Substrate mounting base, substrate processing device and substrate processing method

Abstract

To provide a substrate mounting base which is usable in a high-temperature process, and to provide a substrate processing device and a substrate processing method.SOLUTION: A substrate mounting base is installed inside of a processing container, in which processing is applied to a substrate, and the substrate is mounted thereon. The substrate mounting base comprises: an electrostatic chuck consisting of a base material including a dielectric layer with a built-in attraction electrode on a mounting surface on which the substrate is mounted; a heating plate consisting of aluminum or an aluminum alloy connected at a lower side of the electrostatic chuck; and a cooling plate consisting of the aluminum or the aluminum alloy connected at a lower side of the heating plate. A face of the heating plate corresponding to the cooling plate is defined as a first face, and a face of the cooling plate corresponding to the heating plate is defined as a second face. The substrate mounting base includes a gap space extending in a direction along the first face and the second face between the heating plate and the cooling plate and includes alumite coatings at least on any one of or both the first face exposed in the gap space and the second face exposed in the gap space.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a substrate mounting table, a substrate processing apparatus, and a substrate processing method. [Background technology]

[0002] Patent Document 1 describes a substrate holder that includes a heat exchange jacket through which a heat medium flows, a heat equalizing plate that reduces unevenness in temperature distribution on the flat heat exchange surface of the heat exchange jacket, and an electrostatic chuck having an attraction electrode embedded in an insulator, in which a carbon fluoride-based heat medium heated to about 170°C is transported to the heat exchange jacket, and the electrostatic chuck is uniformly heated via the heat equalizing plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 05-29300 Summary of the Invention [Problem to be solved by the invention]

[0004] In one aspect, the present disclosure provides a substrate mounting table, a substrate processing apparatus, and a substrate processing method that can be used in high-temperature processes. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, according to one aspect, there is provided a substrate mounting table that is installed inside a processing vessel in which a substrate is processed and that mounts the substrate thereon, the substrate mounting table having: an electrostatic chuck made of a base material having a dielectric layer with an adsorption electrode built in a mounting surface on which the substrate is mounted; a heating plate made of aluminum or an aluminum alloy connected below the electrostatic chuck; and a cooling plate made of aluminum or an aluminum alloy connected below the heating plate, wherein a surface of the heating plate corresponding to the cooling plate is defined as a first surface and a surface of the cooling plate corresponding to the heating plate is defined as a second surface, a gap space is provided between the heating plate and the cooling plate, the gap space extending in a direction along the first surface and the second surface, and an anodized coating is provided on at least one or both of the first surface exposed in the gap space and the second surface exposed in the gap space. Effect of the Invention

[0006] According to one aspect, the present disclosure can provide a substrate mounting table, a substrate processing apparatus, and a substrate processing method that can be used in high-temperature processes. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a vertical cross-sectional view showing an example of a plasma processing apparatus. [Diagram 2] 2 is a schematic cross-sectional view of an example of the substrate mounting table according to the first embodiment. [Diagram 3] FIG. 2 is an example of a partially enlarged schematic cross-sectional view of the substrate mounting table according to the first embodiment. [Figure 4] 1 is an example of a table showing the relationship between anodizing and emissivity. [Diagram 5] 1 is a schematic cross-sectional view of a substrate mounting table according to a reference example. [Figure 6] FIG. 11 is a schematic cross-sectional view of a substrate mounting table according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and duplicated descriptions may be omitted.

[0009] [Plasma processing equipment] A plasma processing apparatus 100 (substrate processing apparatus) will be described with reference to Fig. 1. Fig. 1 is a vertical cross-sectional view showing an example of the plasma processing apparatus 100.

[0010] The plasma processing apparatus 100 shown in FIG. 1 is an inductively coupled plasma (ICP) processing apparatus that performs various substrate processing methods on a rectangular substrate G (hereinafter simply referred to as a substrate) for a flat panel display (hereinafter referred to as an FPD) in plan view. The substrate is mainly made of glass, and transparent synthetic resin may be used depending on the application. The substrate processing includes a film formation process using a chemical vapor deposition (CVD) method, an etching process, and the like. Examples of FPDs include a liquid crystal display (LCD), an electroluminescence (EL), and a plasma display panel (PDP). The substrate includes a form in which a circuit is patterned on its surface, as well as a support substrate. The planar dimensions of FPD substrates are becoming larger with each generation, and the planar dimensions of the substrate G processed by the plasma processing apparatus 100 include at least dimensions ranging from about 1500 mm×1800 mm for the sixth generation to about 3000 mm×3400 mm for the 10.5th generation. The thickness of the substrate G is about 0.2 mm to several mm.

[0011] 1 includes a processing vessel 20 having a rectangular box shape, a substrate mounting stage (mounting stage) 70 having a rectangular outer shape in a plan view that is disposed in the processing vessel 20 and on which a substrate G is mounted, and a control unit 90. The processing vessel may have a shape such as a cylindrical box or an elliptical cylindrical box, and in this embodiment, the substrate mounting stage is also circular or elliptical, and the substrate mounted on the substrate mounting stage is also circular or the like.

[0012] Processing vessel 20 is divided into two spaces, upper and lower, by metal window 30, with antenna chamber A, which is the upper space, being formed by upper chamber 13, and processing chamber S, which is the lower space, being formed by lower chamber 17. In processing vessel 20, a rectangular ring-shaped support frame 14 is disposed at the boundary between upper chamber 13 and lower chamber 17 so as to protrude into the inside of processing vessel 20, and metal window 30 is attached to support frame 14.

[0013] An upper chamber 13 forming the antenna room A is formed by a side wall 11 and a top plate 12, and is formed as a whole from a metal such as aluminum or an aluminum alloy.

[0014] The lower chamber 17 having the processing space S therein is formed by a side wall 15 and a bottom plate 16, and is made of a metal such as aluminum or an aluminum alloy as a whole. The side wall 15 is grounded by a ground wire 21.

[0015] The support frame 14 is formed from a metal such as conductive aluminum or an aluminum alloy, and can also be called a metal frame.

[0016] A rectangular annular (endless) seal groove 22 is formed at the upper end of the side wall 15 of the lower chamber 17, and a seal member 23 such as an O-ring is fitted into the seal groove 22. The seal member 23 is held by the abutting surface of the support frame 14, thereby forming a seal structure between the lower chamber 17 and the support frame 14.

[0017] A loading / unloading port 15a for loading / unloading a substrate G into / from the lower chamber 17 is provided in the side wall 15 of the lower chamber 17, and the loading / unloading port 15a is configured to be freely opened and closed by a gate valve 24. A transfer chamber (neither shown) containing a transfer mechanism is adjacent to the lower chamber 17, and the gate valve 24 is controlled to open and close, and the substrate G is loaded and unloaded by the transfer mechanism through the loading / unloading port 15a.

[0018] In addition, a plurality of exhaust ports 16a are provided in the bottom plate 16 of the lower chamber 17. In the lower chamber 17, the side wall 15 of the processing vessel 20 that houses the substrate mounting table 70 is formed in a rectangular cylindrical shape. In other words, the processing vessel 20 is formed in a rectangular horizontal cross section at least at the position of the lower chamber 17 that houses the substrate mounting table 70. In addition, the substrate mounting table 70 is formed in a rectangular shape when viewed from above in a plan view. In other words, the substrate mounting table 70 is formed in a rectangular horizontal cross section. A plurality of exhaust ports 16a are arranged around the substrate mounting table 70 in the bottom plate 16 of the processing vessel 20. In other words, the exhaust ports 16a are arranged outside the substrate mounting table 70 and inside the side wall 15 of the processing vessel 20 (lower chamber 17) when viewed in a plan view.

[0019] Each exhaust port 16a is connected to an exhaust device 300. A pressure gauge (not shown) is provided at an appropriate position in the lower chamber 17, and monitor information from the pressure gauge is transmitted to the control unit 90.

[0020] The substrate mounting table 70 has an electrostatic chuck 71, a heating plate 72, and a cooling plate 73. The electrostatic chuck 71 has a mounting surface for holding a substrate G on its upper surface, and includes a base material 711, a dielectric layer 712, and an adsorption electrode 713.

[0021] The base material 711 has a rectangular shape in a plan view, and has planar dimensions approximately equal to those of the substrate G mounted on the substrate mounting table 70. The length of the long side of the base material 711 can be set to approximately 1800 mm to 3400 mm, and the length of the short side can be set to approximately 1500 mm to 3000 mm. With respect to these planar dimensions, the thickness of the base material 711 can be, for example, approximately 50 mm to 100 mm.

[0022] The heating plate 72 is disposed below the substrate 711 of the electrostatic chuck 71. The cooling plate 73 is disposed below the heating plate 72.

[0023] A box-shaped pedestal 78 made of an insulating material and having a step on its inside is fixed on the bottom plate 16 of the lower chamber 17, and the substrate mounting table 70 is placed on the step of the pedestal 78.

[0024] The upper surface 711a of the substrate 711 is provided with a dielectric layer 712 (e.g., a ceramic spray coating) which is a dielectric coating formed by spraying a ceramic such as alumina or yttria, and an attraction electrode 713 (conductive layer) which is embedded inside the dielectric layer 712, has an electrostatic attraction function, and is made of tungsten, molybdenum, or the like.

[0025] The chucking electrode 713 is connected to a DC power supply 85 via a power supply line 84. When a switch (not shown) on the power supply line 84 is turned on by the control unit 90, a DC voltage is applied from the DC power supply 85 to the chucking electrode 713, generating a Coulomb force. Due to this Coulomb force, the substrate G is electrostatically attracted to the upper surface of the electrostatic chuck 71 and held in a state placed on the substrate upper surface 711a via the dielectric layer 712. The substrate upper surface 711a on the upper surface of the substrate 711 is a mounting surface on which the electrostatic chuck 71 places the substrate G, and is also a mounting surface on which the substrate placement table 70 places the substrate G.

[0026] A heat medium flow path 73a that winds to cover the entire area of ​​a rectangular plane is provided on the cooling plate 73 that constitutes the substrate mounting table 70. Both ends of the heat medium flow path 73a are connected to a feed pipe 73b through which the heat medium is supplied to the heat medium flow path 73a and a return pipe 73c through which the heat medium that has been heated by flowing through the heat medium flow path 73a is discharged.

[0027] 1, a feed flow path 87 and a return flow path 88 are connected to the feed pipe 73b and the return pipe 73c, respectively, and the feed flow path 87 and the return flow path 88 are connected to a chiller 86. The chiller 86 has a main body that controls the temperature and discharge flow rate of the heat medium, and a pump that pressure-feeds the heat medium (neither is shown). A refrigerant is used as the heat medium, and Galden (registered trademark), Fluorinert (registered trademark), or the like is used as this refrigerant.

[0028] Further, a heating element 72a (see FIG. 2 described later) is provided on the heating plate 72. The heating element 72a is, for example, a resistor heater, and may be made of tungsten or molybdenum, or a compound of any one of these metals with alumina, titanium, or the like.

[0029] A temperature sensor (not shown) such as a thermocouple is disposed on the base material 711, and monitor information from the temperature sensor is transmitted to the control unit 90 as needed. Then, based on the transmitted monitor information, the control unit 90 performs temperature control of the base material 711 and the substrate G. More specifically, the control unit 90 adjusts the power supplied to the heating element 72a and the temperature and flow rate of the heat medium supplied from the chiller 86 to the feed flow path 87. Then, the amount of heat generated by the heating element 72a is adjusted, and the heat medium whose temperature and flow rate have been adjusted is circulated through the heat medium flow path 73a, thereby performing temperature control of the substrate mounting table 70.

[0030] A step is formed by the outer periphery of electrostatic chuck 71 and the upper surface of pedestal 78, and a rectangular frame-shaped focus ring 79 is placed on this step. With focus ring 79 placed on the step, the upper surface of focus ring 79 is set to be slightly lower than the upper surface of electrostatic chuck 71. Focus ring 79 is made of ceramics such as alumina or quartz. Note that the upper surface of electrostatic chuck 71 is made slightly smaller than substrate G, so that the peripheral portion of substrate G slightly protrudes from the peripheral portion of electrostatic chuck 71 and comes into contact with the inner edge of focus ring 79, and is separated from the upper surface of focus ring 79 to form a small gap.

[0031] A power supply member 80 is connected to the lower surface of the heating plate 72 through an opening penetrating from the lower surface to the upper surface of the cooling plate 73. The base material 711 of the electrostatic chuck 71, the heating plate 72, and the cooling plate 73 are provided so as to be electrically conductive. A power supply line 81 is connected to the lower end of the power supply member 80, and the power supply line 81 is connected to a high frequency power supply 83, which is a bias power supply, via a matcher 82 that performs impedance matching. When high frequency power, for example, 3.2 MHz, is applied from the high frequency power supply 83 to the substrate mounting table 70, an RF bias is generated, and ions generated by the high frequency power supply 56, which is a source source for plasma generation described below, are attracted to the substrate G, so that, for example, a film formation process can be performed on the substrate G. In this way, the substrate mounting table 70 forms a bias electrode on which the substrate G is mounted and which generates an RF bias. At this time, a portion of the lower chamber 17 that is at ground potential functions as an opposing electrode of the bias electrode, and constitutes a return circuit for the high frequency power. The metal window 30 may be configured as a part of the return circuit for the high frequency power. The metal window 30 is formed by a plurality of divided metal windows 31. The number of divided metal windows 31 forming the metal window 30 can be set to various numbers, such as 12 or 24.

[0032] The divided metal window 31 has a conductor plate 32 and a shower plate 34. The divided metal window 31 also serves as a process gas discharge section for discharging a process gas into the inside of the process chamber S. Both the conductor plate 32 and the shower plate 34 are made of aluminum, an aluminum alloy, stainless steel, or the like, which is a non-magnetic, conductive, and corrosion-resistant metal or a metal that has been subjected to a corrosion-resistant surface treatment. The corrosion-resistant surface treatment is, for example, anodizing treatment or ceramic spraying. In addition, an exposed surface 34a of the shower plate 34 facing the process chamber S may be subjected to a plasma-resistant coating by anodizing treatment or ceramic spraying.

[0033] Each divided metal window 31 constituting the metal window 30 is suspended from the top plate 12 of the upper chamber 13 by a plurality of suspenders (not shown). A spacer (not shown) made of an insulating material is disposed above each divided metal window 31, and a high-frequency antenna (inductively coupled antenna) 51 is disposed at a distance from the conductor plate 32 by the spacer. The high-frequency antenna 51 contributes to plasma generation and is formed by winding an antenna wire made of a metal with good electrical conductivity such as copper in a circular or spiral shape. For example, multiple circular antenna wires may be disposed. The high-frequency antenna 51 is disposed on the upper surface of the divided metal window 31, and is therefore suspended from the top plate 12 via the divided metal window 31. The high-frequency antenna 51 is disposed in the antenna chamber A of the upper chamber 13 at the top of the processing vessel 20.

[0034] A gas diffusion groove 33 is formed on the lower surface of the conductor plate 32, and a through hole 32b is provided to connect the gas diffusion groove 33 to the upper surface 32a of the conductor plate. At least a part of the gas introduction pipe 52 is embedded in the through hole 32b. A plurality of gas discharge holes 35 are provided in the shower plate 34, which communicate with the gas diffusion groove 33 of the conductor plate 32 and the processing chamber S. The shower plate 34 is fastened to the lower surface of the conductor plate 32 in the region outside the gas diffusion groove 33 by metal screws (not shown). The gas diffusion groove may be provided on the upper surface of the shower plate. The shape of the recess constituting the gas diffusion groove 33 is not limited to a so-called elongated shape, and may be a recess spreading in a planar shape. The shape of the recess is not limited as long as a space for diffusing gas is formed.

[0035] Each divided metal window 31 is electrically insulated from the support frame 14 and the adjacent divided metal window 31 by an insulating member 37. Here, the insulating member 37 is made of a fluororesin such as PTFE (Polytetrafluoroethylene). An end face 37a of the insulating member 37 facing the processing chamber S is flush with an exposed face 34a of the shower plate 34 facing the processing chamber S, and an insulating cover member 38 is disposed straddling the exposed face 34a of the adjacent shower plate 34 while covering the end face 37a of the insulating member 37. This cover member 38 is made of ceramics such as alumina.

[0036] The insulating member 37 is made of a resin such as PTFE, which has high insulating performance and is lightweight. However, the plasma resistance of resin is not as high as that of ceramics such as alumina. Furthermore, it is difficult to perform plasma-resistant coating on the surface of the resin by anodizing or ceramic spraying. Therefore, in the plasma processing apparatus 100, the end surface 37a of the insulating member 37 on the processing chamber S side is covered with a cover member 38 made of ceramics, for example, to protect the insulating member 37 from plasma. Each insulating member 37, which insulates the support frame 14 and the divided metal window 31, and the adjacent divided metal windows 31 from each other, is covered with the cover member 38.

[0037] A power supply member 53 extending above the upper chamber 13 is connected to the high-frequency antenna 51, and a power supply line 54 is connected to the upper end of the power supply member 53. The power supply line 54 is connected to a high-frequency power source 56 via a matching box 55 that performs impedance matching.

[0038] When a high frequency power of, for example, 13.56 MHz is applied to the high frequency antenna 51 from the high frequency power supply 56, an inductive electric field is formed in the lower chamber 17. Due to this inductive electric field, the processing gas supplied from the shower plate 34 to the processing chamber S is converted into plasma, generating inductively coupled plasma.

[0039] The high frequency power supply 56 is a source for generating plasma, and the high frequency power supply 83 connected to the substrate mounting table 70 is a bias source for attracting the generated ions. In this way, by using two high frequency power supplies to generate plasma and control ion energy, plasma generation and ion energy control are performed independently, thereby increasing the flexibility of the process.

[0040] 1, the gas introduction pipes 52 of each divided metal window 31 are gathered together in one place inside the antenna chamber A, and the gas introduction pipes 52 extending upward penetrate a supply port 12a opened in the top plate 12 of the upper chamber 13. The gas introduction pipes 52 are connected to a process gas supply source 64 via a gas supply pipe 61 that is airtightly connected.

[0041] An opening / closing valve 62 and a flow rate controller 63 such as a mass flow controller are provided in the gas supply pipe 61. A processing gas supply unit 60 is formed by the gas supply pipe 61, the opening / closing valve 62, the flow rate controller 63, and a processing gas supply source 64. The gas supply pipe 61 branches in the middle, and each branch pipe is connected to an opening / closing valve, a flow rate controller, and a processing gas supply source appropriate for the type of processing gas (not shown).

[0042] In plasma processing, a processing gas is supplied from a processing gas supply unit 60 through a gas supply pipe 61 and a gas introduction pipe 52 to the gas diffusion grooves 33 of the conductor plate 32 of each divided metal window 31. Then, the processing gas is discharged from each gas diffusion groove 33 through the gas discharge holes 35 of each shower plate 34 into the processing chamber S.

[0043] Thus, the plasma processing apparatus 100 includes a plasma generating unit that generates processing plasma for performing substrate processing (film formation processing, etching processing, etc.) on the substrate G. The plasma generating unit includes at least the metal window 30 and the high-frequency antenna 51. The high-frequency power supply 56 supplies high-frequency power to the high-frequency antenna 51, and the processing gas supply unit 60 supplies processing gas to the processing chamber S through the divided metal window 31 (processing gas discharge unit). The plasma generating unit forms an induction electric field in the processing chamber S, and generates plasma of the processing gas supplied into the processing chamber S by this induction electric field.

[0044] The control unit 90 controls the operation of each component of the plasma processing apparatus 100, such as the chiller 86, the high frequency power supplies 56 and 83, the processing gas supply unit 60, and the exhaust unit 300 based on monitor information transmitted from a pressure gauge. The control unit 90 has a central processing unit (CPU), a read only memory (ROM), and a random access memory (RAM). The CPU executes a predetermined process according to a recipe (process recipe) stored in a storage area of ​​the RAM or ROM. The recipe sets control information for the plasma processing apparatus 100 with respect to process conditions. The control information includes, for example, the gas flow rate, the pressure in the processing vessel 20, the temperature in the processing vessel 20, the temperature of the substrate 711, and the process time.

[0045] The recipe and the program applied by the control unit 90 may be stored in, for example, a hard disk, a compact disk, a magneto-optical disk, etc. The recipe and the like may be stored in a portable computer-readable storage medium such as a CD-ROM, a DVD, a memory card, etc., and set in the control unit 90 and read out. The control unit 90 also has user interfaces such as input devices such as a keyboard and a mouse for inputting commands, a display device such as a display for visualizing and displaying the operating status of the plasma processing apparatus 100, and an output device such as a printer.

[0046] Here, the substrate mounting table 70 will be further described with reference to Figures 2 and 3. Figure 2 is an example of a schematic cross-sectional view of the substrate mounting table 70 according to the first embodiment.

[0047] The substrate mounting table 70 includes an electrostatic chuck 71 , a heating plate 72 , and a cooling plate 73 .

[0048] The electrostatic chuck 71 has a mounting surface on the upper surface thereof for holding a substrate G, and includes a base material 711, a dielectric layer 712, and an adsorption electrode 713 (see FIG. 1; not shown in FIG. 2). The dielectric layer 712 is formed on the upper surface of the base material 711, and the adsorption electrode 713 is provided inside the dielectric layer 712. The dielectric layer 712 mounts and holds the substrate G on its upper surface.

[0049] The substrate 711 is conductive, and high-frequency power is applied from the power supply member 80 (see FIG. 1) via the heating plate 72. The substrate 711 is preferably made of a material that has a small thermal expansion difference with the dielectric layer 712 at a process temperature (e.g., 250° C.). The substrate 711 is made of, for example, stainless steel. This reduces the thermal expansion difference between the substrate 711 and the dielectric layer 712, and prevents the dielectric layer 712 from peeling off from the substrate 711 due to the thermal expansion difference between the substrate 711 and the dielectric layer 712 in a high-temperature process (e.g., 250° C.). In other words, the generation of contaminants such as particles due to fragments of the peeled dielectric layer 712, insulation breakdown, and abnormal discharge are prevented. The surface of the substrate 711 made of stainless steel is preferably covered with a Ni plating layer 714 to prevent the substrate 711 from being corroded by plasma, process gas, and the like.

[0050] The heating plate 72 is preferably made of a material having electrical conductivity and good thermal conductivity. The heating plate 72 is made of, for example, aluminum or an aluminum alloy. The heating plate 72 has a heating element 72a therein. The heating element 72a generates heat when power is supplied from an external power source (not shown), and heats the heating plate 72. The upper surface of the heating plate 72 abuts against the lower surface of the base material 711, and the heating element 72a generates heat, which is transferred from the heating plate 72 to the electrostatic chuck 71, thereby heating the substrate G placed on the electrostatic chuck 71. When heat from the plasma generated in the processing chamber S enters the substrate G, the heat is transferred to the heating plate 72 via the electrostatic chuck 71.

[0051] The cooling plate 73 is preferably made of a material that is electrically conductive and has good thermal conductivity. The cooling plate 73 is made of, for example, aluminum or an aluminum alloy. The cooling plate 73 also has a heat medium flow path 73a inside. The heat medium adjusted to a predetermined temperature (for example, 100°C) by a chiller 86 (see FIG. 1) is supplied to the heat medium flow path 73a via a feed pipe 73b. The heat medium discharged from the heat medium flow path 73a circulates to the chiller 86 (see FIG. 1) via a return pipe 73c.

[0052] FIG. 3 is an example of a partially enlarged schematic cross-sectional view of the substrate mounting table 70 according to the first embodiment.

[0053] Here, a support member 74 is disposed between the heating plate 72 and the cooling plate 73. The heating plate 72 is supported by the cooling plate 73 via the support member 74. The support member 74 may be disposed, for example, by forming a recess on the upper surface of the cooling plate 73. The support member 74 is preferably made of a material that is conductive and has lower thermal conductivity than the heating plate 72 and the cooling plate 73. The support member 74 is, for example, made of stainless steel. The support members 74 are provided in a plurality of positions on the outer periphery side of the heating plate 72 and the cooling plate 73, either continuously or spaced apart in the circumferential direction, so that the heating plate 72 and the cooling plate 73 do not come into direct contact with each other. On the other hand, in the portion where the heating plate 72 and the cooling plate 73 indirectly come into contact with each other via the support member 74, the amount of heat transfer is reduced because the thermal conductivity of the support member 74 is low. This suppresses heat transfer between the heating plate 72 and the cooling plate 73 via the support member 74. As a result, the amount of heat transfer between the heating plate 72 and the cooling plate 73 can be kept small, while the heating plate 72 can be reliably supported by the cooling plate 73.

[0054] A gap space 75 is formed between the cooling plate 73 and the heating plate 72. A seal member 76a (second seal member) is disposed between the cooling plate 73 and the heating plate 72 at the outer periphery surrounding the gap space 75. The inside of this gap space 75 is sealed from the processing chamber S by the seal member 76a. The cooling plate 73 and the heating plate 72 sandwich the seal member 76a, but do not come into direct contact with each other. As with the support member 74, they come into indirect contact with each other via the seal member 76a. The seal member 76a may be disposed, for example, on the outside of the support member 74.

[0055] Furthermore, the gap space 75 may be in communication with the space below the cooling plate 73 (the space surrounded by the lower surface of the cooling plate 73, the inner circumferential surface of the pedestal 78, and the upper surface of the bottom plate 16) through an opening in the cooling plate 73 through which the power supply member 80 (see FIG. 1) is inserted. Furthermore, a seal member (not shown) may be disposed between the gap space 75 and the space below the cooling plate 73, so that the gap space 75 is sealed.

[0056] 3, the surface of the heating plate 72 that faces the cooling plate 73 is defined as a first surface S1. The surface of the cooling plate 73 that faces the heating plate 72 is defined as a second surface S2. Between the cooling plate 73 and the heating plate 72, there is a gap space 75 that extends in a direction along the first surface S1 and the second surface S2. The distance between the first surface S1 and the second surface S2 is 2 mm or more and 10 mm or less.

[0057] 3, a case is described in which a recess is formed on the upper surface (second surface S2) of the cooling plate 73 to form the gap space 75 between the cooling plate 73 and the heating plate 72, but the present invention is not limited to this. A recess may be formed on the lower surface (first surface S1) of the heating plate 72 to form the gap space 75 between the cooling plate 73 and the heating plate 72. Alternatively, a recess may be formed on both the upper surface (first surface S1) of the cooling plate 73 and the lower surface (second surface S2) of the heating plate 72 to form the gap space 75 between the cooling plate 73 and the heating plate 72.

[0058] The heating plate 72 is anodized on a first surface S1 exposed to the gap space 75, and has an anodized aluminum coating 721. In other words, the heating plate 72 has the anodized aluminum coating 721 at least on the wall surface exposed to the gap space 75. Note that, as shown in Figs. 2 and 3, the heating plate 72 may have the anodized aluminum coating 721 on the entire surface.

[0059] The cooling plate 73 is anodized on the second surface S2 exposed to the gap space 75, and has an anodized aluminum coating 731. In other words, the cooling plate 73 has the anodized aluminum coating 731 at least on the wall surface exposed to the gap space 75. Note that, as shown in Figs. 2 and 3, the cooling plate 73 may have the anodized aluminum coating 731 on the entire surface.

[0060] In addition, the substrate mounting table 70 will be described taking as an example a case where an alumite film is provided on both the first surface S1 of the heating plate 72 and the second surface S2 of the cooling plate 73, but is not limited to this. The substrate mounting table 70 may be configured such that an alumite film is provided on at least one of the first surface S1 of the cooling plate 73 and the second surface S2 of the heating plate 72.

[0061] The cooling plate 73 is supported by a pedestal 78. A seal member 76b is disposed between the cooling plate 73 and the pedestal 78. Furthermore, a seal member 76c is disposed between the pedestal 78 and the bottom plate 16. The space below the cooling plate 73 is sealed from the processing chamber S by the seal members 76b and 76c. The space below the cooling plate 73 may be in communication with the outside of the processing vessel 20 and may be filled with the air.

[0062] Furthermore, the supply pipe 73b and the return pipe 73c through which the heat medium flows are provided with seal members 77 (first seal members) at various connections. That is, the seal members 77 prevent the heat medium from leaking to the outside, and come into contact with the heat medium and are cooled to a temperature approximately equal to that of the heat medium.

[0063] The gap space 75 may be in a vacuum atmosphere. Alternatively, the gap space 75 may be in an air atmosphere. Alternatively, the gap space 75 may be filled with a heat transfer gas (for example, He gas).

[0064] Here, an example of processing of the substrate G by the plasma processing apparatus 100 will be described.

[0065] First, the substrate G is placed on the substrate placement table 70 and electrostatically attracted by the electrostatic chuck 71 .

[0066] Next, a step of heating the electrostatic chuck 71 by the heating plate 72 is performed. Here, the control unit 90 controls a power source (not shown) that supplies power to the heating element 72a based on a detected temperature of a temperature sensor (not shown) such as a thermocouple provided on the base material 711. As a result, the temperatures of the heating plate 72, the electrostatic chuck 71 including the base material 711, and the substrate G placed on the electrostatic chuck 71 are adjusted to desired temperatures (e.g., 250°C). Meanwhile, a heat medium at a temperature lower than the desired temperature (e.g., 100°C) flows through the heat medium flow passage 73a of the cooling plate 73, and the temperature of the cooling plate 73 is also low (e.g., 100°C).

[0067] Next, a process of removing heat from the electrostatic chuck 71 by the cooling plate 73 through heat exchange via the gap space 75 is performed. Here, the control unit 90 controls the plasma processing apparatus 100 to perform a film-forming plasma process on the substrate G. When performing the plasma process on the substrate G, plasma is generated in the process chamber S, and heat from the plasma is input to the substrate G and the substrate mounting table 70. The heat from the plasma is transferred to the heating plate 72 via the substrate G and the electrostatic chuck 71. Meanwhile, the heating plate 72 itself also generates heat by the heating element 72a. The heat input from the plasma and the heat generated by the heating plate 72 are thermally radiated from the first surface S1 of the heating plate 72 to the gap space 75. Then, the radiated heat radiated from the heating plate 72 to the gap space 75 is thermally absorbed by the second surface S2 of the cooling plate 73. At this time, the anodized aluminum coating covering the first surface S1 and the second surface S2 has high thermal emissivity and absorptivity, as described later. That is, by forming the anodized aluminum film 721 on the first surface S1, heat is efficiently dissipated, and by forming the anodized aluminum film 731 on the second surface S2, heat is efficiently absorbed. Therefore, in the gap space 75, heat is efficiently transferred from the first surface S1 to the second surface S2 by thermal radiation. Then, in the cooling plate 73, the heat is dissipated to the heat medium flowing through the heat medium flow path 73a. In this way, the substrate G and the electrostatic chuck 71 are heat-extracted by the cooling plate 73 through heat exchange via the gap space 75.

[0068] At the same time, a process of adjusting the temperature of the substrate G is performed via the electrostatic chuck 71. Here, the control unit 90 controls a power source (not shown) that supplies power to the heating element 72a based on a temperature detected by a temperature sensor (not shown) such as a thermocouple provided on the base material 711.

[0069] By these steps, the temperature of the substrate G during the substrate processing is controlled to a desired temperature.

[0070] 2 and 3, the substrate G can be processed in a high-temperature process (for example, 250° C.). In addition, when plasma heat is input to the substrate G or the substrate mounting table 70, the heat can be dissipated to a heat medium.

[0071] Furthermore, the temperature of the heat medium flowing through the feed pipe 73b and the return pipe 73c can be set to a temperature (e.g., 100°C) lower than the temperature (e.g., 250°C) of the high-temperature process of the substrate G. This makes it possible to prevent the seal members 77 provided in the feed pipe 73b and the return pipe 73c from being deteriorated by heat.

[0072] Here, the thermal radiation and thermal absorption by the anodized aluminum coating will be explained with reference to Fig. 4. Fig. 4 is an example of a table showing the relationship between various anodized aluminum treatments and emissivity.

[0073] In the table of FIG. 4, in Nos. 1 to 15, various types of anodizing treatments were performed on aluminum alloy (A5052) substrates. Some of the anodizing treatments in Nos. 1 to 15 are treatments in which anodizing is performed by different methods. No. 16, which is the first comparative example, shows an untreated (before anodizing) aluminum alloy (A5052) substrate. In Nos. 17 to 19, which are the second to fourth comparative examples, the aluminum alloy (A5052) substrate shown in No. 16 was subjected to a blasting treatment to change the surface roughness (substrate surface finish). For Nos. 1 to 19, the substrate surface finish (arithmetic mean roughness Ra), treatment, thickness of the anodizing film, substrate temperature at the time of emissivity measurement, and emissivity are shown, respectively.

[0074] As shown in Figure 4, the emissivity of the untreated substrate shown in No. 16 is 0.38. In contrast, the various anodized coatings and film thicknesses shown in Nos. 1 to 15 have high emissivity values ​​close to 1. In other words, by providing an anodized coating on the surface of the substrate, the emissivity is improved.

[0075] Here, in the various anodizing treatments shown in No. 1 to 15, the substrate surface finish (arithmetic mean roughness Ra) is greater than that of the untreated state shown in No. 16. In other words, the surface area is increased. For this reason, in No. 17 to 19, the substrate surface area is increased by blasting.

[0076] No increase in emissivity was observed in the various blast treatments shown in Nos. 17 to 19.

[0077] In this way, regardless of the method of anodizing, providing an anodized aluminum coating on the surface of the base material improves the emissivity. That is, providing an anodized aluminum coating 721 on the surface of the heating plate 72 can increase the amount of radiated heat from the heating plate 72 to the gap 75. Generally, the higher the thermal emissivity, the higher the thermal absorption rate, so an increase in thermal radiation also indicates an increase in heat absorption. Therefore, the absorption of radiated heat from the gap 75 to the cooling plate 73 can also be increased.

[0078] This allows the heat of the plasma to be suitably transferred from the heating plate 72 to the cooling plate 73 via the gap space 75 .

[0079] Here, a substrate mounting table 70C according to a reference example will be described. Fig. 5 is an example of a schematic cross-sectional view of the substrate mounting table 70C according to the reference example.

[0080] In the substrate mounting table 70C according to the reference example, the heating plate 72 is not provided, and a cooling plate 73 is provided directly below the base material 711.

[0081] Here, an example will be described in which the substrate G is processed in a high-temperature process (e.g., 250° C.) on the substrate mounting table 70C according to the reference example. A high-temperature heat medium (e.g., 250° C.) is circulated through the heat medium flow path 73a of the cooling plate 73. Therefore, the seal member 77 and the seal member 76b are also exposed to high temperatures. This may cause the seal member 77 and the seal member 76b to deteriorate due to heat, resulting in an increased frequency of replacement.

[0082] 2 and 3, even when the substrate G is processed in a high-temperature process (e.g., 250° C.), a heat medium at a temperature lower than the desired process temperature (e.g., 100° C.) flows through the heat medium passage 73a of the cooling plate 73, so that the cooling plate 73 can be maintained at a low temperature. This makes it possible to prevent the seal members 77 and 76b from being deteriorated by heat.

[0083] FIG. 6 is an example of a schematic cross-sectional view of a substrate mounting table 70A according to the second embodiment.

[0084] As shown in Fig. 6, the substrate mounting table 70A includes a gas passage 89a communicating with the gap space 75, on-off valves 89b1 and 89b2 provided in the gas passage 89a, a pressure sensor 89c provided in the gas passage 89a for detecting the pressure of the gap space 75, a gas supply source 89d1, and an exhaust device 89d2. Although not shown in Fig. 6, a seal member (not shown) is arranged around the opening (see Fig. 1) of the cooling plate 73 through which the power supply member 80 is inserted, and seals the gap space 75 and the space below the cooling plate 73. As a result, the gap space 75 is formed such that the upper surface is defined by the first surface S1, the lower surface is defined by the second surface S2, the outer circumferential side is defined by the seal member 76a, and the inner circumferential side is defined by the seal member (not shown).

[0085] By opening the on-off valve 89b1, gas is filled from the gas supply source 89d1 through the gas passage 89a into the gap space 75. The gas filled into the gap space 75 may be the atmosphere or a heat transfer gas (e.g., He gas, Ar gas, etc.). In addition, by opening the on-off valve 89b2, the gas in the gap space 75 is exhausted by the exhaust device 89d2 through the gas passage 89a.

[0086] In this way, the substrate mounting table 70A can control the pressure (filling amount) of the gas in the gap space 75. Also, the pressure (filling amount) of the heat transfer gas in the gap space 75 can be controlled. This makes it possible to control heat transfer by thermal convection via the heat transfer gas. That is, in addition to heat transfer by radiation, the amount of heat transfer from the heating plate 72 to the cooling plate 73 by the heat transfer gas can be controlled.

[0087] Here, an example of processing of the substrate G by the plasma processing apparatus 100 including the substrate mounting table 70A according to the second embodiment will be described.

[0088] First, a step of filling the gap space 75 with air or a heat transfer gas is performed. That is, the heat transfer characteristics between the heating plate 72 and the cooling plate 73 are adjusted. This makes it possible to adjust the heat transfer characteristics between the heating plate 72 and the cooling plate 73 according to, for example, the substrate processing process. Also, in a substrate processing system including a plurality of plasma processing apparatuses 100, the individual differences in the heat transfer characteristics between the heating plate 72 and the cooling plate 73 can be adjusted.

[0089] Although the plasma processing apparatus 100 has been described above, the present disclosure is not limited to the above-mentioned embodiment, etc., and various modifications and improvements are possible within the scope of the gist of the present disclosure described in the claims. In addition, although a case where a film formation process is performed as the substrate processing has been described, the present invention is not limited to this, and can also be applied to etching processes, ashing processes, etc., in which the substrate mounting table becomes hot. [Explanation of symbols]

[0090] G board 20 Processing vessel 70 Board mounting table 71 Electrostatic Chuck 711 Base material 711a Top surface of base material 712 Dielectric layer 713 Adsorption electrode 714 Ni plating layer 72 Heating Plate 72a Heating element 721 Anodized coating 73 Cooling Plate 73a Heat transfer medium flow path 73b Feed pipe 73c Return pipe 731 Anodized coating 74 Support member 75 Interstitial Space 76a to 76c, 77 Sealing members 78 Pedestal 79 Focus Ring 89a Gas passage 89b1 On-off valve 89b2 On-off valve 89c Pressure Sensor 89d1 Gas supply source 89d2 Exhaust system S1 First Side S2 Second Side 90 Control section 100 Plasma treatment device

Claims

1. A substrate mounting table is installed in a processing chamber for processing a substrate, the substrate being mounted on the substrate mounting table, the substrate mounting table comprising: The substrate mounting table is an electrostatic chuck including a base material having a dielectric layer with an adsorption electrode built in on a mounting surface on which the substrate is mounted; a heating plate made of aluminum or an aluminum alloy and connected below the electrostatic chuck; a cooling plate made of aluminum or an aluminum alloy and connected below the heating plate; a surface of the heating plate corresponding to the cooling plate is defined as a first surface; a surface of the cooling plate corresponding to the heating plate is a second surface; a gap space extending in a direction along the first surface and the second surface is provided between the heating plate and the cooling plate, At least one or both of the first surface exposed to the gap space and the second surface exposed to the gap space have an anodized aluminum coating. Board mounting table.

2. In the gap space, the distance between the first surface and the second surface is 2 mm or more and 10 mm or less. The substrate mounting table according to claim 1 .

3. the heating plate having a heating element; The cooling plate has a heat medium flow path through which a heat medium flows. The substrate mounting table according to claim 1 .

4. A first seal member is disposed in a feed pipe and a return pipe connected to the heat medium flow path. The substrate mounting table according to claim 3 .

5. The heating plate is supported on the cooling plate via a support member. The substrate mounting table according to claim 1 .

6. A second seal member is disposed between the heating plate and the cooling plate surrounding the gap space. The substrate mounting table according to claim 1 .

7. The gap space is filled with air or a heat transfer gas. The substrate mounting table according to claim 6 .

8. A substrate processing apparatus for processing a substrate, a processing vessel in which the substrate is processed; a substrate placement stage disposed inside the processing chamber and configured to place the substrate thereon; The substrate mounting table is an electrostatic chuck including a base material having a dielectric layer with an adsorption electrode built in on a mounting surface on which the substrate is mounted; a heating plate made of aluminum or an aluminum alloy connected below the electrostatic chuck; a cooling plate made of aluminum or an aluminum alloy and connected below the heating plate; a surface of the heating plate corresponding to the cooling plate is defined as a first surface; a surface of the cooling plate corresponding to the heating plate is a second surface; a gap space extending in a direction along the first surface and the second surface is provided between the heating plate and the cooling plate, At least one or both of the first surface exposed to the gap space and the second surface exposed to the gap space have an anodized aluminum coating. Substrate processing equipment.

9. the heating plate having a heating element; The cooling plate has a heat medium flow path through which a heat medium flows, A first seal member is disposed in a feed pipe and a return pipe connected to the heat medium flow path. The substrate processing apparatus according to claim 8 .

10. 1. A substrate processing method for processing a substrate inside a processing vessel, comprising: a substrate placement stage for placing the substrate inside the processing vessel; The substrate mounting table is an electrostatic chuck including a base material having a dielectric layer with an adsorption electrode built in on a mounting surface on which the substrate is mounted; a heating plate made of aluminum or an aluminum alloy connected below the electrostatic chuck; a cooling plate made of aluminum or an aluminum alloy and connected below the heating plate; a surface of the heating plate corresponding to the cooling plate is defined as a first surface, a surface of the cooling plate corresponding to the heating plate is defined as a second surface, a gap space is provided between the heating plate and the cooling plate, the gap space extends in a direction along the first surface and the second surface, and an alumite coating is provided on at least one or both of the first surface exposed to the gap space and the second surface exposed to the gap space; heating the electrostatic chuck with the heating plate; removing heat from the electrostatic chuck through the heating plate by the cooling plate through heat exchange via the gap space; and adjusting a temperature of the substrate via the electrostatic chuck. A method for processing a substrate.

11. Filling the gap space with air or a heat transfer gas; The method of claim 10.

12. The processing includes forming a film on the substrate. The method of claim 10.

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