Robotic arm with vacuum compatible seal and internal cooling flow path

Abstract

The present disclosure describes a robotic arm assembly for use in a vacuum environment. Such robotic arm assemblies may have one or more rotary joints with ferromagnetic fluid seals or other vacuum compatible seals. A coolant flow path section may be provided that passes through one or more of the one or more rotary joints to allow coolant to be circulated through one or more cooling features within the robotic arm assembly such that components within the robotic arm assembly, such as motors, ferromagnetic fluid seals, sensors, etc., are actively cooled.

Description

Related Applications

[0001] The PCT application form is filed concurrently with this specification as a part of this application. Each application identified in the concurrently filed PCT application form to which this application claims the benefit or priority is incorporated herein by reference in its entirety and for all purposes. Background Art

[0002] Semiconductor processing tools typically have a plurality of semiconductor processing chambers arranged around a vacuum transfer module (VTM). Such VTMs typically have one or more wafer handling robots, each of which has one or more robot arm assemblies that can be used to move one or more corresponding end effectors between different locations within or adjacent to the VTM, such as to transfer a wafer from one location to another. For example, such a wafer handling robot can be configured to move a wafer from one processing chamber connected to the VTM to another processing chamber connected to the VTM, or can be moved from a load lock or processing chamber connected to the VTM to a temporary storage station located within the VTM.

[0003] As the name implies, the interior of the VTM can typically be maintained under vacuum conditions, i.e., at a pressure below atmospheric pressure, so as to match or at least approach the pressure maintained by the processing chambers to which it is attached, thereby reducing the pressure difference between these processing chambers and the VTM, where the pressure difference must be restored after fluidly connecting one of the processing chambers to the VTM, for example by opening a valve or inlet and outlet that fluidly isolates one of the processing chambers from the VTM from each other.

[0004] This article discusses various modifications to robots that can be used in vacuum environments. Summary of the invention

[0005] The details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, drawings, and claims.

[0006] In some implementations, an apparatus may be provided that includes: a robot arm base; a robot arm assembly that includes one or more arm links and a first set of one or more revolute joints, each of the first set of one or more revolute joints including a corresponding vacuum compatible seal; a plurality of components that define a plurality of coolant flow path segments; and a first set of one or more cooling features, each of the first set of one or more cooling features being fluidly connected to at least two of the coolant flow path segments and having fluid interposed therebetween. A base revolute joint of the one or more revolute joints revolutely connects a first arm link of the one or more arm links to the robot arm base, and at least two of the coolant flow path segments may extend from the robot arm base through the base revolute joint and into at least the first arm link.

[0007] In some embodiments, the one or more vacuum-compatible seals may include at least a first vacuum-compatible seal, and the one or more cooling features may include one or more vacuum-compatible seal cooling features, wherein the one or more vacuum-compatible seal cooling features include a first vacuum-compatible seal cooling feature, and the first vacuum-compatible seal cooling feature is configured to cool the first vacuum-compatible seal when coolant flows into the first vacuum-compatible seal cooling feature via at least one of the coolant flow path segments and flows out of the first vacuum-compatible seal cooling feature via at least one other of the coolant flow path segments.

[0008] In some such implementations, the first vacuum-compatible seal cooling feature includes a channel extending through at least a portion of a tubular region, the tubular region having a centerline coaxial with an axis of rotation of one of the one or more rotational joints that includes the first vacuum-compatible seal, and the tubular region may surround one or more surfaces of the first vacuum-compatible seal, the one or more surfaces facing radially inwardly toward the axis of rotation of the one of the one or more rotational joints that includes the first vacuum-compatible seal.

[0009] In some implementations, the channel can be at least partially defined by one or more surfaces of the first vacuum compatible seal, the one or more surfaces facing radially outwardly away from the rotational axis of the one of the one or more rotational joints that includes the first vacuum compatible seal.

[0010] In some embodiments, the first vacuum-compatible seal cooling feature can include a channel extending through at least a portion of a tubular region, the tubular region having a centerline coaxial with an axis of rotation of one of the one or more rotational joints that includes the first vacuum-compatible seal, and the tubular region can be surrounded by one or more surfaces of the first vacuum-compatible seal that face radially inward toward the axis of rotation of the one of the one or more rotational joints that includes the first vacuum-compatible seal.

[0011] In some implementations, the channel can be at least partially defined by the one or more surfaces of the first vacuum compatible seal, the one or more surfaces facing radially inward toward the rotational axis of the one of the one or more rotational joints that includes the first vacuum compatible seal.

[0012] In some implementations, the channel can have an annular or annular sector shape.

[0013] In some embodiments, the robot arm assembly may include a first motor, and the one or more cooling features may include one or more motor cooling features, the one or more motor cooling features including a first motor cooling feature, the first motor cooling feature being disposed adjacent to or surrounding a portion of the first motor and configured to cool the first motor when coolant flows into the first motor cooling feature through at least one of the coolant flow path segments and flows out of the first motor cooling feature through at least one other of the coolant flow path segments.

[0014] In some embodiments, the one or more cooling features may include one or more arm link cooling features, the one or more arm link cooling features including a first arm link cooling feature, the first arm link cooling feature being disposed adjacent to or located in a material forming one of the one or more arm links, and the first arm link cooling feature being configured to cool the arm link when coolant flows into the first arm link cooling feature through at least one of the coolant flow path segments and flows out of the first arm link cooling feature through at least one other of the coolant flow path segments.

[0015] In some implementations, the first arm link cooling feature can extend along at least half of the length of the arm link, the first arm link cooling feature being disposed adjacent to or within the material of the arm link.

[0016] In some embodiments, the device may also include a first sensor located within one of the one or more arm links, the one or more cooling features may include one or more sensor cooling features, and the one or more sensor cooling features may include a first sensor cooling feature, which is arranged adjacent to or around a portion of the first sensor and is configured to cool the first sensor when coolant flows into the first sensor cooling feature through at least one of the coolant flow path segments and flows out of the first sensor cooling feature through at least one other of the coolant flow path segments.

[0017] In some implementations, the first sensor can be an optical sensor.

[0018] In some implementations, the first sensor can be an imaging sensor.

[0019] In some implementations, the one or more arm links may include a first end effector arm link having a first end effector, and the first sensor may be located in the first end effector arm link.

[0020] In some implementations, the first sensor can be positioned to collect data from a location below the first end effector arm link.

[0021] In some implementations, the first sensor can be positioned to collect data from a location above the first end effector arm link.

[0022] In some implementations, the first end effector arm link may also be the first arm link.

[0023] In some implementations, the device may further include a second sensor, the one or more arm links may further include a second end effector arm link, the second end effector arm link having a second end effector, the second sensor may be located in the second end effector arm link, the one or more arm links may further include a forearm link, the first end effector arm link may be rotatably connected to the forearm link via a first rotational joint of the one or more rotational joints, the second end effector arm link may be rotatably connected to the forearm link via a second rotational joint of the one or more rotational joints, and the one or more sensor cooling features may include a second sensor cooling feature, the second sensor cooling feature is arranged adjacent to or around a portion of the second sensor and is configured to cool the second sensor when coolant flows into the second sensor cooling feature via at least one of the coolant flow path segments and flows out of the second sensor cooling feature via at least one other of the coolant flow path segments.

[0024] In some implementations, the first rotational joint can be configured to enable the first end effector arm link to rotate relative to the forearm link about a first rotational axis, the second rotational joint can be configured to enable the second end effector arm link to also rotate relative to the forearm link about the first rotational axis, the first end effector can be disposed at a higher height than the second end effector, the first end effector arm link can include a first body portion and a first shaft portion, the first shaft portion can extend through the second end effector link, the first shaft portion can be supported by the first rotational joint, the first rotational joint includes a first vacuum compatible seal, the first vacuum compatible seal seals between the second end effector link and the first portion of the first end effector link, the second sensor and the second sensor cooling feature can both be located at a position within the second arm link, the position being located radially outward of the first vacuum compatible seal relative to the first rotational axis, and the first vacuum compatible seal can be between the first body portion and a position on the first shaft portion, wherein a plurality of coolant flow path segments leading to the second sensor cooling feature exit the first portion at the position.

[0025] In some implementations, an opening can extend through the first shaft portion across an arc segment about the first rotational axis, and the coolant flow path segment leading to the second sensor cooling feature can exit the first shaft portion via the opening.

[0026] In some such implementations, the sector of arc extends through at least 90 degrees.

[0027] In some implementations, the one or more arm links may include a plurality of arm links.

[0028] In some implementations, a second rotation joint can rotatably connect two of the plurality of arm links; at least two of the coolant flow path segments can pass through the base rotation joint, and at least two of the coolant flow path segments can pass through the second rotation joint.

[0029] In some implementations, at least some of the coolant flow path segments can be provided at least in part by flexible polymer tubing.

[0030] In some implementations, the components defining each flow path segment can include components selected from one or more of: a length of flexible polymer tubing, a length of rigid tubing, a flow-splitting device, a pass-through connector, and a fitting.

[0031] In some implementations, the apparatus may further include a purge gas exhaust feature. The purge gas exhaust feature may include one or more purge gas outlets fluidly connected to one or more purge gas plenums and configured to direct purge gas radially outward from the one or more purge gas plenums to the vicinity of a corresponding one of the one or more revolute joints. In addition, one or more purge gas lines may be arranged from the robot arm base through the base revolute joint and into at least the first arm link.

[0032] In some implementations, at least one of the one or more rotational joints can include a respective vacuum compatible seal that is a ferrofluid seal.

[0033] In some implementations, each rotary joint can include a respective vacuum compatible seal that is a ferrofluid seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In the following discussion, reference is made to the following drawings; the drawings are not intended to be limiting in scope but are provided merely to facilitate the following discussion.

[0035] Figure 1 A diagram of an exemplary wafer handling robot incorporating a rotary joint with a vacuum compatible seal and an active cooling system is depicted.

[0036] Figure 1A Depicted Figure 1Detailed view of a portion of the wafer handling robot indicated in frame A.

[0037] Figure 1B Depicted Figure 1 Detailed view of a portion of the wafer handling robot indicated in frame B.

[0038] Figure 1B' Describes the Figure 1 An alternative configuration implemented in a wafer handling robot.

[0039] Figure 1C Depicted Figure 1 Detailed view of a portion of the wafer handling robot indicated in frame C.

[0040] Figure 1C' Describes the Figure 1 An alternative configuration implemented in a wafer handling robot.

[0041] Figure 2 A diagram of an exemplary ferrofluid seal is depicted.

[0042] Figure 3 A diagram of an exemplary slew bearing is depicted.

[0043] FIG. 4A to FIG. 4C Schematic diagrams depicting different configurations of coolant flow path segments.

[0044] Figure 5 Depicted is a diagram of a VTM having multiple processing chambers attached thereto and containing a wafer handling robot disclosed herein.

[0045] The above-mentioned drawings are provided to facilitate understanding of the concepts discussed in the present disclosure and are used to depict some implementation schemes that fall within the scope of the present disclosure, but are not intended to be limiting - implementation schemes that conform to the present disclosure and are not depicted in the drawings are still considered to fall within the scope of the present disclosure. DETAILED DESCRIPTION

[0046] As previously mentioned, semiconductor processing tools typically include a vacuum transfer module (VTM), which may include one or more wafer handling robots having a robot arm assembly located within the VTM. Such a robot arm assembly typically includes at least one revolute joint that connects the robot arm assembly to a robot arm base that is fixed relative to the VTM (e.g., mounted on the bottom side of the VTM). The robot arm base may, for example, include one or more motors that can be actuated to rotate and / or raise and lower the robot arm assembly relative to the base. At a minimum, the wafer handling robot will have at least one revolute joint to allow its robot arm assembly to rotate relative to the robot arm base.

[0047] In many cases, a robot arm assembly included in a VTM may include multiple robot arm links, such as rigid links, connected end-to-end by respective revolute joints to allow each link to rotate relative to the other links or the links to which it is connected. For example, a robot arm assembly having three links may enable the endmost arm link to rotate about a robot arm base, move to any of a variety of positions about the robot arm base, and / or rotate relative to the other arm links, thereby providing greater flexibility in the locations where the robot arm assembly can transfer wafers. Thus, while some implementations of the concepts discussed herein may feature a robot arm assembly having only one revolute joint and one arm link, it should be understood that other implementations of the concepts discussed herein may feature a robot arm assembly having multiple revolute joints and multiple robot arm links.

[0048] Disclosed herein is a novel robot arm for use in a vacuum environment such as a VTM. By equipping each rotary joint in a robot arm assembly with a corresponding vacuum compatible rotary seal (e.g., a ferrofluid seal), the interior space of the robot arm assembly can be fluidly isolated from the vacuum environment while allowing the interior space of the robot arm link to be fluidly connected to, for example, the robot arm base. Through this fluid isolation, the interior space of the robot arm link can be maintained at a higher pressure, such as atmospheric pressure, than the vacuum environment surrounding the robot arm assembly. This can, for example, help cool various components that can be located inside the robot arm assembly, such as sensors, motors, bearings, etc. For example, sensors, motors, and bearings can all generate heat during use, such as heat generated by electrical resistance of electronic components, and heat generated by friction or rolling resistance in mechanical components. Such heat can be difficult to passively discharge, such as by thermal conduction of robot arm segments. Configuring the robot arm assembly to have sealed rotary joints allows the pressure inside the robot arm assembly to be maintained higher than the pressure of the vacuum environment in which the robot arm assembly is used, which, for example, allows the use of flexible polymer tubing to pass through these interior spaces of the robot arm assembly, such as through one or more rotary joints of the robot arm assembly. Such tubing may be used to define coolant flow path segments that may be used to circulate coolant through one or more cooling features that may be located near or within a component that requires cooling and that is located within one or more robot arm links. The use of such flexible tubing may allow flow paths to be arranged through rotary joints without the need for complex rotary joints with liquid transfer functions, such as rotary unions. The use of flexible tubing to direct fluids in vacuum environments (at least in vacuum environments with strict requirements on atmospheric purity, such as in semiconductor processing systems) is generally avoided because most such tubing is made of materials that may have outgassing problems and / or are not stiff enough to prevent the tubing from expanding when subjected to a vacuum environment and pressurized. Teflon may be one of the only candidates for such use, and even in this case, its use is generally discouraged due to the potential risk of leakage (either through the material itself or at the connection between the tubing and the fittings).

[0049] In addition, isolating the interior space of the robot arm assembly from the vacuum environment surrounding the robot arm assembly allows the use of components that may cause problems inside the robot arm assembly. For example, polymer pipes used for liquid transmission, polymer sheaths for cables or wires, adhesives, ball bearings, lubricants, etc. may generate contaminants, such as chemicals, dust or particles, which may cause serious contamination problems if they can leak into the vacuum environment. For example, particles that may be generated due to bearing friction wear in the interior of the robot arm assembly may be sucked into the vacuum environment and may stay on the wafer being transmitted through such an environment, thereby contaminating the wafer and potentially reducing the process yield. Similarly, gaseous substances that may be released from polymer components in the interior of the robot arm assembly may leak into the vacuum environment and may react with materials on the wafer being transmitted through the vacuum environment, thereby affecting the uniformity of the wafer and reducing the yield of the wafer. By including a ferrofluid seal or other vacuum-grade rotary interface in the robot arm assembly, the robot arm assembly can be sealed and isolated from the vacuum environment, so that contaminants from the interior of the robot arm assembly have little or no chance to migrate into the vacuum environment.

[0050] For example, the robot arm assembly described herein can be configured to actively cool components in any arm link of a multi-link robot arm assembly, thereby facilitating the placement of heat generating or heat sensitive features in the end-most arm link of such a robot arm assembly. For example, this can allow the placement of equipment, such as motors, bearings, seals, and / or sensors, in locations within such a robot arm assembly that are typically difficult to cool. In addition, it is often possible that a situation may arise where, for example, a wafer handling robot may need to retrieve or handle wafers that have elevated temperatures, such as 200°C or higher. These wafers may radiate thermal energy that may be absorbed by the end effector of the robot arm assembly, thereby contributing additional thermal energy to components in portions of the robot arm assembly that are thermally adjacent to the end effector.

[0051] Figure 1 A diagram of an exemplary wafer handling robot incorporating a rotary joint with a vacuum compatible seal and an active cooling system as described above is depicted. Figure 1 The three dashed rectangular areas are labeled "A", "B" and "C", each corresponding to Figure 1A , 1B and 1C range. Figure 1A , 1B and 1C can be understood to mean Figure 1 Detailed view of the portion of the wafer handling robot enclosed in each rectangular area.

[0052] It should be understood that Figure 1The wafer handling robot of is provided as an example robot, which is used to demonstrate a specific configuration of the robot arm assembly, such as having multiple arm links and multiple end effectors. However, it should also be understood that Figure 1 The concepts described in the wafer handling robot can also be applied to robot arm assemblies having more or fewer arm links (including only a single arm link) and / or more or fewer end effectors. In addition, Figure 1 The exemplary wafer handling robot of includes three different types of components with active cooling. It should be understood that other implementations may include only some of these components, or may include components that are different from those shown but are cooled in a similar manner.

[0053] It should also be understood that Figure 1 ; in some such cases, different instances of these components or features may be identified by the same callout number but with different lowercase suffixes, such as 100a, 100b, 100c, etc. It should be understood that these components may generally be referred to using only the numerical portion of these callouts, e.g., omitting the letter suffix, even though there may not be a specific callout consisting solely of the numbers in question. Furthermore, it should be understood that in some cases, the letter suffixes used for certain instances of components or features may not be consecutive, e.g., there may be instances 100c and 100d, but no instances 100a or 100b.

[0054] exist Figure 1, a cross-sectional view of a wafer handling robot 106 is depicted in FIG. The wafer handling robot 106 may include a robot arm base 108, and a robot arm assembly 110 supported by the robot arm base 108. The robot assembly 110 may include one or more arm links 116, in this example, the one or more arm links 116 include a first arm link 116a, a second arm link 116b, a third arm link 116c, a fourth arm link 116d, and a fifth arm link 116e. The robot arm assembly 110 may also include a group of one or more rotary joints 112. In this example, the group of rotary joints in the robot arm assembly 110 includes a first rotary joint 112a, a second rotary joint 112b, a third rotary joint 112c, a fourth rotary joint 112d, and a fifth rotary joint 112e. Each rotary joint 112 in the group of rotary joints 112 may include one or more rotary bearings 136 and a ferrofluid seal 124. It should be understood that although the present disclosure uses ferrofluid seals as vacuum-compatible seals in the examples below, other types of vacuum-compatible rotary seals may also be used, and the reference to "ferrofluid seal cooling features" may also be understood to be replaced by the reference to "vacuum-compatible seal cooling features". For example, a vacuum-compatible seal may be understood to provide a seal across a rotary interface that is sufficient to allow a vacuum, such as a vacuum in the range of 40 mTorr to 550 mTorr or less, to be maintained on one side of the seal while maintaining atmospheric pressure on the other side of the rotary interface. In some cases, a vacuum-compatible seal may include a sliding seal, such as a sliding contact between a compliant sealing structure (e.g., an elastomeric seal) and a sealing surface (e.g., a shaft). In other cases, a vacuum-compatible seal may include a non-sliding seal, such as a non-sliding contact between two structures at a sealing interface. In such a vacuum-compatible seal, a sealing element may be provided, for example, by a fluid material, such as a ferrofluid, to eliminate friction between discrete components of the sealing interface and reduce particle generation.

[0055] The rotation bearings 136 may be, for example, ball bearings, or other bearings that may allow one arm link 116 to rotate relative to another or the robot arm base. In this example, the rotation bearings 136 each include an inner race 138a, an outer race 138b, and a plurality of ball bearings 140 therebetween, such as Figure 3 An exemplary slew bearing is shown.

[0056] The ferrofluid seal 124 is a seal that can be used to provide a vacuum compatible seal across a rotating interface between two components that are configured to rotate relative to each other. Figure 2As shown, a typical ferrofluid seal may include two roughly annular pole pieces 127a and 127b having coaxial center lines and spaced apart from each other along these center lines. Pole piece 127 may be made of a ferrous material, such as iron, for example. An annular array of magnets 126 may be inserted between the two pole pieces 127 so that the polarities of the magnets 126 face the same direction, for example, the N pole of each magnet may be magnetically clamped to pole piece 127a, and the S pole of each magnet may be magnetically clamped to pole piece 127b. In some cases, a single annular magnet 126 may be used instead of the annular array of magnets 126.

[0057] The magnetic core 128 may be positioned to pass through the pole piece 127. For example, the magnetic core 128 may have a centerline that is coaxial with the centerline of the pole piece 127. The magnetic core 128 may be supported relative to the pole piece 127 by one or more rotating bearings such that the magnetic core 128 is concentric with the inner surface of the pole piece 127 and there is a slight radial gap between the outermost surface of the magnetic core 128 and the radially inwardly facing surface of the pole piece 127 in the region axially overlapping the pole piece 127. The magnetic core 128 may include a plurality of circumferential grooves or grooves along a length portion axially overlapping the pole piece 127, so that a plurality of circumferential ridges or corrugations are adjacent to the pole piece 127. The magnetic field provided by the magnet 126 may generate a somewhat annular magnetic flux region, wherein a magnetic flux band enters the pole piece 127a from the magnet 126 and then crosses the gap between the magnetic core 128 and the pole piece 127a. The flux band then travels along the core 128 and then jumps back across the gap through the pole piece 127b before returning to the magnet 126.

[0058] The flux intensity in the gap at each circumferential "ridge" location will naturally be stronger than the "valleys" between these circumferential "ridges". When the ferrofluid 130 is introduced into the gap between the pole piece 127 and the core 128, the ferrofluid will naturally accumulate in the radial gaps between the circumferential ridges and the pole piece 127 due to the higher flux in these areas. This will create a series of ferrofluid barriers that span the gap, for example from the pole piece 127 to the core 128. Each barrier can act as a seal, so in effect the ferrofluid 130 provides a series of circumferential seals. When faced with a vacuum environment, these ferrofluid seals as a whole can form a leak-proof (or sufficiently leak-proof) interface between the core 128 and the pole piece 127, thereby allowing the core 128 and the pole piece 127 to rotate relative to each other while preventing gas from leaking therefrom. Furthermore, since the ferromagnetic fluid 130 is magnetic, particle debris that may be generated by the ferromagnetic fluid 130 will tend to be trapped between the pole piece 127 and the magnetic core 128, thereby reducing or eliminating the possibility of particles from the rotary joint 112 contaminating the interior of the VTM.

[0059] In some ferrofluid seals, the magnetic core 128 and the pole piece 127 may be in reverse positions, ie, the magnetic core 128 surrounds the pole piece 127 rather than the pole piece 127 surrounding the magnetic core 128 .

[0060] In addition, in some ferrofluid seals, the ferrofluid seal may include one or more cooling cavities through which coolant can flow to cool the ferrofluid seal. For example, the core 128 may have an annular channel located in the innermost surface of the core 128 (or the outermost surface if the core surrounds the pole piece 127). Therefore, when the shaft is inserted through the hole in the center of the core 128, an annular cavity 134 can be defined by the annular channel and the outer surface of the shaft that delimits the shaft. O-rings 1A, 132a and 132b (or other suitable seals) can be used to seal the core 128 to the shaft and prevent axial leakage of coolant from the cavity 134. The inlet and outlet can be fluidly connected to the cavity 134 and, for example, located diametrically opposite to each other to allow coolant to flow into the cavity 134, pass through the cavity 134, and then flow out of the cavity 134.

[0061] Returning to the wafer handling robot 106, one of the one or more rotary joints 112 can serve as a base rotary joint for rotatably connecting one of the arm links 116 to the robot arm base 108. In this example, the first rotary joint 112a serves as a base rotary joint. In an implementation with multiple arm links 116, each arm link 116 can be rotatably connected to another arm link 116 via a corresponding rotary joint 112. For example, in the depicted exemplary robot arm assembly 110, the first arm link 116a is rotatably connected to the second arm link 116b via the second rotary joint 112b, and the second arm link 116b is rotatably connected to the third arm link 116c via the third rotary joint 112c. The fourth arm link 116d and the fifth arm link 116e are both rotatably connected to the third arm link 116c via the fourth rotary joint 112d and the fifth rotary joint 112e, respectively. In this example, the fourth rotation joint 112d and the fifth rotation joint 112e are coaxial with each other, so that the fourth arm link 116d and the fifth arm link 116e can both rotate relative to the third arm link 116c about a common rotation axis.

[0062] One or more of the arm links 116 of the robot arm assembly 110 may serve as an end effector link, which terminates, for example, in an end effector 176, which may be used to support a semiconductor wafer (or other item) being transported by the robot arm assembly 110. In the exemplary robot arm assembly 110, there are two end effector arm links, with the fourth arm link 116d (supporting the first end effector 176a) serving as the first end effector arm link and the fifth arm link 116e (supporting the second end effector 176b) serving as the second end effector arm link. In some cases, the end effector link may be connected to another arm link that directly supports the end effector link relative to the rest of the robot arm assembly. The arm link that directly supports the end effector link may be referred to as a "forearm link". It will be appreciated that in some cases, the robot arm assembly may feature a single arm link, in which case the end effector arm link may be directly connected to the robot arm base 108.

[0063] The various arm links 116 shown are each capable of being independently driven using a corresponding motor 162, but in certain multi-link robotic arm assemblies, two or more of these arm links may be kinematically coupled so that they move together in a kinematically linked manner, thereby allowing both arm links to move relative to the corresponding arm link supporting them in response to a single power input (e.g., a rotational input from a single motor).

[0064] For example, Figure 1A As more clearly shown in FIG. 1 , the first arm link 116a includes a first motor 162a including a first stator 164a and a first rotor 166a. The first rotor 166a can be connected to a shaft that protrudes upward from the robot arm base 108 and is fixed in place relative to the robot arm base 108. The first stator 164a can be connected to the first arm link 116a so that when the first motor 162a is powered, the first rotor 166 and the first stator 164a can rotate relative to each other, thereby rotating the first arm link 116a relative to the robot arm base 108. Of course, the configuration shown can also be reversed, such as the first motor 162a is located in the robot arm base 108, and the shaft extends downward from the first arm link 116a and enters the robot arm base 108 and the first motor 162a.

[0065] like Figure 1AAs shown, the first arm link 116a can also include a second motor 162b, which includes a second stator 164b and a second rotor 166b. The second stator 164b can be fixed in place relative to the first arm link 116a, and the second rotor 166b can be fixed in place relative to the second arm link 116b. For example, the second arm link 116b can have a shaft that extends downward into the second arm link 116b and the second rotor 166b. When the second motor 162b is actuated and causes the second stator 164b and the second rotor 166b to rotate relative to each other, the generated rotational output can cause the second arm link 116b to rotate relative to the first arm link 116a.

[0066] As shown, the first rotary joint 112a may include a pair of rotary bearings 136a and 136a' that may rotatably support the first arm link 116a relative to the robot arm base 108. The first rotary joint 112a may also include a ferrofluid seal 124a that may seal the first arm link 116a from the shaft protruding from the robot arm base 108. It should be noted that the rotary bearings 136a and 136a' are sealed within the first arm link 116a by the ferrofluid seal 124a.

[0067] like Figure 1A As more clearly shown in , the two coolant flow path segments 120a and 120b are routed from the robot arm base 108 through the first rotary joint 112a and into the first arm link 116a. For example, the shaft extending upward from the robot arm base 108 and entering the first arm link 116a may have a hole or channel passing through it, and the coolant flow path segments 120a and 120b may be routed through the hole or channel. There may be a gap between the inner surface of the end of the shaft of the first arm link 116a facing the robot arm base 108 to allow the coolant flow path 120 to be routed to a component or location located radially outside the first rotary joint 112a. One or more of these coolant flow paths 120a can be fluidly connected to the coolant source 194, and one or more of these coolant flow paths 120b can be fluidly connected to the coolant circuit 196. Alternatively, coolant flow paths 120a and 120b may be fluidly connected to, for example, an external heat exchanger or coolant storage tank and a pump that circulates coolant from the heat exchanger or storage tank through the coolant flow path segments and then back to the heat exchanger or storage tank. Available coolants may include, for example, water, water mixed with antifreeze, Galden, or other suitable liquids.

[0068] Similarly, one or more cables 118 may also be routed through the first rotary joint 112a. The one or more cables 118 may be electrical cables for transmitting electrical signals, such as power and / or data signals, to components within the robot arm assembly 110. The one or more cables 118 may be connected to a controller 198, which may provide power and / or data signals to control the wafer handling robot.

[0069] The coolant flow path 120 can generally be configured to route the coolant fluid to one or more cooling features that can be located within the robot arm assembly. For example, the ferrofluid seal 124a can have a first ferrofluid seal cooling feature 144a adjacent to or surrounding the ferrofluid seal 124a. In this example, the first ferrofluid seal cooling feature 144a includes an annular cavity that extends around the outer periphery of the ferrofluid seal 124a and is partially defined by it. For example, the first ferrofluid seal cooling feature 144a can, for example, have an input port feature and an output port feature, the input port feature can receive coolant transmitted to the first ferrofluid seal cooling feature 144a by one of the coolant flow path segments 120a, and the output port feature can transmit coolant from the first ferrofluid seal cooling feature 144a to one of the coolant flow path segments 120a. Thus, the coolant flow path segments 120a and 120b may be used to flow coolant through the first ferrofluid seal cooling feature 144a, thereby cooling the ferrofluid seal 124a.

[0070] As shown, the first ferrofluid seal cooling feature 144a is an annular gap surrounding the ferrofluid seal 124a. In this case, the annular gap is defined by an annular channel in the outer surface of the magnetic core of the ferrofluid seal 124a and another annular channel in the inner surface of the hole in the first arm link 116a receiving the ferrofluid seal 124a. However, other implementations may be characterized by channels in one of these positions or other positions. In addition, other configurations of ferrofluid seal cooling features may also be used, such as C-shaped cooling features, in which the input port and the output port are located at opposite ends of the C-shaped channel surrounding or mostly surrounding the ferrofluid seal. In general, the ferrofluid seal cooling feature may include at least one or more channels, such as C-shaped or annular fan-shaped channels, two C-shaped channels forming an annular channel, etc., which are at least partially located in a tubular region having a central axis coaxial with the axis of rotation of the rotary joint of the ferrofluid seal involved. In some cases, such a tubular region may surround one or more surfaces of the ferrofluid seal being cooled that face radially inwardly toward its axis of rotation. In other cases, the tubular region may instead be surrounded by one or more surfaces of the ferrofluid seal being cooled that face radially inwardly toward its axis of rotation. In other implementations, such a channel may simply be located next to the ferrofluid seal being cooled. In certain implementations, at least a portion of such a channel may be defined by surfaces of the ferrofluid seal being cooled, such as radially outward or radially inward surfaces of the ferrofluid seal, depending on the positioning of the ferrofluid seal cooling feature relative to the ferrofluid seal being cooled.

[0071] Similar to the first rotary joint 112a, the second rotary joint 112b has a pair of rotary bearings 136b and 136b', which can rotatably support the second arm link 116b relative to the first arm link 116a. The second rotary joint 112b can also include a second ferromagnetic fluid seal 124b, which can seal between the first arm link 116a and the shaft protruding from the second arm link 116b. The second ferromagnetic cooling feature 144b that is fluidly connected to the two coolant flow path sections 120 and the fluid is between the two coolant flow path sections 120 is positioned to provide cooling to the second ferromagnetic fluid seal 124b.

[0072] It should be understood that in this example, the other rotary joints 112c, 112d, and 112e are also equipped with corresponding ferrofluid cooling features, thereby allowing the ferrofluid seals of each rotary joint 112 to be actively cooled through their dedicated ferrofluid seal cooling features 144. In some implementations, ferrofluid seals 124 disposed adjacent to each other, such as ferrofluid seals 124d and 124e, can share a common ferrofluid seal cooling feature, such as these ferrofluid seals can be close enough so that heat from one ferrofluid seal can flow through the other ferrofluid seal to reach the ferrofluid seal cooling feature surrounding both of them.

[0073] In general, the cooling features discussed herein, such as the ferrofluid seal cooling features 144, can each be fluidly connected to at least two coolant flow path segments and fluidly interposed between the at least two coolant flow path segments, so that coolant can be delivered to the cooling feature via one of the coolant flow path segments and then discharged from the cooling feature via one or more of the other coolant flow path segments. Each coolant flow path segment 120 can be defined, for example, by one or more components, such as a length of flexible tubing (e.g., polymer tubing), a length of rigid tubing, a fitting, a straight-through connector (or a portion thereof), and a flow-dividing device (or a portion thereof).

[0074] As can be seen in this example, there are multiple coolant flow path segments 120a and 120b, where coolant flow path segment 120a provides coolant delivery to various cooling features used, while coolant flow path segment 120b provides coolant circuits from these same cooling features. In this example, the various coolant flow path segments 120a and 120b are each fluidly connected to a corresponding junction block 122, which allows the coolant flow to be subdivided or split between different coolant flow path segments 120a, or allows the coolant flow from different coolant flow path segments 120b to be merged or joined. Such junction blocks 122 are configured in the robot arm assembly 110 so that these junction blocks 122 are all connected in series by corresponding coolant flow path segments 120a and 120b, wherein additional coolant flow path segments 120 lead from each junction block 122 to nearby cooling features, thereby supplying coolant to these cooling features in parallel.

[0075] It can be seen that another pair of coolant flow path segments 120 pass from the first arm link 116a to the second arm link 116b via the second rotation joint 112b. Such coolant flow path segments 120 may, for example, pass upward through a hollow shaft extending downward from the second arm link 116b into the first arm link 116a.

[0076] The second arm link 116b is shown in more detail at Figure 1B . It can be seen that the second arm link 116b has a different motor configuration inside, wherein the third motor 162c (which is represented by a block, but which, like the first motor 162a and the second motor 162b, typically includes a rotor and a stator) is configured to provide a rotational input to the third arm link 116c via a pulley system. For example, the third motor 162c may have a rotational output connected to a pulley 168c, which in turn is coupled to a pulley 168c' motion by a belt 170c. The belt 170c may be, for example, a steel belt. Steel belts are typically used for robot arm assemblies used in a vacuum because such belts do not deflate and only produce very small amounts of particulate contaminants. However, since the interior of the second arm link 116b is fluidly isolated from the vacuum environment surrounding the robot arm assembly 110 by a ferrofluid seal 124, other types of materials that are typically avoided in robots designed for a vacuum environment may also be used for the belt 170c, such as polymer belts, textile reinforced polymer belts, and the like. Note that there is no pulley 168a or pulley 168b in the depicted exemplary robotic arm assembly 110; the omission of the a / b suffixes is intentional to allow pulleys 168c and 168c' to share the same suffix with their associated motors 162.

[0077] When third motor 162c is actuated, for example in response to power and / or control signals received via cable 118, rotation of pulley 168c causes belt 170c to drive pulley 168c', thereby causing third arm link 116c to rotate relative to second arm link 116b.

[0078] It can be seen that the third rotary joint 112c includes a pair of rotary bearings 136c and 136c' like the aforementioned rotary joint 112, which support the third arm link 116c relative to the second arm link 116b, for example, through a shaft protruding from the lower side of the third arm link 116c. The third rotary joint 112c also includes a third ferrofluid seal 124c, which seals between the third arm link 116c (for example, at the shaft protruding from the lower side of the third arm link 116c) and the second arm link 116b, thereby sealing the interior of the second arm link 116b and preventing potential leakage through the third rotary joint 112c.

[0079] Also shown is a third ferrofluid seal cooling feature 144c configured to cool the third ferrofluid seal 124c. The third ferrofluid seal cooling feature 144c can be, for example, similar to the aforementioned ferrofluid seal cooling feature 144, and can be fluidly connected to, for example, coolant flow path segments 120a and 120b leading to the second joint block 122b (where the first joint block is the joint block 122a).

[0080] In addition to the third ferrofluid seal cooling feature 144c, the second arm link 116b also includes another type of cooling feature, such as a third motor cooling feature 146c (in this example, there is no first or second motor cooling feature, and the "third" ordinal indicator is used to make the motor cooling feature share the same ordinal indicator as the motor it cools). The third motor cooling feature 146c can be positioned adjacent to or around the third motor 162c, and can be, for example, a cooling jacket, such as a housing that can contact the motor and surround some or all of its circumference, and it can have one or more internal cavities through which coolant supplied from one of the coolant flow path segments 120 can flow to remove heat from the third motor cooling feature 146c, thereby cooling the third motor 162c. The cooling jacket can, for example, be similar in structure to the aforementioned ferrofluid seal cooling feature 144, such as having a similarly structured internal cavity or channel. It should also be appreciated that the ferrofluid seal cooling features 144 may be provided in a separate portion, such as a cooling jacket similar to that providing the third motor cooling feature 146c, rather than being integrated into the structure of the arm link 116 in which they are contained.

[0081] As shown, coolant may flow into the third motor cooling feature 146 c through one or more coolant flow path segments 120 and then flow out of the third motor cooling feature 146 c through one or more other coolant flow path segments 120 .

[0082] In some implementations, such as the alternative Figure 1B As shown, the use of ferrofluid seals or other vacuum-grade rotary seals can be used in conjunction with additional fluid flow lines for purposes other than cooling or to supplement cooling. For example, in some implementations, one or more fluid flow lines for providing a purge gas, such as an inert gas (an inert gas or other gas that is non-reactive with the process chemicals, such as nitrogen in many cases) can be routed inside the robot arm assembly.

[0083] exist Figure 1B', the second rotary joint 112b has an expanded purge gas discharge feature that allows the purge gas provided by the purge gas line 184 to be provided to a purge gas plenum 186, which can then distribute the purge gas to one or more purge gas outlets 188 disposed around or around the second rotary joint 112b. The purge gas plenum 186 can, for example, be generally annular in shape, or otherwise extend around most or all of the circumference of the second rotary joint (e.g., the purge gas plenum can be composed of two arcuate plenums / channels having a common center point and each providing purge gas from a corresponding inlet). Similar to the coolant flow path segment, the purge gas line 184 can be at least partially composed of flexible tubing.

[0084] Figure 1B The three circular cross-sections shown in the lower right corner of the ' depict various alternative implementations of the sweep gas exhaust feature. The example on the left is similar to Figure 1B 'The example shown on the far left is similar, having a plurality of dispersed purge gas outlets 188 arranged in a circular array around the exterior of the shaft portion of the second arm link 116b, such that the purge gas is caused to flow radially outward around the circumference of the shaft portion in the gap between the first arm link 116a and the second arm link 116b near the second rotational joint 112b when flowing into the purge gas plenum 190. This purge gas flow can protect the second ferrofluid seal 124b from possible exposure to process gas residues that might otherwise come into contact with and potentially degrade the second ferrofluid seal 124b.

[0085] exist Figure 1B The intermediate cross section shown is similar in design, except that instead of the purge gas outlet 188 being provided by a plurality of discrete passages disposed about the shaft portion of the second arm link 116b, there is a single purge gas outlet 188 provided by a thin circumferential slit spanning between the exterior of the shaft portion of the second arm link 116b and the purge gas plenum 186.

[0086] exist Figure 1B The right cross section shown in ' is designed to be Figure 1BThe leftmost circular cross section is similar except that it has multiple purge gas plenums 186 and multiple different sets of purge gas outlets 188. For example, purge gas can be provided to the first purge gas plenum 186a through the purge gas line 184, and then the purge gas is transferred from the first purge gas plenum 186a to the second purge gas plenum 186b through the first purge gas outlet 188a. The purge gas can then be transferred from the second purge gas plenum 186b to the area around the shaft portion of the second arm link 116b through the second purge gas outlet 188b.

[0087] As can be seen, the use of a plurality of purge gas plenums 186 (each plenum region having an annular plenum or a plurality of arcuate plenums within an annular region) arranged to provide more or less concentric purge gas plenum regions in fluid communication with one another through purge gas outlets each spanning between two adjacent purge gas plenums allows the purge gas delivered thereto to be more evenly distributed circumferentially between the last set of purge gas outlets before being released into the environment surrounding the robot arm assembly. In this arrangement, each set of purge gas outlets communicating between two adjacent purge gas plenum regions can be disposed at equidistant circumferential locations between two adjacent purge gas outlets 188, thereby bringing each possible shortest flow path between the purge gas inlet and each outermost purge gas outlet 188 closer to the average flow path length, thereby achieving a more evenly distributed purge gas.

[0088] It should be understood that although the above-mentioned purge gas exhaust feature is only shown as being implemented on the second rotary joint 112b, similar features can be implemented on any rotary joint of the robot arm assembly, including all rotary joints of the robot arm assembly or at least multiple rotary joints of the robot arm assembly.

[0089] Figure 1C A detailed view of the third arm link 116c, the fourth arm link 116d, and the fifth arm link 116e is depicted. The third arm link 116c includes a fourth motor 162d and a fifth motor 162e, which are shown as being movably connected to the fourth arm link 116d and the fifth arm link 116e, respectively. For example, the fourth motor 162d can be configured to drive a pulley 168d through a belt 170d, which is configured to drive a pulley 168d' through a belt 170d', thereby rotating the fourth arm link 116d relative to the third arm link 116c. Similarly, the fifth motor 162e can be configured, for example, to drive a pulley 168e through a belt 170e, which is configured to drive a pulley 168e' through a belt 170e', ​​thereby rotating the fifth arm link 116e relative to the third arm link 116c.

[0090] like Figure 1 and 1C As shown, fourth and fifth motor cooling features 146d, 146e may be positioned to surround or be adjacent to fourth and fifth motors 162d, 162e, respectively. These motor cooling features may, for example, have features similar to those of third motor cooling feature 146c described above.

[0091] As described above, the fourth arm link 116d and the fifth arm link 116e can establish a rotatable connection with the third arm link 116c through the fourth rotation joint 112d and the fifth rotation joint 112e, respectively.

[0092] As can be seen, like the aforementioned rotary joint 112, the fourth rotary joint 112d includes a pair of rotary bearings 136d and 136d', which are used to support the fourth arm link 116d relative to the third arm link 116c, for example, through the shaft portion 178d protruding from the bottom side of the main body portion 180d of the fourth arm link 116d. The fourth rotary joint 112d also includes a fourth ferrofluid seal 124d, which seals the fourth arm link 116d, for example, the shaft portion 178d protruding from the bottom side of the main body portion 180d of the fourth arm link 116d and the shaft portion 178e protruding from the bottom side of the main body portion 180e of the fifth arm link 116e, thereby sealing the interior of the third arm link 116c and preventing potential leakage through the fourth rotary joint 112d. Likewise, the fifth rotary joint 112e includes a pair of rotary bearings 136e and 136e', which are used to support the fifth arm link 116e relative to the third arm link 116c, for example, by a shaft portion 178e protruding from the bottom side of the main body portion 180e of the fifth arm link 116e. The fifth rotary joint 112e also includes a fifth ferrofluid seal 124e, which seals the fifth arm link 116e, for example, the shaft portion 178e protruding from the bottom side of the main body portion 180e of the fifth arm link 116e, and the third arm link 116c, thereby sealing the interior of the third arm link 116c to prevent potential leakage through the fifth rotary joint 112e.

[0093] As previously described, the fourth rotary joint 112d and the fifth rotary joint 112e are coaxially arranged. Therefore, the shaft portion 178d actually extends through the shaft portion 178e and protrudes beyond the end of the shaft portion 178e, thereby allowing the shaft portion 178d to be connected to the pulley 168d'. The shaft portion 178e is rotatably supported relative to the third arm link 116c by the rotary bearings 136e and 136e', and the shaft portion 178d is rotatably supported relative to the shaft portion 178e by the rotary bearings 136d and 136d'. Since the rotary bearings 136d, 136d', 136e and 136e' are all positioned to have a common rotation axis, such an arrangement effectively allows the fourth arm link 116d and the fifth arm link 116e to rotate relative to the third arm link 116c and relative to each other through the fourth rotary joint 112d and the fifth rotary joint 112e, respectively.

[0094] like Figure 1 and 1C As shown, the fourth arm link 116d and the fifth arm link 116e respectively accommodate respective sensors 172a and 172b. These sensors 172 can be optical sensors, such as imaging sensors. Each sensor 172 can be configured to acquire data, such as an image, from the area below it. For example, such a sensor 172 can be used to acquire image data about a component within a semiconductor processing chamber, such as an image of a reference point located on the component, which can assist in calibrating the robot arm system in terms of the position of the component relative to the robot arm base 108. Such a sensor can also be used to acquire data on other aspects of the room, such as the state of the base or edge ring within the room. It should be understood that the sensor 172 can also or additionally be placed in other orientations within the robot arm links 116d and 116e, such as upward or outward instead of downward. Such a configuration allows the sensor 172 to acquire data about components or features such as chamber walls or nozzles that may be located within the processing chamber.

[0095] exist Figure 1 and 1C 148a and 148b. The sensor cooling features 148 can be respectively arranged to be adjacent to or surround a portion of one of the sensors 172. In this example, the sensor cooling features 148a and 148b are cooling blocks and have a serpentine cooling passage therethrough. The cooling blocks are arranged against the sensors 172 so that the heat of the sensors 172a and 172b is conducted into the sensor cooling features 148a and 148b, respectively. The coolant flowing through the sensor cooling features 148 can then be used to remove heat from the sensor cooling features 148.

[0096] In e.g. Figure 1 and 1CIn the coaxial revolute configuration shown, it may be challenging to route coolant flow path segments for cooling features that may be located within the arm link 116 supported by the coaxial revolute 112. For example, the coolant flow path segments 120 may be routed through the center of the shaft portion 178d, then out of the top of the shaft portion 178d and into the interior of the fourth arm link 116d, thereby leading to the fourth arm link 116d, where these coolant flow path segments 120 may be fluidly connected to the cooling features. However, routing coolant flow path segments to cooling features located within the fifth arm link 116e may be more challenging. For example, if these coolant flow path segments also pass through the center of the shaft portion 178d, they will need to pass through the fifth revolute in a radial direction (rather than an axial direction) to reach the interior of the fifth arm link 116e.

[0097] To facilitate this operation, the shaft portion 178d can be provided with an opening (or a plurality of openings) extending in a generally radial manner from the interior of the shaft portion 178d to the exterior surface of the shaft portion 178d, thereby allowing the coolant flow path segment 120 to be routed from the interior of the shaft portion 178d to the exterior of the shaft portion 178d. The opening, for example Figure 1C The opening 182 in the can be arranged so that a ferrofluid seal that seals between the two coaxial shaft portions 178d and 178e is interposed between the opening 182 and the main body of the fourth arm link 116d. This allows the opening to be located in an area of ​​the robot arm assembly 110 that is fluidly isolated from the vacuum environment that may surround the robot arm assembly 110. This allows the coolant flow path segment 120 to enter the fifth arm link 116e from the interior of the shaft portion 178d of the fourth arm link 116d.

[0098] In some cases, the opening 182 can extend an arc segment around the circumference of the shaft portion, for example, the opening 182 can be a radial slot that extends along an arc that is coradial with the outer surface of the shaft portion 178d, for example, through an arc angle of at least 45°, at least 60°, at least 75°, at least 90°, at least 115°, at least 130°, or at least 180°. Such a slot can provide clearance to allow the shaft portion 178d and the shaft portion 178e to rotate relative to each other without causing excessive shear stress in the coolant flow path segment 120 passing through the opening 182. The arc segment that the opening extends across can be selected, for example, to be generally similar to the arc segment that the fourth arm link 116d and the fifth arm link 116e can swing relative to each other during normal use.

[0099] Figure 1CAn alternative implementation is depicted that includes an additional type of cooling feature—an arm link cooling feature. Figure 1C 'What is shown, its display Figure 1C In a detailed view of the area marked C' in FIG. 1 , the fourth arm link 116d is equipped with an arm link cooling feature 151. In this example, the arm link cooling feature 151 is a cooling block having one or more cooling channels therein that provide coolant from corresponding coolant flow path segments 120a and 120b. As shown, these cooling channels can extend along a serpentine path within the cooling block. In other implementations, such cooling channels can be formed directly in the material of the arm link itself, such as by machining. The arm link cooling feature 151 can, in some cases, extend along the entire length of the arm link, or can extend along only a portion thereof, such as along half of the arm link closest to the end effector. The arm link cooling feature 151 can also extend along the bottom surface and / or side surface of the arm link.

[0100] It should be understood that although Figure 1C The arm link cooling feature 151 is shown in only a single arm link, but such an arm link cooling feature may also be implemented in additional or other arm links, such as in all arm links or a subset thereof. Such a cooling feature may allow a robotic arm assembly to dissipate heat that may be transferred to its components, such as by handling high temperature wafers. For example, if a robotic arm assembly is used to pick up wafers that are still hot, such as at 200+°C, 300+°C and / or 400+°C, then the heat radiated and conducted from these wafers may be transferred via conduction to the end effector carrying them and then to the arm link. Because such robotic arm assemblies typically operate in a vacuum environment, it may be difficult for the robotic arm assembly to dissipate the heat transferred thereto to the surrounding atmosphere. Therefore, the arm link cooling feature may provide a valuable capability to cool a robotic arm assembly used in a vacuum environment and used to transfer hot wafers.

[0101] It should be understood that the above Figures 1 to 1C The various cooling features and features of the components to be cooled within the robot arm assembly described above may be implemented in a variety of situations. For example, some robot arm assemblies may include only ferrofluid seal cooling features, while other robot arm assemblies may include only sensor cooling features. The robot arm assembly need not have the features described above with respect to Figures 1 to 1CAll four types of cooling features within the described robotic arm assemblies, including only ferrofluid seal cooling features, only motor cooling features, only sensor cooling features, only arm link cooling features, only ferrofluid seal cooling features and motor cooling features, only ferrofluid seal cooling features and arm link cooling features, only ferrofluid seal cooling features and sensor cooling features, only motor cooling features and arm link cooling features, only sensor cooling features and arm link cooling features, only ferrofluid seal cooling features, motor cooling features and sensor cooling features, only ferrofluid seal cooling features, motor cooling features and sensor cooling features, only ferrofluid seal cooling features, motor cooling features and arm link cooling features, only ferrofluid seal cooling features, sensor cooling features, sensor cooling features or arm link cooling features, and only motor cooling features, sensor cooling features or arm link cooling features are also considered to fall within the scope of the present disclosure. It should also be understood that cooling features other than the specific examples discussed herein may also be included in such a robot arm assembly. Figures 1 to 1C The concepts discussed in connection with the exemplary robotic arm assembly 110 may also be implemented in a robotic arm assembly having only a single arm link, two arm links, three arm links, four arm links, five arm links, six arm links, seven arm links, eight arm links, nine arm links, etc. It should also be understood that other vacuum compatible seals may be used in addition to the ferrofluid seals discussed herein, if desired.

[0102] The above discussion refers to coolant flow path segments, and generally does not distinguish between inlet coolant flow path segments and outlet coolant flow path segments. This is because the properties of any particular coolant flow path segment may vary, depending on the context in which it is observed. For example, in Figures 1 to 1C In the example of , coolant flow path segments 120a may all be used to supply coolant to various cooling features within the depicted robot arm assembly 110, while coolant flow path segments 120b may all be used to recover coolant from the same cooling features (or vice versa). Figures 1 to 1C In the example of FIG. 1 , coolant flow path segment 120a is arranged generally in parallel with coolant flow path segment 120b, so that each coolant flow path segment 120 serves only one purpose, namely supplying coolant to a cooling feature or returning coolant from a cooling feature. However, other arrangements, such as delivering coolant to multiple cooling features in sequence, can allow the coolant flow path segments to serve multiple purposes, such as a single coolant flow path segment can be used as a coolant supply source for a cooling feature located "downstream" of the coolant flow path segment, and as a coolant return for another cooling feature located "upstream" of the coolant flow path segment.

[0103] Figure 4, including Figure 4A , Figure 4B and Figure 4C , a diagram depicting various coolant flow path segment routing options that may be used to provide coolant to and receive coolant from cooling features of a robotic arm assembly.

[0104] In FIG4 , an exemplary robot arm assembly 410 is shown. The exemplary robot arm assembly 410 includes a first arm link 416a, a second arm link 416b, a third arm link 416c, and a fourth arm link 416d. The first arm link 416a is rotatably connected to a robot arm base (not shown) via a first rotary joint 412a, and is rotatably connected to the second arm link 416b via a second rotary joint 412b. Similarly, the third arm link 416c is rotatably connected to the second arm link 416b via a third rotary joint 412c, and is rotatably connected to the fourth arm link 416d via a fourth rotary joint 412d. Multiple cooling features 442 are provided at different locations inside the robot arm assembly 410, including, for example, a first cooling feature 442a and a second cooling feature 442b located in the first arm link 416a, a third cooling feature 442c located in the second arm link 416b, and a fourth cooling feature 442d located in the third arm link 416c.

[0105] In FIG. 4 , coolant flow path segments are represented by lines with triangles indicating flow direction, which connect to various cooling features and are routed through revolute joint 412 .

[0106] exist Figure 4A 4, a single coolant flow path segment can be seen to be fluidly connected to the inlet of cooling feature 442d and through three rotational joints 412a to 412c. It can also be seen that additional coolant flow path segments fluidly connect the outlets of each of the three cooling features 442d-442b to the inlet of their "downstream" cooling features 442c-442a. The coolant flow path segment derived from the outlet of the first cooling feature 442a can, for example, exit the robot arm assembly 410 through the robot arm base and be discharged into an external heat exchanger or other heat dissipation system. Therefore, the four cooling features 442 are fluidly connected in series.

[0107] exist Figure 4B, it can be seen that there are two main coolant flow path segments extending from the first rotational joint 412a through the second rotational joint 412b and the third rotational joint 412c, and are fluidly connected to the cooling feature 442d, so that the coolant can be circulated through the cooling feature 442d. Other coolant flow path segments are shown as branching from these two main coolant flow path segments and leading to the cooling feature 442c and the cooling features 442a, 442b. Therefore, the coolant is supplied to the cooling features 442a, 442c and 442d in parallel. However, the cooling features 442a and 442b are fluidly connected in series. Therefore, the coolant flow path segments can be arranged to be fluidly connected to the cooling features in parallel and / or in series.

[0108] exist Figure 4C , it can be seen that a completely independent coolant flow path segment is provided for each cooling feature 442a to 442d. This arrangement allows coolant to be delivered to different cooling features 442 at different rates (which can be changed as needed through the use of flow metering devices or valves), but the greater amount of hardware required to route eight independent flow paths through the first rotary joint 412a may require more space than the two flow path implementation of the other examples.

[0109] As previously mentioned, a wafer handling robot such as the one described above may be used in a VTM. Figure 5 A diagram of a VTM 502 is shown having a plurality of process chambers 504 connected thereto, for example, by slit valves or other closable apertures (not shown). A wafer handling robot having a robot arm assembly 510 and a robot arm base 508 may be mounted to the VTM 502 such that the robot arm base 508 is mounted external to the VTM 502 and the robot arm assembly 510 is located internal to the VTM 502, for example in a vacuum environment. The robot arm assembly 510 may, for example, include the ferrofluid seals and cooling features described above.

[0110] It should be understood that although the present disclosure focuses on wafer handling robots as examples of robots, and these wafer handling robots can incorporate ferrofluid seals or other vacuum compatible rotary sealing technologies to allow the interior of the robot arm to be maintained at atmospheric (or at least higher) pressure, thereby facilitating the use of flexible cooling circuits within the robot arm to allow fluid cooling of components inside the robot arm, the principles and concepts discussed herein can also be applied to robot arms used for other purposes under vacuum conditions. The present disclosure should be understood to include these alternative implementations.

[0111] Control of, for example, a wafer handling robot as described above may be facilitated by the use of a controller, which may be part of a semiconductor processing tool having the wafer handling robot, or may be integrated into the wafer handling robot itself. The above systems may be integrated with electronics to control their operation before, during, and after processing semiconductor wafers or substrates. The electronics may be referred to as a "controller," which may control various components or subcomponents of one or more systems. Depending on the processing requirements and / or system type, the controller may be programmed to control the operation of any of the systems disclosed herein, including various motors and / or sensors, etc., which may be introduced into the wafer handling robot.

[0112] Broadly speaking, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions may be instructions sent to the controller in the form of various individual settings (or program files) that define the operating parameters used to perform specific wafer transfer operations within a VTM using the wafer handling robot disclosed herein.

[0113] In some implementations, the controller may be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the "cloud" or all or part of a wafer fab host system that may allow remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, check the history of past manufacturing operations, check trends or performance criteria for multiple manufacturing operations, change parameters of a current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide a process recipe to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller may be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose (e.g., the processes and controls described herein). An example of a distributed controller for such a purpose is one or more integrated circuits within a chamber (e.g., a VTM) communicating with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control wafer transfer operations using a wafer handling robot in the VTM.

[0114] An example VTM having a wafer handling robot as described herein may be connected, but is not limited to, to one or more other parts of the equipment, including a plasma etching chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a chamfer edge etching chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etching (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, or any other semiconductor processing system that may be associated with or used for the manufacture and / or preparation of semiconductor wafers.

[0115] As described above, depending on one or more processing steps to be performed by the tool, the controller can communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a host computer, another controller, or tools (e.g., FOUPs) used in material transport for transporting wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

[0116] For purposes of this disclosure, the term "fluidically connected" is used to refer to volumes, plenums, holes, etc., which can be connected to each other directly or through one or more intermediate components or volumes to form a fluid connection, similar to the term "electrically connected" used to refer to components that are connected together to form an electrical connection. The term "fluid interposition" (if used) can be used to refer to a component, volume, plenum, or hole that is fluidly connected to at least two other components, volumes, plenums, or holes, so that fluid flowing from one of those other components, volumes, plenums, or holes to the other or another of those components, volumes, plenums, or holes will first flow through the "fluid interposition" component and then reach the other or another of those components, volumes, plenums, or holes. For example, if a pump is fluidly interposed between a reservoir and an outlet, fluid flowing from the reservoir to the outlet will first flow through the pump and then reach the outlet. The term "fluidically adjacent", if used, refers to the placement of one fluid element relative to another fluid element such that no possible structure is fluidly interposed between the two elements that could interrupt fluid flow between the two fluid elements. For example, in a flow path having a first valve, a second valve, and a third valve sequentially positioned there along, the first valve is fluidly adjacent to the second valve, the second valve is fluidly adjacent to both the first and third valves, and the third valve is fluidly adjacent to the second valve.

[0117] Any ordinal labels (if any) used in the present disclosure and claims, such as (a), (b), (c) ... or (1), (2), (3) ... or the like, should be understood as not conveying any particular order or sequence unless such order or sequence is explicitly indicated. For example, if there are three steps labeled (i), (ii), and (iii), it should be understood that the steps can be performed in any order (or even simultaneously, if there are no other limitations) unless otherwise indicated. For example, if step (ii) involves the operation of an element produced in step (i), then step (ii) can be considered to occur at a point after step (i). Similarly, if step (i) involves the operation of an element produced in step (ii), it should be understood to be the opposite. It should also be understood that the use of the ordinal label "first" (e.g., "first item") in this document should not be interpreted as implicitly or inherently suggesting that there must be a "second" instance (e.g., "second item").

[0118] It should be understood that the phrases "for each <item> in one or more <items>," "each <item> in one or more <items>," and the like, if used herein, include both single-item groups and multi-item groups, i.e., the phrase "for...each" is used in the sense that it is used in a programming language to refer to each item in any group of items referenced. For example, if the group of items referenced is a single item, then "each" will refer only to that single item (although dictionary definitions of "each" often define the term to mean "each of two or more things"), and does not mean that there must be at least two of those items. Similarly, the terms "set" or "subset" by themselves should not be taken to necessarily cover multiple items - it should be understood that a set or subset may cover only one member or multiple members (unless the context dictates otherwise).

[0119] Unless otherwise indicated, when the term "between" used in this article is used with a numerical range, it should be understood to include the starting and ending values ​​of the range. For example, between 1 and 5 should be understood to include numbers 1, 2, 3, 4 and 5, not just numbers 2, 3 and 4.

[0120] The term "operably connected" should be understood to refer to a state in which two components and / or systems are directly or indirectly connected so that, for example, at least one component or system can control the other. For example, a controller may be described as being operably connected to a resistive heating unit, including a controller connected to a sub-controller of the resistive heating unit, the sub-controller being electrically connected to a relay, the relay being configured to controllably connect or disconnect the resistive heating unit from a power source capable of providing an amount of electricity that can be supplied to the resistive heating unit to produce a desired degree of heating. Because of the electrical current involved, the controller itself may not be able to directly provide such power to the resistive heating unit, but it should be understood that the controller is still operably connected to the resistive heating unit.

[0121] It should be understood that the examples and implementations described herein are for illustrative purposes only, and that those skilled in the art will associate various modifications or variations therewith. Although various details have been omitted for clarity, various design alternatives may be implemented. Therefore, the present examples are considered to be illustrative rather than restrictive, and the present disclosure is not limited to the details set forth herein, but may be modified within the scope of the present disclosure.

[0122] It should be understood that although the above disclosure focuses on one or more specific exemplary implementations, it is not limited to the examples discussed, but is also applicable to similar variations and mechanisms, and such similar variations and mechanisms are also considered to fall within the scope of the present disclosure.

Claims

1. A device comprising: Robot arm base; a robotic arm assembly comprising one or more arm links and a first set of one or more revolute joints, each revolute joint of the first set of one or more revolute joints comprising a respective vacuum compatible seal; a plurality of components defining a plurality of coolant flow path segments; and a first set of one or more cooling features, each cooling feature of the first set of one or more cooling features being fluidly connected to and having fluid interposed therebetween at least two of the coolant flow path segments, wherein: A base revolute joint of the one or more revolute joints revolves to rotatably connect a first arm link of the one or more arm links to the robot arm base, and At least two of the coolant flow path segments extend from the robot arm base, through the base rotation joint and into at least the first arm link.

2. The device according to claim 1, wherein: The one or more vacuum compatible seals include at least a first vacuum compatible seal, and The one or more cooling features include one or more vacuum-compatible seal cooling features, and the one or more vacuum-compatible seal cooling features include a first vacuum-compatible seal cooling feature, which is configured to cool the first vacuum-compatible seal when coolant flows into the first vacuum-compatible seal cooling feature through at least one of the coolant flow path segments and flows out of the first vacuum-compatible seal cooling feature through at least one other of the coolant flow path segments.

3. The device according to claim 2, wherein: the first vacuum compatible seal cooling feature comprising a passage extending through at least a portion of a tubular region, the tubular region having a centerline coaxial with an axis of rotation of one of the one or more revolute joints including the first vacuum compatible seal, and The tubular region surrounds one or more surfaces of the first vacuum compatible seal, the one or more surfaces facing radially inwardly toward the axis of rotation of the one of the one or more revolute joints that includes the first vacuum compatible seal.

4. The device according to claim 3, wherein: The channel is at least partially defined by one or more surfaces of the first vacuum compatible seal, the one or more surfaces facing radially outwardly away from the axis of rotation of the one of the one or more revolute joints that includes the first vacuum compatible seal.

5. The device according to claim 2, wherein: the first vacuum compatible seal cooling feature comprising a passage extending through at least a portion of a tubular region, the tubular region having a centerline coaxial with an axis of rotation of one of the one or more revolute joints including the first vacuum compatible seal, and The tubular region is surrounded by one or more surfaces of the first vacuum compatible seal, the one or more surfaces facing radially inwardly toward the axis of rotation of the one of the one or more revolute joints that includes the first vacuum compatible seal.

6. The device according to claim 5, wherein: The channel is at least partially defined by the one or more surfaces of the first vacuum compatible seal, the one or more surfaces facing radially inwardly toward the axis of rotation of the one of the one or more revolute joints that includes the first vacuum compatible seal.

7. The device according to any one of claims 3 to 6, wherein the channel has an annular shape or a ring segment shape.

8. The device according to any one of claims 1 to 7, wherein: The robot arm assembly includes a first motor, and The one or more cooling features include one or more motor cooling features, and the one or more motor cooling features include a first motor cooling feature, which is arranged adjacent to or around a portion of the first motor and is configured to cool the first motor when coolant flows into the first motor cooling feature through at least one of the coolant flow path segments and flows out of the first motor cooling feature through at least one other of the coolant flow path segments.

9. An apparatus according to any one of claims 1 to 8, wherein the one or more cooling features include one or more arm-link cooling features, the one or more arm-link cooling features include a first arm-link cooling feature, the first arm-link cooling feature is arranged adjacent to or located in the material forming one of the one or more arm links, and the first arm-link cooling feature is configured to cool the arm link when coolant flows into the first arm-link cooling feature through at least one of the coolant flow path segments and flows out of the first arm-link cooling feature through at least one other of the coolant flow path segments.

10. The apparatus of claim 9, wherein the first arm link cooling feature extends along at least half of the length of the arm link, the first arm link cooling feature being disposed adjacent to or in the material of the arm link.

11. The apparatus of any one of claims 1 to 10, further comprising a first sensor located within one of the one or more arm links, the one or more cooling features comprising one or more sensor cooling features, the one or more sensor cooling features comprising a first sensor cooling feature, the first sensor cooling feature being disposed adjacent to or surrounding a portion of the first sensor and configured to cool the first sensor when coolant flows into the first sensor cooling feature via at least one of the coolant flow path segments and flows out of the first sensor cooling feature via at least one other of the coolant flow path segments. The device of claim 11 , wherein the first sensor is an optical sensor.

13. The apparatus of claim 12, wherein the first sensor is an imaging sensor.

14. The device according to any one of claims 11 to 13, wherein: The one or more arm links include a first end effector arm link having a first end effector, and The first sensor is located in the first end effector arm link.

15. The apparatus of claim 14, wherein the first sensor is positioned to collect data from a location below the first end effector arm link.

16. The apparatus of claim 14, wherein the first sensor is positioned to collect data from a location above the first end effector arm link.

17. The apparatus of any one of claims 14 to 16, wherein the first end effector arm link is also the first arm link.

18. The device according to any one of claims 14 to 16, further comprising a second sensor, wherein: The one or more arm links also include a second end effector arm link having a second end effector, The second sensor is located in the second end effector arm link, The one or more arm links also include a forearm link, The first end effector arm link is rotatably connected to the forearm link via a first rotational joint of the one or more rotational joints, The second end effector arm link is rotatably connected to the forearm link via a second swivel joint of the one or more swivel joints, and The one or more sensor cooling features include a second sensor cooling feature disposed adjacent to or surrounding a portion of the second sensor and configured to cool the second sensor when coolant flows into the second sensor cooling feature via at least one of the coolant flow path segments and flows out of the second sensor cooling feature via at least one other of the coolant flow path segments.

19. The apparatus of claim 18, wherein: The first rotational joint is configured to enable the first end effector arm link to rotate relative to the forearm link about a first rotational axis, The second rotational joint is configured such that the second end effector arm link can also rotate relative to the forearm link about the first rotational axis, The first end effector is disposed at a higher height than the second end effector, The first end effector arm link includes a first body portion and a first shaft portion, the first shaft portion extending through the second end effector link, The first shaft portion is supported by the first rotational joint, The first revolute joint includes a first vacuum compatible seal that seals between the second end effector link and the first portion of the first end effector link, The second sensor and the second sensor cooling feature are both located at a location within the second arm link that is radially outward of the first vacuum compatible seal relative to the first rotational axis, and The first vacuum compatible seal is interposed between the first body portion and a location on the first shaft portion where a coolant flow path segment leading to the second sensor cooling feature exits the first portion.

20. The apparatus of claim 19, wherein: an opening extending through the first shaft portion across an arc about the first axis of rotation, and The coolant flow path segment leading to the second sensor cooling feature exits the first shaft portion via the opening.

21. The device of claim 20, wherein the arc segment extends through at least 90 degrees.

22. The device of any one of claims 1 to 16, wherein the one or more arm links comprises a plurality of arm links.

23. The apparatus of claim 22, wherein: The second rotation joint can rotationally connect two arm links among the plurality of arm links; At least two of the coolant flow path segments pass through the base rotation joint, and At least two of the coolant flow path segments pass through the second rotational joint.

24. An apparatus according to any one of claims 1 to 23, wherein at least some of the coolant flow path segments are at least partially provided by flexible polymer tubing.

25. The apparatus of any one of claims 1 to 24, wherein the components defining each flow path segment include components selected from one or more of: lengths of flexible polymer tubing, lengths of rigid tubing, flow-dividing devices, straight-through connectors, and fittings.

26. The apparatus of any one of claims 1 to 25, further comprising a purge gas exhaust feature, wherein: The purge gas exhaust feature includes one or more purge gas outlets fluidly connected to one or more purge gas plenums and configured to direct purge gas radially outward from the one or more purge gas plenums to a vicinity of a respective one of the one or more rotary joints, and One or more purge gas lines are arranged to be routed from the robot arm base, through the base rotation joint and into at least the first arm link.

27. The device of any one of claims 1 to 26, wherein at least one of the one or more rotational joints comprises a respective vacuum compatible seal, the vacuum compatible seal being a ferrofluid seal.

28. The apparatus of any one of claims 1 to 27, wherein each rotary joint comprises a respective vacuum compatible seal, the vacuum compatible seal being a ferrofluid seal.

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