Pedestal stem cooling system

Abstract

This invention provides a pedestal stem cooling system that effectively cools the pedestal stem in situations where the pedestal may reach temperatures exceeding 600°C.

Description

Technical Field

[0001] Related Applications The PCT application is filed herewith simultaneously with this specification as part of this application. Each application to which this application claims benefit or priority and which is identified in the PCT application filed herewith is hereby incorporated by reference in its entirety for all purposes.

Background Art

[0002] Semiconductor manufacturing processes are often carried out in a chamber in which one or more semiconductor wafers are supported on a pedestal during wafer processing operations. Such pedestals may be used with a corresponding gas distribution system, such as a showerhead, that distributes process gas across the entire exposed surface of the semiconductor wafer supported by the pedestal. Pedestals are typically relatively large platform-like structures that are larger in size than the wafers they are designed to support. Pedestals may include various systems that can be used during various stages of semiconductor wafer processing and / or handling. For example, a pedestal may include a heater, a cooling system, a chuck (vacuum and / or electrostatic) for clamping the wafer in place, lift pin holes through which lift pins can be extended to lift the wafer from the upper surface of the pedestal, electrodes for supplying radio frequency energy that can be used to generate plasma within the processing chamber, temperature sensors, and the like.

[0003] Pedestals are typically supported within a semiconductor processing chamber by a stem, which is generally a smaller columnar structure that extends outwardly from the underside of the pedestal. In some examples, the stem may extend vertically downward and pass through an opening in the bottom wall of the processing chamber. In other examples, the stem may extend vertically downward for a certain distance and then extend radially outward so as to pass through an opening in the side wall of the processing chamber.

[0004] Pedestals are often designed to be movable along a vertical axis, for example, to allow them to be moved between different raised sections within the processing chamber. For example, the stem supporting the pedestal in the processing chamber may be mounted on a linear actuator or other vertical lift mechanism that can be operated to move the stem and pedestal vertically. This allows, for example, the distance between the showerhead and the wafer supported by the pedestal to be adjusted while the pedestal is descending relative to the wafer, or the wafer to be placed on a lift pin, thereby creating a gap beneath the wafer into which an end effector can be inserted and then moved upward to lift the wafer off the lift pin and remove it from the processing chamber.

[0005] This specification describes a system for more efficiently removing heat that may be generated or conducted within the pedestal and / or stem. [Overview of the project] [Means for solving the problem]

[0006] Details of one or more implementations of the subject matter described herein are given in the accompanying drawings and the following description. Other features, embodiments, and advantages will become apparent from the description, drawings, and claims.

[0007] In some implementations, a system may be provided that includes a pedestal having a first surface configured to support a semiconductor wafer during semiconductor processing operations, and a second surface opposite the first surface. The system may further include a stem having a first end connected to the pedestal and a second end located further from the second surface than the first end of the stem. The system also includes a support structure connected to the second end of the stem, having at least one first surface axially bonded to a second surface located at or near the second end of the stem, and a first cooling passage segment having at least one first surface interposed between the first cooling passage segment and the stem.

[0008] In some implementations, at least one of at least one first surface and a second surface may include a seal groove, and the system may further include a seal located within the seal groove and compressed between at least one first surface and a second surface.

[0009] In some implementations, the support structure may include a seal collar connected to a bellow seal, the bellow seal may enclose at least a portion of the stem, and the bellow seal may be made of metal.

[0010] In some such implementations, the support structure may further include a polymer layer interposed between at least a portion of the seal collar and the first cooling passage segment. In such implementations, the support structure may also include a retaining collar having a first portion that abuts the second end of the stem and a second portion connected to the first portion. The first cooling passage segment may be positioned between the second portion of the retaining collar and the second surface of the stem.

[0011] In some implementations, the first cooling passage segment may be a tube extending around a first portion of the retaining collar, and the support structure may be configured such that the first portion of the retaining collar is compressed in contact with a second end of the stem, and at least a portion of the polymer layer adjacent to the seal collar is in a compressed state.

[0012] In some implementations, the polymer layer may have a first surface facing the stem and a second surface facing the opposite direction from the first surface. Furthermore, the polymer layer may be sized such that, when the polymer layer is in an uncompressed state and both the first and second surfaces of the polymer layer are in contact with other parts of the support structure, the first portion of the retaining collar does not come into contact with the second end of the stem.

[0013] In some implementations, at least one first surface of the support structure and a second surface of the stem may define a contact region where at least one first surface and the second surface overlap each other when viewed along the central axis of the stem extending between the first end and the second end of the stem. In such implementations, the first cooling passage segment may be at least partially located within a reference volume whose boundary is defined by the inner and outer edges of the contact region, and which extends along the central axis of the stem.

[0014] In some implementations having a tube, the tube may follow a path around a first portion of a retaining collar, the second portion of the retaining collar may have a first concave region extending around the first portion of the retaining collar, and the tube may be positioned within and in contact with the first concave region.

[0015] In some such implementations, the support structure may further include a load distributor interposed at least partially between the first cooling passage segment and the polymer layer. The load distributor may also be interposed at least partially between the second portion of the retaining collar and the polymer layer. In such implementations, the cooling passage segment may be interposed between at least a portion of the second portion of the retaining collar and a portion of the load distributor.

[0016] In some such implementations, the load distributor may have an opening through which a first portion of the retaining collar extends, the load distributor may have a second concave region extending around the opening, and the tube may be positioned within and in contact with the second concave region.

[0017] In some implementations, the path can be an arc-shaped path.

[0018] In some implementations, a gap may exist between the load distributor and the second portion of the retaining collar when the first cooling passage segment is in contact with both the load distributor and the retaining collar but is not compressed.

[0019] In some implementations, the second end of the stem may have a first inner circumference, the first inner circumference having a plurality of first lobes extending radially inward from its outermost portion.

[0020] In some such implementations, the retaining collar may have a second inner circumference, which has a plurality of second lobes extending radially inward from its outermost portion, and the first and second lobes may be aligned with respect to each other in the rotational direction.

[0021] In some implementations, the system may further include a plurality of first screw fasteners, each first screw fastener being screwed into a corresponding threaded hole in one of the first lobes through a corresponding through-hole in one of the second lobes.

[0022] In some implementations, the first lobe may terminate at the second surface, and the second lobe may terminate in the same plane as at least one first surface.

[0023] In some implementations, the system may further include a plurality of elongated structures extending through the stem from the second face of the pedestal. Each elongated structure may have a portion disposed between two of the first lobes adjacent to each other.

[0024] In some implementations, the plurality of elongated structures may include at least a coolant supply passage and a coolant return passage.

[0025] In some implementations, the plurality of elongated structures may include at least a first electrical conductor and a second electrical conductor.

[0026] In some implementations, the system may further include a central elongated structure extending through the center of the stem from the second face of the pedestal.

[0027] In some implementations, the central elongated structure may be a sensor cable.

[0028] In some implementations, the system may further include a second cooling passage segment and a third cooling passage segment, and the first cooling passage segment may be fluidly interposed between the second cooling passage segment and the third cooling passage segment. The first cooling passage segment, the second cooling passage segment, and the third cooling passage segment may be connected to each other, and the second cooling passage segment and the third cooling passage segment may each have a respective portion spatially fixed to the first portion of the support structure. The retaining collar may be connected to one or more other components of the support structure such that the respective portions of the second cooling passage segment and the third cooling passage segment do not need to move relative to the first portion of the support structure and the retaining collar is removable from the remaining portion of the support structure.

[0029] In some implementations, the retention collar may include two halves.

[0030] In some implementations, the support structure may further include a support collar interposed between a portion of the seal collar and a portion of the retention collar, the support collar having a plurality of attachment features disposed around its outer periphery.

[0031] In some implementations, the system may further include a processing chamber and a showerhead. The pedestal may be disposed within the interior volume of the processing chamber, the first end of the stem may be disposed within the interior volume of the processing chamber, and the second end of the stem may be disposed outside the processing chamber.

[0032] In some implementations, the system may further include a hexapod mechanism having a fixed base, a movable base, and six linear actuators. The support structure may be attached to the movable base, the fixed base may be attached to the processing chamber, the first end of each linear actuator may be connected to the fixed base, and the second end of each linear actuator may be connected to the movable base. In some implementations, the system may further include a vertical lift mechanism having a base portion and a movable portion. The support structure may be spatially fixed relative to the movable portion, and the vertical lift mechanism may include one or more actuators configured to move the movable portion relative to the base portion in response to one or more input signals.

[0033] The following description is made with reference to the following figures, which are not intended to limit the scope and are provided merely to facilitate the following description.

Brief Description of the Drawings

[0034] [Figure 1] FIG. 1 is a perspective view showing an exemplary apparatus including a pedestal, a stem, and a support structure. [Figure 2] FIG. 2 shows the same exemplary apparatus, but with its various components shown in a disassembled state. [Figure 3] This is a cross-sectional view showing the apparatus in Figure 1. [Figure 4] This is a detailed view showing the area circled in Figure 3. [Figure 5] This is the same cross-sectional detail view as Figure 4, except that the stem is partially withdrawn from the support structure. [Figure 6] This is an exploded perspective view showing the support structure. [Figure 7] This is a top view showing an exemplary retaining collar as shown in the previous figure. [Figure 8] This is a perspective view showing an exemplary retaining color as shown in the previous figure. [Figure 9] This is a perspective view showing an alternative retaining collar, which is a split-type or two-part retaining collar. [Figure 10] This is a top view showing an alternative retaining collar, which is either a split type or a two-part retaining collar. [Figure 11] This is a fractured exploded perspective view showing the support structure and the second end of the stem. [Figure 12] This is a fractured exploded perspective view showing the support structure and the second end of the stem. [Figure 13] This is a cross-sectional view showing an alternative design for the support structure. [Figure 14] This is a cross-sectional view showing another alternative design for the support structure. [Figure 15] This figure shows an example of a semiconductor processing system capable of performing semiconductor processes using the pedestal cooling system described herein. [Figure 16] This figure shows an alternative exemplary semiconductor processing system similar to the one shown in Figure 15, where a different pedestal movement mechanism is used. [Modes for carrying out the invention]

[0035] The above-mentioned diagrams are provided to facilitate understanding of the concepts described herein and are intended to illustrate, but not to limit, some implementations that fall within the scope of this disclosure. Implementations that are consistent with this disclosure and not shown in the diagrams are also considered to be within the scope of this disclosure.

[0036] As described above, semiconductor wafer processing operations are often performed on semiconductor wafers, in which case such wafers are supported on a pedestal within a processing chamber, for example, on a structure designed to support the semiconductor wafer from below. The pedestal is often supported within the processing chamber by a stem, which is generally much smaller in minimum outer cross-sectional size than the pedestal they support, for example, on the order of 3 or 4 inches in cross-sectional width (compared to the maximum cross-sectional width of the pedestal, which is typically on the order of 12 inches or more).

[0037] The stem is typically hollow to allow power cables to pass through (e.g., to supply power to RF electrodes placed within the pedestal), to form coolant supply / return passages (e.g., to supply coolant to or receive coolant from cooling passages within the pedestal), or to shield other elongated structures extending from the bottom side of the pedestal from the surrounding environment within the processing chamber and to allow them to be sent to parts outside the processing chamber.

[0038] Because the cross-sectional area of ​​the stem is relatively small compared to the cross-sectional area of ​​the pedestal supported by the stem (the cross-sectional area is generally determined in a horizontal plane intersecting such a structure, e.g., a plane perpendicular to the nominal central axis of the pedestal and stem), it is not uncommon for the stem to be subjected to a high thermal load. For example, when heat is applied to the pedestal by active heating of the pedestal using a heating element embedded in the pedestal, or by process-induced heating by radiant heating from plasma generated in the processing chamber, e.g., or by radiant heating from other components in the processing chamber, e.g., a showerhead), the stem (and the components through which it passes) is generally the only effective conductive heat transfer path available for dissipating heat from the pedestal (other than the coolant circulating through the passages in the pedestal if the pedestal is actively cooled). In implementations where the pedestal is actively cooled, naturally much of the heat from the pedestal can be carried away by a coolant that flows through the pedestal and out of the processing chamber via the stem. However, a considerable amount of heat can still be transferred through the stem. For example, in an actively cooled pedestal heated to 600°C-700°C, the stem can easily reach temperatures exceeding 300°C at its base. This can be problematic because the stem base is often interfaced with one or more elastomer seals that prevent air from being drawn into the processing chamber through the stem. Such high temperatures can degrade or damage such seals.

[0039] This specification discloses a novel design for a stem cooling system that has high cooling efficiency and, accordingly, allows the pedestal temperature to reach higher values ​​while maintaining the temperature of the stem base supporting the pedestal at a level below a specific threshold, for example, the maximum temperature to which the seal between the stem base and another component can be exposed without risk of deterioration or failure of the seal. For example, such a cooling system may enable the pedestal to be maintained at 600°C to 700°C for an extended period while maintaining the temperature of the stem base below 250°C.

[0040] A stem for a pedestal may generally have a first end connected to the pedestal and a second end connected to some support structure. Often, such a support structure may interface with a bellows seal or other flexible seal structure in some manner. The bellows seal or other flexible seal structure may interface with the processing chamber at the opposite end. Thus, the bellows seal or other flexible seal structure may provide a flexible barrier between the atmosphere inside the processing chamber and the atmosphere of the surrounding environment, for example, the atmosphere of the surrounding environment of the semiconductor manufacturing equipment in which the tool having the processing chamber is installed. The flexibility of the bellows seal or other flexible seal structure allows the support structure, as well as the pedestal and stem supported by it, to move relative to the processing chamber without disturbing the pressure environment of the processing chamber in any way.

[0041] In applications where bellows seals are used, they are typically made of stainless steel because bellows seals made of polymer materials tend to collapse, generate fine particles, release gases, and are susceptible to chemical and thermal attack. Bellows seals of other metals are typically impractical due to fatigue and / or corrosion problems with such materials. Bellows seals made of stainless steel (or other similar materials) can offer good resistance to corrosion and thermal attack, high fatigue life, and high strength. Such bellows seals are typically welded to stainless steel base / end flanges, which can serve as mounting points for attaching the bellows seal to the processing chamber and / or support structure. However, such stainless steel components typically have a much lower thermal conductivity compared to the stem. For example, a typical stem may be made of an aluminum alloy and have a thermal conductivity of about 180 W / mK, while stainless steel has the lowest thermal conductivity of any metal, e.g., about 15 W / mK. Thus, heat transfer across the boundary between the stem and such a support structure is often dramatically reduced.

[0042] In the implementations disclosed herein, various features may be used individually or in combination to still provide high-speed heat transfer from the stem to or through the support structure, and to cooling passages that are integrated with or incorporated into the support structure. Such implementations can even provide such performance when stainless steel components are in the heat transfer path. Various exemplary examples of such systems are described below with reference to the figures.

[0043] Figure 1 is a perspective view showing an exemplary apparatus including a pedestal, stem, and support structure. Figure 2 shows the same exemplary apparatus, but with its various components shown in an exploded state. As seen in Figures 1 and 2, a pedestal 100 is shown having a first surface 102 and a second surface 104 opposite the first surface 102. The first surface 102 of the pedestal 100 may be configured to support a semiconductor wafer (not shown) during semiconductor processing operations. The pedestal may be made from, for example, one of a variety of materials suitable for use in the chemical and thermal environments it is subjected to during semiconductor processing. For example, the pedestal may be made in part or whole from one or more aluminum alloys, steel alloys (such as stainless steel), ceramics (such as aluminum oxide or aluminum nitride), etc. The pedestal 100 may, in some cases, have one or more internal features that can give the pedestal additional functionality at various stages of semiconductor manufacturing. For example, the pedestal 100 may include a heating system, a cooling system, an RF electrode, etc., which may be used to add / remove heat and / or provide power that can be used to generate plasma within the processing chamber.

[0044] The stem 106 (see Figure 2; in Figure 1, the stem 106 is hidden within the bellows seal 130) may be connected to the pedestal 100 and may support the pedestal 100 within the processing chamber. The stem 106 may have, for example, a first end (invisible) connected to the second face 104 of the pedestal 100, and a second end 110 that is further away from the first face 102 and the second face 104 than the first end 108 and connects to the support structure 112. As shown, the stem 106 has an outer contour that is substantially axisymmetric with respect to the central axis of the stem 106, but other implementations may feature a non-axisymmetric stem 106, such as a radially symmetric stem 106, or a bilaterally symmetric stem 106, or even a stem 106 with no symmetry at all. However, generally speaking, as mentioned above, the stem 106 is much smaller in its minimum outer cross-sectional size (taken from the cross-sectional plane that crosses the centerline(s) of the stem 106) than in its maximum outer cross-sectional size. For example, the stem 106 may have a minimum outer cross-sectional size that is less than 50% of the maximum cross-sectional size of the pedestal 100.

[0045] The support structure 112 may be, for example, a multi-part assembly. In this example, the support structure 112 includes a seal collar 126, a support collar 182, a polymer layer 132, a load distributor 146, and a retaining collar 138. However, it will be apparent that other implementations may feature a support structure 112 having more or fewer such main components.

[0046] The support structure 112 may generally have an opening extending through the center of the support structure 112 through which, for example, cables, coolant channels, and other components can pass in and out of the stem 106. The device may also have a cooling passage 118, which may be located at least partially within the support structure 112, or may be integrated with one of the components forming the support structure 112. The cooling passage 118 may, for example, extend around most or all of the opening of the support structure.

[0047] In this example, the apparatus may include a bellows seal 130 connected at one end to a seal collar 126, for example, by welding, and connected to a mounting flange 131 (or other similar structure). In this example, the bellows seal 130, seal collar 126, and mounting flange 131 are made of metal, for example, a stainless steel alloy. The mounting flange 131 may be joined to a portion of the processing chamber, for example, to fix one end of the bellows seal 130 in place relative to the processing chamber. The bellows seal 130 may be sized such that the stem 106 can extend through the center of the bellows seal 130, i.e., the bellows seal 130 surrounds at least a portion of the stem 106.

[0048] In some implementations, the support collar 182 may have a plurality of mounting features 184 arranged around it, as shown in the figure. In this example, the support collar 182 is a circular ring having a plurality of projections extending radially outward therefrom, each projection having a mounting feature 184 extending through it. Such an implementation may also have a circular opening in the center, which may have a diameter equal to or slightly larger than the outer diameter of the seal collar 126 in the region of the seal collar 126 that aligns with the support collar 182 when the support structure 112 is assembled. Such an implementation allows the pedestal 100 to be rotated about its central axis relative to the support collar 182, thereby allowing for fine adjustment of the orientation of the pedestal 100 relative to the processing chamber in which it is installed after the support structure 112 and the pedestal 100 have been installed in a tool having a processing chamber.

[0049] However, in other implementations, the mounting feature 184 may be connected to other components of the support structure 112. For example, in some implementations, the mounting feature 184 may be integrated with the seal collar 126. In such implementations, a separate support collar 182 may not be necessary.

[0050] The apparatus may also include a retaining collar 138 which can be firmly connected to the stem 106 by, for example, a plurality of screw fasteners 174a. The retaining collar 138 may have, for example, a first portion that extends through the polymer layer 132 and the opening of the load distributor 146 and abuts against the second end 110 of the stem 106.

[0051] The polymer layer 132 may actually be used as a spring in an implementation where the cooling passage 118 is a separate but integrated component from the support structure 112, to compress the cooling passage 118 in contact with other features of the support structure 112, and to ensure good thermally conductive contact between the cooling passage 118 and one or more elements of the support structure 112. The polymer layer 132 may also be used to provide an adaptive gap filler that can help to give the stem 106 a desired clamping force, as will be described later with reference to other figures.

[0052] The load distributor 146 may be configured, if used, to apply a compressive load to, for example, the polymer layer 132. The load distributor 146 may have an overall shape similar to that of the polymer layer 132, for example. In some implementations (such as those shown), the load distributor 146 may be connected to the seal collar 126 by a number of screw fasteners 174c. The polymer layer 132 may be interposed between the load distributor 146 and the seal collar 126, if present. In at least some such implementations, the rest of the support structure 112 may be removed from the support structure 112, leaving at least the polymer layer 132, the seal collar 126 and the load distributor 146 in place. The term “interposed” as used in the context of “part A is interposed between part B and part C” will be understood to refer to an arrangement where part A is placed between part B and part C, but not necessarily directly between part B and part C. For example, the fact that part D may be between part B and part C, and between part A and part B, does not mean that part A is no longer intervening between part B and part C.

[0053] The retaining collar 138 may be configured to be firmly connected to the stem 106, as shown in the figure, and may function in cooperation with other components of the support structure 112 to hold the stem 106 in place relative to the support structure 112. In the illustrated example, the retaining collar 138 has two main parts: a central cylindrical first part that extends upward through the load distributor 146, the polymer layer 132, and the central opening of the seal collar 126, and then abuts against the second end 110 of the stem 106; and a second part that extends radially outward from the first part. The second part may function, for example, as a flange that can apply compressive force to the polymer layer 132, the load distributor 146, and a segment of the cooling passage 118 interposed between the stem 106 and the second part of the retaining collar 138.

[0054] Figure 3 is a cross-sectional view showing the apparatus of Figure 1. As seen in Figure 3, the first surface 102 of the pedestal 100 may be used to support the wafer 101 (shown by the dotted outline) during semiconductor processing operations. In this example, the pedestal 100 has both active heating and cooling features. For example, the pedestal 100 may include one or more resistance heating elements 1112 that can generate heat to heat the first surface 102 of the pedestal 100. The pedestal 100 may also include one or more pedestal cooling passages 1114 through which a coolant can be flowed to lower the temperature of the pedestal 100. It will be understood that the pedestal cooling passages 1114 may follow one or more paths that traverse the entire cross-sectional area of ​​the pedestal 100 in a generally distributed manner (the diagram in Figure 3 is obtained in a cross-section that bisects the right-hand region where there are no portions of the pedestal cooling passages). The stem 106 is hollow so that, for example, a first electrical conductor (or cable) 180a and a second electrical conductor (or cable) 180b for supplying power to the resistive heating element 1112, a pedestal coolant supply passage 180c and a pedestal coolant return passage 180d (not shown), and a sensor cable 180e can extend from the second face 104 of the pedestal 100 through the second end 110 of the stem 106 (and through the support structure 112). As can be seen from the figure, the elongated structure 180 may extend roughly along the central axis 154 of the pedestal 100 and / or the stem 106.

[0055] As can be seen in the figure, the stem 106 has a first end 108 connected to the second face 104 of the pedestal 100. In this example, the stem 106 has a circular pattern of through holes that align with the threaded holes in the second face 104 of the pedestal 100. Multiple screw fasteners 174e are inserted through the through holes in the first end 108 of the stem 106 into the threaded holes in the second face 104 of the pedestal 100, thereby allowing the first end 108 of the stem 106 to be clamped to the pedestal 100. In some other configurations, the stem 106 may be welded to the second face 104 of the pedestal 100, and in yet another configuration, the stem 106 may be connected to the pedestal 100 by machining the stem 106 and the pedestal 100 (or a secondary part thereof) from the same piece of material, for example, the stem 106 being continuous with the bottom of the pedestal 100.

[0056] As previously mentioned, the bellows seal 130 may be connected at one end to the mounting flange 131 or other similar structure, or at the other end to the support structure 112.

[0057] Figure 4 shows details of the area circled in Figure 3 and presents details of the support structure 112. As seen in Figure 4, the support structure 112 includes one or more first surfaces 114 that axially bond to one or more second surfaces 116 of the stem, for example, at or near the second end 110 of the stem 106, along the central axis 154.

[0058] In this example, there are two first surfaces 114, one of which is positioned on the seal collar 126 and the other on the end of the first portion 140 of the retaining collar 138. When the support structure 112 is fully assembled and joined to the second end 110 of the stem 106, both first surfaces 114 are in contact with the second surface 116 of the stem 106. However, in other configurations, there may be more or fewer first surfaces 114 and / or second surfaces 116.

[0059] In some implementations, there may be a compressed seal 124 between one or more first surfaces 114 and one or more second surfaces 116 to prevent gas that could be trapped between the bellows seal 130 and the stem 106 from leaking through the support structure 112 (or to prevent atmospheric gas from leaking into the space between the bellows seal 130 and the stem 106 (and thus into the processing chamber)). The seal 124 may be housed in a seal groove 122 which may be formed in one or both of the one or more first surfaces and one or more second surfaces. In this example, the seal groove 122 is located on a first surface 114 which is part of the seal collar 126, but it will be readily apparent that such a seal groove 122 may instead be located on one of the one or more second surfaces 116.

[0060] Furthermore, Figure 4 shows a first cooling passage segment 118a in which at least one first surface 114 is interposed between the first cooling passage segment 118a and the stem 106. Such an arrangement helps to provide a direct heat conduction path between the stem 106 and the first cooling passage segment 118a without, for example, reversing in the direction of heat flow. This can increase the rate at which the first cooling passage segment 118a can remove heat from the stem 106.

[0061] In Figure 4, the first cooling passage segment 118a is positioned between the second portion 142 of the retaining collar 138 and the stem 106, for example, the second(s) surfaces 116 of the stem 106. In the illustrated example, the first portion 140 of the retaining collar 138 is compressed in contact with the second end 110 of the stem 106, for example, one of the one or more second surfaces 116. Such compression can be performed, for example, by a screw fastener 174a that can be inserted into a through hole in the first portion 140 of the retaining collar 138 and a threaded hole in the second end of the stem 106. Thus, the first portion 140 of the retaining collar 138 can function as a heat conduction path from the stem 106, through the seal collar 126 and polymer layer 132, to the first cooling passage segment 118a. As described above, the seal collar 126 may in some cases be made of a stainless steel alloy and therefore may have a relatively low thermal conductivity. Similarly, the polymer layer 132 has an even lower thermal conductivity than the seal collar 126. Therefore, the first portion 140 of the retaining collar 138 can provide an alternative heat conduction path from the stem 106 to the first cooling passage segment 118a.

[0062] To facilitate heat conduction through the first portion 140 of the retaining collar 138, the retaining collar 138 may be made of a material with high thermal conductivity, such as copper or a copper alloy, or aluminum or an aluminum alloy. The first cooling passage segment 118a may similarly be made of such a material. The retaining collar 138 may also include a first concave region 144 having a contour that matches the first cooling passage segment 118a, for example. In this example, the first cooling passage segment 118a is a circular cross-section tube bent in a C-shape or arc shape, having an inner radius that matches or is slightly larger than the radius of the first portion 140 of the retaining collar 138 (so that the first cooling passage segment 118a extends around the first portion 140 of the retaining collar 138). The first concave region 144 in this example is a channel having a substantially semicircular cross-sectional contour. The semicircular cross-sectional contour has nominally the same radius as the outer radius of the circular cross-section tube forming the first cooling passage segment 118a. The channel providing the first concave region 144 follows a path that coincides with the path of the first cooling passage segment 118a. This allows the first cooling passage segment 118a to be positioned in contact with the first concave region 144.

[0063] In some implementations, the load distributor 146 may have a similar concave region, for example, a second concave region 150, on the face of the load distributor 146 facing the first cooling passage segment 118a when used. The second concave region 150 may have a cross-sectional shape similar to that of the first concave region 144, for example, and may follow a similar path, thereby allowing the first cooling passage segment 118a to also be located within and in contact with the first concave region 144. However, if the first cooling passage segment 118a is provided using a tube having, for example, an asymmetrical profile, for example, a semicircular profile transitioning to a rectangular profile, it will be understood that the first concave region 144 and the second concave region 150 may have different cross-sectional profiles but can still follow similar paths.

[0064] The polymer layer 132 can function as a compliance element, allowing the first portion 140 of the retaining collar 138 to be pressed to good thermal contact with the stem, while simultaneously applying a smaller compressive load to the portion of the seal collar 126 that is compressed between the load distributor 146, the polymer layer 132, the support collar 182, and the second portion 142 of the retaining collar 138 and the stem 106, for example, between the second surface(s) 116 of the stem 106. This causes the first cooling passage segment 118a to be pressed against the first concave region 144 and the second concave region 150, increasing the thermal contact area between the first cooling passage segment 118a and the retaining collar 138 and load distributor 146. It should be noted that the retaining collar 138 and load distributor 146 may be configured such that a gap 164 exists between the closest surfaces of the retaining collar 138 and load distributor 146 when at least the first cooling passage segment 118a is in contact with both the retaining collar 138 and load distributor 146 but is in an uncompressed state. The gap 164 may be relatively small. This works to ensure that the compressive load from the polymer layer 132, which is led to the retaining collar 138 through the load distributor 146 and then through the first cooling passage segment 118a, passes through the first cooling passage segment 118a completely or almost completely, thereby avoiding a scenario in which the load is split between the first cooling passage segment 118a and the retaining collar 138, or a scenario in which all or almost all of the load enters the retaining collar 138 from the load distributor 146 and little or no passes through the first cooling passage segment 118a. In such examples, the amount of force required to press the first cooling passage segment 118a into contact with the first concave region 144 and / or the second concave region 150 may be smaller, and as a result, the thermal contact boundary between the first cooling passage segment 118a and the first concave region 144 and / or the second concave region 150 has a much lower thermal conductivity than would be obtained if a gap 164 were provided.

[0065] Therefore, the polymer layer 132 may be sized such that both the first surface 134 of the polymer layer 132 facing the stem and the second surface 136 of the polymer layer 132 facing the opposite direction are in contact with the other parts of the support structure 112 (the parts that the polymer layer 132 is in contact with when the support structure 112 is fully assembled), but the first part 140 of the retaining collar 138 is not in contact with the second end 110 of the stem 106 when the polymer layer 132 is unloaded or uncompressed.

[0066] Figure 5 shows the same cross-sectional detail as Figure 4, but the stem 106 is partially pulled out from the support structure 112, and the retaining collar 138 and polymer layer 132 are partially pulled out from the seal collar 126 by different amounts, respectively. Figure 5 is provided solely to give greater clarity with respect to the first surfaces 114a and 114b (referred to simply as the first surface 114 above) and the second surface 116, as well as the first surface 134 and the second surface 136 of the polymer layer 132.

[0067] Figure 6 is an exploded perspective view showing the support structure 112 described above. Parts of the bellows seal 130 and stem 106 can also be seen. The bellows seal 130 is shown as being removed from the seal collar 126, but is usually attached to the seal collar by welding or in other ways.

[0068] In this example, the seal collar 126 may be inserted through an opening in the support collar 182 such that the support collar 182 is restricted from radial movement relative to the seal collar 126. The seal collar 126 may have a flange extending radially outward from the portion of the seal collar 126 that extends through the support collar 182. The flange may support the seal collar 126 axially relative to the support collar 182. The support collar 182 may have a plurality of mounting features 184 arranged around the outer circumference of the support collar 182, as described above. The mounting features 184 may be through holes or threaded holes in some implementations, and may be used to receive or mount support features such as rods, columnar bodies or other structures, or other structural supports that can support the support collar 182 to a movable base that can be used to move the pedestal 100 vertically up and down. In this configuration, the support collar 182 is bolted to the seal collar 126 using multiple screw fasteners 174d, thereby joining the support collar 182 and the seal collar 126 to the assembly.

[0069] In this example, the polymer layer 132 and the load distributor 146 may be attached to the support collar 182 by, for example, a screw fastener 174c. Such a screw fastener 174c may be, for example, a shoulder screw, which can hold the load distributor 146 in place relative to the seal collar 126 and the support collar 182, but in contact with the bottom surface of the support collar 182, thereby exerting only a limited amount of compressive force on the polymer layer 132.

[0070] The second end 110 of the stem 106 may be inserted into the seal collar 126 during assembly after the seal 124 is set in the seal groove 122. The cooling passage 118, for example, the first cooling passage segment 118a, may be positioned in contact with the second concave region 150 (which may extend around the opening 148). The first portion 140 of the retaining collar 138 is then inserted through the first cooling passage segment 118a and the opening 148 of the load distributor 146 (as well as similar openings in the polymer layer 132 and the seal collar 126) so as to abut against the second end 110 of the stem 106, thereby allowing the first cooling passage segment 118a to be positioned in the first concave region 144. The retaining collar 138 may be connected to the load distributor 146 by a plurality of screw fasteners 174b, for example, inserted through holes in the retaining collar 138 into the screw holes of the load distributor 146. Such fasteners 174b can function to hold the retaining collar 138 in place relative to the load distributor 146 and can apply some compression to the first cooling passage segment 118a. However, the retaining collar 138 may also be held in place by a screw fastener 174a, which may be inserted through a through-hole in the first portion 140 of the retaining collar 138 into a screw hole in the second end 110 of the stem 106.

[0071] It should be noted that the first cooling passage segment 118a may be fluidically connected to, for example, the second cooling passage segment 118b and the third cooling passage segment 118c, and fluidly interposed between them. For example, the cooling passage may be a tube of a certain length bent into a specific shape including the shape of the first cooling passage segment 118a, for example, a copper tube. The second cooling passage segment 118b and the third cooling passage segment 118c may extend in a direction perpendicular to the plane on which the path followed by the first cooling passage segment 118a is located. Parts of the cooling passage, for example, the ends of the second cooling passage segment 118b and the third cooling passage segment 118c that are not connected to the first cooling passage segment 118a, may be spatially clamped to the support structure 11 or otherwise fixed in some implementations.

[0072] It should be noted that the retaining collar 138 can be removed from the support structure 112 by removing, for example, the screw fasteners 174a and 174b, while leaving the first cooling passage segment 118a, as well as the second and third cooling passage segments 118b and 118c, in place, without having to move the second and third cooling passage segments 118b and 118c relative to the first part. Such a design allows the stem 106 (and the pedestal 100 it supports) to be removed from the support structure 112 without having to disable the cooling passage 118, for example, without having to deseal or remove the cooling passage 118. This avoids, for example, the need to drain the coolant from the cooling system before removing the stem 106, thereby reducing the time and effort required to remove and reinstall the pedestal 100 (or replace it with a new pedestal 100).

[0073] Figures 7 and 8 are a top view and a perspective view showing an exemplary retaining collar 138 as shown in the previous figures. The first concave region 144 can be seen in Figures 7 and 8. As can be seen from the figures, the first portion 140 of the retaining collar 138 may have an essentially cylindrical outer surface, similar to the outer surface of the stem 106. However, the inner edge 160 of the first portion 140 of the retaining collar 138 may optionally have a plurality of lobes 170 extending radially inward from the outer edge 158. Such lobes 170 may, for example, receive through holes 176 into which a screw fastener 174a can be inserted. In some cases, the stem 106 may also have fitting lobes, for example, lobes (not indicated in the figures but visible) that are similar in size and shape and rotatably aligned with the lobes 170 of the retaining collar 138. The lobes of the retaining collar 138 may also receive threaded holes (not shown) into which a screw fastener 174a can be screwed. For clarity, it will be understood that the lobes 170 of the retaining collar 138 and the lobes of the stem (if the stem has lobes) may in some cases (or vice versa, depending on the context) be referred to as the "first lobe" and the "second lobe," respectively. In some cases, the lobes of the retaining collar 138 may terminate on a first surface (which may be multiple) 114, or have a first surface 114, for example, terminating coplanar with the first surface 114, and the lobes of the stem 106 may terminate on a second surface (which may be multiple) 116, or have a second surface 116, for example, terminating coplanar with the second surface 116.

[0074] Figures 9 and 10 show perspective and top views of an alternative retaining collar, which is a split or two-part retaining collar. As shown, the retaining collar features two halves 138a and 138b. However, other features shown in Figures 9 and 10 are the same as those of the retaining collar 138 in Figures 7 and 8 and will not be repeated here. By splitting the retaining collar 138 into two halves 138a and 138b, the retaining collar 138 can be removed from (or attached to) the support structure 112 without the need to remove the cooling supply channel, cooling return channel, or first or second electrical conductor (if any). Note that the first concave region 144 provided in each of the halves 138a and 138b is symmetrical and has, for example, a mirror image of the portion with respect to a central plane perpendicular to the dividing plane that separates the two halves 138a and 138b from each other. Such a structure makes the two halves 138a and 138b interchangeable, thereby reducing the number of potentially different unique parts and making incorrect assembly more difficult. However, in other implementations, the two halves 138a and 138b do not have to be symmetrical, and for example, each may have its own unique component design.

[0075] The use of the first lobes 170 within the first portion 140 of the retaining collar 138 allows the retaining collar 138 to increase in thickness in the region having the first lobes 170 (thus resulting in larger thermally conductive heat transfer paths), while also providing space between the first lobes 170 to allow various elongated structures 180, e.g., 180a-180d, to pass through the retaining collar 138. For example, each of the elongated structures 180a-180d may have a portion positioned between two adjacent first lobes 170.

[0076] Figures 11 and 12 are broken exploded perspective views showing the support structure 112 (only the seal collar 126 and retaining collar 138 are shown) and the second end 110 of the stem 106. Figures 11 and 12 are provided primarily to help show the contact area 152 where the first(or more) surfaces 114 of the support structure 112 and the second(or more) surfaces 116 of the stem 106 overlap each other when viewed along the central axis 154. The contact area 152 is indicated by diagonal hatching in Figures 11 and 12 and defines a cross section of the reference volume section 156 extending along the central axis 154. In some implementations, the first cooling passage segment 118a may be located at least partially (or mostly) within the reference volume section 156. Such an arrangement, for example, can position the first cooling passage segment 118a below the contact area 152, thereby reducing the distance that heat must travel from the contact area 152 to the first cooling passage segment 118a.

[0077] It will be understood that the above principles and concepts can be implemented in various forms. In particular, the various elements shown as separate parts or components in the above examples may be combined in other implementations, or such parts or components may be arranged differently.

[0078] Figure 13 shows a cross-section similar to that of Figure 4. Elements in Figure 13, indicated by reference numerals having the same last two digits as those in Figure 4, can be assumed to have substantially the same function and structure unless explicitly or implicitly indicated otherwise. The implementation in Figure 13 is substantially the same as that in Figure 4, except that the illustrated implementation does not have a load distributor 1346 and the first cooling passage segment 1318a is not provided by a separate piece of tubing clamped between the retaining collar 1338 and the load distributor 1346. Instead, the retaining collar 1338 includes within it the first cooling passage segment 1318a, for example, a channel or passage provided within the body of the retaining collar 1338 following a C-shaped path. The channel or passage may be connected at one end to a coolant inlet and at the other end to a coolant outlet. If the first cooling passage segment 1318a is provided by a channel within the retaining collar 1338, in some implementations the channel may be covered by a plate welded, bonded, or otherwise sealed to the rest of the retaining collar 1338. If the retaining collar 1338 is manufactured using additive manufacturing, such as laser metal sintering, the first cooling passage segment may simply be printed in place during the manufacturing process.

[0079] Figure 14 shows another alternative configuration in which the first cooling passage segment 1418a is formed within the retaining collar 1438 but positioned above (or overlapping with) the polymer layer 1432. The elements in Figure 14, indicated by reference numerals having the same last two digits as the elements in Figure 4, can be assumed to have substantially similar function and structure unless explicitly or implicitly indicated otherwise. Such a technique allows the first cooling passage segment 1418a to be positioned very close to the first(or more) and second(or more) surfaces, thereby dramatically shortening the conduction heat transfer path from the stem 1406 to the first cooling passage segment 1418a.

[0080] The examples in Figures 13 and 14 can provide similarly improved cooling performance compared to the earlier examples described herein, but maintenance and installation may be more difficult because the first cooling passage segment 118a is located within the retaining collar 138. Therefore, removing the retaining collar 138 to remove the stem 106, for example, may require removing the coolant from the first cooling passage segment 118a.

[0081] The pedestal 100, stem 106, and support structure 112 described herein are used, for example, in semiconductor processing operations where the wafer being processed is exposed to relatively high temperatures, e.g., 600°C, while the boundary where the stem 106 joins the support structure 112 (where the seal 124 is located) is maintained at a much lower temperature, e.g., below 250°C. For example, in the configuration shown in Figure 1, when the pedestal 100 is maintained at a temperature of 600°C, the temperature of the second end 110 of the stem 106 can be maintained at approximately 235°C when the retaining collar 138 is made of an aluminum alloy, and potentially at approximately 215°C when the retaining collar 138 is made of a copper alloy or pure copper. Using a high thermal conductivity material such as copper or an alloy thereof for the retaining collar 138 and the first cooling passage segment 118a provides a heat transfer path with much higher thermal conductivity than what can be achieved with stainless steel or other materials commonly used in semiconductor processing equipment.

[0082] For example, the use of copper is often avoided due to its reaction with many types of semiconductor processing gases, and exposure of copper surfaces to such gases can lead to the generation of undesirable fine particles. Such fine particles can, for example, deposit on the wafer being processed, rendering the wafer unusable.

[0083] For example, in the design of Figure 3, both the retaining collar 138 and the first cooling passage segment 118a are located outside the seal boundary surrounding the inside of the semiconductor processing chamber where the pedestal 100 resides, thereby protecting the retaining collar 138 and the first cooling passage segment 118a from potential exposure to semiconductor processing gases and preventing any particulate matter that may be released from the retaining collar 138 and the first cooling passage segment 118a from reaching the inside of the semiconductor processing chamber. This makes it possible to use copper or a copper alloy for the retaining collar 138 and the first cooling passage segment 118a without the risk of the copper being exposed to process gases inside the semiconductor processing chamber.

[0084] Generally speaking, the stem 106 may be made of aluminum, which may be chemically compatible with the process gases to which the stem 106 and pedestal 100 may be exposed, and may also have a relatively high thermal conductivity (significantly lower than copper, for example, about half that of copper). However, the metal bellows seal 130 is typically made of stainless steel because it needs to be chemically resistant and highly resistant to fatigue failure. As mentioned earlier, the metal bellows seal 130 is typically welded to a seal collar 126, which may also be made of stainless steel. The seal collar 126 may function as a seat against which the stem 106 abuts to seal in contact with the seal 124.

[0085] By using copper for the retaining collar 138, a high thermal conductivity path is provided from the stem 106 to the first cooling passage segment 118a, which exists in parallel with a much lower thermal conductivity path provided from the stem to the first cooling passage segment 118a via the seal collar 126 (presumably made of stainless steel) and the polymer layer 132 (made of polymer material). Such a configuration allows most of the heat from the stem 106 to flow through the retaining collar 138 to the first cooling passage segment 118a, thereby significantly reducing the amount of heat flowing through the seal collar 126 and the polymer layer 132. This reduces the possibility of heat buildup in the seal collar 126 and the polymer layer 132, which could damage the polymer layer 132 and / or seal 124.

[0086] Furthermore, as mentioned above, arranging the first cooling passage segment 118a at least partially within the reference volume section 156 can further enhance the cooling efficiency of such a pedestal assembly by bringing the first cooling passage segment 118a closer to the end of the retaining collar 138 that joins the stem 106, thereby reducing the length of the heat conduction path from the stem 106 to the first cooling passage segment 118a.

[0087] Figure 15 shows an example of a semiconductor processing system capable of performing such a process. As can be seen from the figure, the pedestal 100 and the first end of the stem 106 are located within the internal volume 190 of the processing chamber 186. However, the second end of the stem 106 is located outside the internal volume 190 of the processing chamber 186. A showerhead 188 is located within the internal volume 190 and may be used to distribute one or more processing gases to the wafer 101, which can be supported by the pedestal 100 during wafer processing operations.

[0088] The second end of the stem 106 may be connected to a support structure 112 which is fixedly coupled to the movable base 196 of the hexapod mechanism 192. The hexapod mechanism 192 may also include a fixed base 194 and a plurality of linear actuators 198, for example six, each having a first end 1100 connected to the fixed base 194 and a second end 1102 connected to the movable base 196. The linear actuators 198 may be configured to form a static kinematic system, which, by controlled operation of the linear actuators 198, can move the movable base 196 vertically, horizontally, and rotationally about both the horizontal and vertical axes.

[0089] Figure 16 shows an alternative exemplary semiconductor processing system similar to that shown in Figure 15, except that the hexapod mechanism 192 is replaced by a single-axis vertical lift mechanism 1104. The vertical lift mechanism 1104 may have, for example, a base portion 1106 which can be substantially fixed to the processing chamber 186 and a movable portion 1108 which can be movably connected to the base portion 1106. For example, the base portion 1106 may include an actuator 1110 which can be used to drive a linear screw that passes through a nut or other screw-type interface in the movable portion 1108. By acting the actuator 1110, the linear screw can be rotated, thereby moving the movable portion 1108 of the vertical lift mechanism vertically up and down.

[0090] The stem design described above is configured to provide a conductive heat transfer path with high thermal conductance, thereby enabling the pedestal to be maintained at a significantly higher temperature, e.g., 600°C-700°C, while the base of the stem supporting the pedestal can be maintained at a much lower temperature, e.g., 250°C. However, it will be understood that such a design may be implemented slightly differently in some cases to intentionally provide lower thermal conductance. Since the retaining collar acts as the primary conductive heat transfer path from the stem to the cooling passage segment, it is relatively easy to readjust such a pedestal to have lower thermal conductivity, for example, by using a retaining collar made of a material with lower thermal conductivity. Such a configuration may be advantageous in semiconductor processing tools where a slower heat transfer rate from the pedestal is desirable. For example, in some semiconductor processes, heat can be generated within the pedestal by the process state itself, for example, due to RF energy absorbed by the pedestal and / or due to chemical reactions or plasma occurring within the semiconductor processing chamber, without requiring a separate heater system. In some such cases, it may still be desirable to maintain the pedestal at a high temperature (though likely lower than the 600°C–700°C examples mentioned above). The heat generated in such a process may be sufficient to heat the pedestal to the desired target temperature. However, if the stem has high thermal conductance, the heat transfer coefficient from the pedestal can become high enough to make it difficult to maintain the desired target temperature.In such cases, the retaining collar can effectively be used as a thermal choke point, and the thermal conductance of the retaining collar can be intentionally adjusted to be lower than when it is made of a material such as solid copper or aluminum, for example, by fabricating the retaining collar from a material with lower thermal conductivity, such as stainless steel, brass, nickel or bronze alloy, or glass-filled or metal-filled composite, or plastic, polyamide, and / or by providing a portion of the first part of the retaining collar with one or more layers of such material. Furthermore, the radial thickness of the first part of the retaining collar and / or the length of the first part of the retaining collar may be made thinner and / or longer, respectively, to reduce heat transfer through the retaining collar and result in a further reduction in thermal conductance through the retaining collar. Thus, it will be recognized that although the structures described herein are designed to provide a conductive heat transfer path with high conductivity, they can also be reconfigured to provide a conductive heat transfer path with much lower thermal conductance, depending on the thermal requirements of a particular semiconductor process. Such methods can offer a completely passive option for reducing heat flow from the pedestal, compared, for example, to changing the flow rate and / or temperature of the coolant.

[0091] Semiconductor processing tools incorporating the pedestals, stems, and support structures described herein may be controlled by a controller, which may be programmed to control any of the processes disclosed herein, such as the process for controlling the pedestal, as well as any other processes or parameters not described herein, such as the delivery of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer entry and exit from the chamber, and other transfer tools and / or load locks connected to or interfaced with a particular system.

[0092] Generally speaking, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive and issue instructions, control operations, enable cleaning operations, enable endpoint measurement, etc. Integrated circuits may include chips in the form of firmware that store program instructions, chips defined as digital signal processors (DSPs), application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). Program instructions may also be instructions communicated to the controller in the form of various individual settings (or program files) that define operating parameters for performing a particular process on a semiconductor wafer or system. In some examples, operating parameters may be part of a recipe defined by a process engineer to achieve one or more processing steps during the manufacturing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0093] In some implementations, the controller may be part of, or coupled to, a computer integrated with, coupled to, networked to, or in some way networked to, the system, or a combination thereof. For example, the controller may be all or part of a “cloud” or fab-host computer system, and may also enable remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, examine the history of past manufacturing operations, examine trends or performance metrics from multiple manufacturing operations, modify parameters of the current process, set processing steps to follow the current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the system over a network that may include a local network or the internet. The remote computer may include a user interface that allows input or programming of parameters and / or settings, which are then communicated from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify the parameters of each of the processing steps performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool to which the controller is configured to interface or control. Therefore, as described above, the controllers may be distributed, for example, by comprising one or more individual controllers that are networked together and operate toward a common purpose, such as the processes and control described herein. An example of a distributed controller for such purposes may be one or more integrated circuits on a chamber that communicate with one or more remotely located integrated circuits (such as platform-level or part of a remote computer) that are combined to control the processes on the chamber.

[0094] Exemplary pedestals provided herein may be mounted in or on a semiconductor processing tool, together with plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, clean chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing systems that may be associated with or used in the fabrication and / or manufacture of semiconductor wafers.

[0095] As described above, depending on one or more process steps performed by the tool, the controller may communicate with one or more of the following: other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used for material transport to carry wafer containers to and from tool locations and / or load ports in the semiconductor manufacturing plant.

[0096] Where ordinal designations such as (a), (b), (c)... or (1), (2), (3)... are used in this disclosure and claims, it should be understood that they do not convey a specific order or sequence, unless such an order or sequence is explicitly indicated. For example, if there are three steps labeled (i), (ii), and (iii), it should be understood that, unless otherwise indicated, these steps may be performed in any order (even simultaneously, unless otherwise contraindicated). For example, if step (ii) involves handling an element created in step (i), then step (ii) may be considered to occur at some point after step (i). Similarly, if step (i) involves handling an element created in step (ii), then the reverse should be understood. It should also be understood that the use of ordinal designations such as "first," e.g., "first item," in this specification should not be read as implying or essentially suggesting that there is necessarily a "second," e.g., "second item."

[0097] Where used herein, expressions such as “for each <item> of one or more <items>” or “for each <item> of one or more <items>” should be understood to include both single and multiple sets of items; that is, the expression “for each...” should be understood to be used in the sense that it is used in programming languages ​​to refer to each item within a set of items being referenced. For example, if the set of items being referenced is a single item, “each” refers only to that single item (despite the fact that the dictionary definition of “each” is often defined as a term referring to “one of two or more things”) and does not mean that at least two of those items must exist. Similarly, the terms “set” or “subset” should not be considered by themselves to necessarily include multiple items, and it should be understood that a set or subset can include only one member or more members (unless the context indicates otherwise).

[0098] As used herein and in conjunction with a range of values, the term “between” should be understood to include the start and end values ​​of that range unless otherwise specified. For example, between 1 and 5 (between 1 and 5) should be understood to include the digits 1, 2, 3, 4 and 5, as well as the digits 2, 3 and 4.

[0099] The term “operably connected” should be understood to refer to a state in which two components and / or systems are directly or indirectly connected such that, for example, at least one component or system can control the other. For example, a controller may be described as operably connected to a resistive heating unit, which includes a controller connected to a subcontroller of the resistive heating unit, the subcontroller being electrically connected to a relay, the relay being configured to controllly connect or disconnect the resistive heating unit to a power source capable of providing an amount of energy that can power the resistive heating unit to produce the desired degree of heating. The controller itself is likely unable to directly supply such power to the resistive heating unit due to the currents involved, but it will be understood that the controller is nevertheless operably connected to the resistive heating unit.

[0100] The examples and implementations described herein are for illustrative purposes only, and it should be understood that various modifications or changes will be suggested to those skilled in the art. Various design alternatives may be implemented, although various details have been omitted for clarity. Therefore, these examples should be considered illustrative and not limiting, and this disclosure should not be limited to the details given herein, but may be modified within the scope of this disclosure.

[0101] While the above disclosures focus on one or more specific exemplary implementations, it should be understood that they are not limited to the examples described and can be applied to similar variations and mechanisms, and such similar variations and mechanisms are also considered to be within the scope of this disclosure. [Explanation of symbols]

[0102] 100 Base, 101 Wafer, 102 First surface, 104 Second surface, 106 Stem, 108 First end, 110 Second end, 112 Support structure, 114 First surface, 114a First surface, 114b First surface, 116 Second surface, 118 Cooling passage, 118a First cooling passage segment, 118b Second cooling passage segment, 118c Third cooling passage segment, 122 Seal groove, 124 Seal, 126 Seal collar, 130 Bellows seal, 131 Mounting flange, 132 Polymer layer, 134 First surface, 136 Second surface, 138 Retaining collar, 140 First part, 142 Second part, 144 First concave region, 146 Load distributor, 148 Opening, 150 Second concave region, 152 Contact area, 154 Central axis, 156 Reference volume section, 158 Outer edge, 160 Inner edge, 164 Gap, 170 Lobe, 174a Screw fastener, 174c Screw fastener, 174e Screw fastener, 176 Through hole, 180 Elongated structure, 180a First conductor, 180b Second conductor, 180c Pedestal coolant supply passage, 180d Pedestal coolant return passage, 180e Sensor cable, 182 Support collar, 184 Mounting feature, 186 Processing chamber, 188 Shower head, 190 Internal volume section, 192 Hexapod mechanism, 194 Fixed base, 196 Movable base, 198 Linear actuator, 1100 First end, 1102 Second end, 1104 Single-axis vertical lift mechanism, 1106 Base section, 1108 Movable section, 1110 Actuator, 1112 Resistive heating element, 1114 Pedestal cooling passage, 1318a First cooling passage segment, 1338 Retaining collar, 1346 Load distributor, 1418a First cooling passage segment, 1432 Polymer layer, 1438 Retaining collar

Claims

1. It is a system, A pedestal having a first surface configured to support a semiconductor wafer during semiconductor processing operations, and a second surface opposite to the first surface, A stem having a first end connected to the pedestal and a second end positioned further from the second face than the first end of the stem, A support structure connected to the second end of the stem, having at least one first surface that is axially joined to a second surface located at or near the second end of the stem, A first cooling passage segment, wherein the first cooling passage segment is arranged such that at least one first surface is interposed between the first cooling passage segment and the stem, A system equipped with these features.

2. The system according to claim 1, The support structure includes a seal collar connected to a bellows seal, The bellows seal surrounds at least a portion of the stem, The aforementioned bellows seal is made of metal, in this system.

3. The system according to claim 2, The aforementioned support structure is A polymer layer interposed between at least a portion of the seal collar and the first cooling passage segment, A retaining collar having a first portion that abuts the second end of the stem and a second portion connected to the first portion, wherein the first cooling passage segment is disposed between the second portion of the retaining collar and the second surface of the stem, A system that further enhances this feature.

4. The system according to claim 3, The first cooling passage segment is a tube extending around the first portion of the retaining collar, The support structure is configured such that the first portion of the retaining collar is in contact with and compressed against the second end of the stem. A system in which at least a portion of the polymer layer adjacent to the seal collar is in a compressed state.

5. The system according to claim 4, The aforementioned polymer layer is It has a first surface facing the stem and a second surface facing in the opposite direction to the first surface, A system in which the size of the retaining collar is determined such that the first portion of the retaining collar does not come into contact with the second end of the stem when the polymer layer is in an uncompressed state and both the first surface of the polymer layer and the second surface of the polymer layer are in contact with the other part of the support structure.

6. The system according to claim 4, The at least one first surface of the support structure and the second surface of the stem define a contact region where the at least one first surface and the second surface overlap when viewed along the central axis of the stem extending between the first end and the second end of the stem. The system wherein the first cooling passage segment is a reference volume defined by the inner and outer edges of the contact area, and is at least partially located within the reference volume extending along the central axis of the stem.

7. The system according to claim 4, The tube follows a path around the first portion of the retaining collar, The second portion of the retaining collar has a first concave region extending around the first portion of the retaining collar. The system wherein the tube is positioned within the first concave region and in contact with the first concave region.

8. The system according to claim 7, The support structure further comprises a load distributor, and the load distributor is Between the first cooling passage segment and the polymer layer, Between the second portion of the retaining collar and the polymer layer, the cooling passage segment is interposed between at least a portion of the second portion of the retaining collar and a portion of the load distributor, between the second portion of the retaining collar and the polymer layer, A system that is at least partially involved in something.

9. The system according to claim 8, The load distributor has an opening through which the first portion of the retaining collar extends, The load distributor has a second concave region extending around the opening, The system wherein the tube is positioned within the second concave region and in contact with the second concave region.

10. The system according to claim 8, wherein the first cooling passage segment is in contact with at least the load distributor and the retaining collar, but when the first cooling passage segment is not compressed between the load distributor and the retaining collar, a gap exists between the load distributor and the second portion of the retaining collar.

11. A system according to any one of claims 3 to 10, wherein the second end of the stem has a first inner circumference, the first inner circumference having a plurality of first lobes extending radially inward from the outermost portion of the first inner circumference.

12. The system according to claim 11, The retaining collar has a second inner circumference, and the second inner circumference has a plurality of second lobes extending radially inward from the outermost portion of the second inner circumference. A system in which the first lobe and the second lobe are aligned with each other in the direction of rotation.

13. The system according to claim 12, wherein the first lobe terminates on the second surface, and the second lobe terminates on the same plane as the at least one first surface.

14. The system according to claim 11, further comprising a plurality of elongated structures extending from the second face of the pedestal through the stem, each of which elongated structures has a portion positioned between two of the first lobes adjacent to each other.

15. A system according to claims 7 to 10, further comprising a second cooling passage segment and a third cooling passage segment, The first cooling passage segment is fluidly interposed between the second cooling passage segment and the third cooling passage segment. The first cooling passage segment, the second cooling passage segment, and the third cooling passage segment are all connected. The second cooling passage segment and the third cooling passage segment each have portions that are spatially fixed to the first portion of the support structure. The retaining collar is connected to one or more other components of the support structure such that the retaining collar is removable from the rest of the support structure without requiring the respective portions of the second cooling passage segment and the third cooling passage segment to move relative to the first portion of the support structure.

16. The system according to claim 15, wherein the retaining collar comprises two halves.

17. A system according to any one of claims 3 to 10, wherein the support structure further includes a support collar interposed between a portion of the seal collar and a portion of the retaining collar, the support collar having a plurality of mounting features arranged around its outer circumference.

18. A system according to any one of claims 1 to 10, Processing chamber and Shower head and Furthermore, The pedestal is positioned within the internal volume of the processing chamber. A system in which the first end of the stem is located within the internal volume of the processing chamber, and the second end of the stem is located outside the processing chamber.

19. The system according to claim 18, It further comprises a hexapod mechanism having a fixed base, a movable base, and six linear actuators, The support structure is attached to the movable base, The fixed base is attached to the processing chamber. Each of the first ends of the linear actuator is connected to the fixed base, A system in which the second end of each of the linear actuators is connected to the movable base.

20. A system according to claim 18, further comprising a vertical lift mechanism having a base portion and a movable portion, wherein the support structure is spatially fixed with respect to the movable portion, and the vertical lift mechanism includes one or more actuators configured to move the movable portion relative to the base portion in response to one or more input signals.

Images