or different from a frequency of the source RF signal. In one embodiment, the bias RF signal has a lower frequency than the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generator31bmay be configured to generate a plurality of bias RF signals having different frequencies. In this case, the plurality of generated bias RF signals are supplied to at least the first bias electrode or the second bias electrode (to be described later), or to both. Further, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

In one embodiment, the power source30includes a DC power source32coupled to the plasma processing chamber10. The DC power source32includes a first DC generator32aand a second DC generator32b.In one embodiment, the first DC generator32ais configured to be connected to at least one lower electrode to generate a first DC signal. The generated first DC signal is applied to at least one lower electrode. In one embodiment, the second DC generator32bis configured to be connected to at least one upper electrode to generate a second DC signal. The generated second DC signal is applied to at least one upper electrode.

In one embodiment, the first DC generator32asupplies a bias DC signal serving as the first DC signal to the two or more bias lower electrodes130to be described later, so that a bias potential is generated in the substrate W and the edge ring113, ion components in the formed plasma are drawn into the substrate W, and a tilt in a substrate peripheral edge portion can be controlled. In this case, the same or different bias DC signals are supplied to a first bias electrode130aand a second bias electrode130bto be described later.

In various embodiments, the first and second DC signals may be pulsed. In this case, the sequence of voltage pulses is applied to at least one lower electrode and/or at least one upper electrode. The voltage pulse may have a pulse waveform of a rectangle, a trapezoid, a triangle or a combination thereof. In one embodiment, a waveform generator for generating a sequence of voltage pulses from the DC signal is connected between the first DC generator32aand at least one lower electrode. Accordingly, the first DC generator32aand the waveform generator configure a voltage pulse generator. In a case where the second DC generator32band the waveform generator configure the voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulse may have a positive polarity or a negative polarity. Further, the sequence of the voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses in one cycle. The first and second DC generators32aand32bmay be provided in addition to the RF power source31, and the first DC generator32amay be provided instead of the second RF generator31b.

The exhaust system40may be connected to, for example, a gas exhaust port10edisposed at a bottom portion of the plasma processing chamber10. The exhaust system40may include a pressure adjusting valve and a vacuum pump. The pressure in the plasma processing space10sis adjusted by the pressure adjusting valve. The vacuum pump may include a turbo molecular pump, a dry pump, or a combination thereof.

Substrate Support

First Embodiment

The substrate support11according to a first embodiment includes a main body111and a ring assembly112. The main body111includes a central region111athat is a central region for supporting the substrate W, and an annular region111bthat is an annular region for supporting the ring assembly112. The annular region111bof the main body111surrounds the central region111aof the main body111in a plan view. The substrate W is disposed on the central region111aof the main body111and the ring assembly112is disposed on the annular region111bof the main body111to surround the substrate W on the central region111aof the main body111. The ring assembly112includes one or more annular members. In one embodiment, one or more annular members include one or more edge rings113and at least one cover ring. The edge ring113is formed of a conductive material or an insulating material, and the cover ring is formed of an insulating material.

The main body111includes a base120and an electrostatic chuck121. The base120includes a conductive member. The conductive member of the base120may function as a lower electrode. The electrostatic chuck121is disposed on the base120. The electrostatic chuck121includes a ceramic member122. The ceramic member122includes the central region111aand the annular region111b.The electrostatic chuck121includes the bias lower electrode130and a chuck electrode140in the ceramic member122. The bias lower electrode130includes the first bias electrode130aprovided below the substrate support surface150ato be described later, and the second bias electrode130bprovided below a ring support surface150bto be described later. The chuck electrode140includes a first chuck electrode140aprovided below the central region111aand a second chuck electrode140bprovided below the annular region111b.Other members that surround the electrostatic chuck121, such as an annular electrostatic chuck and an annular insulating member, may have the annular region111b.In this case, the ring assembly112may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck121and the annular insulating member.

In one embodiment, at least one other RF/DC electrode coupled to the RF power source31and/or the DC power source32described above may be disposed in the ceramic member122. In this case, the other RF/DC electrodes function as lower electrodes. Further, in this case, the conductive member of the base120and at least one other RF/DC electrode may function as a plurality of lower electrodes.

Further, the substrate support11may include a temperature control module configured to adjust at least one of the electrostatic chuck121, the ring assembly112, and the substrate W to a target temperature. The temperature control module may include a heater, a heat transfer medium, a flow path120a,or a combination thereof. A heat transfer fluid, such as brine or gas, flows through the flow path120a.In one embodiment, the flow path120ais formed in the base120, and one or more heaters are disposed in the ceramic member122of the electrostatic chuck121. Further, the substrate support11may include a heat transfer gas supply configured to supply a heat transfer gas to a gap between a back surface of the substrate W and the central region111a.

Bias Lower Electrode

FIGS.3and4are a cross-sectional view and a plan view as viewed from above, respectively, schematically illustrating a configuration example of the bias lower electrode130according to the first embodiment.FIG.3illustrates an example of a state of the substrate support11on which the substrate W and the edge ring113are placed, and components of the ring assembly112other than the edge ring are not illustrated for convenience of description. InFIG.4, the substrate W and the edge ring113are not illustrated for convenience of description.

As shown inFIG.3, the substrate W is placed on the substrate support surface150a, and the edge ring113is placed on the ring support surface150b.The substrate support surface150ais a surface including a region that overlaps the substrate W in the plan view when the substrate W is placed thereon. Further, the ring support surface150bis a surface including a region that overlaps the edge ring113in the plan view when the edge ring113is placed thereon. In this configuration example, the substrate support surface150acoincides with the central region111aof the ceramic member122, and the ring support surface150bcoincides with the annular region111bof the ceramic member122.

As shown inFIG.4, the first bias electrode130a,which is indicated by a portion surrounded by a dotted circle, has a substantially disk shape. Further, the second bias electrode130b,which is indicated by a portion surrounded by two circles of dash-dotted lines, has a substantially annular shape. The first bias electrode130aextends below the entire surface of the substrate support surface150aand extends to a partial region outside the substrate support surface150aand below the ring support surface150b.Further, the second bias electrode130bextends below the ring support surface150b.With this configuration, the first bias electrode130aand the second bias electrode130boverlap each other in the plan view in a region outside the substrate support surface150aand below the ring support surface150b.The region is referred to as a crosstalk region CTR, and an overlapped configuration in the plan view in the crosstalk region CTR is referred to as “crosstalk outside the substrate”. Outside the substrate support surface150ameans outside a circle defining an outer periphery of the substrate support surface150ain the plan view as shown inFIG.4. In the example shown inFIG.4, the circle defining the outer periphery of the substrate support surface150aoverlaps the circle indicated by the dash-dotted line inside the second bias electrode130b,and thus outside the substrate support surface150ameans outside the circle indicated by the dash-dotted line inside the second bias electrode130b.

Further, the substrate support11is provided with a first bias power supply160athat supplies bias power to the first bias electrode130a,and a second bias power supply160bthat supplies bias power to the second bias electrode130b.The first bias power supply160aincludes a first connection layer161aprovided parallel to the first bias electrode130ainside the ceramic member122, and a plurality of first connectors162athat connect the first connection layer161ato the first bias electrode130aat multiple points. Similarly, the second bias power supply160bincludes a second connection layer161bprovided parallel to the second bias electrode130binside the ceramic member122, and a plurality of second connectors162bthat connect the second connection layer161bto the second bias electrode130bat multiple points. A first bias power source165ais connected to the first connection layer161avia a first supply terminal163aand a circuit164a.Further, a second bias power source165bis connected to the second connection layer161bvia a second supply terminal163band a circuit164b.In one embodiment, the first supply terminal163aand the second supply terminal163bare provided inside the base120and the ceramic member122outside the substrate support surface150a.

In one embodiment, the first bias power source165a,the second bias power source165b,and the circuits164aand164bare included in the power source30. In this case, the first bias power source165a,the second bias power source165b,and the circuits164aand164bmay be included in the second RF generator31b,and the circuits164aand164bmay include impedance matching circuits.

Further, a first adsorption power supply170athat supplies adsorption power to the first chuck electrode140aand a second adsorption power supply170bthat supplies adsorption power to the second chuck electrode140bare provided inside the base120and the ceramic member122. The first adsorption power supply170aincludes a vertical connector171provided inside the ceramic member122and connected perpendicularly to the first chuck electrode140a. In this configuration example, the vertical connector171is provided at a position overlapping a central axis AX of the main body111.

According to the substrate support11in the configuration example described above, the crosstalk region CTR is located outside the substrate support surface150a.Therefore, by controlling bias signals supplied to the first bias electrode130aand the second bias electrode130b,it is possible to control a tilt in a substrate peripheral edge portion during plasma generation above the crosstalk region CTR.

Further, when the bias signal is supplied to the bias lower electrode130during the plasma generation, a boundary of plasma density may be formed between a substrate upper side and an edge ring upper side above the crosstalk region CTR. In the crosstalk outside the substrate according to the present embodiment, a boundary of plasma density is formed above the second bias electrode130b,that is, above the edge ring113. As a result, uniformity of plasma density in a circumferential direction above the substrate can be improved.

Further, by connecting the first bias power supply160ato the second bias power supply160bat multiple points by the plurality of first connectors162aand the plurality of second connectors162bvia the first connection layer161aand the second connection layer161b,and by providing the first supply terminal163aand the second supply terminal163boutside the substrate support surface150a,electromagnetic influence of the terminals on the boundary of plasma density generated above the crosstalk region CTR can be minimized, and the uniformity of plasma density in the circumferential direction above the substrate and above the edge ring113can be further improved.

Further, by providing the vertical connector171at the position overlapping the central axis AX of the main body111in the first adsorption power supply170a,the electromagnetic influence of the terminal on the uniformity of plasma density in the circumferential direction can be minimized.

Hereinafter, various embodiments of the substrate support11will be described with reference toFIGS.5to12. The various embodiments shown inFIGS.3to12are not mutually exclusive, and may be combined as desired, as long as the embodiments exhibit the above-described functions and effects regarding maintaining tilt controllability and improving the uniformity of plasma density in the circumferential direction.

Second Embodiment

The substrate support11according to a second embodiment shown inFIG.5is different from the substrate support11according to the first embodiment in configurations of the edge ring113and the substrate support surface150a.A recess180is formed in an upper surface of the edge ring113according to the second embodiment. The substrate support surface150ais a region combining the central region111aof the ceramic member122with the recess180. With this configuration, the substrate support surface150aand the ring support surface150bpartially overlap each other in a plan view. In this case, the crosstalk region CTR is outside the substrate support surface150a.In the substrate support11according to the second embodiment, by configuring the crosstalk region CTR as described above, the same functions and effects as those in the first embodiment can be obtained.

Third Embodiment

The substrate support11according to a third embodiment shown inFIG.6is different from the substrate support11according to the first embodiment in configurations of the first bias power supply160a,the second bias power supply160b,the first adsorption power supply170a,and the second adsorption power supply170b.Each of the first bias power supply160aand the second bias power supply160baccording to the third embodiment does not include a connection layer and a plurality of connectors, and is connected to the bias electrode by one connection terminal. The first bias power supply160ais located at a position overlapping the central axis AX of the main body111. Further, the first adsorption power supply170aand the second adsorption power supply170bare located so that a vertical portion181provided inside the base120and indicated by a thick line inFIG.6is symmetrical with respect to the central axis AX. The second adsorption power supply170bis provided with a horizontal portion indicated by a dotted line inFIG.6at the same height as the second bias electrode130b.Further, the second bias power supply160band a connection terminal of the second adsorption power supply170b,which is connected perpendicularly to the second chuck electrode140bbeyond the horizontal portion, are coaxially located. In the substrate support11according to the third embodiment, the connection layer, the plurality of connectors and the likes are not provided in the first bias power supply160aand the second bias power supply160b,and the terminals are arranged symmetrically in a circumferential direction. According to this arrangement, it is possible to minimize deterioration in uniformity in the circumferential direction due to electromagnetic influence of the terminal on a boundary of plasma density that may be formed above the crosstalk region CTR.

In the following fourth to sixth embodiments, configurations of the first bias power supply160a,the second bias power supply160b,the first adsorption power supply170a,and the second adsorption power supply170bare the same as those in the third embodiment for convenience of description, although not limited thereto.

Fourth Embodiment

The substrate support11according to a fourth embodiment shown inFIG.7is different from the substrate support11according to the third embodiment in a configuration of the second bias electrode130b.The second bias electrode130baccording to the fourth embodiment extends not only below the ring support surface150bbut also below the substrate support surface150a.With this configuration, the crosstalk region CTR is located below across both the substrate support surface150aand the ring support surface150b.In the substrate support11according to the fourth embodiment, by configuring the crosstalk region CTR as described above, a boundary of plasma density that may be formed above the crosstalk region CTR is also formed above the substrate W. Even in this case, uniformity in a circumferential direction can be improved through the same operations and effects as in the third embodiment, compared to a case where at least the entire crosstalk region CTR is located inside the substrate support surface150a.

Fifth Embodiment

The substrate support11according to a fifth embodiment shown inFIG.8is different from the substrate support11according to the third embodiment in configurations of the first bias electrode130aand the second bias electrode130b.The first bias electrode130aaccording to the fifth embodiment extends not only below the substrate support surface150abut also below the entire surface of the ring support surface150b.Further, the second bias electrode130bextends not only below the ring support surface150bbut also below the substrate support surface150a.The second bias electrode130bdoes not extend below the entire surface of the ring support surface150b,but extends below only a partial region. In the substrate support11according to the fifth embodiment, by providing the first bias power supply160aextending below the entire surfaces of both the substrate support surface150aand the ring support surface150b,uniformity of plasma density in a circumferential direction above both the substrate support surface150aand the ring support surface150bcan be improved. Further, tilt controllability on the substrate peripheral edge portion can be maintained by the crosstalk region CTR where the first bias power supply160aoverlaps the second bias electrode130bextending below at least a part of the ring support surface150bin a plan view.

Sixth Embodiment

The substrate support11according to a sixth embodiment shown inFIG.9is different from the substrate support11according to the third embodiment in configurations of the first bias electrode130aand the second bias electrode130b.The first bias electrode130aaccording to the sixth embodiment is the same as that according to the fifth embodiment. The second bias electrode130bextends below only a part of the ring support surface150b.In the substrate support11according to the sixth embodiment, in addition to obtaining the same operations and effects as those of the substrate support11according to the fifth embodiment, since there is no crosstalk region inside the substrate support surface150a,no boundary of plasma density is formed above the substrate support surface150a,and uniformity in a circumferential direction above the substrate can be improved.

Seventh Embodiment

The substrate support11according to a seventh embodiment shown inFIG.10is different from the substrate support11according to the third embodiment in a configuration of the first bias power supply160a.The first bias power supply160aaccording to the seventh embodiment is located outside the substrate support surface150aand is symmetrical with the second bias power supply160bacross the central axis AX. In the substrate support11according to the seventh embodiment, a connection layer, a plurality of connectors, and the likes are not provided in the first bias power supply160aand the second bias power supply160b,and the terminals are arranged symmetrically in a circumferential direction. According to this arrangement, it is possible to minimize deterioration in uniformity in the circumferential direction due to electromagnetic influence of the terminal on a boundary of plasma density that may be formed above the crosstalk region CTR.

Eighth Embodiment

The substrate support11according to an eighth embodiment shown inFIG.11is different from the substrate support11according to the third embodiment in a configuration of the ceramic member122of the electrostatic chuck121. The ceramic member122according to the eighth embodiment includes a first layer190a,a second layer190b,and a third layer190cin this order from an upper side toward a lower side. A first ceramic material forming the first layer190aand the third layer190cand a second ceramic material forming the second layer190bare different materials. The first layer190aconstitutes the substrate support surface150aand the ring support surface150b,and includes the second bias electrode130b.Further, the third layer190cincludes the first bias electrode130a.In other words, the ceramic member122has a configuration in which the first layer190aincluding the second bias electrode130band the third layer190cincluding the first bias electrode130aare separated by the second layer190b.In the substrate support11according to the eighth embodiment, a desired configuration can be obtained by, for example, adjusting a distance between the first bias electrode130aand the second bias electrode130b,adjusting a thickness of the second layer190b,or selecting the second ceramic material. Specifically, a capacitance ratio of a capacitance between the base120and the substrate W to a capacitance between the base120and the edge ring113can be a desired value. Further, a capacitance ratio of a capacitance between the first bias electrode130aand the substrate W to a capacitance between the second bias electrode130band the edge ring113can be a desired value. As an example, the capacitance ratios are both 1:1.

Ninth Embodiment

The substrate support11according to a ninth embodiment shown inFIG.12is different from the substrate support11according to the third embodiment in configurations of the first bias electrode130aand the second bias electrode130b.Inside the ceramic member122according to the ninth embodiment, the first bias electrode130ais provided above the second bias electrode130b.With this configuration, the crosstalk region CTR can also be provided outside the substrate. In the substrate support11according to the ninth embodiment, by configuring the crosstalk region CTR as described above, the same functions and effects as those in the third embodiment can be obtained.

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 support includes:a substrate support surface configured to support a substrate;a ring support surface configured to support an edge ring; andan electrostatic chuck.The electrostatic chuck includes a first bias electrode and a second bias electrode, the first bias electrode is provided at least partially below the substrate support surface, the second bias electrode is provided at least partially below the ring support surface, andthe first bias electrode and the second bias electrode overlap each other in a plan view in at least a partial region outside the substrate support surface and below the ring support surface.(2) In the substrate support according to (1),the first bias electrode extends below an entire surface of the substrate support surface and extends to at least a partial region outside the substrate support surface and below the ring support surface.(3) In the substrate support according to (1) or (2),the first bias electrode is provided below the second bias electrode.(4) The substrate support according to any one of (1) to (3) further includes:a first bias power supply configured to supply first bias power to the first bias electrode.

A connection point between the first bias electrode and the first bias power supply is provided outside the substrate support surface in the plan view.

(5) The substrate support according to any one of (1) to (3) further includes:a first bias power supply configured to supply first bias power to the first bias electrode; anda second bias power supply configured to supply second bias power to the second bias electrode.

The first bias power supply includesa first connection layer provided parallel to the first bias electrode, anda plurality of first connectors provided between the first connection layer and the first bias electrode, andthe second bias power supply includesa second connection layer provided parallel to the second bias electrode, anda plurality of second connectors provided between the second connection layer and the second bias electrode.(6) In the substrate support according to any one of (1) to (5),the electrostatic chuck includesa chuck electrode provided below the substrate support surface, andan adsorption power supply configured to supply adsorption power to the chuck electrode,the adsorption power supply includes a vertical portion extending perpendicularly to the substrate support surface and connected to the chuck electrode, andthe vertical portion overlaps a central axis of the substrate support in the plan view.(7) The substrate support according to any one of (1) to (6) further includes:a base provided below the electrostatic chuck.

A capacitance ratio of a capacitance between the base and the substrate to a capacitance between the base and the edge ring is 1:1, anda capacitance ratio of a capacitance between the first bias electrode and the substrate to a capacitance between the second bias electrode and the edge ring is 1:1.(8) In the substrate support according to any one of (1) to (7),the electrostatic chuck includes a first layer, a second layer, and a third layer in this order from an upper side toward a lower side,a first dielectric material forming the first layer and the third layer and a second dielectric material forming the second layer are different materials,the first layer constitutes the substrate support surface and the ring support surface, and includes the second bias electrode, andthe third layer includes the first bias electrode.(9) A plasma processing apparatus includes:a substrate support including a substrate support surface configured to support a substrate, a ring support surface configured to support an edge ring, and an electrostatic chuck.

The electrostatic chuck includes a first bias electrode and a second bias electrode,the first bias electrode is provided at least partially below the substrate support surface,the second bias electrode is provided at least partially below the ring support surface, andthe first bias electrode and the second bias electrode overlap each other in a plan view in at least a partial region outside the substrate support surface and below the ring support surface.(10) The plasma processing apparatus according to (9) further includes:a first bias power source configured to supply first bias power to the first bias electrode; anda second bias power source configured to supply second bias power to the second bias electrode.(11) In the plasma processing apparatus according to (8) or (9),the first bias power source and the second bias power source are DC power sources, andthe first bias power and the second bias power are DC power.