Substrate treatment device and tray

Abstract

Provided is a substrate treatment device that appropriately performs sheath control with respect to a substrate outer peripheral section and appropriately performs control of a consumption amount with respect to an annular part of a tray. The substrate treatment device for treating a substrate includes: a treatment chamber; and a support member disposed in the treatment chamber and including, on an upper surface, a tray support surface for supporting the tray. The tray includes a base part and a peripheral edge part forming a recess part that accommodates the substrate on an upper surface of the base part. The base part and the peripheral edge part are configured as separate bodies.

Description

Substrate processing apparatus and tray

[0001] The present disclosure relates to substrate processing apparatus and trays for holding substrates.

[0002] Patent Document 1 discloses a substrate processing system for processing substrates, in which a wafer to be processed and an edge ring arranged to surround the wafer are electrostatically attracted to a disk-shaped tray and transported to a process module in this state. Patent Document 1 also discloses that the substrate processing system places the wafer and edge ring on a susceptor in a process module via the tray and performs plasma processing such as etching in this state.

[0003] Japanese Patent Application Publication No. 2021-34390

[0004] The technology according to the present disclosure appropriately controls the sheath around the outer periphery of a substrate in a substrate processing apparatus, and also appropriately controls the amount of wear on the annular portion of a tray.

[0005] One aspect of the present disclosure is a substrate processing apparatus for processing substrates, comprising: a processing chamber; and a support member disposed within the processing chamber and having a tray support surface on an upper surface thereof for supporting a tray, wherein the tray includes a base portion and a peripheral portion that forms a recess on the upper surface of the base portion for accommodating the substrate, and the base portion and the peripheral portion are configured as separate entities.

[0006] In a substrate processing apparatus, the sheath around the outer periphery of a substrate is appropriately controlled, and the amount of wear of the annular portion of a tray is appropriately controlled.

[0007] 1 is a plan view schematically showing an example of the configuration of a wafer processing system; FIG. 2 is a cross-sectional view schematically showing an example of the configuration of a wafer processing module; FIG. 3 is a diagram illustrating the flow of wafer processing in the wafer processing system; FIG. 4 is a cross-sectional view schematically showing an example of the configuration of a tray according to the present embodiment; FIG. 5 is a cross-sectional view schematically showing a spacer provided on a tray; FIG. 6 is a cross-sectional view schematically showing another method of loading wafers onto a tray; FIG. 7 is a cross-sectional view schematically showing another example of the configuration of a tray; FIG. 8 is a cross-sectional view schematically showing another example of the configuration of a tray; FIG. 9 is a cross-sectional view schematically showing another example of the configuration of a tray; FIG. 10 is a cross-sectional view schematically showing an example of the configuration of a tray; FIG. 11 is a cross-sectional view schematically showing an example of the structure near a circular ring portion; FIG. 12 is a cross-sectional view schematically showing an example of the structure near a circular ring portion; FIG. 13 is a cross-sectional view schematically showing an example of the structure near a circular ring portion; FIG. 14 is a cross-sectional view schematically showing an example of the structure near a circular ring portion; FIG. 1 is an explanatory diagram showing an example of a method for separating a wafer from a tray. FIG. 2 is an explanatory diagram showing an example of a method for separating a wafer from a tray. FIG. 3 is a cross-sectional view schematically showing another configuration example of a tray. FIG. 4 is a cross-sectional view schematically showing another configuration example of a tray. FIG. 5 is a cross-sectional view schematically showing another configuration example of a tray. FIG. 6 is an explanatory diagram showing an example of a tray transport method. FIG. 7 is a cross-sectional view schematically showing an example of a method for fixing a tray to a support member. FIG. 8 is a cross-sectional view schematically showing an example of a method for fixing a tray to a support member. FIG. 9 is a perspective view showing an example of a configuration of a locking mechanism that fixes a tray to a support member. FIG. 10 is a cross-sectional view schematically showing an example of a method for fixing a tray to a support member. FIG. 11 is a cross-sectional view schematically showing an example of a method for fixing a tray to a support member. FIG. 12 is a cross-sectional view schematically showing an example of a method for detaching a tray from a support member.

[0008] In the manufacturing process of semiconductor devices, various plasma processes such as etching, film formation, diffusion, etc. are performed on semiconductor substrates (hereinafter sometimes referred to as "wafers") In these plasma processes, in order to obtain uniform processing results across the wafer, it is important to ensure uniformity in temperature and electric field throughout the wafer during processing, including the periphery of the wafer.

[0009] In a substrate processing system, when a wafer to be processed and an edge ring are held by suction on a disk-shaped tray and then transported to a process module and subjected to plasma processing in this state, it is necessary to improve the temperature uniformity and electric field uniformity, including, for example, the outer periphery of the wafer W that does not directly contact the susceptor. Furthermore, when the wafer processing is an etching process as a plasma processing, it is desirable to control tilting at the outermost periphery of the wafer W.

[0010] The disk-shaped tray includes a central portion (disk portion, described later) that holds the wafer and an outer peripheral portion (annular portion, described later). When the outer peripheral portion is used as an edge ring during plasma processing, it functions similarly to a conventional edge ring. In other words, in order to control the product quality of the wafer's outer peripheral portion, it is important to understand the wear rate of the annular portion and to control the sheath at the wafer edge.

[0011] The technology disclosed herein has been developed in consideration of the above circumstances, and provides a substrate processing apparatus that appropriately controls the sheath around the outer periphery of a substrate and appropriately controls the wear rate of a circular ring. A wafer processing system including a wafer processing module according to this embodiment will be described below with reference to the drawings. Note that in this specification and the drawings, elements having substantially the same functional configuration are designated by the same reference numerals, and redundant description will be omitted.

[0012] <Configuration of Wafer Processing System> FIG. 1 is a plan view schematically illustrating the configuration of a wafer processing system 1. In the wafer processing system 1, various processes are performed on a wafer W serving as a substrate. The wafer W is an example of a substrate. The wafer W is, for example, a semiconductor wafer such as a semiconductor substrate, and in one embodiment, a device layer (not shown) including multiple devices is formed on the surface. In the wafer processing system 1 according to this embodiment, the wafer W to be processed is transported and processed while placed on a tray T (described later) (see FIG. 2). The wafer W is loaded on the tray T with the surface on which the device layer is formed facing upward. For ease of explanation, the tray T holding the wafer W to be transported and processed in the wafer processing system 1 may be referred to as a "tray Tw." The detailed configuration of the tray T will be described later.

[0013] In the following embodiments, an example will be described in which a device layer is formed on the surface of the wafer W as described above, but the wafer W does not necessarily have to be a device wafer on which a device layer is formed.

[0014] 1, the wafer processing system 1 has a configuration in which an atmospheric transfer module 2 and a vacuum transfer module 3 are integrally connected via a load lock module 4. The atmospheric transfer module 2 transfers trays Tw in an atmospheric atmosphere, while the vacuum transfer module 3 transfers trays Tw in a vacuum (reduced pressure) atmosphere.

[0015] The load lock module 4 has one or more load lock chambers 4a, for example, two in this embodiment. The load lock chamber 4a is provided so as to communicate with the internal space of the atmospheric transfer module 2 and the internal space of the vacuum transfer module 3 via a transfer port. The transfer port is configured to be freely opened and closed by a gate valve 4b.

[0016] The load lock module 4 is configured to temporarily hold the tray Tw. The load lock module 4 is also configured so that the interior can be switched between atmospheric and reduced pressure (vacuum state). That is, the load lock module 4 is configured so that the tray Tw can be appropriately transferred between the atmospheric transfer module 2, which is in the atmospheric pressure, and the vacuum transfer module 3, which is in the reduced pressure.

[0017] The atmospheric transfer module 2 comprises a rectangular housing, and the interior of the housing is maintained at atmospheric pressure. A plurality of load ports 5, for example, three load ports 5, are connected in a line to one side of the atmospheric transfer module 2, which constitutes the long side on the negative Y-axis direction side. The two load lock chambers 4a described above are connected in a line to the other side of the atmospheric transfer module 2, which constitutes the long side on the positive Y-axis direction side. The atmospheric transfer module 2 may further be connected to an orienter module (not shown) that adjusts the horizontal orientation of the trays Tw, a storage module (not shown) that stores multiple trays Tw, and the like.

[0018] A FOUP F capable of storing multiple trays Tw is placed on the load port 5. Above the wafer processing system 1, an overhead transport mechanism (OHT: not shown) is provided that is movable along rails arranged on the ceiling surface of the clean room in which the wafer processing system 1 is placed. The FOUP F accesses the wafer processing system 1 via this overhead transport mechanism and is delivered to the load port 5.

[0019] A first transfer mechanism 6 for transferring trays Tw is provided inside the atmospheric transfer module 2. The first transfer mechanism 6 is configured to be able to transfer trays Tw between the FOUP F of the load port 5 and the load lock chamber 4a of the load lock module 4. The configuration of the first transfer mechanism 6 is not particularly limited.

[0020] The vacuum transfer module 3 is made of a flat rectangular housing, the interior of which can be maintained in a vacuum (reduced pressure) atmosphere. A plurality of, for example, four wafer processing modules 7 are connected to the side of the vacuum transfer module 3. The internal space of the wafer processing module 7 communicates with the internal space of the vacuum transfer module 3 via a transfer port. The transfer port is configured to be freely opened and closed by a gate valve 7a. The number and arrangement of the wafer processing modules 7 are not limited to those in this embodiment and can be set as desired.

[0021] A second transfer mechanism 8 for transferring trays Tw is provided inside the vacuum transfer module 3. The second transfer mechanism 8 is configured to be able to transfer trays Tw between the load lock chamber 4a of the load lock module 4 and one or more wafer processing modules 7. The configuration of the second transfer mechanism 8 is not particularly limited.

[0022] In one example, the wafer processing module 7 serving as a substrate processing apparatus performs plasma processing such as etching on wafers W placed on trays T. Fig. 2 is a diagram illustrating an example in which the wafer processing module 7 is a capacitively coupled plasma processing apparatus.

[0023] The wafer processing module 7, which is a capacitively coupled plasma processing apparatus, includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The wafer processing module 7 also includes a support member 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 15. The support member 11 is disposed within the plasma processing chamber 10. The showerhead 15 is disposed above the support member 11. In one embodiment, the showerhead 15 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 15, a sidewall 10a of the plasma processing chamber 10, and the support member 11. The plasma processing chamber 10 is grounded. The showerhead 15 and the support member 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0024] The support member 11 includes a base 12, an electrostatic chuck 13, and a lifter 14. The base 12 includes a conductive member. The conductive member of the base 12 can function as a lower electrode. The electrostatic chuck 13 is disposed on the base 12. The electrostatic chuck 13 includes a ceramic member 13a and an electrostatic electrode 13b disposed within the ceramic member 13a. The ceramic member 13a is made of a dielectric material and has a tray support surface for supporting a tray Tw, and the electrostatic chuck 13 including this ceramic member 13a is configured as a tray support portion. In one embodiment, the tray support surface of the ceramic member 13a has a diameter larger than that of a wafer W placed on the tray T and a diameter smaller than or approximately the same size as that of the tray T.

[0025] Furthermore, at least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32, which will be described later, may be disposed within the ceramic member 13a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal, which will be described later, is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 12 and the at least one RF / DC electrode may function as multiple lower electrodes. Alternatively, the electrostatic electrode 13b may function as a lower electrode. Therefore, the support member 11 includes at least one lower electrode.

[0026] The lifter 14 has a plurality of lift pins 14a (three in this embodiment) and an actuator 14b which is a drive mechanism for vertically moving the lift pins 14a. A plurality of through holes 12h (three in this embodiment) are formed in each of the base 12 and the electrostatic chuck 13, penetrating them in the thickness direction, and the lift pins 14a of the lifter 14 are inserted into the through holes 12h (13h). Examples of the actuator 14b include an electric actuator, an air cylinder, a motor, etc.

[0027] The lifter 14 moves the lift pins 14a along the axial direction (vertical direction) using the actuators 14b, thereby raising and lowering the tray Tw on the electrostatic chuck 13. In this way, the tray Tw is moved between a transfer height at which the tray Tw is transferred to and from the second transport mechanism 8 and a processing height at which wafer processing is performed on the electrostatic chuck 13.

[0028] The support member 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 13, the tray T, and the wafer W to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path 12a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow path 12a. In one embodiment, the flow path 12a is formed in the base 12, and one or more heaters are disposed in the ceramic member 13a of the electrostatic chuck 13. The support member 11 may also include a gas (e.g., nitrogen (N ２ The gas supply may include a gas supply configured to supply a gas (a) or gas (b) to the gas supply 20 described below.

[0029] The showerhead 15 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 15 has at least one gas supply port 15a, at least one gas diffusion chamber 15b, and multiple gas inlets 15c. The process gas supplied to the gas supply port 15a passes through the gas diffusion chamber 15b and is introduced into the plasma processing space 10s from the multiple gas inlets 15c. The showerhead 15 also includes at least one upper electrode. In addition to the showerhead 15, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0030] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 15 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0031] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates a plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the wafer W, thereby attracting ion components in the formed plasma to the wafer W.

[0032] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple 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.

[0033] The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0034] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to the at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0035] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one period. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0036] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0037] Although the wafer processing module 7 is configured as described above in one example, the configuration of the wafer processing module 7 is not limited to this.

[0038] 2, the case where the plasma generating unit of the wafer processing module 7 generates capacitively coupled plasma (CCP) has been described as an example. However, the plasma generated by the plasma generating unit may be inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. Various types of plasma generators may be used, including alternating current (AC) plasma generators and direct current (DC) plasma generators. In one embodiment, the AC signal (AC power) used in the AC plasma generator has a frequency in the range of 100 kHz to 10 GHz. Thus, AC signals include radio frequency (RF) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0039] Returning to the description of FIG. 1 , the wafer processing system 1 described above is provided with a control unit 9 as shown in FIG. 1 . The control unit 9 processes computer-executable instructions that cause the wafer processing system 1 to perform the various steps described in this disclosure. The control unit 9 may be configured to control each element of the wafer processing system 1 to perform the various steps described herein. In one embodiment, part or all of the control unit 9 may be included in the wafer processing system 1. The control unit 9 may include a processing unit 9a1, a storage unit 9a2, and a communication interface 9a3. The control unit 9 is realized by, for example, a computer 9a. The processing unit 9a1 may be configured to read a program from the storage unit 9a2 and execute the read program to perform various control operations. This program may be stored in the storage unit 9a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 9a2 and is read from the storage unit 9a2 by the processing unit 9a1 and executed. The medium may be various storage media readable by the computer 9a, or may be a communication line connected to the communication interface 9a3. The processing unit 9a1 may be a CPU (Central Processing Unit). The storage unit 9a2 may include a RAM (Random Access Memory), a ROM (Read Only Memory), a HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface 9a3 may communicate with the wafer processing system 1 via a communication line such as a LAN (Local Area Network). The storage medium may be temporary or non-temporary.

[0040] <Processing Flow in Wafer Processing System> Next, wafer processing performed using the wafer processing system 1 configured as described above will be described along with the flow of tray Tw transport. Figure 3 is a diagram for explaining the main steps of wafer processing. As mentioned above, the following description will be given taking as an example a case where the wafer W is a device wafer having a device layer formed on its front surface side, but the wafer W does not necessarily have to have a device layer formed thereon.

[0041] First, prior to transporting the FOUP F to the wafer processing system 1, a wafer W to be processed is loaded onto a tray T by a loading device (not shown) provided outside the wafer processing system 1, and the tray Tw loaded with the wafer W is prepared (step S1 in FIG. 3). At this time, the wafer W is loaded onto the tray T with the surface on which the device layer is formed facing upward. The tray Tw loaded with the wafer W is accommodated in the FOUP F (step S2 in FIG. 3). The tray Tw is accommodated in the FOUP F with the wafer support surface on which the wafer W is loaded facing upward.

[0042] Next, the FOUP F containing multiple trays Tw is transported by an overhead transport mechanism (OHT) (not shown) and loaded onto the load port 5 of the wafer processing system 1 (step S3 in FIG. 3 ). Next, the trays Tw are removed from the FOUP F by the first transport mechanism 6 and transported to one wafer processing module 7 via the load lock chamber 4a of the load lock module 4 and the second transport mechanism 8. In the wafer processing module 7, the back side of the tray Tw carrying the wafers W (the side opposite to the wafer support surface on which the wafers W are placed) is attracted and held by the electrostatic chuck 13 of the support member 11 (step S4 in FIG. 3 ). Note that, as will be described later, electrostatic attraction by the electrostatic chuck 13 is not necessarily required if, for example, the weight of the tray Tw can sufficiently bring the wafers W into contact with the support member 11 and sufficiently cool the wafers W.

[0043] In the wafer processing module 7, any process depending on the purpose of wafer processing, for example, plasma processing such as etching, is performed (step S5 in FIG. 3 ). Specifically, for example, after loading a wafer W, the interior of the plasma processing chamber 10 is depressurized to a desired vacuum level, and then a desired processing gas is supplied to the plasma processing space 10s. Then, the RF power source 31 supplies at least one RF signal (RF power) to at least one lower electrode and / or at least one upper electrode, exciting the processing gas and generating plasma. The plasma processing is then performed on the wafer W by the action of the plasma thus generated. At this time, the plasma processing is performed on the wafer W while the wafer W is placed on a tray T.

[0044] After the desired wafer processing has been performed on the wafers W, the tray Tw is then transferred out of the wafer processing module 7 by the second transfer mechanism 8. The tray Tw transferred out of the wafer processing module 7 is returned to the FOUP F via the load lock chamber 4a of the load lock module 4 and the first transfer mechanism 6 (step S6 in FIG. 3).

[0045] The FOUP F containing the processed wafers W is then carried out of the wafer processing system 1 by an overhead transport mechanism (OHT) (not shown) (step S7 in FIG. 3). Thereafter, the tray T and the wafers W are separated by a separation device (not shown) provided outside the wafer processing system 1 (step S8 in FIG. 3). In this way, a series of wafer processing steps using the wafer processing system 1 is completed.

[0046] According to this embodiment, as described above, with the wafer W to be processed placed on the tray T, the wafer is transported in the wafer processing system 1 and then processed in the wafer processing module 7 in that order.

[0047] 3 , the case where wafers W are loaded onto trays T in advance outside the wafer processing system 1, in other words, the case where trays Tw are carried into the wafer processing system 1, has been described as an example. However, loading of wafers W onto trays T does not necessarily have to be performed outside the wafer processing system 1, but may be performed inside the wafer processing system 1. In this case, a FOUP F accommodating a plurality of trays T and a FOUP F accommodating a plurality of wafers W are respectively carried into the wafer processing system 1, and the wafers W are loaded onto / separated from the trays T in a loading device (not shown) / separation device (not shown) connected to the atmospheric transfer module 2, for example. In this case, the loading device and the separation device may be independently disposed, and the loading and separation of wafers W onto / from the trays T may be performed in different devices, or the loading device and the separation device may be configured as an integrated unit, and the loading and separation of wafers W onto / from the trays T may be performed in the same device.

[0048] <Detailed Structure of Tray> Next, a detailed structure of the tray T on which the wafer W is mounted will be described. Fig. 4 is a cross-sectional view showing a schematic example of the configuration of the tray T, illustrating a state in which the tray T is disposed above the support member 11 of the wafer processing module 7. Note that, for simplification of the illustration, the through holes 12h and 13h are omitted in Fig. 4.

[0049] 4 , the tray T has a substantially disk shape and a concave cross-sectional shape in which the thickness of the central portion is smaller than the thickness of the peripheral portion in a cross-sectional view. Hereinafter, for convenience, the central portion of the tray T, which is thinner in a cross-sectional view, will be referred to as the "disk portion 101," and the peripheral portion of the tray T, which is thicker in a cross-sectional view, will be referred to as the "annular portion 102." The concave cross-sectional shape formed by the disk portion 101 and the annular portion 102 may also be referred to as the "recess 103." The tray T also has a first heat transfer material 104 disposed between the wafer W and the upper surface of the disk portion 101 when the tray T accommodates the wafer W, and a second heat transfer material 105 disposed between the tray mounting surface of the electrostatic chuck 13 and the lower surface of the disk portion 101 when the tray T is placed on the tray mounting surface.

[0050] The disk portion 101 is made of, for example, Si, SiC, SiN, C, or SiO ２ , Al ２ O３ , Y ２ O ３ , YOF, W, Ti, TiN, ZeO ２ , and green sheets. Therefore, the disk portion 101 may be made of a conductive material or an insulating material. The relative dielectric constant of the disk portion 101 may be 8.0 or less. The volume resistivity of the disk portion 101 may be 1×10e12 [Ω cm] or less when the electrostatic chuck 13 is a JR (Johnson-Rahbek) type, or 1×10e13 [Ω cm] or more when the electrostatic chuck 13 is a Coulomb type.

[0051] The diameter r1 of the circular plate portion 101 is slightly larger than the diameter r3 of the wafer W so that the wafer W can be accommodated therein. Therefore, the circular plate portion 101 of the tray T has a wafer mounting surface for supporting the wafer W, and the tray T has a recess 103 for accommodating the wafer W. When the wafer W is placed on the wafer mounting surface, a gap G (the difference between the diameter r1 and the diameter r3) between the outer edge of the wafer W and the inner peripheral surface of the annular portion 102 is preferably 0.1 mm or less. Furthermore, in order to efficiently cool the wafer W (described later), the diameter r1 of the circular plate portion 101 is preferably equal to or smaller than the diameter r4 of the support member 11 (electrostatic chuck 13) that holds the tray Tw in the wafer processing module 7. The thickness t1 of the circular plate portion 101 is not particularly limited, but is preferably set to a thickness that allows for efficient cooling of the wafer W (described later) and ensures the mechanical strength of the tray T.

[0052] The annular portion 102 is made of, for example, Si, SiC, SiN, C, or SiO ２ , Al ２ O ３ , Y ２ O ３ , YOF, W, Ti, TiN, ZeO ２, and green sheets, and may be made of the same material as the disk portion 101 or a different material. Therefore, the annular portion 102 may be made of a conductive material or an insulating material. However, when the annular portion 102 is used as an edge ring in plasma processing as described below, it may be made of the same material as a conventional edge ring. Furthermore, it is desirable that the relative permittivity and volume resistivity of the annular portion 102 are the same as those of the wafer W.

[0053] The thickness t2 of the annular portion 102 can be changed as appropriate depending on the purpose of wafer processing. Therefore, the height of the upper surface of the annular portion 102 may be greater than, smaller than, or the same as the height of the upper surface of the wafer W. The thickness t2 of the annular portion 102 is, for example, 3 mm to 5 mm. During plasma processing in the wafer processing module 7, the annular portion 102 is disposed so as to surround the periphery of the wafer W held on the disk portion 101, and also functions as an edge ring (also called a focus ring) to reduce non-uniformity in the plasma processing. Therefore, the thickness t2 and width r2 of the annular portion 102 may be configured to be approximately the same as the thickness and width of an edge ring (not shown) used in conventional plasma processing.

[0054] The diameter of the entire tray T (i.e., the outer diameter of the annular portion 102, which is the diameter r1+width r2) may be equal to or larger than the diameter r4 of the support member 11 (electrostatic chuck 13) that holds the tray Tw in the wafer processing module 7 (diameter r1+width r2≧diameter r4). In this case, by making the tray T larger than the support member 11, it is possible to prevent the surface of the support member 11 (electrostatic chuck 13) from being exposed to plasma during plasma processing in the wafer processing module 7. This reduces wear on the support member 11 and reduces the time and frequency required for maintenance of the wafer processing module 7.

[0055] Furthermore, as described above, a gap G is formed between the outer edge of the wafer W and the inner peripheral surface of the annular portion 102. In the area where this gap G is formed, the corners of the recess 103 may be exposed to plasma during plasma processing in the wafer processing module 7. In this case, depending on the material of the tray T, wear may easily occur at the corners, which may shorten the life of the tray T or cause particle generation. It has been found that this wear at the corners is more likely to occur when the corners have a right-angle shape.

[0056] Therefore, in order to suppress wear at the corners of the recess 103, the corners may not be shaped like right angles, but may be filled with the space between the wafer W and the tray T. Specifically, as shown in FIG. 5, for example, it is desirable to provide rounded spacers 106 at the corners 103a of the recess 103. Although not shown, instead of rounded spacers, spacers configured to match the shape of the outer edge of the wafer W may be provided. In this case, the spacers 106 are made of a material that is at least plasma-resistant. By providing the spacers 106 at the corners 103a in this manner, exposure of the corners 103a to plasma during plasma processing in the wafer processing module 7 is suppressed, thereby suppressing a decrease in the lifespan of the tray T and the generation of particles.

[0057] In addition, the spacer 106 to be placed in the corner portion 103a may be configured as a separate body from the tray T (disk portion 101 and annular portion 102) as shown in Figure 5, and may be configured as an integral part with at least one of the disk portion 101 or the annular portion 102, although this is not shown in the figure.

[0058] 4 and 5, the wafer W is held on the circular plate portion 101 of the tray T. However, as shown in FIG. 6, a step 107 for holding the outer periphery of the wafer W may be provided on the annular portion 102, and the wafer W may be held on the step 107. Alternatively, instead of the step 107, the wafer W may be held on the spacer 106 shown in FIG. 5. In other words, the spacer 106 may have a rectangular cross section and may be formed with the step 107 for holding the outer periphery of the wafer W. In this case, a gap is generated between the back surface of the wafer W and the circular plate portion 101 of the tray T. However, by filling this gap with a first heat transfer material 104, which will be described later, the wafer W can be appropriately cooled, as will be described later.

[0059] FIG. 4 illustrates an example in which the disc portion 101 and the annular portion 102 of the tray T are integrally formed using the same material, but the configuration of the tray T is not limited thereto. In one embodiment, as shown in FIG. 7 , the tray T may be configured such that the diameter r1 of the disc portion 101 and the outer diameter of the annular portion 102 are the same, and the annular portion 102 is disposed on the upper surface of the disc portion 101. In this case, the disc portion 101 is configured as a base portion for mounting a wafer W at its center, and a mounting surface (ring mounting surface) for the annular portion 102 serving as an edge ring is provided on the upper surface. In this case, the annular portion 102 serving as a peripheral portion is mounted on the upper surface of the disc portion 101 serving as a base portion, and a recess 103 for accommodating the wafer W is formed. That is, the disc portion 101 serving as a base portion and the annular portion 102 serving as a peripheral portion may be configured as separate bodies. In this case, the disc portion 101 and the annular portion 102 may be made of different materials. Furthermore, in this case, a conventional edge ring may be used as the annular portion 102 .

[0060] 4 and 7, the disk portion 101 and the annular portion 102 are each made of a single member, but at least one of the disk portion 101 and the annular portion 102 may be made of two or more laminated members as shown in Fig. 8. In this case, the laminated members may be made of different materials as shown in Fig. 8, or may be made of the same material, although this is not shown.

[0061] 4, 7, and 8 illustrate an example in which the recess 103 is formed on the upper surface (wafer mounting surface) of the tray T, but instead of or in addition to this, a recess 108 may be further formed on the lower surface of the tray T as shown in Figures 9 and 10. In this case, it is desirable that the recess 108 formed on the lower surface of the tray T has a shape that fits into the tray support surface of the electrostatic chuck 13, as shown in Figure 10.

[0062] 4, the first heat transfer material 104 is disposed between the wafer W and the wafer mounting surface of the tray T. Therefore, the first heat transfer material 104 is disposed in the recess 103 of the tray T. As will be described later, a liquid heat transfer material or a heat transfer sheet can be used as the first heat transfer material 104. The wafer W placed on the tray T comes into thermal contact with the tray T over the entire surface via the first heat transfer material 104, thereby improving the cooling efficiency of the wafer W by the heat transfer fluid flowing through the flow path 12a formed in the base 12.

[0063] More specifically, in conventional plasma processing apparatuses, the wafer support surface of the electrostatic chuck is typically made smaller than the wafer to be held (the wafer diameter is greater than the outer diameter of the electrostatic chuck) to prevent the surface of the electrostatic chuck from being worn away by exposure to plasma. However, in this case, the outer periphery of the wafer is not directly held by the electrostatic chuck, which can result in insufficient cooling of the outer periphery compared to the center of the wafer. Furthermore, if the wafer W is deformed due to warping, for example, this can make it difficult to achieve uniform solid contact between the electrostatic chuck and the entire surface of the wafer. As a result, the pressing force against the electrostatic chuck is weakened in a portion of the wafer surface (the portion that is warped upward), which can result in insufficient cooling of that portion of the wafer surface.

[0064] In this regard, as in the technology according to this embodiment, by storing the wafer W inside the recess 103 of the tray T and further providing a first heat transfer material 104 between the wafer W and the disk portion 101 of the tray T, the wafer W and the tray T can be easily brought into full contact with each other via the first heat transfer material 104, and the entire surface of the wafer W can be uniformly cooled.

[0065] As the first heat transfer material 104, for example, a liquid heat transfer material or a sheet heat transfer material can be selected, but a gas may also be used as the first heat transfer material 104 as long as the wafer W and the tray T are appropriately brought into full contact with each other and the heat transfer efficiency between the wafer W and the tray T can be improved.

[0066] 4, the second heat transfer material 105 is disposed between the tray T and the tray mounting surface of the electrostatic chuck 13. As the second heat transfer material 105, a liquid heat transfer material or a heat transfer sheet can be used, as described below. The second heat transfer material 105 may be the same material as the first heat transfer material 104, or a different material. The tray T held by the electrostatic chuck 13 is in thermal contact with the electrostatic chuck 13 over the entire surface via the second heat transfer material 105. This improves the cooling efficiency of the tray T, and therefore the cooling efficiency of the wafer W mounted on the tray T, by the heat transfer fluid flowing through the flow path 12a formed in the base 12.

[0067] More specifically, in conventional plasma processing apparatuses, in order to sufficiently cool the wafer on the electrostatic chuck, it was necessary to increase the pressing force of the wafer against the wafer mounting surface of the electrostatic chuck, for example, by electrostatic force, and to appropriately maintain solid contact between the electrostatic chuck and the wafer.

[0068] In this regard, as in the technology according to the present embodiment, by providing the second heat transfer material 105 between the tray T and the tray support surface of the electrostatic chuck 13, the tray T and the electrostatic chuck 13 can be easily brought into thermal contact via the second heat transfer material 105, and a sufficient cooling effect for the wafer W can be expected due to the weight of the tray Tw without applying stress such as electrostatic adsorption. Note that although the wafer W can be cooled by the weight of the tray Tw by providing the second heat transfer material 105 in this manner, it is also possible to hold the tray T on the electrostatic chuck 13 by electrostatic adsorption or the like. In this case, the pressing force of the tray T against the electrostatic chuck 13 is increased, and the cooling efficiency for the wafer W can be further improved.

[0069] The tray T according to this embodiment is configured as described above as an example. According to this embodiment, the annular portion 102, which functions as a conventional edge ring, is transported together with the wafer W. In other words, after a single wafer is processed in the wafer processing module 7, the edge ring (annular portion 102) and the wafer W are transported together from the wafer processing module 7. As a result, even if the edge ring (annular portion 102) is worn out by plasma processing, it is not necessary to stop operation of the wafer processing module 7 for edge ring replacement, as in the conventional method. Instead, the annular portion 102 transported from the wafer processing module 7 after a single wafer is processed can be replaced directly outside the wafer processing module 7. This maximizes the operating time of the wafer processing module 7.

[0070] Furthermore, since the edge ring (annular portion 102) is replaced for each wafer processed in this manner, wear on the edge ring due to continuous wafer processing in the wafer processing module 7 is suppressed, and as a result, the impact of edge ring wear on the process results is suppressed.

[0071] Note that the trays T worn by the plasma processing in this way may be regenerated by adding on only the worn portion after being carried out from the wafer processing module 7, and then the wafers W may be loaded again and transported to the wafer processing module 7. For example, the worn portion may be regenerated by adding on by thermal spraying, or by using CVD, PVD, sol-gel, or additive manufacturing technology (3D printing technology). Alternatively, the trays T may be subjected to rough sorting and surface blasting to separate them into constituent materials, and then reused as new processed products separate from the trays T. Furthermore, the Si powder obtained by sorting may be used to regenerate the worn portion of the trays T described above after powder production.

[0072] <Example of structure near annular portion> For example, when wafer processing in wafer processing module 7 is an etching process as plasma processing, it is desirable to control tilting at the outermost periphery of wafer W. If the annular portion 102 of tray T is worn away by plasma processing and the height of the upper surface of the annular portion 102 changes, the position of the plasma sheath formed above the outer periphery of wafer W will be lower than the position of the plasma sheath formed above the center of wafer W, which will tilt the angle of ion incidence with respect to wafer W and tilt the etching groove formed at the outermost periphery of wafer W (tilting).

[0073] Due to the above-mentioned circumstances, in order to appropriately control tilting at the outermost periphery of the wafer W, it is necessary to effectively drive the annular portion 102 and set the height of its upper surface to a desired height. Therefore, in one embodiment, as shown in Fig. 7, the disk portion 101 serving as the base and the annular portion 102 serving as the peripheral portion may be configured as separate bodies, and only the annular portion 102 serving as the peripheral portion may be configured to be raised and lowered. Specifically, as shown in Fig. 11, lift pins 202 may be provided that are inserted into through-holes 200 formed to penetrate the base 12, the electrostatic chuck 13, and the disk portion 101 serving as the base.

[0074] The lift pin 202 may be composed of a tip portion 202a that can be inserted into a through hole 200a formed in the disk portion 101 serving as a base portion, and a root portion 202b that can be inserted into through holes 200b formed in the base 12 and the electrostatic chuck 13. In one embodiment, the diameter A1 of the tip portion 202a may be smaller than the diameter A2 of the root portion 202b. Correspondingly, the diameter of the through hole 200a may be smaller than the diameter of the through hole 200b. That is, a step portion 203 is formed in the through hole 200 at the boundary between the through holes 200a and 200b, and as the root portion 202b rises and falls, the root portion 202b comes into contact with the step portion 203, thereby raising and lowering the disk portion 101 serving as a base portion. In one embodiment, the tip portion 202a and the base portion 202b can be raised and lowered independently. By raising and lowering the tip portion 202a, only the annular portion 102 as the peripheral portion can be raised and lowered as shown in FIG. 12, and by raising and lowering the base portion 202b, both the annular portion 102 as the peripheral portion and the disk portion 101 as the base portion can be raised and lowered as shown in FIG. 13.

[0075] 12 , only the annular portion 102 serving as the peripheral portion is raised and lowered when, for example, tilting at the outermost periphery of the wafer W is controlled when performing an etching process as a plasma process on the wafer W. Specifically, if the upper surface height of the annular portion 102 is lower than the upper surface height at the center of the wafer W, the position of the plasma sheath formed above the outer periphery of the wafer W is lowered, and the ion incidence angle is tilted radially inward of the wafer W. In this case, by raising only the annular portion 102, the upper surface height of the annular portion 102 can be adjusted to match the upper surface height at the center of the wafer W, thereby correcting the position of the plasma sheath. Furthermore, by raising the upper surface height of the annular portion 102 higher than the upper surface height at the center of the wafer W, the position of the plasma sheath formed above the outer periphery of the wafer W can be raised, and the ion incidence angle can be intentionally tilted radially outward of the wafer W depending on the etching process. 13, both the annular portion 102 as the peripheral portion and the disk portion 101 as the base portion are raised and lowered when, for example, the second transfer mechanism 8 is inserted onto the back side of a tray Tw loaded with wafers W to transfer the tray Tw. That is, by raising both the annular portion 102 as the peripheral portion and the disk portion 101 as the base portion, the second transfer mechanism 8 can be inserted onto the back side of the tray Tw, and the tray Tw can be easily transferred.

[0076] The method for controlling the lift pins 202 is not limited, but may be a control operation by the control unit 9, for example.

[0077] Furthermore, it is necessary to grasp the amount of wear of the annular portion 102 in order to appropriately control tilting at the outermost periphery of the wafer W and control the product quality of the outer periphery of the wafer W. Therefore, in one embodiment, the amount of wear of the annular portion 102 may be measured by irradiating light onto the annular portion 102 as the peripheral portion and measuring the thickness of the annular portion 102.

[0078] For example, as shown in FIG. 14 , a transmission path 210 may be provided so as to penetrate the base 12, the electrostatic chuck 13, and the disk portion 101 serving as the base, and light L may be irradiated from a light source 212 onto the annular portion 102 serving as the peripheral portion. The transmission path 210 may be provided by partially using different materials for the base 12, the electrostatic chuck 13, and the disk portion 101 serving as the base, as shown in FIG. 14 . The material constituting the transmission path 210 is not limited as long as it transmits light L of the wavelength irradiated from the light source 212, and may be, for example, sapphire, quartz, or the like. The number and arrangement of the transmission paths 210 are arbitrary, and the transmission paths 210 may be provided at one location or at multiple locations in the circumferential direction.

[0079] Furthermore, when providing the transmission path 210, part or all of the base 12, the electrostatic chuck 13, and the disk portion 101 serving as the base may be made of a material that transmits the light L of the wavelength irradiated from the light source 212. For example, as shown in Fig. 15, the electrostatic chuck 13 and the disk portion 101 serving as the base may be made of a material that transmits the light L, and the transmission path 210 may be provided only in the base 12. The material that transmits the light L may be any material, and may be, for example, sapphire, quartz, or the like.

[0080] The light source 212 is not particularly limited, but may be, for example, an optical sensor that receives and detects light reflected from the upper surface of the annular portion 102 as the peripheral portion and light reflected from the lower surface, and measures the thickness of the annular portion 102 based on the phase difference between these reflected lights. The wavelength of the light used as the light L may be 1.5 μm to 2.7 μm, and in that case, the material that constitutes the transmission path 210 may be Si or SiO ２ may be.

[0081] Furthermore, a DC signal may be applied to the annular portion 102 serving as the peripheral portion in order to appropriately control tilting at the outermost periphery of the wafer W. In one embodiment, as shown in Figures 16 and 17, lift pins 202 that lift and lower only the annular portion 102 serving as the peripheral portion may be formed of a conductive material, and these lift pins 202 may be electrically connected to the DC power supply 32. In other words, a configuration may be adopted in which DC power is supplied from the DC power supply 32 to the annular portion 102 serving as the peripheral portion via the lift pins 202.

[0082] As described above, the base 12 includes a conductive material, and the conductive material of the base 12 can function as a lower electrode. That is, an RF signal may be applied to the base 12. In this case, it is preferable to provide an insulating material between the base 12 and the lift pins 202. For example, although not shown, if the lift pins 202 are made of a conductive material, an insulating sleeve may be provided around the lift pins 202. Furthermore, although not shown, the lift pins 202 may be electrically connected to an RF power supply 31 instead of the DC power supply 32. In this case, an RF signal is applied to the annular portion 102 serving as the peripheral portion.

[0083] <Method of Loading / Separating Wafer from Tray> Next, an example of a method of loading a wafer W onto a tray T in the loading device (not shown) and a method of separating a wafer W from the tray T in the separating device (not shown) will be described.

[0084] (1) Use of Lift Pins When loading / unloading a wafer W onto / from a tray T, through-holes 101h formed in the disk portion 101 can be used. That is, as shown in FIG. 18 , in the loading / unloading device, with the tray T placed on a stage, lift pins are configured to freely protrude and retract from the upper surface of the disk portion 101 through the through-holes 101h formed in the disk portion 101 of the tray T. This allows the lower surface of the wafer W loaded onto the tray T to be supported by the lift pins and moved (lifted up) in the vertical direction, thereby realizing loading / unloading of the wafer W onto / from the tray T. Note that the wafer W is transported between the loading / unloading device and the outside of the loading / unloading device by, for example, being held by a transfer mechanism provided outside the loading / unloading device. At this time, the transfer mechanism holds the back side of the wafer W opposite to the front side on which the device layer is formed or the outer edge of the wafer W in order to prevent damage to the device layer formed on the front side of the wafer W. For example, when the transfer mechanism holds the backside of the wafer W, as shown in FIG. 18, the wafer W is configured to be inserted between the wafer W and the stage in a state where the wafer W is lifted up by the lift pins.

[0085] (2) Use of Fluid When separating the wafer W from the tray T, instead of or in addition to the lift pins and insertion members In described above, a fluid may be introduced between the wafer W and the tray T, i.e., into the recess 103.

[0086] Specifically, as shown in Fig. 19, in the separation device, a fluid is supplied between the wafer W and the tray T through a through-hole formed in the stage and a through-hole 101h formed in the disk portion 101 of the tray T, thereby floating the wafer W from the tray T. In this state, by using the lift pins shown in Fig. 18, the tray T and the wafer W can be easily separated. Alternatively, by holding the outer edge of the wafer W with a transfer mechanism in this state, the wafer W can be carried out of the separation device. The fluid supplied to the recess 103 can be an inert gas (for example, N ２ Gas) and ionic liquids can be used.

[0087] (3) Separation of Tray When loading / unloading the wafer W onto / from the tray T, the tray T may be configured so that the wafer W can be loaded / unloaded from the annular portion 102 of the tray T into / from the recess 103 of the tray T.

[0088] Specifically, for example, as shown in Fig. 20(a), the annular portion 102 of the tray T may be divided so as to be movable (lifted up) in the vertical direction relative to the disk portion 101. Then, by lifting up the annular portion 102 and, in this state, sliding the wafer W relative to the recess 103 as shown in Fig. 20(b), the wafer W can be loaded onto / detached from the tray T.

[0089] (4) Other Methods for Dividing the Tray In the example of (3) above, the annular portion 102 of the tray T is divided, but at least a part of the disk portion 101 may be divided instead of the annular portion 102.

[0090] 21, a part or all of the disk portion 101 of the tray T may be divided so as to be vertically buffer-driven (lifted up). In other words, a part of the tray T (particularly the disk portion 101) may be divided. Then, this divided portion 101p is lifted up by a lift pin, and in this state, a transfer arm of a transfer mechanism provided outside the loading / separating device is inserted onto the backside of the wafer W, thereby loading / separating the wafer W onto / from the tray T.

[0091] When forming the disc portion 101 of the tray T by dividing it into parts, it is desirable to select sheet heat transfer materials, rather than liquid heat transfer materials, as the first heat transfer material 104 and the second heat transfer material 105 in order to prevent leakage when the divided portion 101p is lifted up. When sheet heat transfer materials are selected as the first heat transfer material 104 and the second heat transfer material 105 in this way, the first heat transfer material 104 and the second heat transfer material 105 may be divided to fit the shape of the divided portion 101p of the disc portion 101, as shown in Figure 21. Alternatively, the first heat transfer material 104 and the second heat transfer material 105 may not be divided, but may be an elastic sheet heat transfer material that can expand and contract in the vertical direction to fit the lift-up of the divided portion 101p, as shown in Figure 22. Furthermore, as shown in FIG. 23, for example, only one of the first heat transfer material 104 or the second heat transfer material 105 may be divided to match the shape of the divided portion 101p (in the illustrated example, only the second heat transfer material 105).

[0092] 21 to 23, a part of the disk portion 101 is divided and configured to be liftable as divided portion 101p, but as shown in Fig. 24, through holes 101h through which lift pins are inserted may be formed in part or all of the disk portion 101, and the wafer W may be lifted up by the lift pins via the first heat transfer material 104 or the second heat transfer material 105 (second heat transfer material 105 in the illustrated example). Therefore, the through holes 101h formed in the disk portion 101 of the tray T may be provided with divided portions 101p that can be buffer-driven, or divided portions 101p may be omitted.

[0093] 21 to 24, the through-hole 101h (divided portion 101p) for loading / separating the wafer W onto / from the tray T is disposed at only one location in the center of the circular plate portion 101, but the number of through-holes 101h (divided portions 101p) is not limited to this and they may be disposed at multiple locations (preferably three or more locations) within the surface of the circular plate portion 101. Furthermore, the shape of the through-hole 101h (divided portion 101p) is not particularly limited and any shape can be selected, such as a circular shape or a rectangular shape when viewed from above.

[0094] <Method of Transporting / Placing Tray on Electrostatic Chuck> Next, a method of transporting / placing the tray Tw configured as above onto the electrostatic chuck 13 in the wafer processing module 7 will be described.

[0095] (1) Use of Lift Pins When placing the tray Tw on the tray support surface of the electrostatic chuck 13, the lift pins 14a inserted through the through holes 12h, 13h can be used. That is, for example, in a state where the tray Tw is placed above the electrostatic chuck 13 by the second transport mechanism 8 (see also FIG. 3 ), the lift pins 14a are caused to protrude from the upper surface of the electrostatic chuck 13 through the through holes 12h, 13h, and the tray Tw is transferred from the second transport mechanism 8 to the upper ends of the lift pins 14a. Thereafter, the second transport mechanism 8 is retracted, and the lift pins 14a are lowered, so that the tray Tw can be transferred from the lift pins 14a to the tray support surface of the electrostatic chuck 13.

[0096] In this way, by supporting the underside of the tray Tw using the second transport mechanism 8 and the lift pins 14a and transporting / transferring the tray Tw, the tray Tw can be transferred onto the electrostatic chuck 13 without damaging the device layer formed on the surface of the wafer W mounted on the tray T.

[0097] (2) Holding the Tray from Above / Side Note that when transferring the wafer W to the electrostatic chuck 13, it is necessary to prevent damage to the device layer formed on the front surface of the wafer W, and in conventional wafer processing that does not use a tray T, it is necessary to transfer / transfer the wafer W while holding the back side of the wafer W as a rule. In this regard, in wafer processing according to this embodiment, the wafer W is transferred / transferred while being mounted on the tray T as described above. In addition, in this embodiment, the tray T has an annular portion 102 that is arranged radially outward of the wafer W.

[0098] Therefore, in wafer processing according to this embodiment, instead of supporting the underside of the tray Tw with the second transport mechanism 8 and the lift pins 14a as described above, the tray Tw may be held from the upper side or the side, and transported / transferred to / from the electrostatic chuck 13.

[0099] 25 , for example, the tray T may be transported by holding the annular portion 102 of the tray T carrying the wafer W from above using the second transport mechanism 8. In this case, because holding the annular portion 102 of the tray T prevents damage to the device layer formed on the surface of the wafer W, the second transport mechanism 8 may transport the tray T by physically holding the annular portion 102 of the tray T. The method for holding the tray T by the second transport mechanism 8 is not particularly limited, and any method such as magnets, vacuum suction, or electrostatic suction may be selected.

[0100] In this manner, in wafer processing according to the present embodiment in which wafers W to be processed are loaded on trays T and transported / transferred, holding the trays T eliminates the need for direct contact between the wafers W and the second transport mechanism 8, and therefore the trays Tw carrying the wafers W can be accessed from above to be held / transferred. Furthermore, because the trays Tw can be held from above in this manner, the trays Tw can be transferred to the electrostatic chuck 13 directly from the second transport mechanism 8 without the need for lift pins 14a as in the conventional method. Therefore, when the trays Tw are held from above or from the side in this manner, the lifter 14 for transferring the trays Tw to the electrostatic chuck 13 can be omitted, and the configuration of the wafer processing module 7 can be simplified.

[0101] <Method of Fixing Tray to Support Member> Next, a description will be given of an example of a method of fixing the tray Tw transported as described above to the support member 11 (electrostatic chuck 13) in the wafer processing module 7. As described above, the tray Tw is held on the tray support surface of the support member 11. However, in order to efficiently cool the wafer W by the heat transfer fluid flowing through the flow path 12a formed in the base 12, it is necessary to increase the pressing force (surface pressure) of the tray Tw against the electrostatic chuck 13. Therefore, in the following description, a method will be described in which the tray Tw is held on the electrostatic chuck 13 with a pressing force equal to or greater than its own weight in order to increase the cooling efficiency of the wafer W.

[0102] 2, an electrostatic electrode 13b for supporting the tray Tw is provided on the tray support surface of the electrostatic chuck 13 of the support member 11. The support member 11 can attract and hold the tray Tw by utilizing this electrostatic electrode 13b.

[0103] First, a case where the disk portion 101 of the tray T is made of a conductive material will be described. To attract and hold the tray T, first, as shown in FIG. 26( a), a voltage (positive (+) charge in the illustrated example) is applied to the electrostatic electrode 13b. This causes the electrostatic electrode 13b to be positively charged. When the electrostatic electrode 13b is positively charged, as shown in FIG. 26( b), charges of the opposite polarity (i.e., negative (−)) to the charge accumulated on the electrostatic electrode 13b are accumulated on the disk portion 101 of the tray T and the wafer W across the dielectric ceramic member 13a. This generates a Coulomb force between the tray T (wafer W) and the electrostatic electrode 13b, which attracts and holds the tray T on the tray support surface of the electrostatic chuck 13.

[0104] Furthermore, when the tray Tw is attracted and held by the electrostatic chuck 13 by Coulomb force in this manner, plasma can be generated in the wafer processing module 7 to increase the Coulomb force and thereby increase the attracting and holding force of the electrostatic chuck 13. Specifically, as shown in Fig. 26(c) , by generating plasma in the plasma processing space 10s, charges of the opposite polarity (i.e., negative (-)) to the charges accumulated on the electrostatic electrode 13b are transferred from the plasma to the disk portion 101 of the tray T and the wafer W. In other words, the charges can be compensated for from the plasma to increase the Coulomb force, and the tray Tw can be attracted and held more firmly.

[0105] Next, a case where the disc portion 101 of the tray T is made of an insulating material will be described. When the disc portion 101 of the tray T is made of an insulating material, a charging electrode 101b is disposed inside the disc portion 101. When attracting and holding the tray T, first, as shown in FIG. 27( a), a voltage (positive (+) charge in the illustrated example) is applied to the electrostatic electrode 13b. This causes the electrostatic electrode 13b to be positively charged. When the electrostatic electrode 13b is positively charged, as shown in FIG. 27( b), charges of the opposite polarity (i.e., negative (−)) to the charge accumulated on the electrostatic electrode 13b are accumulated on the charging electrode 101b disposed on the disc portion 101 and the wafer W, across the ceramic member 13a, which is a dielectric, and the disc portion 101, which is an insulating member. As a result, a Coulomb force is generated between the charging electrode 101 b (wafer W) and the electrostatic electrode 13 b as opposite poles, and the tray Tw is attracted and held by the tray support surface of the electrostatic chuck 13 .

[0106] Furthermore, even when the disk portion 101 of the tray T is made of an insulating material, by generating plasma in the wafer processing module 7, the Coulomb force can be increased, thereby increasing the attracting and holding force of the electrostatic chuck 13. Specifically, as shown in FIG. 27( c), by generating plasma in the plasma processing space 10s, charges of the opposite polarity (i.e., negative (−)) to the charge accumulated on the electrostatic electrode 13b are transferred from the plasma to the charging electrode 101b and the wafer W. In other words, the charges can be compensated for from the plasma, increasing the Coulomb force, and the tray Tw can be more firmly attracted and held.

[0107] In this way, whether the disk portion of the tray T is made of a conductive material or an insulating material, the tray Tw can be appropriately attracted and held on the tray support surface by applying a voltage to the electrostatic electrode 13b of the electrostatic chuck 13. In addition, at this time, by generating plasma in the plasma processing space 10s, the Coulomb force between the tray Tw and the electrostatic chuck 13 is increased, and the tray Tw can be more firmly attracted and held.

[0108] Furthermore, by utilizing the Coulomb force in this manner, the attracting and holding of the tray Tw can be controlled simply by controlling the voltage applied to the electrostatic electrode 13b. Therefore, the tray Tw can be attracted and held without complicating the structure of the support member 11. Furthermore, since the attracting and holding can be performed simply by controlling the voltage in this manner, controllability is good, and the attracting force within the surface of the tray Tw can be made uniform, i.e., the surface pressure of the tray Tw against the electrostatic chuck 13 can be controlled uniformly, thereby improving the cooling efficiency of the wafer W and increasing the reproducibility of this attracting force.

[0109] 26 and 27, the tray Tw is electrostatically attracted by the electrostatic chuck 13 of the support member 11, but the method of holding the tray Tw on the support member 11 is not limited to this. Therefore, in the wafer processing module 7, the support member 11 does not necessarily have to be equipped with the electrostatic chuck 13.

[0110] 28 , a plurality of pin members 130, for example, two or more pin members 130 may be provided on the underside of the tray T, and the pin members 130 may be inserted into fixing holes formed in the support member 11, and then the tray T and the support member 11 may be mechanically held / fixed together by a locking mechanism 131. The pin members 130 and the locking mechanism 131 are preferably configured such that the pin members 130 are pulled into the fixing holes (support member 11) when the tray T is fixed (locked) to the support member 11, and the pin members 130 are pushed up against the fixing holes (support member 11) when the tray T is detached (unlocked). In this manner, locking the pin members 130 provided on the tray T to the support member 11 increases the adhesion (surface pressure) between the tray T and the support member 11 (electrostatic chuck 13), improving heat transfer and improving the cooling efficiency of the wafer W.

[0111] The structure of the locking mechanism 131 is not particularly limited as long as it can improve the adhesion between the support member 11 (electrostatic chuck 13) and the tray T when fixing (locking) the tray T. One example of the locking mechanism 131 is a clamp chuck mechanism, which may include a tapered pull-in member 131a for pulling in the pin members 130 and a tapered push-out member 131b for pushing out the pin members 130, which are moved in the horizontal direction by a slide mechanism 131c, as shown in FIG.

[0112] Alternatively, for example, the locking mechanism 131 may be a ring rotation mechanism configured to rotate circumferentially relative to the pin member 130 after the pin member 130 is inserted into the fixing hole, as shown in FIG. 29 . In this case, the rotation mechanism that rotates the tray T and the support member 11 relative to each other may be a motor. Furthermore, the ring rotation mechanism may rotate only the locking mechanism 131 relative to the pin member 130, or may rotate the entire support member 11 relative to the pin member 130. When only the locking mechanism 131 is configured to be rotatable, the structure of the locking mechanism 131 can be made smaller. When the entire support member 11 is configured to be rotatable, the structure of the locking mechanism 131 becomes larger. However, when supplying liquid heat transfer material through the above-described through holes 12h and 13h, the rotation allows the through holes 12h and 13h to move circumferentially between when the tray T is transferred and when the liquid heat transfer material is supplied. In other words, both the transfer of tray T and the supply of liquid heat transfer material can be achieved without shifting the position of through hole 101h formed in tray T circumferentially and / or radially from the formation positions of through holes 12h and 13h.

[0113] (3) Magnetic Force Holding Also, for example, the tray Tw may be attracted and held to the support member 11 by magnetic force.

[0114] 30 , magnets 102m and 11m are arranged inside the annular portion 102 of the tray T and on the outer periphery (opposite the annular portion 102) of the support member 11 corresponding to the annular portion 102. Electromagnets or permanent magnets can be selected as the magnets 102m and 11m arranged inside the annular portion 102 and the support member 11. By arranging the tray Tw above the support member 11 on which the magnet 11m is arranged so that the magnet 11m faces the magnet 102m, a magnetic force is generated between the magnet 11m and the magnet 102m as opposite poles, and the tray Tw can be attracted and held on the support member 11.

[0115] 30, a demagnetizer 140 is configured to be freely inserted into and removed from between the annular portion 102 of the tray Tw and the outer periphery of the support member 11. By disposing the demagnetizer 140 between the annular portion 102 and the support member 11, the magnetic force generated between the magnet 11m and the magnet 102m is canceled, and the tray Tw can be transported from the tray support surface of the support member 11.

[0116] In this way, in the wafer processing module 7 according to this embodiment, magnets may be disposed inside the tray T and the support member 11, respectively, so that the tray T can be attracted and held by the support member 11.

[0117] (4) Vacuum Adsorption The support member 11 of the wafer processing module 7 may be provided with a vacuum chuck instead of the electrostatic chuck 13. In this case, it is desirable to select an elastic sheet heat transfer material as the second heat transfer material 105 disposed at least on the underside of the tray T.

[0118] 31(a), for example, through holes 105h are formed in a second heat transfer material 105 (sheet heat transfer material) disposed on the underside of the tray T at positions corresponding to the vacuum lines 11v formed on the support member 11 in a plan view. Then, as shown in FIG. 31(b), by starting a vacuum pump connected to the vacuum line 11v, the tray Tw is attracted and held on the tray support surface of the support member 11 by vacuum force.

[0119] In addition, at this time, by selecting an elastic sheet heat transfer material as second heat transfer material 105, second heat transfer material 105 is compressed in the thickness direction as tray T is pressed against the tray support surface by vacuum force. In this manner, through holes 105h are closed by plastic deformation of second heat transfer material 105, and the entire surfaces of tray T and support member 11 come into contact with each other via second heat transfer material 105, thereby enabling appropriate vacuum suction of tray T and improving the cooling efficiency of wafers W placed on tray T.

[0120] <Method of Detaching Tray from Electrostatic Chuck> Next, an example of a method of detaching the tray Tw fixed to the support member 11 (electrostatic chuck 13) from the support member 11 will be described.

[0121] As described above, the support member 11 according to this embodiment is provided with the lifter 14, and the lift pins 14a support the tray Tw from below, enabling it to be detached from the tray support surface of the support member 11 (electrostatic chuck 13). However, when detaching the tray Tw from the support member 11 using the lift pins 14a, there is a concern that the tray Tw may not be easily peeled off from the tray support surface due to, for example, residual suction or vacuum suction. If the tray Tw is raised by the lift pins 14a in such a state where residual suction or the like exists, there is a concern that the tray T or the wafer W may be damaged due to an overload.

[0122] Therefore, in the wafer processing module 7 according to this embodiment, in order to suppress damage due to the overload caused by the lift-up, an inert gas (e.g., N ２32 , an inert gas supply flow path 151 connected to a gas supply unit 150 having a gas supply source is added to the through-holes 12h and 13h through which the lift pins 14a for raising and lowering the tray Tw are inserted. When the tray Tw is to be removed, the supply of the inert gas is started before the lift pins 14a raise the tray Tw, thereby pressurizing the interface between the tray Tw and the support member 11, thereby assisting in the removal of the tray Tw from the support member 11. The gas supply unit 150 may be used in common with the gas supply unit 20 shown in FIG. 2 .

[0123] According to this embodiment, by supplying an inert gas when the tray Tw is removed from the support member 11, the tray Tw can be easily removed.

[0124] As described above, the support member 11 has three through holes 12h, 13h for inserting the lift pins 14a (three in this embodiment), and the inert gas for removing the tray Tw may be supplied to at least one of these through holes 12h, 13h. ２ However, the gas to be supplied is not limited to an inert gas as long as the interface between the tray Tw and the support member 11 can be appropriately pressurized under vacuum. Specifically, for example, the above-mentioned ionic liquid may be supplied to the interface between the tray Tw and the support member 11 when the tray Tw is removed.

[0125] <Effects of the Technique of the Present Disclosure> As described above, in the wafer processing system 1 according to the technique of the present disclosure, a wafer W to be processed is loaded onto a tray T, and the tray T and wafer W are transported and processed together. As an example of the configuration of this tray T, as shown in FIG. 7 , a disk portion 101 serving as a base and an annular portion 102 serving as a peripheral portion are separate bodies. As shown in FIG. 12 , only the annular portion 102 serving as the peripheral portion can be raised and lowered. This allows both the transport of the wafer W and the driving (raising and lowering) of the annular portion 102 to be achieved with a reduced number of drive mechanisms. Conventional edge rings used in plasma processing sometimes require separate pins for transporting the wafer W and for driving the edge ring, which can lead to problems such as an increase in temperature singularities and increased costs. However, these problems are resolved.

[0126] 12 and 13, the lift pins 202 are arranged on the outer periphery of the wafer W, rather than directly below the wafer W. This prevents temperature singularities that may occur directly below the wafer W, and improves temperature uniformity and electric field uniformity.

[0127] 14 and 15, the light source 212 irradiates the annular portion 102, which serves as the peripheral portion, with light L, and the thickness of the annular portion 102 can be measured. This makes it possible to grasp the amount of wear of the annular portion 102. In particular, even if the annular portion 102 is thin, precise wear management is possible, and the management criteria can be clearly set. By enabling precise wear management of the annular portion 102, it is possible to appropriately control the product quality of the outer periphery of the wafer.

[0128] 16 and 17, the tray T and the wafer W are transported together by the lift pins 202, and DC power is supplied from the DC power source 32 to the annular portion 102 serving as the peripheral portion via the lift pins 202. This allows for appropriate sheath control at the edge of the wafer W, thereby enabling appropriate control of the product quality at the outer periphery of the wafer.

[0129] Furthermore, in the wafer processing module 7 according to the technology of the present disclosure, the pressing force (surface pressure) of the tray T against the tray support surface of the support member 11 is improved by electrostatic adsorption or clamping as described above, which further improves the heat transfer performance from the wafer W to the support member 11, thereby further appropriately improving the cooling efficiency of the wafer W.

[0130] In the above description, the wafer processing module 7 is a plasma processing module that performs plasma processing such as etching on wafers W. However, the wafer processing performed in wafer processing module 7 is not limited to plasma processing, and the technology disclosed herein can be applied to any processing that requires ensuring temperature uniformity and electric field uniformity, including at the outer periphery of the wafer W to be processed.

[0131] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. For example, the components of the above-described embodiments may be arbitrarily combined. Such an arbitrary combination naturally provides the functions and effects of each of the components involved in the combination, and also provides other functions and effects that are apparent to those skilled in the art from the description of this specification.

[0132] Furthermore, the effects described herein are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that are apparent to those skilled in the art from the description of this specification, in addition to or in place of the above-described effects.

[0133] REFERENCE SIGNS LIST 1 wafer processing system 10 plasma processing chamber 11 support member 101 disk portion (base portion) 102 annular portion (periphery) 103 recess T tray Tw tray (with wafer mounted) W wafer

Claims

1. A substrate processing apparatus for processing substrates, comprising: a processing chamber; and a support member disposed within the processing chamber and having a tray support surface on an upper surface thereof for supporting a tray, wherein the tray includes a base portion and a peripheral portion that forms a recess on the upper surface of the base portion for accommodating the substrate, and wherein the base portion and the peripheral portion are configured as separate entities.

2. A substrate processing apparatus as described in claim 1, comprising: a control unit; and lift pins that raise and lower the tray above the support member, wherein the control unit raises and lowers the base portion and / or the peripheral portion using the lift pins.

3. The substrate processing apparatus according to claim 2, wherein the lift pins are formed of a conductive material, and a power supply that supplies DC power to the peripheral edge portion is electrically connected to the lift pins.

4. The substrate processing apparatus according to any one of claims 1 to 3, wherein the base portion and the peripheral portion are formed of different materials.

5. The substrate processing apparatus according to claim 1, further comprising a light source that irradiates the peripheral edge portion with light, and wherein the support member and the base portion are provided with a transmission path that transmits the light irradiated from the light source.

6. A substrate processing apparatus as described in claim 5, wherein the light source is an optical sensor that receives and detects reflected light reflected by the upper surface of the peripheral portion and reflected light reflected by the lower surface of the peripheral portion, and measures the thickness of the peripheral portion based on the phase difference between these reflected lights.

7. A tray supported by a support member disposed in a processing chamber for processing a substrate, the tray including a base portion and a peripheral portion that forms a recess in the upper surface of the base portion for accommodating the substrate, the base portion and the peripheral portion being configured as separate bodies.

8. The tray of claim 7, wherein said base portion and said peripheral portion are formed from different materials.

9. A tray according to claim 7 or 8, wherein the base portion is provided with a transmission path for transmitting light emitted from a light source.

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