KR20250015896A - Substrate mounting table, substrate processing apparatus and substrate processing method - Google Patents

Abstract

[Assignment] To provide a substrate mounting stand, a substrate processing device, and a substrate processing method that can be used in a high-temperature process.
[Solution] The present invention provides a substrate mounting stand installed inside a processing container that performs processing on a substrate, and mounting the substrate, the substrate mounting stand having an electrostatic chuck made of a base material having a dielectric layer having an adsorption electrode built into a mounting surface on which the substrate is mounted, a heating plate made of aluminum or an aluminum alloy connected to a lower side of the electrostatic chuck, and a cooling plate made of aluminum or an aluminum alloy connected to a lower side of the heating plate, the surface of the heating plate corresponding to the cooling plate being a first surface, the surface of the cooling plate corresponding to the heating plate being a second surface, and having a gap space extending in a direction along the first surface and the second surface between the heating plate and the cooling plate, and having an alumite film on at least one or both of the first surface exposed to the gap space and the second surface exposed to the gap space.

Description

{SUBSTRATE MOUNTING TABLE, SUBSTRATE PROCESSING APPARATUS AND SUBSTRATE PROCESSING METHOD}

The present disclosure relates to a substrate mounting stand, a substrate processing device, and a substrate processing method.

Patent Document 1 describes a substrate holder comprising a heat exchange jacket through which a heat medium flows, a split plate for alleviating uneven temperature distribution on a flat heat exchange surface of the heat exchange jacket, and an electrostatic chuck formed by embedding an adsorption electrode in an insulator, wherein a fluorocarbon-based heat medium heated to about 170°C is transported to the heat exchange jacket and uniformly heats the electrostatic chuck through the split plate.

Japanese Patent Publication No. 05-29300

In one aspect, the present disclosure provides a substrate mounting stand, a substrate processing apparatus, and a substrate processing method that can be used in a high temperature process.

In order to solve the above problem, according to one aspect, a substrate mounting stand is provided, which is installed inside a processing container that performs processing on a substrate, and on which the substrate is mounted, wherein the substrate mounting stand has an electrostatic chuck made of a base material having a dielectric layer having an adsorption electrode built into a mounting surface on which the substrate is mounted, a heating plate made of aluminum or an aluminum alloy connected to a lower side of the electrostatic chuck, and a cooling plate made of aluminum or an aluminum alloy connected to a lower side of the heating plate, wherein a surface of the heating plate corresponding to the cooling plate is a first surface, a surface of the cooling plate corresponding to the heating plate is a second surface, and a gap space is provided between the heating plate and the cooling plate, extending in a direction along the first surface and the second surface, and 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 alumite film.

In one aspect, the present disclosure can provide a substrate mounting stand, a substrate processing device, and a substrate processing method that can be used in a high temperature process.

Figure 1 is a cross-sectional view illustrating an example of a plasma processing device.
Fig. 2 is an example of a cross-sectional schematic diagram of a substrate mounting stand according to the first embodiment.
Fig. 3 is an example of a partially enlarged cross-sectional schematic diagram of a substrate mounting stand according to the first embodiment.
Figure 4 is an example of a table showing the relationship between alumite treatment and emissivity.
Figure 5 is an example of a cross-sectional schematic diagram of a substrate mounting stand according to a reference example.
Fig. 6 is an example of a cross-sectional schematic diagram of a substrate mounting stand according to the second embodiment.

Hereinafter, a form for implementing the present disclosure will be described with reference to the drawings. In each drawing, the same components are given the same reference numerals, and duplicate descriptions are sometimes omitted.

[Plasma treatment device]

A plasma processing device (100) (substrate processing device) will be described using Fig. 1. Fig. 1 is a cross-sectional view showing an example of a plasma processing device (100).

The plasma processing device (100) illustrated in Fig. 1 is an inductively coupled plasma (ICP) processing device that performs various substrate processing methods on a rectangular substrate (G) (hereinafter, simply referred to as a "substrate") as viewed from the plane for a flat panel display (hereinafter, "FPD"). Glass is mainly used as the substrate material, and transparent synthetic resin, etc. may be used depending on the application. Here, the substrate processing includes a film forming process using a CVD (Chemical Vapor Deposition) method, an etching process, etc. Examples of the FPD include a liquid crystal display (LCD), an electroluminescence (EL), a plasma display panel (PDP), etc. The substrate includes a support substrate in addition to a form in which a circuit is patterned on its surface. In addition, the planar dimensions of the substrate for FPD are becoming larger along with the progress of the generation, and the planar dimensions of the substrate (G) processed by the plasma processing device (100) include at least the dimensions from about 1500 mm x 1800 mm of the 6th generation to about 3000 mm x 3400 mm of the 10.5th generation, for example. In addition, the thickness of the substrate (G) is about 0.2 mm to several mm.

The plasma processing device (100) illustrated in Fig. 1 has a processing vessel (20) having a rectangular box shape, a substrate mounting table (mounting table) (70) disposed in the processing vessel (20) and having a rectangular outer shape when viewed from a plane on which a substrate (G) is mounted, and a control unit (90). In addition, the processing vessel may have a shape such as a cylindrical box shape or an oval cylindrical box shape, and in this shape, the substrate mounting table is also circular or oval, and the substrate mounted on the substrate mounting table is also circular, etc.

The processing vessel (20) is divided into two spaces, upper and lower, by a metal window (30). The upper space, the antenna room (A), is formed by the upper chamber (13), and the lower space, the processing room (S), is formed by the lower chamber (17). In the processing vessel (20), a rectangular ring-shaped support frame (14) is disposed so as to protrude from the inside of the processing vessel (20) at a position that is the boundary between the upper chamber (13) and the lower chamber (17), and a metal window (30) is mounted on the support frame (14).

The upper chamber (13) forming the antenna room (A) is formed by the side wall (11) and the top plate (12), and is formed entirely of a metal such as aluminum or an aluminum alloy.

The lower chamber (17) having the processing room (S) inside is formed by a side wall (15) and a bottom plate (16), and is formed entirely of a metal such as aluminum or an aluminum alloy. In addition, the side wall (15) is grounded by a ground wire (21).

The support frame (14) is formed of a metal such as conductive aluminum or aluminum alloy, and may also be referred to as a metal frame.

At the upper end of the side wall (15) of the lower chamber (17), a rectangular ring (uncircular shape) seal groove (22) is formed, a sealing member (23) such as an O-ring is fitted into the seal groove (22), and by holding the sealing member (23) with the contact surface of the support frame (14), a sealing structure of the lower chamber (17) and the support frame (14) is formed.

In the side wall (15) of the lower chamber (17), an inlet/outlet port (15a) for inlet/outleting a substrate (G) to/from the lower chamber (17) is provided, and the inlet/outlet port (15a) is configured to be openable by a gate valve (24). A return room (not shown) containing a return mechanism is adjacent to the lower chamber (17), and by controlling the opening/closing of the gate valve (24), the inlet/outlet of the substrate (G) is executed from the return mechanism through the inlet/outlet port (15a).

In addition, a plurality of exhaust ports (16a) are provided on the bottom plate (16) of the lower chamber (17). The side wall (15) of the processing vessel (20) that accommodates the substrate mounting stand (70) in the lower chamber (17) is formed in a cylindrical shape. In other words, the processing vessel (20) is formed in a horizontal cross-section that is rectangular at least at the position of the lower chamber (17) that accommodates the substrate mounting stand (70). In addition, the substrate mounting stand (70) is formed in a rectangular shape when viewed from above in a plan view. In other words, the substrate mounting stand (70) is formed in a horizontal cross-section that is rectangular. The exhaust ports (16a) are arranged in a plurality on the bottom plate (16) of the processing vessel (20) so as to surround the substrate mounting stand (70). In other words, the exhaust port (16a) is positioned outside the substrate mounting stand (70) when viewed from a plan view, and inside the side wall (15) of the processing vessel (20) (lower chamber (17)).

Each exhaust port (16a) is connected to an exhaust device (300). In addition, a pressure gauge (not shown) is installed at an appropriate location in the lower chamber (17), and monitor information by the pressure gauge is transmitted to the control unit (90).

The substrate mounting stand (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 (711), a dielectric layer (712), and an adsorption electrode (713).

The shape of the substrate (711) when viewed from a plan view is rectangular, and has the same planar dimensions as the substrate (G) mounted on the substrate mounting stand (70). The length of the long side of the substrate (711) can be set to about 1800 mm to 3400 mm, and the length of the short side can be set to about 1500 mm to 3000 mm. With respect to these planar dimensions, the thickness of the substrate (711) can be, for example, about 50 mm to 100 mm.

The heating plate (72) is placed under the substrate (711) of the electrostatic chuck (71). The cooling plate (73) is placed under the heating plate (72).

On the bottom plate (16) of the lower chamber (17), a box-shaped pedestal (78) formed of an insulating material and having a stepped portion on the inside is fixed, and a substrate mounting stand (70) is mounted on the stepped portion of the pedestal (78).

The upper surface of the substrate (711), which is the upper surface (711a), has a dielectric layer (712) (e.g., a ceramic sprayed film) that is a dielectric film formed by spraying ceramics such as alumina or yttria, and an adsorption electrode (713) (conductive layer) that is embedded inside the dielectric layer (712) and has an electrostatic adsorption function and is formed of tungsten, molybdenum, or the like.

The adsorption electrode (713) is connected to a DC power source (85) via a power supply line (84). When a switch (not shown) intervening in the power supply line (84) is turned on by the control unit (90), a DC voltage is applied from the DC power source (85) to the adsorption electrode (713), thereby generating a Coulomb force. By this Coulomb force, the substrate (G) is electrostatically adsorbed to the upper surface of the electrostatic chuck (71) and is held in a state of being mounted on the upper surface (711a) of the substrate (711) via the dielectric layer (712). The upper surface (711a) of the substrate (711) is a mounting surface on which the electrostatic chuck (71) mounts the substrate (G), and is also a mounting surface on which the substrate mounting base (70) mounts the substrate (G).

A winding heat medium path (73a) is provided on the cooling plate (73) constituting the substrate mounting base (70) so as to cover the entire area of the rectangular plane. At both ends of the heat medium path (73a), a transfer pipe (73b) through which heat medium is supplied to the heat medium path (73a) and a return pipe (73c) through which heat medium, whose temperature has increased by circulating the heat medium path (73a), is connected.

As shown in Fig. 1, the transfer pipe (73b) and the return pipe (73c) are respectively connected with a transfer path (87) and a return path (88), and the transfer path (87) and the return 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 supplies the heat medium (both not shown). In addition, a refrigerant is applied as the heat medium, and as the refrigerant, Galden (registered trademark) or Fluorinert (registered trademark) is applied.

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

A temperature sensor (not shown) such as a thermocouple is disposed in the substrate (711), and monitor information by the temperature sensor is transmitted to the control unit (90) from time to time. Then, based on the transmitted monitor information, temperature control of the substrate (711) and the substrate (G) is executed by the control unit (90). More specifically, the control unit (90) adjusts the power supplied to the heating element (72a), and the temperature or flow rate of the heat medium supplied from the chiller (86) to the transfer path (87). Then, the heat generation amount of the heating element (72a) is adjusted, and the heat medium for which temperature control or flow rate control is executed is circulated in the heat medium path (73a), thereby executing temperature control of the substrate mounting stand (70).

A step portion is formed by the outer periphery of the electrostatic chuck (71) and the upper surface of the pedestal (78), and a rectangular frame-shaped focus ring (79) is mounted on this step portion. With the focus ring (79) installed on the step portion, the upper surface of the focus ring (79) is set to be slightly lower than the upper surface of the electrostatic chuck (71). The focus ring (79) is formed of ceramics such as alumina or quartz. In addition, since the upper surface of the electrostatic chuck (71) is made slightly smaller than the substrate (G), the peripheral portion of the substrate (G) slightly protrudes from the peripheral portion of the electrostatic chuck (71) to reach the inner periphery of the focus ring (79), and is spaced apart from the upper surface of the focus ring (79) to form a small gap.

A power supply member (80) is connected to the lower surface of the heating plate (72) through an opening that penetrates from the lower surface to the upper surface of the cooling plate (73). In addition, the base material (711) of the electrostatic chuck (71), the heating plate (72), and the cooling plate (73) are arranged 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, through a matching device (82) that performs impedance matching. By applying high-frequency power of, for example, 3.2 MHz from the high-frequency power supply (83) to the substrate mounting stand (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 forming process can be performed on the substrate (G). In this way, the substrate mounting stand (70) mounts the substrate (G) and forms a bias electrode that generates RF bias. At this time, a portion of the inside of the lower chamber (17) that becomes the ground potential functions as the counter electrode of the bias electrode, thereby forming a return circuit of high-frequency power. In addition, the metal window (30) may be formed as a part of the return circuit of high-frequency power. The metal window (30) is formed by a plurality of segmented metal windows (31). The number of segmented metal windows (31) forming the metal window (30) can be set to various numbers, such as 12 or 24.

The split metal window (31) has a conductor plate (32) and a shower plate (34). The split metal window (31) also serves as a processing gas discharge section that discharges processing gas into the interior of the processing chamber (S). The conductor plate (32) and the shower plate (34) are both formed of a non-magnetic, conductive, and corrosion-resistant metal, or a metal that has been subjected to corrosion-resistant surface processing, such as aluminum, an aluminum alloy, or stainless steel. Examples of the corrosion-resistant surface processing include anodic oxidation or ceramic spraying. In addition, an exposed surface (34a) of the shower plate (34) facing the processing chamber (S) may be subjected to a plasma-resistant coating by anodic oxidation or ceramic spraying.

Each of the split metal windows (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) formed by an insulating material is disposed above each split metal window (31), and a high-frequency antenna (inductive coupling antenna) (51) is disposed spaced from the conductor plate (32) by the spacer. The high-frequency antenna (51) contributes to the generation of plasma and is formed by winding an antenna wire formed of a good-conducting metal such as copper into a ring or spiral shape. For example, a plurality of ring-shaped antenna wires may be disposed. Since the high-frequency antenna (51) is disposed on the upper surface of the split metal window (31), it is suspended from the top plate (12) via the split metal window (31). The high-frequency antenna (51) is installed in the antenna room (A) of the upper chamber (13) at the top of the processing vessel (20).

On the lower surface of the conductor plate (32), a gas diffusion groove (33) is formed, and a through hole (32b) is provided that connects the gas diffusion groove (33) and the upper surface (32a) of the conductor plate. At least a part of a gas introduction pipe (52) is embedded in this through hole (32b). On the shower plate (34), a plurality of gas discharge holes (35) are provided that connect 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 outer region of the gas diffusion groove (33) of the conductor plate (32) by a metal screw (not shown). In addition, the gas diffusion groove may be opened on the upper surface of the shower plate. In addition, the shape of the concave portion forming the gas diffusion groove (33) is not limited to the so-called elongated shape, and may also be a concave portion that is widened in a planar shape, and if a space for diffusing gas is formed, the shape of the concave portion is not limited.

Each of the split metal windows (31) is electrically insulated from the support frame (14) and the adjacent split metal windows (31) by an insulating member (37). Here, the insulating member (37) is formed of a fluororesin such as PTFE (Polytetrafluoroethylene). The end surface (37a) of the insulating member (37) facing the processing chamber (S) is flush with the exposed surface (34a) of the shower plate (34) facing the processing chamber (S), and an insulating cover member (38) is disposed across the exposed surface (34a) of the adjacent shower plate (34) while covering the end surface (37a) of the insulating member (37). This cover member (38) is formed of ceramics such as alumina.

The insulating member (37) is formed of a resin such as PTFE, which has high insulating performance and is lightweight, but the plasma resistance of the resin is not high compared to ceramics such as alumina. In addition, it is difficult to perform plasma-resistant coating by anodic oxidation treatment or ceramic spraying on the surface of the resin. Therefore, in the plasma processing device (100), the insulating member (37) is protected from plasma by covering the end face (37a) of the insulating member (37) on the processing chamber (S) side with, for example, a cover member (38) made of ceramic. Each insulating member (37) that insulates the support frame (14) and the partition metal window (31) or adjacent partition metal windows (31) from each other is covered with the cover member (38).

A power supply member (53) that extends above the upper chamber (13) is connected to the high-frequency antenna (51), a power supply line (54) is connected to the upper end of the power supply member (53), and the power supply line (54) is connected to a high-frequency power source (56) through a matching device (55) that performs impedance matching.

By applying high frequency power of, for example, 13.56 MHz from a high frequency power source (56) to a high frequency antenna (51), an induced electric field is formed within the lower chamber (17). By this induced electric field, the processing gas supplied to the processing chamber (S) from the shower plate (34) is converted into plasma, thereby generating an inductively coupled plasma, and ions in the plasma are provided to the substrate (G).

The high-frequency power supply (56) is a source for generating plasma, and the high-frequency power supply (83) connected to the substrate mounting stand (70) serves as a bias source for introducing generated ions. In this way, by generating plasma using two high-frequency power supplies and executing control of ion energy, the generation of plasma and the control of ion energy are executed independently, thereby increasing the degree of freedom of the process.

As shown in Fig. 1, the gas introduction pipes (52) of each split metal window (31) are gathered at one location within the antenna room (A), and the gas introduction pipes (52) extending upward pass through the supply port (12a) opened in the top plate (12) of the upper chamber (13). Then, the gas introduction pipes (52) are connected to a processing gas supply source (64) via a gas supply pipe (61) that is sealed.

An on-off valve (62) and a flow controller (63) such as a mass flow controller are interposed at an intermediate position of a gas supply pipe (61). A processing gas supply section (60) is formed by the gas supply pipe (61), the on-off valve (62), the flow controller (63), and the processing gas supply source (64). In addition, the gas supply pipe (61) is branched at an intermediate position, and an on-off valve, a flow controller, and a processing gas supply source according to the type of processing gas are connected to each branch pipe (not shown).

In plasma processing, the processing gas supplied from the processing gas supply unit (60) is supplied to the gas diffusion groove (33) of the conductor plate (32) of each split metal window (31) through the gas supply pipe (61) and the gas introduction pipe (52). Then, the gas is discharged from each gas diffusion groove (33) through the gas discharge hole (35) of each shower plate (34) to the processing room (S).

In this way, the plasma processing device (100) has a plasma generation unit that generates processing plasma to perform substrate processing (film formation processing, etching processing, etc.) on the substrate (G). The plasma generation unit includes at least a metal window (30) and a high-frequency antenna (51). A high-frequency power source (56) supplies high-frequency power to the high-frequency antenna (51), and a processing gas supply unit (60) supplies processing gas to the processing chamber (S) through a split metal window (31) (processing gas discharge unit). The plasma generation unit forms an induced electric field inside the processing chamber (S) and generates plasma of the processing gas supplied inside the processing chamber (S) by this induced electric field.

The control unit (90) controls the operation of each component of the plasma processing device (100), for example, the chiller (86), the high-frequency power supply (56, 83), the processing gas supply unit (60), the exhaust device (300) based on monitor information transmitted from the pressure gauge, etc. The control unit (90) has a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The CPU executes a predetermined process according to a recipe (process recipe) stored in the memory area of the RAM or ROM. In the recipe, control information of the plasma processing device (100) for process conditions is set. The control information includes, for example, a gas flow rate, a pressure inside the processing vessel (20), a temperature inside the processing vessel (20), a temperature of the substrate (711), a process time, etc.

The program applied by the recipe and control unit (90) may be stored, for example, in a hard disk, a compact disk, an optical magneto-disk, etc. In addition, the recipe, etc. may be stored in a portable computer-readable storage medium such as a CD-ROM, DVD, or memory card and set in the control unit (90) and read. In addition, the control unit (90) has a user interface such as an input device such as a keyboard or mouse for executing input operations of commands, a display device such as a display for visualizing the operating status of the plasma processing device (100), and an output device such as a printer.

Here, the substrate mounting stand (70) is further described using FIGS. 2 and 3. FIG. 2 is an example of a cross-sectional schematic diagram of the substrate mounting stand (70) according to the first embodiment.

The substrate mounting plate (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 (711), a dielectric layer (712), and an adsorption electrode (713) (see FIG. 1; not shown in FIG. 2). A dielectric layer (712) is formed on the upper surface of the base (711), and an adsorption electrode (713) is provided inside the dielectric layer (712). The dielectric layer (712) holds and holds a substrate (G) on its upper surface.

The substrate (711) has conductivity, and high-frequency power is applied from the power supply member (80) (see FIG. 1) through the heating plate (72). In addition, the substrate (711) is preferably made of a material having a small difference in thermal expansion with respect to the dielectric layer (712) at a process temperature (e.g., 250°C). The substrate (711) is made of, for example, stainless steel. As a result, the difference in thermal expansion between the substrate (711) and the dielectric layer (712) is made small, and the dielectric layer (712) is prevented from being peeled off from the substrate (711) due to the difference in thermal expansion between the substrate (711) and the dielectric layer (712) at a high temperature process (e.g., 250°C). In other words, the occurrence of contaminants such as particles due to fragments of the peeled dielectric layer (712), insulation breakdown, and abnormal discharge are prevented. In addition, it is preferable that the surface of the substrate (711) made of stainless steel be covered with a Ni plating layer (714) to prevent the substrate (711) from being corroded by plasma or process gas, etc.

The heating plate (72) is preferably made of a material having conductivity and also good thermal conductivity. The heating plate (72) is made of, for example, aluminum or an aluminum alloy. In addition, the heating plate (72) has a heating element (72a) inside. The heating element (72a) is heated by being supplied with power from an externally provided power source (not shown), and heats the heating plate (72). The upper surface of the heating plate (72) is in contact with the lower surface of the substrate (711), and by the heating element (72a) being heated, heat is transferred from the heating plate (72) to the electrostatic chuck (71), and the substrate (G) mounted on the electrostatic chuck (71) is heated. In addition, when the heat of the plasma generated in the processing chamber (S) is input to the substrate (G), it is transferred to the heating plate (72) via the electrostatic chuck (71).

The cooling plate (73) is preferably made of a material having conductivity and also good thermal conductivity. The cooling plate (73) is made of, for example, aluminum or an aluminum alloy. In addition, the cooling plate (73) has a heat medium passage (73a) inside. A heat medium whose temperature is controlled to a predetermined temperature (for example, 100°C) in a chiller (86) (see FIG. 1) is supplied to the heat medium passage (73a) through a transfer pipe (73b). The heat medium discharged from the heat medium passage (73a) is circulated to the chiller (86) (see FIG. 1) through a return pipe (73c).

Figure 3 is an example of a partially enlarged cross-sectional schematic diagram of a substrate mounting stand (70) according to the first embodiment.

Here, a support member (74) is arranged 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 arranged, for example, by forming a concave portion on the upper surface of the cooling plate (73). It is preferable that the support member (74) be 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 made of, for example, stainless steel. The support members (74) are provided in multiple numbers on the outer periphery of the heating plate (72) and the cooling plate (73) in a circumferential direction, thereby preventing the heating plate (72) and the cooling plate (73) from making direct contact. Meanwhile, in the part where the heating plate (72) and the cooling plate (73) indirectly come into contact via the support member (74), the heat transfer amount decreases because the thermal conductivity of the support member (74) is low. As a result, the heat transfer between the heating plate (72) and the cooling plate (73) via the support member (74) is suppressed. As a result, the support of the heating plate (72) by the cooling plate (73) can be reliably performed while the heat transfer amount between the heating plate (72) and the cooling plate (73) is suppressed to a small extent.

Between the cooling plate (73) and the heating plate (72), a gap space (75) is formed. In addition, in the outer peripheral portion surrounding the gap space (75), a sealing member (76a) (second sealing member) is arranged between the cooling plate (73) and the heating plate (72). The inside of this gap space (75) is sealed with the processing chamber (S) by the sealing member (76a). Although the cooling plate (73) and the heating plate (72) have the sealing member (76a) therebetween, they do not come into direct contact. As with the support member (74), they come into indirect contact via the sealing member (76a). The sealing member (76a) may be arranged, for example, on the outside of the support member (74).

In addition, the gap space (75) may be in communication with the space on the lower side of the cooling plate (73) (a space surrounded by the lower surface of the cooling plate (73), the inner 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. In addition, a sealing member (not shown) may be arranged between the gap space (75) and the space on the lower side of the cooling plate (73), and the gap space (75) may be sealed.

In addition, as shown in Fig. 3, among the surfaces of the heating plate (72), the surface corresponding to the cooling plate (73) is designated as the first surface (S1). Among the surfaces of the cooling plate (73), the surface corresponding to the heating plate (72) is designated as the second surface (S2). Between the cooling plate (73) and the heating plate (72), a gap space (75) is provided that extends in the 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.

In addition, in Fig. 3, a case is described as an example in which a gap space (75) is formed between the cooling plate (73) and the heating plate (72) by forming a concave portion on the upper surface (second surface (S2)) of the cooling plate (73), but it is not limited thereto. It may also be a configuration in which a gap space (75) is formed between the cooling plate (73) and the heating plate (72) by forming a concave portion on the lower surface (first surface (S1)) of the heating plate (72). In addition, it may also be a configuration in which a gap space (75) is formed between the cooling plate (73) and the heating plate (72) by forming concave portions on both sides of the upper surface (first surface (S1)) of the cooling plate (73) and the lower surface (second surface (S2)) of the heating plate (72).

The heating plate (72) has an alumite film (721) formed by performing an alumite treatment on the first surface (S1) exposed to the gap space (75). In other words, the heating plate (72) has an alumite film (721) at least on the wall surface exposed to the gap space (75). In addition, as shown in FIG. 2 and FIG. 3, the heating plate (72) may have an alumite film (721) formed on the entire surface.

The cooling plate (73) has an alumite film (731) formed on the second surface (S2) exposed to the gap space (75). In other words, the cooling plate (73) has an alumite film (731) formed on at least the wall surface exposed to the gap space (75). In addition, as shown in FIG. 2 and FIG. 3, the cooling plate (73) may have an alumite film (731) formed on the entire surface.

In addition, the substrate mounting stand (70) is described as an example in which an alumite film is provided on both sides of the first surface (S1) of the heating plate (72) and the second surface (S2) of the cooling plate (73), but is not limited thereto. The substrate mounting stand (70) may also have a configuration in which an alumite film is provided on at least one side of the first surface (S1) of the heating plate (72) and the second surface (S2) of the cooling plate (73).

The cooling plate (73) is supported by a pedestal (78). A sealing member (76b) is arranged between the cooling plate (73) and the pedestal (78). In addition, a sealing member (76c) is arranged between the pedestal (78) and the bottom plate (16). The space under the cooling plate (73) is sealed with the processing chamber (S) by the sealing members (76b, 76c). In addition, the space under the cooling plate (73) is communicated with the outside of the processing vessel (20) and may be provided with an atmospheric atmosphere.

In addition, sealing members (77) (first sealing members) are provided at various connecting portions in the transfer pipe (73b) and return pipe (73c) through which the heat medium flows. That is, the sealing member (77) prevents the heat medium from leaking to the outside, and by coming into contact with the heat medium, is cooled to a temperature equal to that of the heat medium.

The gap space (75) may be a vacuum atmosphere. In addition, the gap space (75) may be an air atmosphere. In addition, the gap space (75) may be configured to be filled with a heat-conducting gas (e.g., He gas).

Here, an example of processing a substrate (G) by a plasma processing device (100) is described.

First, the substrate (G) is mounted on the substrate mounting stand (70) and electrostatically adsorbed using an electrostatic chuck (71).

Next, a process of heating the electrostatic chuck (71) by the heating plate (72) is executed. Here, the control unit (90) controls the power supply (not shown) that supplies power to the heating element (72a) based on the detection temperature of a temperature sensor (not shown) such as a thermocouple provided on the substrate (711). As a result, the heating plate (72), the electrostatic chuck (71) including the substrate (711), and the substrate (G) mounted on the electrostatic chuck (71) are each temperature-regulated to a desired temperature (for example, 250°C). Meanwhile, a heat medium having a lower temperature (for example, 100°C) than the desired temperature flows through the heat medium passage (73a) of the cooling plate (73), so that the temperature of the cooling plate (73) also becomes a low temperature (for example, 100°C).

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 device (100) to perform film-forming plasma processing on the substrate (G). When performing plasma processing on the substrate (G), plasma is generated in the processing chamber (S), and heat from the plasma is input to the substrate (G) and the substrate mounting stand (70). The heat from the plasma is transferred to the heating plate (72) through 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 radiated from the first surface (S1) of the heating plate (72) to the gap space (75). And, the radiant heat radiated from the heating plate (72) to the gap space (75) is heat-absorbed on the second surface (S2) of the cooling plate (73). At this time, the alumite film covering the first surface (S1) and the second surface (S2) has high heat emissivity and absorption rate, as described later. That is, by forming the alumite film (721) on the first surface (S1), heat dissipation is efficiently performed, and by forming the alumite film (731) on the second surface (S2), heat absorption is efficiently performed. Therefore, in the gap space (75), heat transfer by efficient heat radiation is performed from the first surface (S1) to the second surface (S2). And, the heat is radiated to the heat medium flowing through the heat medium passage (73a) in the cooling plate (73). In this way, the substrate (G) and the electrostatic chuck (71) are dissipated through heat exchange via the gap space (75) by the cooling plate (73).

In addition, a process of adjusting the temperature of the substrate (G) through the electrostatic chuck (71) is executed. Here, the control unit (90) controls the power supply (not shown) that supplies power to the heating element (72a) based on the detected temperature of a temperature sensor (not shown) such as a thermocouple provided on the substrate (711).

By these processes, the temperature of the substrate (G) is controlled to a desired temperature during substrate processing.

In this way, according to the substrate mounting stand (70) illustrated in FIGS. 2 and 3, the substrate (G) can be processed by a high-temperature process (e.g., 250°C). In addition, when the heat of plasma is input to the substrate (G) or the substrate mounting stand (70), the heat can be dissipated to the heat medium.

In addition, the temperature of the heat medium flowing through the transfer pipe (73b) or the return pipe (73c) can be set to a temperature (e.g., 100°C) lower than the temperature of the high-temperature process of the substrate (G) (e.g., 250°C). As a result, it is possible to suppress the sealing member (77) provided in the transfer pipe (73b) or the return pipe (73c) from being deteriorated by heat.

Here, heat radiation and heat absorption by the alumite film are explained using Fig. 4. Fig. 4 is an example of a table showing the relationship between various alumite treatments and emissivity.

In the table of Fig. 4, Nos. 1 to 15 perform various alumite treatments on the substrate of aluminum alloy (A5052). Some of the alumite treatments of Nos. 1 to 15 are treatments that form alumite by different methods. The first comparative example, No. 16, shows the substrate of an aluminum alloy (A5052) that has not been treated (before performing the alumite treatment). The second to fourth comparative examples, Nos. 17 to 19, perform blast treatment on the substrate of the aluminum alloy (A5052) shown in No. 16 to change the surface roughness (substrate surface finish). For Nos. 1 to 19, the substrate surface finish (arithmetic mean roughness (Ra)), treatment, alumite film thickness, substrate temperature at the time of measuring emissivity, and emissivity are respectively shown.

As shown in Fig. 4, the untreated emissivity shown in No. 16 is 0.38. In contrast, for the various alumite treatments and film thicknesses shown in No. 1 to No. 15, the emissivity is shown to have a high value close to 1. That is, by forming an alumite film on the surface of the substrate, the emissivity is improved.

Here, in the various alumite treatments shown in No. 1 to No. 15, the surface finish (arithmetic mean roughness (Ra)) of the substrate is larger than that of the untreated state shown in No. 16. That is, the surface area is increased. Therefore, in No. 17 to No. 19, the surface area of the substrate was increased by blast treatment.

In the various blast treatments shown in No. 17 to No. 19, no increase in emissivity was observed.

In this way, regardless of the method of alumite treatment, by providing an alumite film on the surface of the substrate, the emissivity is improved. That is, by providing an alumite film (721) on the surface of the heating plate (72), the radiant heat from the heating plate (72) to the gap space (75) can be increased. In addition, generally, when the emissivity of heat is high, the heat absorption rate also increases, so an increase in heat radiation indicates an increase in heat absorption. Therefore, the absorption of radiant heat from the gap space (75) to the cooling plate (73) can also be increased.

By this, the heat of the plasma can be preferably transferred from the heating plate (72) to the cooling plate (73) through the gap space (75).

Here, a substrate mounting stand (70C) according to a reference example is described. Fig. 5 is an example of a cross-sectional schematic diagram of a substrate mounting stand (70C) according to a reference example.

In the substrate mounting stand (70C) according to the reference example, a heating plate (72) is not provided, and a cooling plate (73) is provided directly under the substrate (711).

Here, in the substrate mounting stand (70C) according to the reference example, a case where the substrate (G) is processed by a high temperature process (e.g., 250°C) is explained as an example. A high temperature heat medium (e.g., 250°C) is circulated in the heat medium path (73a) of the cooling plate (73). Therefore, the seal member (77) and the seal member (76b) are also exposed to high temperatures. Therefore, there is a concern that the seal member (77) and the seal member (76b) may deteriorate due to heat, resulting in an increase in the frequency of replacement, etc.

In this regard, in the substrate mounting stand (70) illustrated in FIGS. 2 and 3, even when the substrate (G) is processed by a high-temperature process (e.g., 250°C), a heat medium having a lower temperature (e.g., 100°C) than the desired process temperature flows through the heat medium path (73a) of the cooling plate (73), and the cooling plate (73) can be maintained at a low temperature. For this reason, it is possible to suppress the seal member (77) and the seal member (76b) from being deteriorated due to heat, etc.

Fig. 6 is an example of a cross-sectional schematic diagram of a substrate mounting stand (70A) according to the second embodiment.

As illustrated in Fig. 6, the substrate mounting stand (70A) is provided with a gas passage (89a) communicating with a gap space (75), an opening/closing valve (89b1, 89b2) provided in the gas passage (89a), a pressure sensor (89c) provided in the gas passage (89a) and detecting the pressure of the gap space (75), a gas supply source (89d1), and an exhaust device (89d2). In addition, although not illustrated in Fig. 6, a sealing member (not illustrated) is arranged around an opening (see Fig. 1) of a cooling plate (73) through which a power supply member (80) is inserted, so that the gap space (75) and the space on the lower side of the cooling plate (73) are sealed. Thereby, the gap space (75) is formed such that the upper surface is partitioned into a first surface (S1), the lower surface is partitioned into a second surface (S2), the outer circumference is partitioned into a seal member (76a), and the inner circumference is partitioned into a seal member (not shown).

By opening the on-off valve (89b1), gas is charged into the gap space (75) from the gas supply source (89d1) through the gas passage (89a). The gas charged into the gap space (75) may be the atmosphere or a heat-conducting 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 to the exhaust device (89d2) through the gas passage (89a).

In this way, the substrate mounting base (70A) can control the pressure (charge amount) of the gas within the gap space (75). In addition, the pressure (charge amount) of the heat-conducting gas within the gap space (75) can be controlled. As a result, heat transfer by convection through the heat-conducting gas can be controlled. That is, the amount of heat transfer from the heating plate (72) to the cooling plate (73) can be controlled by the heat-conducting gas, along with heat transfer by radiation.

Here, an example of processing a substrate (G) by a plasma processing device (100) equipped with a substrate mounting stand (70A) according to the second embodiment is described.

First, a process of filling the gap space (75) with atmospheric or heat-conducting gas is performed. That is, the heat-conducting characteristics of the heating plate (72) and the cooling plate (73) are adjusted. As a result, for example, the heat-conducting characteristics of the heating plate (72) and the cooling plate (73) can be adjusted according to the substrate processing process. In addition, in a substrate processing system having a plurality of plasma processing devices (100), the difference in the heat-conducting characteristics of the heating plate (72) and the cooling plate (73) can be adjusted.

Above, the plasma processing device (100) has been described, but the present disclosure is not limited to the above-described embodiments, etc., and various modifications and improvements are possible within the scope of the gist of the present disclosure described in the scope of the patent claims. In addition, although the case of performing a film formation process as the substrate process has been described, it is not limited to this, and can be applied to etching process, ashing process, etc. when the substrate mounting table becomes high temperature.

G: Substrate 20: Processing vessel
70: PCB mounting base 71: Electrostatic chuck
711: Description 711a: Description Top
712: Dielectric layer 713: Adsorption electrode
714: Ni plating layer 72: Heating plate
72a: Heating element 721: Alumite film
73: Cooling plate 73a: Heat medium flow path
73b: Transfer pipe 73c: Return pipe
731: Alumite film 74: Support member
75: Gap space 76a to 76c, 77: Absence of seal
78: Pedestal 79: Focus Ring
89a: Gas passage 89b1: Shut-off valve
89b2: Shut-off valve 89c: Pressure sensor
89d1: Gas supply source 89d2: Exhaust device
S1: Side 1 S2: Side 2
90: Control unit 100: Plasma processing unit

Claims (12)

It is installed inside a processing container that performs processing on a substrate, and is on a substrate mounting stand that mounts the substrate.
The above substrate mounting stand is,
An electrostatic chuck comprising a substrate having a dielectric layer with an adsorption electrode built into the mounting surface on which the substrate is mounted,
A heating plate made of aluminum or aluminum alloy connected to the lower side of the above electrostatic chuck,
It has a cooling plate made of aluminum or aluminum alloy connected to the lower side of the above heating plate,
The surface of the heating plate corresponding to the cooling plate is referred to as the first surface,
The surface of the cooling plate corresponding to the heating plate is referred to as the second surface,
Between the heating plate and the cooling plate, there is a gap space extending in the direction along the first surface and the second surface,
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 alumite film.
Board mounting bracket. In paragraph 1,
In the above gap space, the distance between the first surface and the second surface is 2 mm or more and 10 mm or less.
Board mounting bracket. In paragraph 1,
The above heating plate has a heating element,
The above cooling plate has a heat medium path for circulating the heat medium.
Board mounting bracket. In the third paragraph,
In the transfer pipe and return pipe connected to the above heat medium path, a first seal member is arranged.
Board mounting bracket. In paragraph 1,
The above heating plate is supported on the cooling plate via a support member.
Board mounting bracket. In paragraph 1,
A second sealing member is arranged between the heating plate and the cooling plate surrounding the gap space.
Board mounting bracket. In paragraph 6,
The above gap space is filled with atmospheric or heat-conducting gas.
Board mounting bracket. In a substrate processing device for processing a substrate,
A processing vessel for performing processing on the substrate inside,
It is installed inside the above processing container and has a substrate mounting stand for mounting the substrate.
The above substrate mounting stand is,
An electrostatic chuck comprising a substrate having a dielectric layer with an adsorption electrode built into the mounting surface on which the substrate is mounted,
A heating plate made of aluminum or aluminum alloy connected to the lower side of the above electrostatic chuck,
It has a cooling plate made of aluminum or aluminum alloy connected to the lower side of the above heating plate,
The surface of the heating plate corresponding to the cooling plate is referred to as the first surface,
The surface of the cooling plate corresponding to the heating plate is referred to as the second surface,
Between the heating plate and the cooling plate, there is a gap space extending in the direction along the first surface and the second surface,
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 alumite film.
Substrate processing device. In Article 8,
The above heating plate has a heating element,
The above cooling plate has a heat medium path for circulating the heat medium,
In the transfer pipe and return pipe connected to the above heat medium path, a first seal member is arranged.
Substrate processing device. In a substrate processing method in which a substrate is processed inside a processing container,
A substrate mounting stand for mounting the substrate is provided inside the above processing container,
The above substrate mounting stand is,
An electrostatic chuck comprising a substrate having a dielectric layer with an adsorption electrode built into the mounting surface on which the substrate is mounted,
A heating plate made of aluminum or aluminum alloy connected to the lower side of the above electrostatic chuck,
It has a cooling plate made of aluminum or aluminum alloy connected to the lower side of the above heating plate,
The surface of the heating plate corresponding to the cooling plate is designated as the first surface, the surface of the cooling plate corresponding to the heating plate is designated as the second surface, and a gap space is provided between the heating plate and the cooling plate, the gap space extending in the direction along the first surface and the second surface.
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 alumite film,
A process for heating the electrostatic chuck by the heating plate,
A process of dissipating heat from the electrostatic chuck through the heating plate by the cooling plate through heat exchange through the gap space,
A process for adjusting the temperature of the substrate by passing through the electrostatic chuck
Method of substrate processing. In Article 10,
Having a process of filling the above gap space with atmospheric or heat-conducting gas.
Method of substrate processing. In Article 10,
The above treatment performs film formation on the substrate.
Method of substrate processing.