Substrate processing apparatus and substrate support section

Abstract

To increase the temperature control efficiency of a substrate support part.SOLUTION: A substrate processing apparatus includes: a processing container; a substrate support part which is arranged in the processing container; and a power source which supplies RF power to at least the substrate support part. The substrate support part includes: an electrostatic chuck which is formed by ceramics and holds a processing object substrate by electrostatic attraction; a base which has a flow path through which a heat exchange medium flows and supports the electrostatic chuck; a low linear expansion coefficient member which is provided between the electrostatic chuck and the base; a heat transfer sheet which is provided between the low linear expansion coefficient member and the base; a fixation part which fixes the heat transfer sheet to the low linear expansion coefficient member; and a conductive member which is provided between the low linear expansion coefficient member and the base and electrically connects the low linear expansion coefficient member with the base.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus and a substrate support unit.

Background Art

[0002] By flowing a temperature-controlled heat exchange medium from a chiller unit through the flow path of the substrate support unit, the substrate to be processed on the electrostatic chuck is cooled to a desired temperature. For example, Patent Document 1 proposes a substrate processing apparatus having a substrate support unit on which a substrate to be processed is placed. The substrate support unit includes a base on which a flow path through which a temperature-controlled heat exchange medium flows is arranged, and an electrostatic chuck that encloses an electrode within ceramics having high plasma resistance and places the substrate to be processed on the placement surface, and has a structure in which the base and the electrostatic chuck are adhered with an adhesive layer.

[0003] In recent years, the high-frequency power applied to the substrate support unit has been increasing. For this reason, the heat input from the plasma to the substrate to be processed increases, and the temperature control of the substrate to be processed may become insufficient.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure provides a technique capable of enhancing the temperature control efficiency of a substrate support unit.

Means for Solving the Problems

[0006] According to one aspect of the present disclosure, a substrate processing apparatus comprising a processing container, a substrate support portion disposed within the processing container, and a power supply for supplying RF power to at least the substrate support portion, wherein the substrate support portion comprises an electrostatic chuck formed of ceramics for holding a substrate to be processed by electrostatic adsorption, a base having a channel through which a heat exchange medium flows and supporting the electrostatic chuck, a low coefficient of thermal expansion member provided between the electrostatic chuck and the base, a heat transfer sheet provided between the low coefficient of thermal expansion member and the base, a fixing portion for fixing the heat transfer sheet to the low coefficient of thermal expansion member, and the low coefficient of thermal expansion member The aforementioned A low coefficient of thermal expansion member is provided between the base and the base. The aforementioned A substrate processing apparatus is provided, which includes a conductive member that electrically connects to a base. [Effects of the Invention]

[0007] From one perspective, it is possible to improve the temperature control efficiency of the substrate support section. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic cross-sectional view showing an example of a plasma processing apparatus according to one embodiment. [Figure 2] A diagram showing the configuration and reference examples of the substrate support portion according to the first and second embodiments. [Figure 3] Figure 1 is shown as a cross-section of plane AA. [Figure 4] A diagram showing an example of the electrode structure of the substrate support portion according to the first embodiment. [Figure 5] A diagram showing an example of the electrode structure of the substrate support portion according to the second embodiment. [Modes for carrying out the invention]

[0009] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0010] [Plasma treatment device] The configuration example of a plasma processing apparatus will be described below with reference to Figure 1. The plasma processing apparatus in Figure 1 is a capacitively coupled plasma processing apparatus 1 and includes a control unit 2. The plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10 (processing container), a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is located inside the plasma processing chamber 10. The shower head 13 is located above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, the side walls 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s, and at least one gas outlet for discharging gas from the plasma processing space 10s. The side wall 10a is grounded. The shower head 13 and the substrate support portion 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0011] The substrate support section 11 includes a base 122, a low coefficient of thermal expansion member 114, and an electrostatic chuck 111. The substrate support section 11 further includes a ring assembly 112. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring 112a. The electrostatic chuck 111 is positioned on the upper part of the base 122, sandwiching the low coefficient of thermal expansion member 114, and has a central region (substrate support surface 111a) for supporting the substrate (wafer) to be processed (hereinafter referred to as substrate W) and an annular region (ring support surface 111b) for supporting the edge ring 112a. The annular region (ring support surface 111b) of the electrostatic chuck 111 surrounds the central region (substrate support surface 111a) of the electrostatic chuck 111 in a plan view. The substrate W is placed on the substrate support surface 111a of the electrostatic chuck 111, and the edge ring 112a is placed on the ring support surface 111b of the electrostatic chuck 111 so as to surround the substrate W on the substrate support surface 111a of the electrostatic chuck 111. In one embodiment, the base 122 includes a conductive member. The conductive member of the base 122 functions as a lower electrode. The electrostatic chuck 111 is placed on the base 122 with a low coefficient of thermal expansion member 114 in between. The upper surface of the electrostatic chuck 111 has a substrate support surface 111a. The substrate support portion 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck 111, the edge ring 112a, and the substrate W to a target temperature. The temperature control module may include a flow path 123, a heater, a heat transfer medium, or a combination thereof. In this embodiment, the flow path 123 is formed in the base 122, but is not limited to this. A heat exchange medium flows through the flow path 123. The heat exchange medium is a liquid. The heat exchange medium, whose temperature is controlled by a chiller unit (not shown), flows through piping and through the channel 123 from the inlet IN of the substrate support unit 11, thereby cooling the substrate W on the electrostatic chuck 111 to the desired temperature. The heat exchange medium that has flowed through the channel 123 returns to the chiller unit through piping from the outlet OUT of the substrate support unit 11, where its temperature is controlled and it flows again through the channel 123 for circulation. The substrate support unit 11 may also include a heat transfer gas supply unit configured to supply heat transfer gas between the lower surface of the substrate W and the substrate support surface 111a.

[0012] The shower head 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of gas inlet ports 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s through the plurality of gas inlet ports 13c. The shower head 13 also includes a conductive member. The conductive member of the shower head 13 functions as an upper electrode. In addition to the shower head 13, the gas introduction unit may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 10a.

[0013] 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 processing gas to the shower head 13 from a corresponding gas source 21 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may include one or more flow modulation devices that modulate or pulse the flow rate of at least one processing gas.

[0014] 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), such as a source RF signal (RF source power) and a bias RF signal (RF bias power), to the conductive members of the substrate support 11 and / or the showerhead 13. This causes plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power supply 31 can function as at least part of a plasma generation unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. Furthermore, by supplying a bias RF signal to the conductive members of the substrate support 11, a bias potential is generated on the substrate W, and ionic components in the formed plasma can be drawn into the substrate W.

[0015] In one embodiment, the RF power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is coupled to a conductive member of the substrate support unit 11 and / or a conductive member of the shower head 13 via at least one impedance matching circuit and is configured to generate a source RF signal (RF source power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 13 MHz to 150 MHz. In one embodiment, the first RF generation unit 31a may be configured to generate a plurality of source RF signals having different frequencies. One or more generated source RF signals are supplied to the conductive member of the substrate support unit 11 and / or a conductive member of the shower head 13. The second RF generation unit 31b is coupled to a conductive member of the substrate support unit 11 via at least one impedance matching circuit and is configured to generate a bias RF signal (RF bias power). 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 400 kHz to 13.56 MHz. In one embodiment, the second RF generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated bias RF signals are supplied to the conductive member of the substrate support unit 11. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0016] In addition, the power supply 30 may include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generation unit 32a and a second DC generation unit 32b. In one embodiment, the first DC generation unit 32a is connected to a conductive member of the substrate support unit 11 and is configured to generate a first DC signal. The generated first DC signal (first bias DC signal) is applied to the conductive member of the substrate support unit 11. In one embodiment, the first DC signal may be applied to other electrodes such as the electrodes in the electrostatic chuck 111. In one embodiment, the second DC generation unit 32b is connected to a conductive member of the shower head 13 and is configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the shower head 13. In various embodiments, at least one of the first and second DC signals may be pulsed. Note that the first and second DC generation units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generation unit 32a may be provided in place of the second RF generation unit 31b.

[0017] The exhaust system 40 can be connected, for example, to a gas discharge port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is adjusted by the pressure regulating valve. The vacuum pump may include a turbo molecular pump, a dry pump, or a combination thereof.

[0018] The control unit 2 processes computer-executable instructions for causing the plasma processing apparatus 1 to execute various processes described in the present disclosure. The control unit 2 can be configured to control each element of the plasma processing apparatus 1 so as to execute the various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 can be configured to perform various control operations based on a program stored in the storage unit 2a2. The storage unit 2a2 may include a RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0019] [Substrate support unit] The configuration of the substrate support unit 11 will be further described with reference to FIGS. 1 to 3. FIG. 2 is a diagram showing the configuration of the substrate support unit 11 according to the first and second embodiments and the substrate support unit 11' of the reference example. FIG. 3 is a diagram obtained by cutting FIG. 1 along the line A-A and is a plan view of the base 122 as viewed from above.

[0020] FIG. 2(a) shows the substrate support unit 11' of the reference example, FIG. 2(b) shows a configuration example of the substrate support unit 11 according to the first embodiment, and FIG. 2(c) shows a configuration example of the substrate support unit 11 according to the second embodiment.

[0021] The substrate support unit 11' of the reference example shown in FIG. 2(a) has an electrostatic chuck 111 and a base 124. The electrostatic chuck 111 is formed of ceramics and has a suction electrode 111c inside. The electrostatic chuck 111 holds the substrate W by electrostatic adsorption by applying a DC voltage to the suction electrode 111c.

[0022] The base 124 is formed from a metal-ceramic composite material (MMC) with a low coefficient of thermal expansion and has a flow channel 123 inside. A metal bonding layer 113 is provided between the electrostatic chuck 111 and the base 124. The metal bonding layer 113 is used to metal-bond the electrostatic chuck 111 and the base 124 by metal brazing.

[0023] Even with the configuration of the substrate support section 11' in the reference example, the substrate W on the electrostatic chuck 111 is cooled to a desired temperature by flowing a heat exchange medium, whose temperature is controlled by the chiller unit, through the flow path 123 of the base 124. However, in recent years, the high-frequency power applied to the substrate support section has increased from the viewpoint of shortening the substrate processing time (etching time, etc.) and the straight-line propagation of ions. As a result, the heat input from the plasma to the substrate W increases, and the temperature control of the substrate W may become insufficient. If the temperature control of the substrate W is insufficient, processing efficiency such as etching may decrease due to the temperature rise of the substrate W, and the substrate W may be damaged by heat.

[0024] Therefore, the first and second embodiments shown in Figures 2(b) and (c) provide a substrate support unit 11 and a plasma processing apparatus 1 that can improve the temperature control efficiency of the substrate W.

[0025] <First Embodiment> (Example configuration) The substrate support portion 11 according to the first embodiment shown in Figure 2(b) includes an electrostatic chuck 111, a base 122, a low coefficient of thermal expansion member 114, a heat transfer sheet 130, a fixing portion 140, a metal bonding layer 113, and a conductive gasket 131.

[0026] The electrostatic chuck 111 is made of a dielectric material and has an adsorption electrode 111c inside. The electrostatic chuck 111 holds the substrate W on the substrate support surface 111a by electrostatic adsorption by applying a DC voltage (DC bias voltage, first bias DC signal) from the power supply 30 (DC power supply 32 in Figure 1) to the adsorption electrode 111c.

[0027] The base 122 is made of a non-magnetic metal material and has a flow channel 123 inside. A low coefficient of thermal expansion member 114 is provided between the electrostatic chuck 111 and the base 122.

[0028] The flow channel 123 formed in the base 122 opens at the upper surface of the base 122. The opening 123a on the upper surface of the flow channel 123 is blocked by the low coefficient of thermal expansion member 114. That is, the upper surface of the flow channel 123 is in contact with the lower surface of the low coefficient of thermal expansion member 114.

[0029] Figure 3 shows the upper surface of the base 122 (surface AA in Figure 1). A flow channel 123 is formed in a spiral shape on the base 122, and there is an opening 123a of the spiral flow channel 123 on the upper surface of the base 122. This allows the temperature of the substrate W to be controlled over the entire substrate support surface 111a of the substrate support part 11 (see Figure 1). Note that the shape of the flow channel 123 is not limited to a spiral shape; it may be radial or have other shapes.

[0030] The heat transfer sheet 130 is provided between the low coefficient of thermal expansion member 114 and the base 122. The heat transfer sheet 130 is a circular sheet and has an opening shaped the same as the opening 123a of the flow path 123. The diameter of the heat transfer sheet 130 is smaller than the diameters of the low coefficient of thermal expansion member 114 and the base 122, and the outermost circumference of the heat transfer sheet 130 is inward from the outermost circumference of the low coefficient of thermal expansion member 114 and the base 122. The heat transfer sheet 130 is a graphite sheet. The graphite sheet is formed from a resin material combining carbon and silicone and is a highly thermally conductive material. Therefore, as shown in Figure 3, the heat transfer sheet 130 is laid on the upper surface of the base 122 where the opening 123a of the flow path 123 is not formed. This increases the heat transfer efficiency between the low coefficient of thermal expansion member 114 and the base 122, and improves the cooling performance of the flow path 123.

[0031] The heat transfer sheet 130 may be an anisotropic heat transfer sheet containing graphite. That is, the heat transfer sheet 130 may be made of an anisotropic material such as graphite, which can ensure high thermal conductivity because the horizontal or vertical carbon crystal structure is strongly bonded by covalent bonds. This improves the horizontal or vertical heat conduction and enhances the in-plane temperature uniformity on the substrate W.

[0032] As shown in Figure 2, the fixing part 140 may have a screw structure including, for example, a plurality of screws 140a. The screws 140a are inserted into through holes that penetrate the base 122 in the thickness direction, and their tips are screwed into screw holes 114a formed in the low coefficient of thermal expansion member 114, thereby fixing the heat transfer sheet 130 to the low coefficient of thermal expansion member 114. The number and arrangement of the plurality of screws 140a are determined so as to evenly pressurize the entire surface of the heat transfer sheet 130. As a result, the heat transfer sheet 130 can achieve stable heat transfer between the base 122, the low coefficient of thermal expansion member 114, and the electrostatic chuck 111.

[0033] The fixing part 140 is not limited to a screw structure; other methods may be applied as long as the entire surface of the heat transfer sheet 130 can be evenly pressed and fixed to the low coefficient of thermal expansion member 114. For example, the fixing part 140 may have a clamp structure, and the heat transfer sheet 130 may be fixed to the low coefficient of thermal expansion member 114 by clamping the low coefficient of thermal expansion member 114 and the base 122.

[0034] If the low coefficient of thermal expansion member 114 and the base 122 are brought into solid-on-solid contact without the heat transfer sheet 130, a small gap will be created at the contact surface, increasing the thermal resistance and reducing heat transfer efficiency. Therefore, a heat transfer sheet 130 is provided between the low coefficient of thermal expansion member 114 and the base 122, and the entire surface of the heat transfer sheet 130 is further pressurized by the fixing part 140 to eliminate the gap that existed between the low coefficient of thermal expansion member 114 and the base 122, thereby lowering the thermal resistance and improving heat conduction. As a result, the heat transfer efficiency between the low coefficient of thermal expansion member 114 and the base 122 can be increased, the cooling performance by the flow path 123 can be enhanced, the temperature of the substrate W can be reduced, and the temperature of the substrate W can be controlled with precision.

[0035] A metal bonding layer 113 is provided between the electrostatic chuck 111 and the low coefficient of thermal expansion member 114. The metal bonding layer 113 is bonded (metal bonding) between the electrostatic chuck 111 and the base 122 by brazing (metal solder). This reduces the thermal resistance between the electrostatic chuck 111 and the low coefficient of thermal expansion member 114, improving heat conduction and further promoting temperature control of the substrate W. As a result, a substrate support part 11 having an electrostatic chuck 111 and a base 122 with high thermal conductivity can be provided.

[0036] As shown in Figure 2, a conductive gasket 131 is provided around the outer circumference of a heat transfer sheet 130 fixed between a base 122 and a low coefficient of thermal expansion member 114. A vacuum seal 132 is provided around the outer circumference of the conductive gasket 131. The vacuum seal 132 is, for example, an O-ring.

[0037] The conductive gasket 131 is provided between the low coefficient of thermal expansion member 114 and the base 122, electrically connecting the low coefficient of thermal expansion member 114 and the base 122. The vacuum seal 132 seals the plasma processing space 10s in a vacuum (reduced pressure) atmosphere from the space on the flow path 123 side. In addition, the vacuum seal 132 may have plasma resistance. This protects the conductive gasket 131 and the heat transfer sheet 130 from wear by the plasma generated in the plasma processing space 10s. The heat transfer sheet 130 is particularly susceptible to wear by plasma because it is a graphite sheet containing carbon. The conductive gasket 131 is made of metal. Therefore, sealing with the vacuum seal 132 can suppress wear of the conductive gasket 131 and the heat transfer sheet 130, thereby preventing the conductive gasket 131 and the heat transfer sheet 130 from becoming a source of contamination.

[0038] (Example of materials) The electrostatic chuck 111 is made of ceramics such as alumina (Al2O3) which has high plasma resistance. The base 122 has a volume resistivity of 10 -4 It may be formed from a material with a impedance of less than Ωm. In this case, power loss in the RF signal base 122 can be further reduced. For example, the base 122 may be aluminum, molybdenum, or titanium.

[0039] The low coefficient of thermal expansion member 114 may be formed from a material whose difference in coefficient of thermal expansion from that of the electrostatic chuck 111 is 2 ppm / °C or less. For example, the low coefficient of thermal expansion member 114 may be a metal matrix composite (MMC) or molybdenum. In this case, the difference in coefficient of thermal expansion between the base 122 and the low coefficient of thermal expansion member 114 can be further reduced, making it possible to suppress shear stress associated with temperature changes.

[0040] The conductive gasket 131 may be a spring-shaped conductive member or a spiral-shaped metal. The conductive gasket 131 is an example of a conductive member that electrically connects the low coefficient of thermal expansion member 114 and the base 122. The base 122 also functions as a lower electrode that supplies RF power. Therefore, when RF power is supplied to, for example, an aluminum base 122, the conductive gasket 131 is configured to conduct current to transmit the RF current to the low coefficient of thermal expansion member 114 and the electrostatic chuck 111 on the base 122. The conductive gasket 131 can form a conductive path between the base 122 and the electrostatic chuck 111.

[0041] The heat transfer sheet 130 contains a resin material that combines carbon and silicone to improve adhesion and heat transfer. Therefore, heat transfer sheets 130 with high adhesion and heat transfer tend to have low conductivity. Conversely, conductive gaskets 131 with high conductivity tend to have reduced heat transfer. Based on the above, the heat transfer sheet 130 with high adhesion and heat transfer is used, and the conductive gasket 131 is used to form a conductive path between the base 122 and the electrostatic chuck 111.

[0042] However, the conductive member electrically connecting the low coefficient of thermal expansion member 114 and the base 122 is not limited to a conductive gasket 131; a conductive screw 140a may be used, or both the conductive gasket 131 and the conductive screw 140a may be used. This enhances the cooling performance of the flow path 123 and improves the accuracy of temperature control of the substrate W.

[0043] Furthermore, in the substrate support portion 11 according to the first embodiment shown in Figure 2(b), the flow channel 123 is formed on the upper surface of the base 122. Therefore, the processing cost is lower compared to the reference example substrate support portion 11' shown in Figure 2(a), in which the flow channel 123 is formed inside the base 124. In addition, comparing the metal-ceramic composite material (MMC) base 124 in Figure 2(a) with the aluminum base 122 in Figure 2(b), the aluminum base 122 has the advantage of even lower processing costs because the flow channel 123 is easier to process.

[0044] <Second Embodiment> The basic configuration of the substrate support 11 according to the second embodiment shown in Figure 2(c) is the same as that of the substrate support 11 according to the first embodiment. In the substrate support 11 according to the first embodiment, the upper surface of the flow path 123 is blocked by the low coefficient of linear expansion member 114, whereas in the substrate support 11 according to the second embodiment, the upper surface of the flow path 123 is blocked by the upper part of the base 122. Therefore, this different configuration will be explained, and the explanation of other configurations will be omitted.

[0045] A fluorine-based heat exchange medium, such as brine, is passed through the flow path 123. Therefore, in the configuration of the substrate support section 11 according to the first embodiment, there is a possibility that the heat transfer sheet 130 may deteriorate due to direct contact between the brine and the heat transfer sheet 130.

[0046] In contrast, in the configuration of the substrate support 11 according to the second embodiment, the upper surface of the flow path 123 is blocked by the upper part of the base 122, so the brine does not come into direct contact with the heat transfer sheet 130, and deterioration of the heat transfer sheet 130 can be prevented. In addition, the presence of a base 122 made of a non-magnetic metal such as aluminum, which has high thermal conductivity (good thermal diffusion), on the flow path 123 makes it easier for heat to diffuse laterally. As a result, temperature uniformity is increased, and the occurrence of temperature singularities due to the arrangement and shape of the flow path 123 can be mitigated. Furthermore, comparing the metal-ceramic composite material (MMC) base 124 in Figure 2(a) with the aluminum base 122 in Figure 2(c), the aluminum base 122 has the advantage of lower processing costs because the flow path 123 is easier to process.

[0047] <Electrode Structures of the First and Second Embodiments> The power supply 30 may supply RF source power (source RF signal) and RF bias power (bias RF signal) or DC bias voltage to the base 122. To supply this power, electrode structures applicable to the substrate support 11 according to the first embodiment and the substrate support 11 according to the second embodiment will be described with reference to Figures 4 and 5. Figure 4 is a diagram showing an example of the electrode structure of the substrate support 11 according to the first embodiment. Figure 5 is a diagram showing an example of the electrode structure of the substrate support 11 according to the second embodiment.

[0048] As shown in Figures 4(a) to 4(c) and Figures 5(a) to 5(c), the electrostatic chuck 111 may have a first portion 111f having a substrate support surface 111a that supports the substrate W, and a second portion 111s having a ring support surface 111b that supports the edge ring 112a. There is an annular gap 111g between the first portion 111f and the second portion 111s of the electrostatic chuck 111, and the first portion 111f and the second portion 111s of the electrostatic chuck 111 are separated.

[0049] The first portion 111f of the electrostatic chuck 111 is provided with an adsorption electrode 111c and a first bias electrode 111e located below the adsorption electrode 111c. The second portion 111s of the electrostatic chuck 111 is provided with an adsorption electrode 111d and a second bias electrode 111h located below the adsorption electrode 111d.

[0050] The depth of the annular gap 111g is shallowest in the substrate support portion 11 in Figures 4(b) and 5(b), deepest in the substrate support portion 11 in Figures 4(a) and 5(a), and intermediate in depth in the substrate support portion 11 in Figures 4(c) and 5(c). However, it is not limited to this. The annular gap 111g may extend from the lower surface of the base 122 to either the substrate support surface 111a or the ring support surface 111b.

[0051] In the substrate support portion 11 shown in Figures 4(b) and 5(b), the metal bonding layer 113 is configured to be separated in accordance with the separation position of the first portion 111f and the second portion 111s of the electrostatic chuck 111. As a result, the depth of the gap 111g becomes equal to the bottom surface of the metal bonding layer 113.

[0052] In the substrate support portion 11 of Figures 4(c) and 5(c), the low coefficient of thermal expansion member 114 is further configured to be separated in accordance with the separation position of the metal bonding layer 113. As a result, the depth of the gap 111g becomes equal to the lower surface of the low coefficient of thermal expansion member 114. In this case, a conductive gasket 131a and a vacuum seal 132a are provided around the outer circumference of the heat transfer sheet 130 below the first portion 111f of the electrostatic chuck 111, surrounding the heat transfer sheet 130. In addition, a conductive gasket 131b and a vacuum seal 132b are provided around the outer circumference of the heat transfer sheet 130 below the second portion 111s of the electrostatic chuck 111, surrounding the heat transfer sheet 130. This protects the conductive gasket 131a, conductive gasket 131b, and heat transfer sheet 130 from wear caused by the plasma generated in the plasma processing space 10s.

[0053] In the substrate support portion 11 shown in Figures 4(a) and 5(a), the base 122 is further configured to separate in accordance with the separation position of the low coefficient of thermal expansion member 114. This makes the depth of the gap 111g equal to the bottom surface of the base 122. In this case, a conductive plate 125 is provided at the bottom of the base 122 to close the gap 111g. Also, a conductive gasket 131a and a vacuum seal 132a are provided around the outer circumference of the heat transfer sheet 130 below the first portion 111f of the electrostatic chuck 111, surrounding the heat transfer sheet 130. A conductive gasket 131b and a vacuum seal 132b are provided around the outer circumference of the heat transfer sheet 130 below the second portion 111s of the electrostatic chuck 111, surrounding the heat transfer sheet 130. Furthermore, a vacuum seal 132c is provided on the inner circumference of the heat transfer sheet 130 below the second portion 111s of the electrostatic chuck 111, surrounding the heat transfer sheet 130. This protects the conductive gasket 131a, conductive gasket 131b, and heat transfer sheet 130 from wear caused by the plasma generated in the plasma processing space 10s.

[0054] As shown in Figure 1, the first part 111f and the second part 111s of the electrostatic chuck 111 may be integrated. In both cases, whether the electrostatic chuck 111 is integrated or separated (see Figures 4 and 5), the power supply 30 supplies RF power to the base 122. The RF power supplied to the base 122 may be RF source power, RF bias power, or both RF source power and RF bias power. In both cases, whether the electrostatic chuck 111 is integrated or separated, RF bias power or a DC bias voltage can be supplied to the electrodes provided in the first part 111f and / or the second part 111s of the electrostatic chuck 111.

[0055] As a first example of supplying RF power and / or DC voltage, in an integrated electrostatic chuck 111 (see Figure 1), RF source power and RF bias power may be supplied from the power supply 30 to the base 122. In this case, a DC voltage may be supplied to the adsorption electrode 111c, and the substrate W may be electrostatically adsorbed to the electrostatic chuck 111. Alternatively, a DC voltage may be supplied to the adsorption electrode 111c and the adsorption electrode 111d, respectively, and the substrate W and the edge ring 112a may be electrostatically adsorbed to the electrostatic chuck 111, respectively.

[0056] As a second example, RF source power and RF bias power may be supplied to the base 122 in a separate electrostatic chuck 111 (see Figures 4 and 5). In this case, DC voltages may be supplied to the adsorption electrodes 111c and 111d, respectively, and the substrate W and edge ring 112a may be electrostatically adsorbed to the electrostatic chuck 111, respectively.

[0057] As a third example, in an integrated electrostatic chuck 111 (see Figure 1), RF source power and DC bias power of a pulsed wave may be supplied from the power supply 30 to the base 122. In this case, a DC voltage may be supplied to the adsorption electrode 111c, and the substrate W may be electrostatically adsorbed to the electrostatic chuck 111.

[0058] As a fourth example, in an integrated electrostatic chuck 111 (see Figure 1), RF source power may be supplied from the power supply 30 to the base 122, and pulsed DC bias power may be supplied to the first bias electrode 111e. In this case, a DC voltage may be supplied to the adsorption electrode 111c, and the substrate W may be electrostatically adsorbed to the electrostatic chuck 111.

[0059] As a fifth example, in an integrated electrostatic chuck 111 (see Figure 1), RF source power may be supplied from the power supply 30 to the base 122, and pulsed DC bias power (first DC bias power) may be supplied to the first bias electrode 111e. Alternatively, pulsed DC bias power (second DC bias power) may be supplied to the second bias electrode 111h. In this case, DC voltages may be supplied to the adsorption electrodes 111c and 111d, respectively, and the substrate W and edge ring 112a may be electrostatically adsorbed to the electrostatic chuck 111, respectively.

[0060] As a sixth example, in a separated electrostatic chuck 111 (see Figures 4 and 5), RF source power may be supplied from the power supply 30 to the base 122, and pulsed DC bias power (first DC bias power) may be supplied to the first bias electrode 111e. Alternatively, pulsed DC bias power (second DC bias power) may be supplied to the second bias electrode 111h. In this case, DC voltages may be supplied to the adsorption electrodes 111c and 111d, respectively, and the substrate W and edge ring 112a may be electrostatically adsorbed to the electrostatic chuck 111, respectively.

[0061] As a seventh example, in an integrated electrostatic chuck 111 (see Figure 1), RF source power and pulse wave DC bias power (first DC bias power) may be supplied from the power supply 30 to the base 122. Alternatively, pulse wave DC bias power (second DC bias power) may be supplied to the second bias electrode 111h. In this case, DC voltages may be supplied to the adsorption electrodes 111c and 111d, respectively, and the substrate W and edge ring 112a may be electrostatically adsorbed to the electrostatic chuck 111, respectively.

[0062] As an eighth example, in a separated electrostatic chuck 111 (see Figures 4 and 5), RF source power and pulse wave DC bias power (first DC bias power) may be supplied from the power supply 30 to the base 122. Alternatively, pulse wave DC bias power (second DC bias power) may be supplied to the second bias electrode 111h. In this case, DC voltages may be supplied to the adsorption electrodes 111c and 111d, respectively, and the substrate W and edge ring 112a may be electrostatically adsorbed to the electrostatic chuck 111, respectively.

[0063] As a ninth example, in an integrated electrostatic chuck 111 (see Figure 1), RF source power and DC bias power of a pulsed wave may be supplied from the power supply 30 to the base 122. In this case, DC voltage may be supplied to the adsorption electrodes 111c and 111d, respectively, and the substrate W and edge ring 112a may be electrostatically adsorbed to the electrostatic chuck 111, respectively.

[0064] According to the substrate support portion 11 of the first and second embodiments and the substrate processing apparatus having these substrate support portions 11, the heat transfer efficiency between the low coefficient of linear expansion member 114 and the base 122 can be increased. This enhances the cooling performance by the flow path 123, promotes a decrease in the temperature of the substrate W, and allows for precise control of the temperature of the substrate W. Furthermore, the processing cost can be reduced compared to the substrate support portion 11' of the reference example shown in Figure 2(a).

[0065] In the above embodiment, the cooling of the substrate W using a heat exchange medium was mainly described, but the same applies to temperature control such as heating the substrate W using a heat exchange medium, which promotes the temperature rise (temperature control) of the substrate W and allows for precise control of the substrate W's temperature.

[0066] The embodiments disclosed above include, for example, the following aspects: (Note 1) A substrate processing apparatus comprising a processing container, a substrate support unit disposed within the processing container, and a power supply that supplies RF power to at least the substrate support unit, The substrate support portion is, An electrostatic chuck formed from ceramics that holds the substrate to be processed by electrostatic adsorption, A base having a flow path through which a heat exchange medium flows, and supporting the electrostatic chuck, A low coefficient of thermal expansion member is provided between the electrostatic chuck and the base, A heat transfer sheet is provided between the low coefficient of thermal expansion member and the base, A fixing part for fixing the heat transfer sheet to the low coefficient of thermal expansion member, The low coefficient of thermal expansion member and The aforementioned A low coefficient of thermal expansion member is provided between the base and the base. The aforementioned A conductive member that electrically connects to the base, A substrate processing apparatus having (Note 2) The upper surface of the flow path is blocked by the low coefficient of thermal expansion member. The substrate processing apparatus described in Appendix 1. (Note 3) The upper surface of the aforementioned flow path is blocked by the upper part of the base. The substrate processing apparatus described in Appendix 1. (Note 4) The electrostatic chuck and the low coefficient of thermal expansion member have a metal bonding layer that provides metal bonding between them. A substrate processing apparatus as described in any one of the appendices 1 to 3. (Note 5) The aforementioned fixing part has a screw structure or a clamp structure. A substrate processing apparatus as described in any one of the appendices 1 to 4. (Note 6) The low coefficient of thermal expansion member is formed from a material whose coefficient of thermal expansion differs from that of the electrostatic chuck by 2 ppm / °C or less. A substrate processing apparatus as described in any one of the appendices 1 to 5. (Note 7) The low coefficient of thermal expansion member is a metal-ceramic composite material or molybdenum. A substrate processing apparatus as described in any one of the appendices 1 to 6. (Note 8) The aforementioned base has a volume resistivity of 10 -4 Ωm Formed from less than a certain material, A substrate processing apparatus as described in any one of the appendices 1 to 7. (Note 9) The base is made of aluminum, molybdenum, or titanium. A substrate processing apparatus as described in any one of the appendices 1 to 8. (Note 10) The heat transfer sheet is a graphite sheet. A substrate processing apparatus as described in any one of the appendices 1 to 9. (Note 11) The power supply provides RF source power and RF bias power or DC bias voltage to the base. A substrate processing apparatus as described in any one of the appendices 1 to 10. (Note 12) The electrostatic chuck comprises a first portion having a substrate support surface for supporting the substrate to be processed, and an edge ring arranged to surround the substrate to be processed. support It has a second part having a ring support surface, The power supply provides RF source power to the base and RF bias power or DC bias voltage to the electrodes provided on the first and / or second portions of the electrostatic chuck. A substrate processing apparatus as described in any one of the appendices 1 to 11. (Note 13) The first and second parts of the electrostatic chuck are integrated. The substrate processing apparatus described in Appendix 12. (Note 14) The first and second parts of the electrostatic chuck are separated. The substrate processing apparatus described in Appendix 12. (Note 15) The electrostatic chuck comprises a first portion having a substrate support surface for supporting the substrate to be processed, and a second portion having a ring support surface for supporting an edge ring arranged to surround the substrate to be processed. The power supply provides RF source power to the base and RF bias power or DC bias voltage to the electrodes provided on the first and / or second parts of the electrostatic chuck. The first and second parts of the electrostatic chuck are separated, The metal bonding layer is configured to separate in accordance with the separation position between the first and second portions of the electrostatic chuck. Note 4 The substrate processing apparatus described above. (Note 16) The low coefficient of thermal expansion member is configured to separate in accordance with the separation position of the metal bonding layer. The substrate processing apparatus described in Appendix 15. (Note 17) The base is configured to separate in accordance with the separation position of the low coefficient of thermal expansion member. The substrate processing apparatus described in Appendix 16. (Note 18) A substrate support portion disposed within a processing container in a substrate processing apparatus having a processing container, An electrostatic chuck formed from ceramics that holds the substrate to be processed by electrostatic adsorption, A base having a flow path through which a heat exchange medium flows, and supporting the electrostatic chuck, A low coefficient of thermal expansion member is provided between the electrostatic chuck and the base, A heat transfer sheet is provided between the low coefficient of thermal expansion member and the base, A fixing part for fixing the heat transfer sheet to the low coefficient of thermal expansion member, The low coefficient of thermal expansion member and The aforementioned A low coefficient of thermal expansion member is provided between the base and the base. The aforementioned A conductive member that electrically connects to the base, A substrate support section having the following features.

[0067] It should be noted that the present invention is not limited to the configurations shown in the above embodiments, including combinations with other elements. These points can be modified without departing from the spirit of the invention and can be appropriately determined according to their application. Furthermore, the matters described in the multiple embodiments can be combined with other configurations as long as they do not contradict each other.

[0068] For example, in the above embodiment, a capacitively coupled plasma processing apparatus was described as an example of a substrate processing apparatus, but it is not limited to this and may be applied to other plasma processing apparatuses. For example, an inductively coupled plasma (ICP) processing apparatus may be used instead of a capacitively coupled plasma processing apparatus. In this case, the inductively coupled plasma processing apparatus includes an antenna and a lower electrode. The lower electrode is located within the substrate support, and the antenna is located above or above the chamber. The RF generator is coupled to the antenna, and the DC generator is coupled to the lower electrode. Therefore, the RF generator is coupled to the upper electrode of the capacitively coupled plasma processing apparatus or to the antenna of the inductively coupled plasma processing apparatus. That is, the RF generator is coupled to the plasma processing chamber 10. [Explanation of Symbols]

[0069] 1. Plasma processing equipment 2 Control Unit 2a Computer 10 Plasma processing chamber 11. Substrate support section 20 Gas Supply Department 30 power supply 31 RF power supply 111 Electrostatic Chuck 112 Ring Assembly 112a Edge Ring 113 Metal bonding layer 114 Low coefficient of thermal expansion member 122 base 123 Flow Channel 130 Heat transfer sheet 131 Conductive gasket 140 Fixed part

Claims

1. A substrate processing apparatus comprising a processing container, a substrate support unit disposed within the processing container, and a power supply that supplies RF power to at least the substrate support unit, The substrate support portion is, An electrostatic chuck formed from ceramics that holds the substrate to be processed by electrostatic adsorption, A base having a flow path through which a heat exchange medium flows, and supporting the electrostatic chuck, A low coefficient of thermal expansion member is provided between the electrostatic chuck and the base, A heat transfer sheet is provided between the low coefficient of thermal expansion member and the base, A fixing part for fixing the heat transfer sheet to the low coefficient of thermal expansion member, A conductive member is provided between the low coefficient of thermal expansion member and the base, and electrically connects the coefficient of thermal expansion member and the base. It has, The upper surface of the flow path is blocked by the low coefficient of thermal expansion member. The power supply is a substrate processing device that supplies RF source power and RF bias power or DC bias voltage to the base.

2. A substrate processing apparatus comprising a processing container, a substrate support unit disposed within the processing container, and a power supply that supplies RF power to at least the substrate support unit, The substrate support portion is, An electrostatic chuck formed from ceramics that holds the substrate to be processed by electrostatic adsorption, A base having a flow path through which a heat exchange medium flows, and supporting the electrostatic chuck, A low coefficient of thermal expansion member is provided between the electrostatic chuck and the base, A heat transfer sheet is provided between the low coefficient of thermal expansion member and the base, A fixing part for fixing the heat transfer sheet to the low coefficient of thermal expansion member, A conductive member is provided between the low coefficient of thermal expansion member and the base, and electrically connects the coefficient of thermal expansion member and the base. It has, The upper surface of the flow path is blocked by the low coefficient of thermal expansion member. The electrostatic chuck comprises a first portion having a substrate support surface for supporting the substrate to be processed, and a second portion having a ring support surface for supporting an edge ring arranged to surround the substrate to be processed. The power supply is a substrate processing apparatus that supplies RF source power to the base and supplies RF bias power or DC bias voltage to electrodes provided on the first and / or second parts of the electrostatic chuck.

3. The first and second parts of the electrostatic chuck are integrated. The substrate processing apparatus according to claim 2.

4. The first and second parts of the electrostatic chuck are separated. The substrate processing apparatus according to claim 2.

5. The aforementioned fixing part has a screw structure or a clamp structure. A substrate processing apparatus according to any one of claims 1 to 4.

6. The low coefficient of thermal expansion member is formed from a material whose coefficient of thermal expansion difference from that of the electrostatic chuck is 2 ppm / °C or less. A substrate processing apparatus according to any one of claims 1 to 4.

7. The low coefficient of thermal expansion member is a metal-ceramic composite material or molybdenum. A substrate processing apparatus according to any one of claims 1 to 4.

8. The aforementioned base has a volume resistivity of 10 －４ Formed from a material with a thickness of less than Ωm, A substrate processing apparatus according to any one of claims 1 to 4.

9. The base is made of aluminum, molybdenum, or titanium. A substrate processing apparatus according to any one of claims 1 to 4.

10. The heat transfer sheet is a graphite sheet. A substrate processing apparatus according to any one of claims 1 to 4.

11. A substrate support portion disposed within a processing container in a substrate processing apparatus having a processing container, An electrostatic chuck formed from ceramics that holds the substrate to be processed by electrostatic adsorption, A base having a flow path through which a heat exchange medium flows, and supporting the electrostatic chuck, A low coefficient of thermal expansion member is provided between the electrostatic chuck and the base, A heat transfer sheet is provided between the low coefficient of thermal expansion member and the base, A fixing part for fixing the heat transfer sheet to the low coefficient of thermal expansion member, A conductive member is provided between the low coefficient of thermal expansion member and the base, and electrically connects the coefficient of thermal expansion member and the base. It has, The upper surface of the flow path is blocked by the low coefficient of thermal expansion member. A substrate support section to which RF source power and RF bias power or DC bias voltage are supplied to the base.

12. A substrate support portion disposed within a processing container in a substrate processing apparatus having a processing container, An electrostatic chuck formed from ceramics that holds the substrate to be processed by electrostatic adsorption, A base having a flow path through which a heat exchange medium flows, and supporting the electrostatic chuck, A low coefficient of thermal expansion member is provided between the electrostatic chuck and the base, A heat transfer sheet is provided between the low coefficient of thermal expansion member and the base, A fixing part for fixing the heat transfer sheet to the low coefficient of thermal expansion member, A conductive member is provided between the low coefficient of thermal expansion member and the base, and electrically connects the coefficient of thermal expansion member and the base. It has, The upper surface of the flow path is blocked by the low coefficient of thermal expansion member. The electrostatic chuck comprises a first portion having a substrate support surface for supporting the substrate to be processed, and a second portion having a ring support surface for supporting an edge ring arranged to surround the substrate to be processed. A substrate support portion to which RF source power is supplied to the base, and RF bias power or DC bias voltage is supplied to electrodes provided on the first and / or second portions of the electrostatic chuck.

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