JP7710322B2 - Mounting table and substrate processing apparatus - Google Patents

Description

This disclosure relates to a mounting table and a substrate processing apparatus.

Patent document 1 discloses a mounting table in which bands are provided concentrically on the surface of an electrostatic check to divide the space between the electrostatic check and the substrate placed on it into concentric sections, and cooling gas is supplied to each space.

Special Publication No. 2020-512692

This disclosure provides technology that improves the cooling capacity of the mounting table.

A mounting table according to one aspect of the present disclosure includes a mounting portion, an annular support portion, a gas supply port, a supply flow path, a gas exhaust port, and an exhaust flow path. The mounting portion has a mounting surface on which a substrate is mounted. The annular support portion is provided on the mounting surface along the outer periphery of the substrate and supports the substrate. The gas supply port is formed on the mounting surface and supplies a heat transfer gas to a space between the substrate and the mounting surface. The supply flow path is provided within the mounting portion and supplies the heat transfer gas to the gas supply port. The gas exhaust port is formed on the mounting surface and exhausts the heat transfer gas in the space. The exhaust flow path is provided within the mounting portion and allows the heat transfer gas exhausted from the gas exhaust port to flow. The supply flow path is provided such that at least the gas supply port side is inclined with respect to the mounting surface.

This disclosure makes it possible to increase the cooling capacity of the mounting table.

FIG. 1 is a diagram showing an example of a schematic configuration of a plasma processing system according to an embodiment. FIG. 2 is a diagram illustrating an example of a schematic configuration of a substrate support portion according to the embodiment. FIG. 3 is a diagram showing an example of a cross section of the substrate support part according to the embodiment taken along line AA in FIG. FIG. 4 is a diagram showing an example of a cross section of the substrate support part according to the embodiment taken along line BB in FIG. FIG. 5 is a diagram showing an example of a cross section of the substrate support part according to the embodiment taken along line CC in FIG. FIG. 6 is a diagram illustrating an example of the configuration of a conventional substrate support portion. FIG. 7 is a diagram illustrating an example of the configuration of a substrate support portion according to an embodiment. FIG. 8 is a diagram illustrating an example of a flow of heat transfer gas near a gas supply port of the substrate support according to the embodiment. FIG. 9 is a diagram showing an example of exhaust characteristics of a gas exhaust port according to the embodiment. FIG. 10 is a diagram illustrating an example of a cross section of a substrate support portion according to an embodiment. FIG. 11 is a diagram showing an example of exhaust characteristics of a gas exhaust port according to the embodiment. FIG. 12 is a diagram illustrating an example of a flow of heat transfer gas within the space of the substrate support part according to the embodiment. FIG. 13 is a diagram illustrating an example of a flow of heat transfer gas within the space of the substrate support part according to the embodiment. FIG. 14 is a diagram illustrating an example of a flow of heat transfer gas on the substrate supporting surface of the substrate supporting part according to the embodiment. FIG. 15 is a diagram illustrating another example of the flow of heat transfer gas on the substrate supporting surface of the substrate supporting part according to the embodiment.

Below, an embodiment of the mounting table and substrate processing apparatus disclosed in the present application will be described in detail with reference to the drawings. Note that the disclosed mounting table and substrate processing apparatus are not limited to the present embodiment.

Substrate processing apparatuses are known that perform substrate processing such as film formation and etching on substrates such as semiconductor wafers (hereinafter referred to as "wafers"). Some substrate processing apparatuses electrostatically attract the substrate to a mounting table. Such a mounting table is provided with, for example, an electrostatic chuck that electrostatically attracts the substrate. A heat transfer gas is supplied between the electrostatic chuck and the substrate.

In recent years, depending on the process, it is desirable to lower the temperature of the substrate. For example, in the HARC (High Aspect Ratio Contact) process, which forms holes with a high aspect ratio, it is desirable to lower the temperature of the substrate. Conventionally, the space between the substrate and the electrostatic chuck is a sealed space filled with a heat transfer gas. As a result, the heat removal from the substrate is limited to the cooling capacity of the heat transfer gas.

Therefore, there is a need for technology that can improve the cooling capacity of the mounting table.

[Embodiment]
[Device configuration]
An example of a substrate processing apparatus according to the present disclosure will be described. In the embodiment, the substrate processing apparatus according to the present disclosure will be described as a plasma processing system having a system configuration. FIG 1 is a diagram showing an example of a schematic configuration of a plasma processing system according to an embodiment.

An example of the configuration of a plasma processing system is described below. The plasma processing system includes a capacitively coupled plasma processing device 1 and a control unit 2. The capacitively coupled plasma processing device 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing device 1 also includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is disposed in the plasma processing chamber 10. The shower head 13 is disposed above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, the sidewall 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s and at least one gas exhaust port for exhausting gas from the plasma processing space. The sidewall 10a is grounded. The shower head 13 and the substrate support 11 are electrically insulated from the plasma processing chamber 10 housing.

The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region (substrate support surface) 111a for supporting a substrate (wafer) W, and an annular region (ring support surface) 111b for supporting the ring assembly 112. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. In one embodiment, the main body 111 includes a base and an electrostatic chuck. The base includes a conductive member. The conductive member of the base functions as a lower electrode. The electrostatic chuck is disposed on the base. The upper surface of the electrostatic chuck has a substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Although not shown, the substrate support 11 may include a temperature adjustment module configured to adjust at least one of the electrostatic chuck, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a.

For example, the substrate support part 11 has a flow path 111c formed in the main body part 111 for flowing a temperature control medium therein. The flow path 111c corresponds to the substrate support surface 111a on which the substrate W is placed, and is formed over the entire surface of the substrate support surface 111a. A temperature control medium such as a refrigerant or heat medium flows through the flow path 111c. For example, the flow path 111c is connected to a chiller unit 114 via piping 113. The chiller unit 114 is capable of controlling the temperature of the refrigerant it supplies. The plasma processing apparatus 1 is configured to be capable of controlling the temperature of the substrate support part 11 by circulating a temperature-controlled refrigerant from the chiller unit 114 through the flow path 111c.

In addition, a gas supply port 111d for discharging a heat transfer gas is formed on the substrate support surface 111a of the substrate support part 11. The substrate support part 11 is provided with a supply flow path 115 such as a pipe for supplying the heat transfer gas. The supply flow path 115 is connected to the gas supply port 111d. A gas supply unit 116 is connected to the supply flow path 115. The gas supply unit 116 supplies a heat transfer gas such as He gas to the supply flow path 115. The heat transfer gas supplied via the supply flow path 115 is discharged from the gas supply port 111d and supplied to the space between the substrate W and the substrate support surface 111a.

In addition, a gas exhaust port 111e is formed on the substrate support surface 111a of the substrate support part 11. The substrate support part 11 is provided with an exhaust passage 117, such as a pipe for exhausting heat transfer gas. The exhaust passage 117 is connected to the gas exhaust port 111e. The exhaust passage 117 is connected to the exhaust system 40. The heat transfer gas supplied to the space between the substrate W and the substrate support surface 111a flows to the gas exhaust port 111e and is exhausted to the exhaust system 40 via the exhaust passage 117.

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

The gas supply 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply 20 is configured to supply at least one process gas from a respective gas source 21 through a respective flow controller 22 to the showerhead 13. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

The power source 30 includes an RF power source 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power source 31 is configured to supply at least one RF signal (RF power), such as a source RF signal and a bias RF signal, to the conductive member of the substrate support 11 and/or the conductive member of the showerhead 13. This causes a plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power source 31 can function as at least a part of a plasma generating unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to the conductive member of the substrate support 11, a bias potential is generated on the substrate W, and ion components in the formed plasma can be attracted to the substrate W.

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

The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to a conductive member of the substrate support 11 and configured to generate a first DC signal. The generated first bias DC signal is applied to the conductive member of the substrate support 11. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to a conductive member of the showerhead 13 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 13. In various embodiments, at least one of the first and second DC signals may be pulsed. The first and second DC generating units 32a and 32b may be provided in addition to the RF power source 31, or the first DC generating unit 32a may be provided in place of the second RF generating unit 31b.

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

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

Next, the configuration of the substrate support part 11 according to the embodiment will be described. FIG. 2 is a diagram showing an example of a schematic configuration of the substrate support part 11 according to the embodiment. FIG. 2 shows a plan view of the substrate support surface 111a of the substrate support part 11 on which the substrate W is placed.

As shown in FIG. 2, the main body 111 of the substrate support 11 has a substrate support surface 111a for supporting the substrate W. The substrate W is placed on the substrate support surface 111a of the main body 111. In the embodiment, the substrate support 11 corresponds to the mounting table of the present disclosure. Also, the main body 111 corresponds to the mounting portion of the present disclosure.

A circular band 111f is provided on the substrate support surface 111a along the outer periphery of the substrate W. The band 111f supports the outer periphery of the substrate W placed on the substrate support surface 111a. Dots (not shown) that support the substrate W are formed on the substrate support surface 111a.

Gas supply ports 111d and gas exhaust ports 111e are formed on the substrate support surface 111a. The gas supply ports 111d are formed at multiple positions on the substrate support surface 111a in a concentric manner. In the example of FIG. 2, multiple gas supply ports 111d are formed at intervals on the circumference of two concentric circles with different radii. The gas supply ports 111d are formed at larger intervals on the circumference of the outer concentric circle than on the circumference of the inner concentric circle. Each gas supply port 111d is connected to a supply flow path 115 and discharges a heat transfer gas supplied from the supply flow path 115. Note that the arrangement positions of the gas supply ports 111 shown in FIG. 2 are merely examples and are not limited thereto.

FIG. 3 is a diagram showing an example of a cross section of the substrate support part 11 according to the embodiment taken along line A-A in FIG. 2. FIG. 3 shows a cross section of the gas supply port 111d taken along line A-A in FIG. 2. The main body part 111 includes a base 120 and an electrostatic chuck 121. The base 120 includes a conductive member. For example, the base 120 is formed of a conductive metal such as aluminum. The electrostatic chuck 121 has an insulating layer such as ceramic and a film-like electrode provided within the insulating layer. The electrostatic chuck 121 generates an electrostatic attraction force by applying a DC voltage from a power source (not shown) to an electrode provided inside the electrostatic chuck 121, thereby attracting and holding the substrate W. The electrostatic chuck 121 is bonded to the base 120 with an adhesive. An adhesive layer 122 is formed between the electrostatic chuck 121 and the base 120.

The bands 111f and dots (not shown) provided on the substrate support surface 111a support the substrate W, forming a space 123 between the substrate W and the substrate support surface 111a. The bands 111f come into contact with the outer periphery of the substrate W, making the space 123 a sealed space with a sealed periphery. A heat transfer gas is supplied to the space 123 from the gas supply port 111d.

The base 120 is provided with sleeves 120a that form the supply flow passages 115 at the positions of the gas supply ports 111d. Each gas supply port 111d is connected to each supply flow passage 115. At least the gas supply port 111d side of each supply flow passage 115 is inclined with respect to the substrate support surface 111a. In the example of FIG. 2, the gas supply port 111d side of the supply flow passage 115 is inclined with respect to the substrate support surface 111a in one circumferential direction of the concentric circle of the gas supply port 111d. In the main body 111 according to the embodiment, the gas supply port 111d side of each supply flow passage 115 is inclined in the clockwise direction with respect to the substrate support surface 111a. As a result, the heat transfer gas is discharged from each gas supply port 111d in the counterclockwise direction of the concentric circle. In FIG. 2, the direction of the heat transfer gas discharged from each gas supply port 111d is indicated by an arrow.

As shown in FIG. 2, a plurality of gas exhaust ports 111e are formed in a concentric shape on the substrate support surface 111a with a different radius from the concentric circle of the gas supply port 111d. In the example of FIG. 2, the gas exhaust port 111e is formed at the center of the concentric circle. A plurality of gas exhaust ports 111e are formed at intervals on the circumference of a concentric circle with a radius larger than the radius of the inner concentric circle of the gas supply port 111d and smaller than the radius of the outer concentric circle of the gas supply port 111d. Note that the arrangement position of the gas exhaust ports 111e shown in FIG. 2 is one example and is not limited to this.

Figure 4 is a diagram showing an example of a cross section of the substrate support part 11 according to the embodiment taken along line B-B in Figure 2. Figure 4 shows a cross section of the gas exhaust port 111e taken along line B-B in Figure 2. The base 120 is provided with sleeves 120b constituting the exhaust flow path 117 at the positions of the gas exhaust ports 111e. Each gas exhaust port 111e is connected to the exhaust flow path 117. In this embodiment, the exhaust flow path 117 is provided perpendicular to the substrate support surface 111a. Note that the exhaust flow path 117 may be provided with at least the gas supply port 111d side inclined with respect to the substrate support surface 111a. The heat transfer gas supplied to the space 123 is exhausted from the gas exhaust port 111e.

As shown in FIG. 2, the substrate support surface 111a is provided with a concentrically spaced current plate 111g between the concentric circle of the gas supply port 111d and the concentric circle of the gas exhaust port 111e. Note that the arrangement position of the current plate 111g shown in FIG. 2 is an example and is not limited thereto.

Figure 5 is a diagram showing an example of a cross section of the substrate support part 11 according to the embodiment taken along line CC in Figure 2. Figure 5 shows a cross section of the current plate 111g taken along line CC in Figure 2. Figure 5 shows dots 111h provided on the substrate support surface 111a. As described above, the substrate W is supported by the bands 111f and dots 111h provided on the substrate support surface 111a. A space 123 is formed between the substrate W and the substrate support surface 111a. The current plate 111g is provided on the substrate support surface 111a. The current plate 111g is formed lower than the dots 111h, and a gap is provided without contacting the substrate W. Although there is a gap between the current plate 111g and the substrate W, the current plate 111g separates the space 123. The flow direction of the heat transfer gas supplied to the space 123 is controlled by the current plate 111g.

When performing plasma processing, the plasma processing apparatus 1 according to the embodiment controls the temperature of the substrate support 11 by cooling the coolant from the chiller unit 114 via the piping 113 and circulating the coolant through the flow path 111c. In addition, the plasma processing apparatus 1 supplies heat transfer gas from the gas supply unit 116 through the supply flow path 115 and the gas supply port 111d to the space 123, and exhausts the heat transfer gas in the space 123 from the gas exhaust port 111e and the exhaust flow path 117 to form a flow of heat transfer gas in the space 123.

Here, conventionally, the space 123 between the substrate W and the substrate support surface 111a was a sealed space, and was simply filled with a heat transfer gas. FIG. 6 is a schematic diagram showing an example of the configuration of a conventional substrate support part 11. In the conventional substrate support part 11, the space 123 between the substrate W and the substrate support surface 111a was a sealed space, and was simply filled with a heat transfer gas through the supply flow path 115 and the gas supply port 111d. For this reason, heat removal from the substrate W was limited to cooling by heat transfer from the filled heat transfer gas. During plasma processing, the heat transferred from the plasma to the substrate W is transferred to the coolant in the flow path 111c through the heat transfer gas and the substrate support part 11, and is removed. During plasma processing, the substrate W and the substrate support part 11 have a transient state and a steady state. The transient state is, for example, a state in which the heat input to the substrate W and the substrate support 11 is greater than the heat output, and the temperatures of the substrate W and the substrate support 11 tend to rise over time. The steady state is a stable state in which the heat input and heat output of the substrate W and the substrate support 11 are equal, the temperature of the substrate W and the substrate support 11 no longer tends to rise over time, and the temperature is approximately constant. In the steady state, the heat input from the plasma to the substrate W is equal to the heat output removed by heat transfer to the coolant. For example, when the heat that can be removed by circulating the coolant through the flow path 111c is 10 W, the plasma processing apparatus 1 can perform plasma processing up to a power with a heat input of 10 W to the substrate W. The higher the plasma power, the greater the heat input to the substrate W in the plasma processing apparatus 1. For this reason, when performing plasma processing with a higher power, the plasma processing apparatus 1 needs to increase its cooling capacity.

The plasma processing apparatus 1 according to the embodiment supplies heat transfer gas from the gas supply unit 116 to the space 123, exhausts the heat transfer gas from the space 123, and forms a flow of heat transfer gas in the space 123.

FIG. 7 is a schematic diagram showing an example of the configuration of the substrate support part 11 according to the embodiment. In the space 123 between the substrate W and the substrate support surface 111a, a heat transfer gas flows from the supply flow path 115 to the exhaust flow path 117. During plasma processing, the heat transferred from the plasma to the substrate W is transferred to the refrigerant in the flow path 111c via the heat transfer gas and the substrate support part 11, and the heat transfer gas to which the heat has been transferred is exhausted to the exhaust flow path 117 and removed. In the plasma processing apparatus 1 according to the embodiment, the cooling capacity is increased by the amount that the heat transfer gas to which the heat has been transferred flows into the exhaust flow path 117 and is exhausted. As a result, the plasma processing apparatus 1 according to the embodiment can perform plasma processing with a higher power. For example, if the amount of heat that can be removed by circulating the refrigerant in the flow path 111c is 10 W and the amount of heat that can be removed by flowing the heat transfer gas in the space 123 is 5 W, the plasma processing apparatus 1 can perform plasma processing with a power of up to 15 W of heat input to the substrate W.

The cooling capacity of cooling devices that cool refrigerants, such as the chiller unit 114, tends to increase as the size of the device increases. In the case of conventional configurations, in order to increase the cooling capacity, the cooling device needs to be enlarged, which increases the size of the plasma processing device 1 and the installation area. In factories that manufacture semiconductor devices using the plasma processing device 1, the area available for installing the plasma processing device 1 is limited. For this reason, in a factory, if the installation area for the plasma processing device 1 increases, the number of plasma processing devices 1 that can be installed decreases, and production capacity decreases.

On the other hand, the plasma processing apparatus 1 according to the embodiment can increase the cooling capacity of the substrate support portion 11 without increasing the cooling capacity of the cooling device. This makes it possible to prevent an increase in the installation area of the plasma processing apparatus 1. This makes it possible to prevent a decrease in the number of plasma processing apparatuses 1 that can be installed in a factory, thereby preventing a decrease in production capacity.

In addition, as shown in FIG. 2, the substrate support part 11 according to the embodiment has gas supply ports 111d formed at multiple positions concentrically on the substrate support surface 111a. In addition, the gas supply port 111d side of the supply flow passage 115 communicating with each gas supply port 111d of the substrate support part 11 is inclined in the clockwise direction of the concentric circle of the gas supply port 111d. As a result, a flow of heat transfer gas in the counterclockwise direction is generated in the space 123. As shown in FIG. 2, the substrate support part 11 has multiple gas exhaust ports 111e formed concentrically with a radius different from that of the concentric circle of the gas supply port 111d. The heat transfer gas discharged from the gas supply port 111d circulates in the space 123 without being immediately discharged from the gas exhaust port 111e. As a result, the heat transfer gas can be circulated in the space 123 for a long period of time, thereby improving the cooling capacity of the substrate support surface 111a. In addition, the substrate support surface 111a is provided with a flow straightening plate 111g spaced apart from the gas supply port 111d and the gas exhaust port 111e. This allows the heat transfer gas to circulate stably within the space 123. This allows the entire substrate support surface 111a to be cooled by the heat transfer gas.

In the substrate support part 11 according to the embodiment, the gas supply port 111d side of the supply flow passage 115 is inclined with respect to the substrate support surface 111a. FIG. 8 is a diagram for explaining an example of the flow of the heat transfer gas near the gas supply port 111d of the substrate support part 11 according to the embodiment. The heat transfer gas is discharged obliquely from the gas supply port 111d. This allows a turbulent flow of the heat transfer gas to be generated in the space 123. Here, for example, when the flow of the heat transfer gas in the space 123 becomes laminar, a boundary layer with a slow flow is formed near the substrate W and the substrate support surface 111a in the space 123, and the propagation of heat is suppressed. As a result, the thermal conductivity of the heat transfer gas is reduced in the space 123. As shown in FIG. 8, the substrate support part 11 according to the embodiment can suppress the formation of a boundary layer in the space 123 by generating a turbulent flow of the heat transfer gas in the space 123. This allows a decrease in the thermal conductivity of the heat transfer gas in the space 123 to be suppressed.

The exhaust flow path 117 may be provided perpendicular to the substrate support surface 111a, or at least the gas supply port 111d side may be provided at an incline with respect to the substrate support surface 111a. In the above-mentioned FIG. 4, the exhaust flow path 117 communicating with the gas exhaust port 111e is provided perpendicular to the substrate support surface 111a. FIG. 9 is a diagram showing an example of the exhaust characteristics of the gas exhaust port 111e according to the embodiment. In the case of FIG. 4, as shown in FIG. 9, the gas exhaust port 111e draws in the heat transfer gas in the same manner all around. Therefore, the gas exhaust port 111e has the same exhaust characteristics all around. FIG. 10 is a diagram showing an example of a cross section of the substrate support part 11 according to the embodiment. In FIG. 10, the exhaust flow path 117 communicating with the gas exhaust port 111e is provided at an incline with respect to the substrate support surface 111a. The smaller the angle change when the heat transfer gas flows into the gas exhaust port 111e, the smoother the heat transfer gas flows into the gas exhaust port 111e. Therefore, the gas exhaust port 111e strongly draws in the heat transfer gas on the opposite side of the inclination. FIG. 11 is a diagram showing an example of the exhaust characteristics of the gas exhaust port 111e according to the embodiment. The gas exhaust port 111e is connected to an exhaust passage 117 that is inclined to the right with respect to the substrate support surface 111a. Therefore, the gas exhaust port 111e shown in FIG. 11 strongly draws in the heat transfer gas on the left side, which is the opposite side of the inclination of the exhaust passage 117.

In this way, the exhaust characteristics of the gas exhaust port 111e change depending on the orientation of the exhaust flow path 117. The position of the gas exhaust port 111e and the orientation of the exhaust flow path 117 are designed depending on how the heat transfer gas in the space 123 of the substrate support part 11 is to be exhausted.

Figure 12 is a diagram showing an example of the flow of heat transfer gas in the space 123 of the substrate support part 11 according to the embodiment. In Figure 12, the exhaust flow path 117 of the gas supply port 111d is provided at an acute angle with respect to the substrate support surface 111a in the flow direction of the heat transfer gas in the space 123. In this case, the heat transfer gas can be smoothly flowed to the gas supply port 111d, and a large amount of the heat transfer gas can be exhausted. Figure 13 is a diagram showing an example of the flow of heat transfer gas in the space 123 of the substrate support part 11 according to the embodiment. In Figure 13, the exhaust flow path 117 of the gas supply port 111d is provided at an obtuse angle with respect to the substrate support surface 111a in the flow direction of the heat transfer gas in the space 123. In this case, a part of the heat transfer gas can be sucked in while the heat transfer gas is flowing. In addition, turbulence can be generated near the gas supply port 111d.

However, the substrate support part 11 may have hot spots, where the temperature is high, and cold spots, where the temperature is low, on the substrate support surface 111a. The substrate support part 11 is prone to hot spots and cold spots at locations where other members are provided, such as locations where lifter pins that raise and lower the substrate W are provided. Hot spots and cold spots are prone to becoming singular points because the temperature at the corresponding location on the substrate W placed thereon differs from the surrounding area.

Therefore, the substrate support 11 may be provided with a gas supply port 111d and a supply passage 115 so that the flow rate of the heat transfer gas is increased relative to the hot spot. The substrate support 11 may also be provided with a gas supply port 111d and a supply passage 115 so that the flow rate of the heat transfer gas is decreased relative to the cold spot. FIG. 14 is a diagram showing an example of the flow of the heat transfer gas on the substrate support surface 111a of the substrate support 11 according to the embodiment. Three hot spots HS are generated near the center of the substrate support surface 111a. FIG. 14 shows only some of the gas supply ports 111d and gas exhaust ports 111e provided on the substrate support surface 111a. In FIG. 14, the gas supply port 111d, the supply passage 115, the gas exhaust port 111e, and the exhaust passage 117 are provided so that three arc-shaped heat transfer gas flows passing through the hot spots HS are generated. A plurality of gas supply ports 111d are formed on the substrate support surface 111a along the flow of the heat transfer gas so that a flow of the heat transfer gas occurs toward the hot spot HS. The supply flow passages 115 are provided at an incline with respect to the substrate support surface 111a so that the heat transfer gas discharged from the gas supply ports 111d communicated therewith is directed along the flow of the heat transfer gas. For example, in FIG. 14, the direction in which the heat transfer gas is discharged from the gas supply ports 111d and the direction in which the heat transfer gas is strongly sucked into the gas exhaust port 111e are respectively indicated by arrows. The gas supply ports 111d are formed in line with the substrate support surface 111a along the arc-shaped flow of the heat transfer gas. The supply flow passages 115 are provided at an incline with respect to the substrate support surface 111a so that the heat transfer gas discharged from the gas supply ports 111d communicated therewith is directed along the flow of the arc-shaped heat transfer gas. The gas exhaust port 111e is formed at the position of the hot spot HS or at a position that has passed through the hot spot HS along the arc-shaped flow of the heat transfer gas. The exhaust flow path 117 is inclined with respect to the substrate support surface 111a so that the arcuate flow direction is the direction in which the heat transfer gas is strongly sucked in. As a result, the substrate support 11 shown in FIG. 14 allows a large amount of heat transfer gas to flow toward the hot spot HS on the substrate support surface 111a, so the hot spot HS can be strongly cooled.

The substrate support 11 also has a gas supply port 111d and a supply flow path 115 so that the flow of heat transfer gas passes through areas other than the cold spot. For example, in FIG. 14, the areas other than the three arc-shaped heat transfer gas flows are outside the heat transfer gas flow and have a relatively low heat transfer gas flow rate, resulting in a relatively low cooling capacity, and can be made into a cold spot on the substrate support surface 111a. As a result, the substrate support 11 shown in FIG. 14 has a low heat transfer gas flow rate relative to the cold spot on the substrate support surface 111a, thereby weakening the cooling of the cold spot.

The substrate support 11 can also change the flow rate of the heat transfer gas by providing a straightening plate 111g on the substrate support surface 111a. The substrate support 11 may be provided with a straightening plate 111g so that the flow rate of the heat transfer gas is increased for the hot spot. The substrate support 11 may also be provided with a straightening plate 111g so that the flow rate of the heat transfer gas is decreased for the cold spot. FIG. 15 is a diagram showing another example of the flow of the heat transfer gas on the substrate support surface 111a of the substrate support 11 according to the embodiment. FIG. 15 shows only some of the gas supply ports 111d and straightening plates 111g provided on the substrate support surface 111a. In FIG. 15, the heat transfer gas is discharged from each of the two gas supply ports 111d, and the straightening plate 111g gradually narrows the width through which the heat transfer gas flows. In the portion where the width through which the heat transfer gas flows is narrow, the flow rate of the heat transfer gas increases, and the cooling capacity increases. On the other hand, in areas where the heat transfer gas flows widely, the flow rate of the heat transfer gas decreases, resulting in reduced cooling capacity.

In this way, the substrate support part 11 can partially change the cooling capacity of the substrate support surface 111a by using the gas supply port 111d, the supply flow path 115, the gas exhaust port 111e, the exhaust flow path 117, and the flow straightening plate 111g. The designer of the substrate support part 11 designs the arrangement of the gas supply port 111d, the supply flow path 115, the gas exhaust port 111e, the exhaust flow path 117, and the flow straightening plate 111g according to the desired distribution of the cooling capacity of the substrate support surface 111a.

In addition, the substrate support unit 11 according to the embodiment changes the flow rate of the heat transfer gas in the space 123 by changing the amount of heat transfer gas supplied from the gas supply unit 116 to the supply flow path 115 and the amount of exhaust from the exhaust flow path 117 by the exhaust system 40. The substrate support unit 11 changes the cooling capacity by the heat transfer gas by changing the flow rate of the heat transfer gas in the space 123. The control unit 2 can change the cooling capacity by the heat transfer gas by controlling the gas supply unit 116 and the exhaust system 40. For example, when performing a plasma process with high power, the control unit 2 can increase the cooling capacity by increasing at least one of the amount of heat transfer gas supplied from the gas supply unit 116 to the supply flow path 115 and the amount of heat transfer gas exhausted from the exhaust flow path 117 by the exhaust system 40. In addition, the control unit 2 can control the exhaust system 40 to stop exhausting the heat transfer gas from the exhaust flow path 117, so that the space 123 is filled with the heat transfer gas as in the conventional case.

In addition, in the embodiment, a plasma processing system having a system configuration including the plasma processing apparatus 1 and the control unit 2 has been described as an example. However, this is not limited to this. As described above, a part or all of the control unit 2 may be included in the plasma processing apparatus 1. In other words, a configuration including the plasma processing apparatus 1 and the control unit 2 of the embodiment may be considered as the plasma processing apparatus 1.

As described above, the substrate support part 11 (mounting table) according to the embodiment includes the main body part 111 (mounting part), the band 111f (supporting part), the gas supply port 111d, the supply flow path 115, the gas exhaust port 111e, and the exhaust flow path 117. The substrate support part 11 has a substrate support surface 111a (mounting surface) on which the substrate W is mounted. The band 111f is provided on the substrate support surface 111a along the outer periphery of the substrate W and supports the substrate W. The gas supply port 111d is formed on the substrate support surface 111a and supplies a heat transfer gas to the space 123 between the substrate W and the substrate support surface 111a. The supply flow path 115 is provided in the main body part 111 and supplies a heat transfer gas to the gas supply port 111d. The gas exhaust port 111e is formed on the substrate support surface 111a and exhausts the heat transfer gas in the space 123. The exhaust flow path 117 is provided in the main body 111, and the heat transfer gas exhausted from the gas exhaust port 111e flows through it. In addition, the supply flow path 115 is provided such that at least the gas supply port 111d side is inclined with respect to the substrate support surface 111a. This can increase the cooling capacity of the substrate support part 11.

The gas supply ports 111d are formed at multiple positions on the substrate support surface 111a in a concentric pattern. The supply flow paths 115 are provided in the main body 111 and communicate with the multiple gas supply ports 111d, with each gas supply port 111d side inclined in one circumferential direction of the concentric circle relative to the substrate support surface 111a. This allows the heat transfer gas to flow over the entire substrate support surface 111a, and the entire substrate support surface 111a can be cooled.

In addition, multiple gas exhaust ports 111e are formed in a concentric circle on the substrate support surface 111a with a different radius from the concentric circle of the gas supply port 111d. The exhaust flow path 117 is provided in the main body 111 so as to be connected to each of the multiple gas exhaust ports 111e. This allows the heat transfer gas to circulate within the space 123 for a long period of time, thereby improving the cooling capacity of the substrate support surface 111a.

The main body 111 also has baffles 111g spaced apart from each other and concentrically arranged on the substrate support surface 111a between the gas supply port 111d and the gas exhaust port 111e. This allows the heat transfer gas to circulate stably within the space 123. This allows the entire substrate support surface 111a to be cooled by the heat transfer gas.

The main body 111 is provided with a gas supply port 111d, a supply flow path 115, and a straightening plate 111g so that the flow rate of the heat transfer gas is increased at hot spots where the temperature of the substrate support surface 111a is high, and the flow rate of the heat transfer gas is decreased at cold spots where the temperature of the substrate support surface 111a is low. This makes it possible to prevent temperature unevenness at hot spots and cold spots on the substrate support surface 111a.

In addition, multiple gas supply ports 111d are formed on the substrate support surface 111a along the flow of the heat transfer gas so that a flow of the heat transfer gas occurs toward the hot spot. The supply flow paths 115 are inclined with respect to the substrate support surface 111a so that the heat transfer gas discharged from the gas supply ports 111d connected thereto is directed along the flow of the heat transfer gas. This allows for strong cooling of the hot spot.

The gas supply port 111d and the supply passage 115 are also arranged so that the flow of the heat transfer gas passes through areas other than the cold spot. This can reduce the cooling of the cold spot.

The plasma processing apparatus 1 also has a substrate support section 11 (mounting table), a gas supply section 116, a gas exhaust section (exhaust system 40), and a control section 2. The gas supply section 116 is connected to a supply passage 115 of the substrate support section 11 and supplies a heat transfer gas to the supply passage 115. The gas exhaust section is connected to an exhaust passage 117 of the substrate support section 11 and exhausts the heat transfer gas via the exhaust passage 117. The control section 2 controls at least one of the amount of heat transfer gas supplied from the gas supply section and the amount of heat transfer gas exhausted by the gas exhaust section. This makes it possible to increase the cooling capacity of the substrate support section 11 without increasing the size of the plasma processing apparatus 1.

Although the embodiments have been described above, the embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the claims.

For example, in the above embodiment, a case where plasma processing is performed on a semiconductor wafer as the substrate W is described as an example, but this is not limited to this. The substrate W may be any type.

The substrate support part 11 according to the present disclosure can be applied not only to a capacitively coupled plasma (CCP) device, but also to other substrate processing devices. Other substrate processing devices may be an inductively coupled plasma (ICP) processing device, a plasma processing device using a radial line slot antenna, a helicon wave excited plasma (HWP) device, an electron cyclotron resonance plasma (ECR) device, etc. The substrate support part 11 according to the present disclosure may be used in various substrate processing devices such as a film forming device and a heat treatment device, in addition to a plasma processing device.

The embodiments disclosed herein should be considered as illustrative in all respects and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

Reference Signs List 1 Plasma processing apparatus 2 Control unit 11 Substrate support unit 40 Exhaust system 111 Main body 111a Substrate support surface 111b Annular region 111c Flow path 111d Gas supply port 111e Gas exhaust port 111f Band 111g Flow straightener 111h Dot 114 Chiller unit 115 Supply flow path 116 Gas supply unit 117 Exhaust flow path 123 Space W Substrate

Claims (5)

a mounting section having a mounting surface on which a substrate is placed;
a ring-shaped support portion provided on the mounting surface along an outer periphery of the substrate and supporting the substrate;
a gas supply port formed on the mounting surface for supplying a heat transfer gas to a space between the substrate and the mounting surface;
a supply flow path provided in the mounting portion and configured to supply the heat transfer gas to the gas supply port;
a gas exhaust port formed on the mounting surface for exhausting a heat transfer gas from the space;
an exhaust flow path provided in the mounting portion, through which the heat transfer gas exhausted from the gas exhaust port flows;
Equipped with
The gas supply ports are formed at a plurality of positions concentrically on the mounting surface,
the supply flow passages are provided in the mounting portion and communicate with the plurality of gas supply ports, and the gas supply ports are inclined in one circumferential direction of the concentric circle with respect to the mounting surface ;
the gas exhaust port is formed on the mounting surface in a concentric pattern with a radius different from that of the concentric circle of the gas supply port;
the exhaust flow path is provided in the placement portion and communicates with each of the plurality of gas exhaust ports,
The mounting portion has a flow straightening plate provided on the mounting surface at intervals between the concentric circle of the gas supply port and the concentric circle of the gas exhaust port.
Mounting stand. a mounting section having a mounting surface on which a substrate is placed;
a ring-shaped support portion provided on the mounting surface along an outer periphery of the substrate and supporting the substrate;
a gas supply port formed on the mounting surface for supplying a heat transfer gas to a space between the substrate and the mounting surface;
a supply flow path provided in the mounting portion and configured to supply the heat transfer gas to the gas supply port;
a gas exhaust port formed on the mounting surface for exhausting a heat transfer gas from the space;
an exhaust flow path provided in the mounting portion, through which the heat transfer gas exhausted from the gas exhaust port flows;
Equipped with
the supply flow path is provided such that at least the gas supply port side is inclined with respect to the placement surface ,
The gas supply port, the supply flow path, and the flow straightening plate are provided in the mounting portion so that the flow rate of the heat transfer gas is increased toward a hot spot where the temperature of the mounting surface is high, or the flow rate of the heat transfer gas is decreased toward a cold spot where the temperature of the mounting surface is low.
Mounting stand. the gas supply port is formed in a plurality of ports on the mounting surface along a flow of the heat transfer gas so that a flow of the heat transfer gas is generated toward the hot spot;
The mounting table according to claim 2 , wherein the supply flow passage is provided at an incline with respect to the mounting surface so that the heat transfer gas discharged from the gas supply port connected thereto follows a flow direction of the heat transfer gas. The mounting table according to claim 2 , wherein the gas supply port and the supply passage are provided so that the flow of the heat transfer gas passes through an area other than the cold spot. A mounting table according to any one of claims 1 to 4 ;
a gas supply unit connected to a supply passage of the mounting table and supplying a heat transfer gas to the supply passage;
a gas exhaust unit connected to an exhaust passage of the mounting table and configured to exhaust a heat transfer gas through the exhaust passage;
a control unit that controls at least one of an amount of heat transfer gas supplied from the gas supply unit and an amount of heat transfer gas exhausted by the gas exhaust unit;
A substrate processing apparatus comprising: