Substrate mounting table, substrate processing device, and temperature control method

Abstract

The present invention provides a substrate loading platform, a substrate processing device, and a temperature control method. The temperature distribution of the substrate is controlled to change sharply on the inner and outer sides of the partition wall. The substrate loading platform includes: a base having a loading surface for loading the substrate; an annular support member provided on the base, supporting the substrate along the outer peripheral side of the substrate; an annular partition wall provided on the loading surface, dividing the loading surface into an outer area and an inner area in the radial direction of the substrate loaded on the loading surface; a plurality of protrusions provided on the loading surface at the outer area and the inner area, supporting the substrate in a manner of leaving a gap between the upper end surface of the partition wall and the substrate; an outer flow path provided on the base in a manner connected to the outer area, for supplying heat transfer gas to the space between the substrate and the loading surface; an inner flow path provided on the base in a manner connected to the inner area, for supplying heat transfer gas to flow; and an annular diffusion portion provided on the base, for diffusing the heat transfer gas along the circumferential direction of the partition wall.

Description

Technical Field

[0001] The following disclosure relates to a substrate mounting table, a substrate processing apparatus, and a temperature control method. Background Art

[0002] There is disclosed a substrate mounting table having a structure in which a circular partition wall is provided on a surface on a substrate mounting side so that a heat transfer gas flows under the substrate (Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2012-129547 Summary of the Invention

[0004] Problems to be solved by the invention

[0005] The present disclosure provides a technology capable of controlling the temperature distribution of a substrate so as to change rapidly between the inside and outside of a partition wall.

[0006] Solutions for solving problems

[0007] A substrate mounting table of a technical solution disclosed in the present invention includes: a base, which has a mounting surface for mounting a substrate; an annular supporting member, which is provided on the base and supports the substrate along the outer peripheral side of the substrate; an annular partition wall, which is provided on the mounting surface and divides the mounting surface into an outer area and an inner area in the radial direction of the substrate mounted on the mounting surface; a plurality of protrusions, which are provided on the mounting surface at the outer area and the inner area, and support the substrate in a manner of leaving a gap between the upper end surface of the partition wall and the substrate; an outer flow path, which is provided on the base in a manner connected to the outer area and supplies a heat transfer gas to the space between the substrate and the mounting surface; an inner flow path, which is provided on the base in a manner connected to the inner area and supplies a heat transfer gas to flow; and an annular diffusion portion, which is provided on the base and diffuses the heat transfer gas along the circumferential direction of the partition wall.

[0008] Effects of the Invention

[0009] According to the present disclosure, it is possible to control the temperature distribution of the substrate so as to change rapidly between the inside and the outside of the partition wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram showing the entire substrate processing apparatus according to the first embodiment.

[0011] Figure 2 This is a schematic diagram for explaining the flow of a heat transfer gas in the substrate processing apparatus according to the first embodiment.

[0012] Figure 3 It is a plan view showing the substrate mounting table according to the first embodiment.

[0013] Figure 4 It is a longitudinal sectional view showing the substrate mounting table according to the first embodiment.

[0014] Figure 5 It is a longitudinal sectional view showing an enlarged view of a main portion of the substrate mounting table according to the first embodiment.

[0015] Figure 6 It is a plan view showing a substrate mounting table according to the second embodiment.

[0016] Figure 7 It is a longitudinal sectional view showing a substrate mounting table according to the second embodiment.

[0017] Figure 8 It is a transverse cross-sectional view showing a main part of a substrate mounting table according to a second embodiment.

[0018] Figure 9 It is a cross-sectional view showing an enlarged view of a main portion of a substrate mounting table according to the second embodiment. DETAILED DESCRIPTION

[0019] Hereinafter, the disclosed embodiment will be described in detail based on the accompanying drawings. In addition, this embodiment is not limited. In addition, the various embodiments can be appropriately combined within the scope of the processing contents not contradicting each other. In addition, in this specification and the accompanying drawings, substantially the same structures are marked with the same figure marks, and repeated descriptions are omitted. In addition, in the following description, when a wafer as a substrate is placed on a substrate loading table of a substrate processing device, when viewed from the wafer, the loading table side is referred to as the bottom, and the opposite side is referred to as the top.

[0020] (First embodiment)

[0021] Figure 1 1 is a schematic diagram showing the entire substrate processing apparatus according to the first embodiment. Figure 1 As shown, the substrate processing device 1 includes: a substrate mounting table 5, which mounts the substrate 3; a processing chamber 6, which is provided with the substrate mounting table 5; a processing gas supply part 7, which supplies the processing gas used to process the substrate 3 to the processing chamber 6; a heat transfer gas supply part 8, which supplies heat transfer gas as heat transfer gas to the enclosed space (heat transfer gas space) between the substrate 3 and the substrate mounting table 5; and a processing gas exhaust part 9, which is used to exhaust the processing gas from the processing chamber 6.

[0022] A gas supply pipe 6a connected to the process gas supply unit 7 is provided at the top of the process chamber 6. A shower plate 10 having multiple gas supply holes 10a is provided opposite the gas supply pipe 6a. A gas exhaust pipe 6b connected to the process gas exhaust unit 9 is provided at the bottom of the process chamber 6. Fluorine-containing gas or oxygen-containing gas is used as the process gas, and compounds containing hydrogen, nitrogen, chlorine, etc. may also be added.

[0023] Figure 2 Schematic diagram for explaining the flow of heat transfer gas in the substrate processing apparatus 1 according to the first embodiment. Figure 2 As shown, the substrate mounting table 5 of the substrate processing apparatus 1 is connected to a heat transfer gas supply unit 8. The heat transfer gas supply unit 8 includes a heat transfer gas supply source 11, a vacuum pump 12, and a first pipe 13 and a second pipe 14 that connect the heat transfer gas supply source 11 and the vacuum pump 12 in parallel. An inner heat transfer gas supply unit 8a is provided on the first pipe 13 to supply heat transfer gas to an inner region F2 of the mounting surface 21a of the substrate mounting table 5. An outer heat transfer gas supply unit 8b is provided on the second pipe 14 to supply heat transfer gas to an outer region F1 of the mounting surface 21a of the substrate mounting table 5.

[0024] A gas pressure control unit 15, a gas flow rate control unit 16, and a supply valve V1 are provided in this order on the heat transfer gas supply source 11 side of the first pipe 13 and the second pipe 14. An exhaust valve V3 is provided on the vacuum pump 12 side of each pipe, and an exhaust valve V2 and a throttle 18 are provided in parallel with the exhaust valve V3 via a bypass pipe 17. The first pipe 13 is connected via a connecting pipe 13a to a radially inner region F2 of the mounting surface 21a relative to the substrate 3, which is mounted on the substrate mounting table 5 described later. The second pipe 14 is connected via a connecting pipe 14a to a radially outer region F1 of the mounting surface 21a relative to the substrate 3, which is mounted on the mounting surface 21a of the substrate mounting table 5. The heat transfer gas is used to control the temperature of the substrate 3 mounted on the substrate mounting table 5, and for example, helium or argon can be used.

[0025] The heat transfer gas supply unit 8 configured as described above corrects any temperature distribution that may have occurred inadvertently between the outer and inner regions F1, F2 of the substrate mounting surface 21a of the substrate mounting table 5, thereby creating a temperature distribution between the outer and inner regions F1 and F2. For example, the pressure in the inner region F2 is increased relative to the pressure in the outer region F1. This allows the high-pressure heat transfer gas to remove a relatively large amount of heat from the inner region F2 of the mounting surface 21a, thereby cooling the inner region F2 relative to the outer region F1. To cool the inner region F2 relative to the outer region F1 of the mounting surface 21a, the heat transfer gas supplied from the heat transfer gas supply source 11 through the first pipe 13 and from the connecting pipe 13a to the inner region F2 is set to a high pressure, for example, approximately 50 Torr, while the heat transfer gas supplied from the heat transfer gas supply source 11 through the second pipe 14 and from the connecting pipe 14a to the outer region F1 is set to a low pressure, for example, approximately 40 Torr. Utilizing the pressure difference between the outer region F1 and the inner region F2, the heat transfer gas flows from the high-pressure inner region F2 toward the low-pressure outer region F1 through the gap G between the guide belt 23 and the substrate 3, described later. The heat transfer gas flowing to the low-pressure outer region F1 passes through the second pipe 14 via the connecting pipe 14a, passes through the exhaust valve V2 and the throttle 18 in the second pipe 14, and is discharged by the vacuum pump 12. At this time, the exhaust valve V2 in the second pipe 14 is open, and the exhaust valve V3 is closed. With the inner region F2 of the mounting surface 21a at a high pressure and the outer region F1 at a low pressure, the exhaust valves V2 and V3 in the first pipe 13 are closed, and the heat transfer gas is discharged without passing through the exhaust valves V2 and V3 in the first pipe 13.

[0026] On the other hand, when cooling the outer region F1 of the substrate mounting surface 21a of the substrate mounting table 5 more than the inner region F2, the high-pressure and low-pressure directions are reversed. In this case, the heat transfer gas supplied from the heat transfer gas supply source 11 through the first pipe 13 and from the connecting pipe 13a to the inner region F2 is set to a low pressure, for example, approximately 40 Torr. The heat transfer gas supplied from the heat transfer gas supply source 11 through the second pipe 14 and from the connecting pipe 14a to the outer region F1 is set to a high pressure, for example, approximately 50 Torr. The pressure difference between the outer region F1 and the inner region F2 causes the heat transfer gas to flow from the high-pressure outer region F1 to the low-pressure inner region F2 through the gap G between the guide belt 23 and the substrate 3, described later. The heat transfer gas then flows from the low-pressure inner region F2 side through the connecting pipe 13a, passes through the first pipe 13, and then passes through the exhaust valve V2 and the throttle 18 in the first pipe 13 before being discharged by the vacuum pump 12. At this time, the exhaust valve V2 in the first pipe 13 is open, and the exhaust valve V3 is closed. When the outer region F1 of the placement surface 21a is set to high pressure and the inner region F2 is set to low pressure, the exhaust valves V2 and V3 in the second pipe 14 are closed, and the heat transfer gas is discharged without passing through the exhaust valves V2 and V3 in the second pipe 14.

[0027] In addition, when a fluid flows from a higher-pressure area to a lower-pressure area, a pressure difference inversely proportional to the conductance of the fluid path is generated at each point in the fluid path. When the areas with different conductances of the fluid path are connected in series, the overall pressure difference is distributed in a manner that becomes a ratio of the inverse of the conductance of each area. This principle is applied to the mounting surface 21a of the substrate mounting table 5 in this embodiment, and the fluid flow path from the outer flow path 26 to the inner flow path 27 of the inner area F2 is considered. In this case, the fluid path is considered to be a series connection of the following paths:

[0028] 1) The path from the holes of the outer flow path 26 in the outer region F1 to the guide belt 23;

[0029] 2) a path passing through the gap G between the conductive strip 23 and the substrate 3;

[0030] 3) The path from the guide belt 23 to the holes of the inner flow path 27 in the inner region F2.

[0031] Calculating the conductance of each part becomes:

[0032] 1) 6×10 -6 [m 3 / sec]; 2)1×10 -6 [m 3 / sec]; 3)1×10 -4 [m 3 / sec]. The overall pressure difference is 50 [Torr] - 40 [Torr] = 10 [Torr]. Because this pressure difference is distributed in a ratio that corresponds to the inverse of the conductance, a pressure difference of 8.5 [Torr], equivalent to 85% of the overall pressure difference, is generated between the outer and inner circumferences of the conduction belt 23 in this embodiment. At this time, the flow rate of the heat transfer gas generated by the overall pressure difference of 10 [Torr] is 0.67 [cc] per minute at standard atmospheric pressure.

[0033] For example, the pressure of the heat transfer gas in the inner region F2, separated by the conduction strip 23, is higher than that in the outer region F1. This allows the heat transfer gas to cool the center of the substrate 3 more strongly than the outer periphery. In this embodiment, as an example, the pressure of the heat transfer gas in the inner region F2 is set 10 [Torr] higher than that in the outer region F1. However, this pressure difference and pressure range are not limited and can be varied by configuring the heat transfer gas supply unit 8. This allows the distribution of cooling efficiency on the substrate 3 to be controlled with the conduction strip 23 as the boundary. This allows control of process characteristics that depend on the temperature of the substrate 3, such as the distribution of etching rates on the surface of the substrate 3.

[0034] (Structure of substrate mounting table)

[0035] Figure 3 It is a plan view showing the substrate mounting table 5 according to the first embodiment. Figure 4 is a longitudinal sectional view showing the substrate mounting table 5 according to the first embodiment, taken along Figure 3 The longitudinal section view of line AA in FIG. Figure 3 and Figure 4 As shown, the substrate mounting table 5 includes a base 21 having a mounting surface 21a on which the substrate 3 is mounted; a sealing tape 22 as an annular supporting member that supports the substrate 3 along its outer periphery; and a guide tape 23 as an annular partition wall that divides the mounting surface 21a into an outer region F1 and an inner region F2 in the radial direction of the substrate 3 mounted on the mounting surface 21a (hereinafter referred to as the radial direction of the substrate 3). Furthermore, the substrate mounting table 5 includes a plurality of first protrusions 24 and a plurality of second protrusions 25 that support the substrate 3, leaving a gap G between the upper end surface 23a of the guide tape 23 and the substrate 3.

[0036] The mounting surface 21a of the base 21 is the surface facing the substrate 3 and is the surface on which the substrate 3 is mounted via the plurality of first protrusions 24 on the guide tape 23, the plurality of second protrusions 25 on the mounting surface 21a, and the sealing tape 22. The sealing tape 22 is provided on the mounting surface 21a of the base 21, and is formed at a height of 15 μm from the mounting surface 21a. The guide tape 23 is provided on the mounting surface 21a of the base 21, and is arranged concentrically with the sealing tape 22.

[0037] The height of the guide tape 23 from the mounting surface 21a is 12 μm, ensuring a 3 μm gap G between the substrate 3 supported by the sealing tape 22 and the upper end surface 23a of the guide tape 23. Furthermore, the width of the guide tape 23 in the radial direction of the substrate 3, i.e., in the radial direction of the guide tape 23, is 10 mm. The guide tape 23 is a structural component that acts as a resistance to the flow of the heat transfer gas between the outer region F1 and the inner region F2 of the mounting surface 21a of the base 21.

[0038] The plurality of first protrusions 24 are cylindrically formed and provided on the upper end surface 23a of the conductive strip 23. The height of the plurality of first protrusions 24 from the upper end surface 23a of the conductive strip 23 is 3 μm. The plurality of first protrusions 24 are arranged at predetermined intervals along the circumference of the conductive strip 23, and are arranged in two rows concentrically with respect to the center of the substrate 3. The first protrusions 24 in each row may be alternately staggered relative to the circumference of the conductive strip 23, thereby forming a staggered arrangement.

[0039] The plurality of second protrusions 25 are formed in a cylindrical shape and are provided on the mounting surface 21a in the outer region F1 and the inner region F2. The height of the plurality of second protrusions 25 from the mounting surface 21a is formed to be 15 [μm], which is equal to the height of the sealing tape 22. Figure 3 As shown, the plurality of second protrusions 25 are radially arranged from the center of the placement surface 21 a.

[0040] The substrate 3 placed on the mounting surface 21a is supported by the sealing tape 22, the plurality of first protrusions 24, and the plurality of second protrusions 25. A gap G of 3 μm is maintained between the upper end surface 23a of the conductive tape 23 and the substrate 3 in the vertical direction of the base 21, that is, in the thickness direction of the substrate 3. This gap G prevents the upper end surface 23a of the conductive tape 23 from contacting the substrate 3, thereby suppressing heat transfer between the substrate 3 and the conductive tape 23. This prevents the formation of a temperature singularity, where the temperature of the substrate 3 is locally lowered, directly above the conductive tape 23.

[0041] In addition, the substrate mounting table 5 includes: an outer flow path 26 for supplying a heat transfer gas to the closed space between the substrate 3 and the mounting surface 21a; an inner flow path 27 for supplying a heat transfer gas; and an electrostatic chuck (not shown) for holding the substrate 3 mounted on the mounting surface 21a. In addition, the substrate mounting table 5 includes a refrigerant flow path (not shown) for circulating a refrigerant inside the substrate mounting table 5. The refrigerant flow path is connected to an external chiller (not shown) via a hose for supplying refrigerant. Heat from the plasma generated in the processing chamber 6 during the processing of the substrate 3 flows into the substrate 3 and the substrate mounting table 5, but by circulating the refrigerant inside the substrate mounting table 5, the heat flowing in from the plasma is removed, and the temperature of the substrate 3 being processed and the temperature of the substrate mounting table 5 are controlled to a predetermined temperature.

[0042] The outer flow path 26 is provided on the base 21 so as to communicate with the outer region F1 and penetrates the base 21 in the vertical direction of the base 21. A plurality of the outer flow paths 26 are arranged at predetermined intervals in the circumferential direction of the guide belt 23. For example, six outer flow paths 26 are provided at intervals of 60 degrees around the center of the mounting surface 21a. The outer flow paths 26 are connected to the connecting pipe 14a of the heat transfer gas supply unit 8 (see FIG. 1 ). Figure 2 ).

[0043] The inner flow path 27 is provided on the base 21 so as to communicate with the inner region F2 and penetrates the base 21 in the vertical direction of the base 21. A plurality of inner flow paths 27 are arranged at predetermined intervals in the circumferential direction of the guide belt 23. For example, six inner flow paths 27 are provided at intervals of 60 degrees around the center of the mounting surface 21a. Figure 3 As shown, the position of the inner flow path 27 in the circumferential direction of the guide belt 23 is the same as that of the outer flow path 26. The inner flow path 27 is connected to the connecting pipe 13a of the heat transfer gas supply unit 8 (see Figure 2 ).

[0044] Although not shown, an electrostatic chuck includes an insulator and electrodes and is disposed on the base 21. The electrostatic chuck holds the substrate 3 placed on the mounting surface 21a by applying a voltage to the electrodes. The chuck used to hold the substrate 3 on the substrate mounting table 5 is not limited to an electrostatic chuck; a chuck that mechanically holds the substrate 3 may also be used.

[0045] (Structure of the Diffuser)

[0046] Moreover, if Figure 3 and Figure 4As shown, the substrate mounting table 5 includes an annular diffuser 28 that diffuses the heat transfer gas along the circumferential direction of the guide belt 23. The diffuser 28 is a recessed portion opening into the mounting surface 21a of the base 21, and has a square groove-like cross-section. The diffuser 28 includes an outer diffuser 28a communicating with the outer region F1 and an inner diffuser 28b communicating with the inner region F2.

[0047] The outer diffuser 28a diffuses the heat transfer gas flowing from the outer flow path 26 into the outer region F1 along the outer circumference of the guide belt 23. The inner diffuser 28b diffuses the heat transfer gas flowing from the inner flow path 27 into the inner region F2 along the inner circumference of the guide belt 23.

[0048] Figure 5 1 is an enlarged longitudinal sectional view showing the main parts of the substrate mounting table 5 according to the first embodiment. Figure 4 and Figure 5 As shown, the outer diffuser 28a includes: a first outer diffuser 28a1, which opens on the mounting surface 21a and is provided along the outer peripheral surface of the guide belt 23; and a second outer diffuser 28a2, which opens on the mounting surface 21a and is provided at the end of the outer flow path 26. Figure 3 As shown, the second outer diffuser 28 a 2 is arranged at a distance from the inner peripheral surface of the sealing band 22 in the radial direction of the substrate 3 .

[0049] like Figure 4 and Figure 5 As shown, the inner diffuser 28b includes: a first inner diffuser 28b1 which opens on the mounting surface 21a and is provided along the inner circumference of the guide belt 23; and a second inner diffuser 28b2 which opens on the mounting surface 21a and is provided at the end of the inner flow path 27. Figure 3 As shown, the second inner diffusion portion 28 b 2 is arranged at a position substantially midway between the center of the mounting surface 21 a and the inner peripheral surface of the guide belt 23 in the radial direction of the substrate 3 .

[0050] The base 21 is provided with a connecting passage 29a extending radially relative to the substrate 3 placed on the mounting surface 21a. This connecting passage 29a connects the first outer diffuser 28a1 and the second outer diffuser 28a2. The connecting passage 29a is formed as a recessed portion opening into the mounting surface 21a. The heat transfer gas flowing along the first and second outer diffusers 28a1, 28a2 passes through the connecting passage 29a and flows into the first and second outer diffusers 28a1, 28a2. Because the first and second outer diffusers 28a1, 28a2, and connecting passage 29a are arranged to surround the outer region F1, the conductance of the outer region F1 as a whole is improved, thereby uniformizing the pressure within the outer region F1.

[0051] Furthermore, the base 21 is provided with a connecting passage 29b extending radially along the substrate 3 placed on the mounting surface 21a. This connecting passage 29b connects the first inner diffuser 28b1 and the second inner diffuser 28b2. The connecting passage 29b is formed as a recessed portion opening into the mounting surface 21a, with a square groove-like cross-section. Heat transfer gas flowing along the first and second inner diffusers 28b1, 28b2 passes through the connecting passage 29b and flows into the first and second inner diffusers 28b1, 28b2. Because the first and second inner diffusers 28b1, 28b2, and connecting passage 29b are arranged to surround the inner region F2, the conductance of the entire inner region F2 is improved, thereby uniformizing the pressure within the inner region F2.

[0052] In addition, if Figure 3 As shown, a plurality of third protrusions 31 for supporting the substrate 3 are provided on the bottom surfaces of the connecting passages 29a and 29b. The height of the plurality of third protrusions 31 from the bottom surfaces of the connecting passages 29a and 29b is formed to be 65 μm, and the top ends of the third protrusions 31 are aligned with the upper end surface of the sealing tape 22, the top ends of the first protrusions 24, and the top ends of the second protrusions 25. The substrate mounting table 5 is not limited to a structure having the third protrusions 31.

[0053] The cross-sectional shape of the diffusion portion 28 is not limited to a square groove; for example, it may be formed into a V-groove shape or a tapered cross-sectional shape having a width in the radial direction of the substrate 3 that gradually expands toward the mounting surface 21a. Furthermore, the connection passages 29a and 29b are formed to open on the mounting surface 21a, but may also be formed within the internal space of the base portion 21.

[0054] In addition, if Figure 3 and Figure 4 As shown, a flange-shaped fixing portion 30 is formed on the outer periphery of the base portion 21 , and a plurality of fixing holes 30 a for passing fixing members such as bolts (not shown) are provided at intervals in the circumferential direction of the fixing portion 30 .

[0055] (Diffusion effect of the diffusion part)

[0056] As described above, the first outer diffuser 28a1, the second outer diffuser 28a2, and the connecting passage 29a enhance the conductance within the outer region F1. Consequently, the pressure gradient of the heat transfer gas within the outer region F1 is suppressed, and the pressure of the heat transfer gas within the outer region F1 is uniform. Similarly, the first inner diffuser 28b1, the second inner diffuser 28b2, and the connecting passage 29b enhance the conductance within the inner region F2. Consequently, the pressure gradient of the heat transfer gas within the inner region F2 is suppressed, and the pressure of the heat transfer gas within the inner region F2 is uniform.

[0057] Furthermore, due to manufacturing errors in the substrate mounting table 5, wear over time, and other factors, the height of the upper end surface 23a of the guide tape 23 may vary along the circumference of the guide tape 23. In this case, the heat transfer gas is more likely to flow in from locations along the circumference of the guide tape 23 where the gap G between the substrate 3 and the upper end surface 23a of the guide tape 23 is relatively large (where the height of the guide tape 23 is relatively low). Consequently, a pressure gradient for the heat transfer gas may also be generated along the circumference of the guide tape 23 in areas outside the guide tape 23 (within the outer region F1 and the inner region F2). Consequently, when a pressure gradient is generated along the circumference of the guide tape 23 toward locations where the heat transfer gas is more likely to flow in, the pressure distribution becomes asymmetric with respect to the central axis of the substrate 3, resulting in an asymmetric distribution of etching characteristics.

[0058] In this case, the heat transfer gas that partially flows in from a portion of the circumferential direction of the guide belt 23 also flows along the circumferential direction of the guide belt 23 by passing through the first outer diffuser 28a1 along the outer circumferential surface of the guide belt 23 and the first inner diffuser 28b1 along the inner circumferential surface of the guide belt 23. Therefore, even if flow concentration occurs on the guide belt 23, the generation of a pressure gradient of the heat transfer gas in the circumferential direction of the guide belt 23 in portions other than the guide belt 23 can be suppressed. Furthermore, in this case, the heat transfer gas that partially flows in from a portion of the circumferential direction of the guide belt 23 also flows along the circumferential direction of the guide belt 23 by passing through the second outer diffuser 28a2 and the second inner diffuser 28b2. Consequently, the generation of a pressure gradient of the heat transfer gas in the circumferential direction of the guide belt 23 is further suppressed.

[0059] (Temperature control method)

[0060] The temperature control method involved in the embodiment has the following contents: the substrate 3 is supported on an annular sealing belt 22 along the outer peripheral side of the substrate 3, and the annular sealing belt 22 is provided on the base 21, and the base 21 has a loading surface 21a for loading the substrate 3; the loading surface 21a is divided into an outer area F1 and an inner area F2 in the radial direction of the substrate 3 loaded on the loading surface 21a by using an annular guide belt 23 provided on the loading surface 21a, and the substrate 3 is supported by using a first protrusion 24 provided on the guide belt 23 in a manner that a gap G is left between the upper end surface 23a of the guide belt 23 and the substrate 3. Moreover, the temperature control method includes the following contents: utilizing the annular diffusion portion 28 provided on the base 21, the heat transfer gas supplied to the space between the substrate 3 and the mounting surface 21a via the outer flow path 26 and the inner flow path 27 is diffused along the circumference of the guide belt 23, and the outer flow path 26 and the inner flow path 27 are respectively provided on the base 21 in a manner connected to the outer area F1 and the inner area F2.

[0061] (Effects of the First Embodiment)

[0062] The substrate mounting table 5 according to the first embodiment includes a sealing tape 22 that supports the substrate 3; a guide tape 23 that partitions the mounting surface 21a into an outer region F1 and an inner region F2; a plurality of second protrusions 25 that support the substrate 3 with a gap G between the guide tape 23 and the substrate 3; outer and inner flow paths 26 and 27 through which a heat transfer gas flows; and an annular diffuser 28 that diffuses the heat transfer gas along the circumference of the guide tape 23. The diffuser 28 smoothly diffuses the heat transfer gas along the circumference of the guide tape 23, thereby increasing the conductance between the outer region F1 and the inner region F2, resulting in a relatively large conductance ratio compared to the guide tape 23. This ensures a high pressure difference between the outer region F1 and the inner region F2, which are partitioned by the guide tape 23. Consequently, the temperature distribution (pressure distribution) of the substrate 3, whose temperature is controlled by the heat transfer gas, can be controlled so that the temperature distribution changes sharply between the outer region F1 and the inner region F2. Therefore, it is possible to improve the accuracy of temperature control of the substrate 3 using the heat transfer gas. In particular, when controlling the process characteristics of the substrate 3, it is sometimes necessary to control the local temperature distribution of the substrate 3. Therefore, since a sharp pressure difference can be applied at the conduction band boundary, the range of process characteristic control can be expanded.

[0063] Furthermore, the diffuser 28 of the substrate mounting table 5 according to the first embodiment includes an outer diffuser 28a, which is provided in communication with the outer region F1 and diffuses the heat transfer gas circumferentially along the outer periphery of the conduction belt 23; and an inner diffuser 28b, which is provided in communication with the inner region F2 and diffuses the heat transfer gas circumferentially along the inner periphery of the conduction belt 23. When the heat transfer gas, having passed through the gap G between the conduction belt 23 and the substrate 3, flows largely from a portion of the circumference of the conduction belt 23, either the outer diffuser 28a or the inner diffuser 28b can be used to cause the heat transfer gas to flow circumferentially along the conduction belt 23, regardless of whether the outer region F1 or the inner region F2 is at a low pressure. Consequently, the generation of a pressure gradient of the heat transfer gas between the outer region F1 and the inner region F2 can be suppressed.

[0064] Furthermore, the outer diffuser 28a of the substrate mounting table 5 according to the first embodiment includes a first outer diffuser 28a1, which opens on the mounting surface 21a and is provided along the outer circumference of the guide belt 23; and a second outer diffuser 28a2, which opens on the mounting surface 21a and is provided at the end of the outer flow path 26. Thus, the first and second outer diffusers 28a1, 28a2 enable the heat transfer gas in the outer region F1 to be smoothly diffused along the circumference of the guide belt 23. This further uniformizes the pressure of the heat transfer gas in the outer region F1, improving the accuracy of controlling the temperature distribution of the substrate 3. Furthermore, since the first and second outer diffusers 28a1, 28a2 open on the mounting surface 21a, the workability of the first and second outer diffusers 28a1, 28a2 can be ensured.

[0065] Furthermore, the inner diffuser 28b of the substrate mounting table 5 according to the first embodiment includes a first inner diffuser 28b1, which opens on the mounting surface 21a and is disposed along the inner circumference of the guide belt 23; and a second inner diffuser 28b2, which opens on the mounting surface 21a and is disposed at the end of the inner flow path 27. Thus, the first and second inner diffusers 28b1, 28b2 enable the heat transfer gas within the inner region F2 to diffuse smoothly along the circumference of the guide belt 23. This further uniformizes the pressure of the heat transfer gas within the inner region F2, improving the accuracy of controlling the temperature distribution of the substrate 3. Furthermore, since the first and second inner diffusers 28b1, 28b2 open on the mounting surface 21a, the workability of the first and second inner diffusers 28b1, 28b2 can be ensured.

[0066] Furthermore, the base portion 21 of the substrate mounting table 5 according to the first embodiment is provided with a connecting passage 29a that connects the first outer diffuser 28a1 and the second outer diffuser 28a2. This allows the heat transfer gas flowing through the first outer diffuser 28a1 and the second outer diffuser 28a2 within the outer region F1 to flow back and forth between the first and second outer diffusers 28a1, 28a2 via the connecting passage 29a. This further uniformizes the pressure of the heat transfer gas within the outer region F1, improving the accuracy of controlling the temperature distribution of the substrate 3.

[0067] Furthermore, the base portion 21 of the substrate mounting table 5 according to the first embodiment is provided with a connecting passage 29b that connects the first inner diffuser 28b1 and the second inner diffuser 28b2. This allows the heat transfer gas flowing through the first inner diffuser 28b1 and the second inner diffuser 28b2 within the inner region F2 to flow back and forth between the first inner diffuser 28b1 and the second inner diffuser 28b2 via the connecting passage 29b. This further uniformizes the pressure of the heat transfer gas within the inner region F2, improving the accuracy of controlling the temperature distribution of the substrate 3.

[0068] Furthermore, in the substrate mounting table 5 according to the first embodiment, a plurality of first protrusions 24 are provided on the guide belt 23. These first protrusions 24 support the substrate 3 while leaving a gap G between the guide belt 23 and the substrate 3. By supporting the substrate 3 with the plurality of first protrusions 24 in this manner, the stability of the support state of the substrate 3 mounted on the mounting surface 21 a can be improved.

[0069] Furthermore, the first embodiment is not limited to including both the outer diffuser 28a and the inner diffuser 28b. The diffuser 28 may be provided only on the side of the outer region F1 or the inner region F2 where the pressure is relatively low (the temperature is high). For example, in the case of a substrate mounting table 5 that is controlled to have a temperature distribution where the inner region F2 is at a low temperature and the outer region F1 is at a high temperature, by only including the outer diffuser 28a, the inner diffuser 28b can be omitted, simplifying the structure and reducing the manufacturing cost of the substrate mounting table 5.

[0070] (Second embodiment)

[0071] Figure 6 It is a plan view showing a substrate mounting table according to the second embodiment. Figure 7 is a longitudinal sectional view showing a substrate mounting table according to the second embodiment, taken along Figure 6 The second embodiment is different from the diffuser 28 of the first embodiment in that the diffuser 28 is provided inside the base 21 .

[0072] like Figure 6 and Figure 7 As shown, the substrate mounting table 35 includes an annular diffuser 38 that diffuses the heat transfer gas along the circumferential direction of the guide belt 23. The diffuser 38 is provided within the interior space of the base 21 and has a rectangular cross-sectional shape. For example, the diffuser 38 may also have a circular cross-sectional shape. The diffuser 38 includes an outer diffuser 38a, which communicates with the outer region F1, and an inner diffuser 38b, which communicates with the inner region F2.

[0073] (Structure of the Diffuser)

[0074] Figure 8 This is a cross-sectional view showing the main parts of the substrate mounting table according to the second embodiment, taken along Figure 7 Cross-sectional view of line CC in. Figure 9 1 is an enlarged cross-sectional view showing the main parts of the substrate mounting table according to the second embodiment. Figure 7 and Figure 9 As shown, the outer diffuser 38a is provided inside the base 21 so as to communicate with the outer flow path 26. In addition, the inner diffuser 38b is provided inside the base 21 so as to communicate with the inner flow path 27.

[0075] like Figure 7 and Figure 8 As shown, the outer flow path 26 has a main flow path 26a extending from the outer diffuser 38a to the bottom surface of the base 21, and the main flow path 26a is connected to the connecting pipe 14a of the heat transfer gas supply part 8 (see Figure 2 The inner flow path 27 has a main flow path 27a extending from the inner diffuser 38b to the bottom surface of the base 21. The main flow path 27a is connected to the connecting pipe 13a of the heat transfer gas supply unit 8 (see Figure 2 A main flow path 26 a of the outer flow path 26 is provided at a predetermined position in the circumferential direction of the guide belt 23 . Similarly, a main flow path 27 a of the inner flow path 27 is provided at a predetermined position in the circumferential direction of the guide belt 23 .

[0076] Furthermore, the outer flow path 26 includes, in the radial direction of the substrate 3 placed on the mounting surface 21a, an outer branch flow path 26b extending from the outer circumference of the outer diffuser 38a to the mounting surface 21a, and an inner branch flow path 26c extending from the inner circumference of the outer diffuser 38a to the mounting surface 21a. The inner branch flow path 26c of the outer flow path 26 is disposed adjacent to the outer circumference of the guide strip 23 and is configured to smoothly guide the heat transfer gas flowing from the upper end surface 23a of the guide strip 23 into the outer region F1 through the inner branch flow path 26c into the outer diffuser 38a. Consequently, the heat transfer gas flowing from the inner branch flow path 26c into the outer diffuser 38a flows smoothly along the circumference of the guide strip 23 through the outer diffuser 38a.

[0077] Furthermore, the inner flow path 27 includes, in the radial direction of the substrate 3 placed on the mounting surface 21a, an outer branch flow path 27b extending from the outer circumference of the inner diffuser 38b to the mounting surface 21a, and an inner branch flow path 27c extending from the inner circumference of the inner diffuser 38b to the mounting surface 21a. The outer branch flow path 27b of the inner flow path 27 is disposed adjacent to the inner circumference of the guide strip 23. It guides the heat transfer gas flowing from the upper end surface 23a of the guide strip 23 into the inner region F2 smoothly through the outer branch flow path 27b into the inner diffuser 38b. Consequently, the heat transfer gas flowing from the outer branch flow path 27b into the inner diffuser 38b flows smoothly along the circumference of the guide strip 23 by passing through the inner diffuser 38b.

[0078] (Diffusion effect of the diffusion part)

[0079] In the second embodiment, similar to the diffuser 28 of the first embodiment, an outer diffuser 38a is formed along the circumference of the guide strip 23. Therefore, the heat transfer gas supplied to the outer region F1 through the outer flow path 26 passes through the outer diffuser 38a and flows in the circumferential direction of the guide strip 23, smoothly flowing through the outer branch flow path 26b and the inner branch flow path 26c within the outer region F1. This suppresses the generation of a pressure gradient for the heat transfer gas within the outer region F1, and the pressure of the heat transfer gas within the outer region F1 is uniform. Similarly, because an inner diffuser 38b is formed along the circumference of the guide strip 23, the heat transfer gas supplied to the inner region F2 through the inner flow path 27 passes through the inner diffuser 38b and flows in the circumferential direction of the guide strip 23, smoothly flowing through the outer branch flow path 27b and the inner branch flow path 27c within the inner region F2. Therefore, the pressure gradient of the heat transfer gas in the inner region F2 is suppressed from occurring, and the pressure of the heat transfer gas in the inner region F2 is made uniform.

[0080] Furthermore, even if the height of the guide belt 23 varies in the circumferential direction of the guide belt 23, the heat transfer gas that partially flows in from a portion of the circumferential direction of the guide belt 23 passes through the outer diffuser 38a communicating with the outer region F1 and the inner diffuser 38b communicating with the inner region F2, and flows along the circumferential direction of the guide belt 23. Consequently, the generation of a pressure gradient of the heat transfer gas in the circumferential direction of the guide belt 23 is suppressed, and the pressure of the heat transfer gas in the outer region F1 and the inner region F2 is made uniform.

[0081] (Effects of the Second Embodiment)

[0082] Because the substrate mounting table 35 according to the second embodiment includes the diffusion portion 38, similarly to the first embodiment, a large pressure difference can be maintained between the outer region F1 and the inner region F2 separated by the guide strip 23. Therefore, the temperature distribution of the substrate 3 can be controlled to change rapidly between the outer region F1 and the inner region F2. Consequently, the accuracy of temperature control of the substrate 3 using the heat transfer gas can be improved.

[0083] Furthermore, since the diffusion portion 38 of the substrate mounting table 35 does not open onto the mounting surface 21a but is instead disposed within the base 21, the diffusion portion 38 can be prevented from affecting the process characteristics during processing of the substrate 3 by the process gas. In the case of a recessed portion opening onto the mounting surface 21a, the width and depth of the recessed portion may affect the process characteristics during processing of the substrate 3. However, the second embodiment is advantageous in that the pressure gradients within the outer region F1 and the inner region F2 can be suppressed without affecting the mounting surface 21a.

[0084] Furthermore, the substrate mounting table 35 can ensure a greater amount of space for functioning as the diffusion portion 38 than the diffusion portion 28 in the first embodiment, thereby improving the flowability of the heat transfer gas in the circumferential direction of the guide belt 23. Therefore, even if, for example, manufacturing variations in the guide belt 23 cause the heat transfer gas to flow locally between the outer region F1 and the inner region F2 from a portion of the circumferential direction of the guide belt 23, the generation of a heat transfer gas pressure gradient in the circumferential direction of the guide belt 23 can be suppressed, thereby making the heat transfer gas pressure in the outer region F1 and the inner region F2 uniform.

[0085] Furthermore, while the substrate mounting table 5 according to the first and second embodiments includes a single guide strip 23, it may also include multiple guide strips. In this case, the multiple guide strips are arranged concentrically with respect to the center of the mounting surface 21a. Furthermore, the first and second embodiments may be combined as needed. For example, the substrate mounting table may include the outer diffuser 38a and inner diffuser 38b of the second embodiment, and the second outer diffuser 28a2 and second inner diffuser 28b2 of the first embodiment.

Claims

1. A substrate mounting table, wherein: The substrate mounting table includes: a base having a placement surface on which a substrate is placed; an annular supporting member provided on the base portion and supporting the substrate along an outer circumference of the substrate; an annular partition wall provided on the mounting surface and dividing the mounting surface into an outer area and an inner area in a radial direction of the substrate mounted on the mounting surface; a plurality of protrusions provided on the placement surface in the outer region and the inner region, and supporting the substrate with a gap between the upper end surface of the partition wall and the substrate; an outer flow path provided on the base portion so as to communicate with the outer region and through which a heat transfer gas supplied to the space between the substrate and the mounting surface flows; an inner flow path provided at the base portion in communication with the inner region and allowing the heat transfer gas to flow; and An annular diffuser is provided on the base portion and diffuses the heat transfer gas along the circumferential direction of the partition wall.

2. The substrate mounting table according to claim 1, wherein The diffuser includes an outer diffuser connected to the outer region to diffuse the heat transfer gas circumferentially along the outer peripheral side of the partition wall; and an inner diffuser connected to the inner region to diffuse the heat transfer gas circumferentially along the inner peripheral side of the partition wall.

3. The substrate mounting table according to claim 2, wherein: The outer diffuser includes a first outer diffuser opening at the placement surface and provided along the outer peripheral surface of the partition wall; and a second outer diffuser opening at the placement surface and provided at an end of the outer flow path.

4. The substrate mounting table according to claim 2, wherein: The inner diffuser includes a first inner diffuser that opens at the placement surface and is provided along the inner peripheral surface of the partition wall; and a second inner diffuser that opens at the placement surface and is provided at an end of the inner flow path.

5. The substrate mounting table according to claim 3, wherein The base portion is provided with a connecting passage that connects the first outer diffuser portion and the second outer diffuser portion.

6. The substrate mounting table according to claim 4, wherein: The base portion is provided with a connecting passage that connects the first inner diffuser portion and the second inner diffuser portion.

7. The substrate mounting table according to claim 1, wherein The diffuser is provided inside the base so as to communicate with either the outer flow path or the inner flow path. The one flow path includes an outer branch flow path extending from the outer peripheral side of the diffuser to the placement surface, and an inner branch flow path extending from the inner peripheral side of the diffuser to the placement surface.

8. The substrate mounting table according to any one of claims 1 to 7, wherein The partition wall is provided with a plurality of protrusions that support the substrate with a gap formed between an upper end surface of the partition wall and the substrate.

9. A substrate processing device, wherein: The substrate processing device comprises: A substrate mounting table, which is the substrate mounting table according to any one of claims 1 to 8; a processing chamber provided with the substrate mounting table; a processing gas supply unit for supplying a processing gas for processing the substrate into the processing chamber; and A heat transfer gas supply unit supplies the heat transfer gas.

10. A temperature control method, wherein: The temperature control method has the following contents: The substrate is supported along the outer periphery of the substrate by an annular support member, wherein the annular support member is provided on a base having a placement surface on which the substrate is placed; An annular partition wall provided on the mounting surface is used to divide the mounting surface into an outer area and an inner area in a radial direction of the substrate mounted on the mounting surface, and a plurality of protrusions provided on the mounting surface at the outer area and the inner area support the substrate with a gap between an upper end surface of the partition wall and the substrate; as well as The heat transfer gas supplied to the space between the substrate and the mounting surface via the outer flow path and the inner flow path is diffused along the circumference of the partition wall by utilizing the annular diffusion portion provided on the base. The outer flow path and the inner flow path are provided on the base in a manner connected to the outer area and the inner area respectively.

11. The temperature control method according to claim 10, wherein: The temperature control method has the following contents: The heat transfer gas is diffused along the circumferential direction of the partition wall by the diffusion portion that opens at the placement surface and is provided along the outer peripheral surface of the partition wall.

12. The temperature control method according to claim 10, wherein: The temperature control method has the following contents: the heat transfer gas is diffused along the circumferential direction of the partition wall by the diffuser provided inside the base portion so as to communicate with either the outer flow path or the inner flow path; as well as The heat transfer gas is supplied to the space between the substrate and the mounting surface by using the flow path including the outer branch flow path extending from the outer periphery of the diffuser to the mounting surface and the inner branch flow path extending from the inner periphery of the diffuser to the mounting surface.

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