Non-contact conveying device

Abstract

A transport device is disclosed which is designed to transport one or more payloads, in particular wafers, by means of a carrier. The carrier floats on a transport surface of a stator and is movable and positionable. Preferably, the movement and positioning takes place in all six degrees of freedom. The carrier has a movable boom or a movable manipulator or a movable robot arm. A payload can be placed or fixed on its end effector. In a development, the payload can also be processed and / or inspected. This processing and / or inspection can also be performed by an end effector of another carrier of the same transport device.

Description

Technical Field

[0001] The present invention relates to a non-contact conveying device described in the generic concept of claim 1. In particular, the conveying device according to the present invention is suitable for industrial applications in assembly technology, the biological industry, the chemical industry, the pharmaceutical industry and the food industry, as well as for industrial applications in solar cell manufacturing / display manufacturing, medical technology, laboratory automation and logistics. Particularly preferably, the conveying device is used in the semiconductor industry.

Background Art

[0002] In the scope of technical manufacturing, often, payloads such as materials, workpieces, tools or products have to be conveyed or positioned. For this purpose, both contact-type conveying devices and non-contact-type conveying devices, which are used, for example, in mechanical construction and system construction, are known, and these are used, for example, for the conveyance of payloads in packaging machines, the positioning of mechanical elements or the most precise possible orientation of tools with respect to workpieces, for laser processing, for example, or in the semiconductor industry for the coating, exposure or structuring of substrates in wafer cluster systems or stepper systems. In this case, a magnetic levitation system can be used.

[0003] The problem in magnetic levitation is to create a structure that stably levitates in a magnetic field. Another problem is to automatically position and / or move the levitating structure in all six degrees of freedom (three degrees of freedom each in translation and rotation) corresponding to the target setting, which is also referred to as complete magnetic levitation.

[0004] According to German Patent Application Publication No. 102016224951, the controlled conveyance and positioning of a carrier supporting a payload relative to a stator in a predetermined manner is made possible by the following. That is, one of the two elements has a plurality of position magnets arranged at least partially movably, and the position and / or orientation of each of these position magnets can be controlled and set relative to this element via a position element. The other of the two elements has at least two stationary magnets fixedly coupled to this element, and this is made possible by these stationary magnets being magnetically coupled to the position magnets. The conveying device is configured to convey the carrier relative to the stator by the controlled positioning and / or orientation of the plurality of position magnets. Here, the carrier is also moved and held in a desired position and / or orientation relative to the stator.

[0005] German Patent Application Publication No. 102016224951 provides the advantage that the lifting and / or forward movement of the carrier relative to the stator can be enabled by the corresponding positioning and / or orientation of the positioning magnets by each position element. This can omit the provision of a complex arrangement and drive control of the solenoid. Thereby, not only the complexity of the conveying device and thus the manufacturing cost are reduced, but also the use of permanent magnets that can provide a magnetic flux density significantly greater than that of solenoids often used for such purposes becomes possible. Similarly, this enables a greater lifting height or a greater gap between the stator and the carrier, thereby providing a greater margin of movement during movement in the Z direction and / or the tilt angle range and the rotation angle range. Furthermore, this provides the advantage that an interruption in the supply of electrical energy does not necessarily cause a functional error, let alone a cause of damage. In particular, an interruption in the power supply does not cause a loss of the magnetic field or magnetic connection between the stator and the carrier. For example, during an interruption in the power supply, as long as the position and / or orientation of the positioning magnets follow the action of the attracting force of the stationary magnets, the connecting force between the positioning magnets and the stationary magnets may be increased, followed by the carrier being pulled towards the stator and protected against uncontrolled falling. The magnetic connection between the stator and the carrier causes the lifting of the carrier, i.e., the lift above the stator, and further causes the forward movement of the carrier relative to the stator, i.e., the conveyance, without necessarily requiring another contact or non-contact system for this purpose.

[0006] Therefore, since non-contact conveyance is possible, the disclosed conveyance device can be used even in an environment with high cleanliness requirements. For example, the conveyance body can be conveyed in an environment with high cleanliness requirements, while on the other hand, the stator is arranged in an outer environment with relatively low cleanliness requirements. To separate the various clean areas, a separating element may extend through the gap between the stator and the conveyance body. Therefore, the disclosed conveyance device is also suitable for use in biological, chemical, and / or pharmaceutical processes, as well as in, for example, airtight areas, liquidtight areas, and / or encapsulated areas.

[0007] In a typical semiconductor manufacturing line, wafers are processed in a manufacturing system (e.g., a cluster tool). Usually, wafers are conveyed between multiple manufacturing systems in a conveyance container under standard pressure, and this conveyance is performed as a lot having a typical lot size of 25. Inside the manufacturing system, wafers are usually processed and conveyed under ultra-high vacuum (UHV). The manufacturing system includes at least one process station for processing wafers, a conveyance device for conveying wafers in a vacuum as described at the beginning, and a storage area for storing unprocessed and processed wafers. At least one process station, the conveyance device, and the storage area are enclosed in a vacuum-sealed chamber and can be evacuated to UHV. These chambers are arranged adjacent to each other laterally and are connected to each other, in some cases, via a vacuum-sealed door.

[0008] To transfer wafers between the conveyance container and the manufacturing system and store multiple wafers in the vacuum area, the manufacturing system is provided with a so-called vacuum load lock. The conveyance container is inserted into the vacuum load lock under standard pressure, and then the vacuum load lock is evacuated. Next, the vacuum door between the vacuum load lock and the conveyance area of the manufacturing system is opened, and the wafers are taken out of the conveyance device through this door and outside the conveyance container, or inserted into the conveyance container.

[0009] After all wafers are removed from the carrier, processed, and placed back into the carrier, the vacuum gate is closed and air is introduced into the vacuum load lock. Subsequently, the carrier is removed from the vacuum load lock under standard pressure and transported, for example, to the next manufacturing system.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0011] The problem of the present invention is to provide a transport device that enables a complex and efficient movement flow. The functional range of the transporter should be extensible to functions such as operating, positioning, fixing, for example, clamping, processing, and / or inspecting the payload located on or around the transporter. In technical manufacturing or logistics, new functions and flows with a high level of automation, high efficiency, and high economy should be realized.

Means for Solving the Problems

[0012] The above problems are solved by a transport device having the features of claim 1. Other advantageous configurations of the present invention are described in the dependent claims.

[0013] The conveying device according to the present invention is designed to move at least one conveyor (mover) equipped with a manipulator in a non-contact manner. The manipulator is coupled to the conveyor, or more precisely to the housing of the conveyor, either as an interchangeable module or as a fixed component of the conveyor, and moves with the conveyor. The conveyor equipped with the coupled manipulator can be positioned in its six degrees of freedom of movement with respect to the stator by the magnetic field of the stator. Furthermore, the manipulator has at least one additional degree of freedom of movement that can be positioned with respect to the housing of the conveyor during the levitation operation of the conveyor.

[0014] By synchronously controlling the movement of the degrees of freedom of the housing and the manipulator, a complex and efficient movement flow becomes possible. The manipulator extends the functional range of the conveyor to functions such as operating, positioning, fixing, for example clamping, processing and / or inspecting an effective load located on or around the conveyor. The conveyor equipped with the manipulator opens up a number of new fields of use for the conveying device according to the present invention. This enables new functions and flows with a high level of automation, high efficiency and high economy in technical manufacturing or logistics.

[0015] Corresponding to the present invention, the manipulator that is moved together on the conveyor serves as a substitute for a stationary manipulator that must be provided at the loading and target locations when the conveyor does not have its own operating function. The greater the number of positions to be approached, the greater the reduction in stationary components, and thus the lower the complexity and cost of the entire system.

[0016] In typical use, the manipulator has an end effector that loads the payload onto the carrier at the loading location and unloads it at the target location. The manipulator may also have a clamping function that securely holds the payload on the carrier during transportation. Further, the manipulator may be provided to re-orient the payload during transportation so that it is delivered in the correct orientation at the target location without additional time cost.

[0017] In other uses, the manipulator is a motion mechanism that guides an end effector, such as a process tool or inspection means. The carrier thus equipped can process the payload that is moved together or the payload in its vicinity by this tool, or can be inspected by the inspection means. In this case, it has high motion flexibility. Further time or economic advantages are obtained from the parallelization of multiple flows when performing the transport task and the manipulation task simultaneously. Further, the manipulator may be equipped to perform multiple functions (for example, operation and inspection). Further, multiple manipulators may be provided on one carrier.

[0018] Finally, multiple carriers that perform one task together may be provided. For example, the workpiece is fixed on a first carrier without a manipulator and transported. A second carrier with a manipulator follows the first carrier, and an operation task, a processing task, or an inspection task is performed on the transported workpiece by this manipulator.

[0019] The above-mentioned re-orientation of the payload can also be realized by multiple carriers of the transport device according to the present invention.

[0020] A particular advantage occurs when using the conveying device according to the invention in the semiconductor industry, in the case where the workpiece is, for example, a wafer. Advantageously, the carrier is used for the conveyance of semiconductor wafers in the vacuum conveyance space of a manufacturing system. The stator is arranged below the vacuum conveyance space. A typical conveyance task in such a manufacturing system (cluster tool) is to remove a wafer from the process nest of one process station and convey it to the process nest of another process station. The process stations are arranged in the vicinity of the side of the conveyance space in the manufacturing system, and thus, since the carrier cannot be directly reached, the manipulator according to the invention bridges the conveyance section from the process nest to the conveyance space. The manipulator according to the invention enables the reception and placement of wafers spatially offset with respect to the conveyance space or the conveying device, and in this case, the center of gravity of the wafer can be positioned at a distance from the carrier.

[0021] The manipulator has at least one degree of freedom, which conveys an end effector, which may be loaded with an effective load (wafer) in some cases, on the movement trajectory (for example, from the process nest) to the carrier. At this time, the movement mechanism contracts to form a compact unit together with the carrier and the effective load (wafer). This compact unit occupies approximately one-half to one-fourth of the conveyance surface compared to an equivalent carrier equipped with a rigid end effector. The manipulator is extended in front of the process nest, for example, for loading and unloading. During conveyance, the manipulator is in a contracted state so that the carrier can be better maneuvered. The reduced conveyance surface can be utilized to increase the number of carriers on the stator (in the conveyance space), and thus, to increase the throughput and economy of the conveying device (of the manufacturing system). The manipulator can be variably positioned. When the positions of the carriers on the conveyance surface are equal, the carrier can move the effective load (wafer) to any intermediate position between its terminal positions. Thus, in the case of a manufacturing system for wafers, the process nests can be loaded at various intervals with respect to the conveyance surface of the stator.

[0022] In addition to the contraction movement, the manipulator may have additional degrees of freedom. For example, a manipulator having two degrees of freedom may be provided. In this case, the first degree of freedom performs the above-described contraction movement in a plane parallel to the transport surface, and the second degree of freedom performs a lift movement perpendicular to the transport surface. Although the lift movement may already be positioned as a degree of freedom of the transporter, the adjustment range is narrowly limited by the levitation method. The manipulator can be designed to match a relatively large lift area. A transporter equipped with such a manipulator can load wafers into process nests arranged at various heights. It is also possible to load the wafer cassette in the load lock. In this case, it is possible to perform the desired loading of one of the plurality of compartments of the wafer cassette, which are vertically arranged one above the other in the vertical direction.

[0023] Different from a transporter not equipped with a manipulator, the following advantages can be obtained or can be achieved by a preferred configuration. a) Extended working area: The manipulator can have a movement mechanism that extends beyond the boundaries of the transporter within the range of its degrees of freedom and reaches locations outside the working area of a transporter not equipped with a manipulator. For example, it can reach locations near the side of the transport surface or locations at various heights on the transport surface. b) Reduced complexity of the entire system: The manipulator can receive the effective load at various supply locations, transport it onto the transporter, and lower it again at the target location. In this case, another stationary operating device is not required. Therefore, the mobile manipulator can, in some cases, substitute for a plurality of stationary manipulators. This reduces the complexity and cost of the entire system. c) Reduced transport surface: To keep the outer dimensions of the transporter equipped with the manipulator and the effective payload small, the manipulator can transport the effective payload, in particular via its housing, towards the center of the transporter. Thus, during transport, the transport surface covered by the transporter is, for example, reduced by a factor of two to four compared to a transporter equipped with a rigid end effector. This has a number of advantageous effects described in d) to f). d) Higher throughput: By the approach described in c), more transporters can be accommodated on a predefined transport surface, thereby increasing the throughput. e) Smaller system size: For a predefined number of transporters, by the approach described in c), the transport surface can be reduced, thereby providing significant cost advantages, for example, in a vacuum transport space with high operating costs in semiconductor manufacturing. f) Better maneuverability: By the approach described in c), the transporter can have small outer dimensions, in which case the transporter becomes more easily maneuverable. Compensatory movements are not required, the movement trajectory is shortened, the maneuvering is accelerated, and the reversing maneuver can be carried out at this location without interfering with other transporters even in a transport space with small dimensions. g) Time and efficiency gain: The operation task, processing task or inspection task in the effective payload can be executed while the effective payload is being transported. By parallelizing multiple flows in this way, the processing cycle time is shortened. h) Purely mechanical structure: The device consisting of the carrier and the manipulator may be constructed purely mechanically without electrical or electronic components. The stator is responsible for precise positioning and provides mechanical energy for the forward movement of the carrier and the drive of the manipulator. The energy is transmitted from the stator to the carrier or the manipulator of the carrier by a magnetic field. As a result, the structure becomes extremely space-saving, lightweight, and inexpensive. Since there is no need for an energy accumulator, there is no need to assume the time and area for electrically charging the energy accumulator. In the absence of an electronic device, there is no heat loss and no need for cooling. This is particularly advantageous in a vacuum where heat dissipation from the levitation device is only possible to a limited extent by radiation. It becomes possible to design a purely mechanical structure for significantly higher operating temperatures because the normal temperature limits for protecting electronic devices and energy accumulators are eliminated. A purely mechanical device may be optimized for use under special conditions, particularly for use in a vacuum (when using materials that can be immersed in a vacuum), for use in areas where there is a risk of explosion (since there is no risk of electrical spark formation), for use in a gas atmosphere or in a liquid, and also for use under extremely high ambient pressures. i) Flexibility due to modularity: The mechanical interface between the carrier and the manipulator may have a quick-clamping device and a coupling, whereby various types of manipulators can be exchanged and used in various types of carriers. To equip the carrier for new applications, the exchange of the manipulator can be carried out quickly and easily, manually or automatically.

[0024] Preferably, the carrier and the assigned payload are received in a sealed transport space. The stator is arranged below the sealed transport space. Preferably, each housing of the carrier is also sealed. Thus, a transport device for payloads, in particular wafers, which can be processed in special environments rather than under normal conditions at various process stations is realized. The transport of the payload by the carrier of the transport device according to the invention is likewise carried out in a special environment rather than under normal conditions.

[0025] Preferably, a gas (e.g., a protective gas, nitrogen or an inert gas) or a gas mixture (e.g., clean air) or a vacuum or an ultra-high vacuum (e.g., up to 10 -7 bar or up to 10 -8 bar) or a sterile area or an ABC protection area or a liquid (e.g., up to 2 bar) is provided in the sealed transport space.

[0026] Various embodiments of the transport device according to the invention, with various embodiments of the carrier, are illustrated.

Brief Description of the Drawings

[0027]

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DETAILED DESCRIPTION OF THE INVENTION

[0028] Three variants of the transfer device according to the present invention are schematically shown in FIGS. 1a to 1c. Each of these includes one stator 3 and at least one carrier 2 that is controlled to be conveyed in a non-contact manner relative to the stator 3. For this purpose, the stator 3 has a position magnet 31 (see FIG. 7) arranged movably in a planar arrangement, and the orientation of the position magnet can be changed by an actuator. By the superposition of the magnetic fields of all the position magnets 31, a magnetic field, herein referred to as a levitation field, is generated. This projects upward through the cover plate of the stator 3. The cover plate simultaneously forms a transfer surface 33, through which the carrier 2 provided with a magnet array is conveyed in a non-contact manner.

[0029] The sensor system periodically detects, with high frequency and accuracy, the position of each carrier 2, more precisely the position of the housing 21 of the carrier 2, in its six degrees of freedom of movement over the transfer surface 33. As in the case of each rigid body, these are three degrees of freedom X, Y, Z in the translation of the housing 21 and three degrees of freedom rX, rY, rZ in the rotation. From this, the control device calculates the position deviation with respect to a predetermined target position or target trajectory and controls the magnet angle so that the control deviation is minimized. In this way, the housing 21 of the carrier 2 is stably and robustly guided against external forces with respect to the target trajectory.

[0030] In the embodiments of FIGS. 1a and 1b, the carrier 2 has a drive unit 23 for the housing 21, and this drive unit 23 includes at least one magnet array 231 (see FIG. 2) fixed to the housing. During operation, the magnet array 231 receives forces and moments in the levitation field, which are transmitted to the rigidly connected housing 21, causing this housing 21 to move. In this way, the magnet array 231 acts as a drive unit 23 for the housing 21.

[0031] So that this drive can be carried out under control, the drive unit 23 belongs to means for detecting the position of the housing 21. The position detection is carried out with respect to the stator 3 by attaching a position sensor to one of the two components and attaching a code array 233 detected by the position sensor to the other component. For example, a method for position detection based on a camera can be used by a camera module 32 attached to the housing 21 detecting the code array 233 on the stator 3. In FIGS. 1a and 1b, a camera module 32 (see FIG. 7) incorporated in the stator 3 detects the code array 233 in the housing 21.

[0032] According to the present invention, the carrier 2 is accompanied by a movable and controllable manipulator 22 for the payload (not shown in FIG. 1), and the manipulator 22 is attached to the housing 21. The manipulator 22 includes a motion mechanism 221 with an end effector 222, and the end effector 222 is configured as a placement site, gripper, clamping device, tool or inspection means according to the task.

[0033] Preferably, the end effector 222 is attached to the motion mechanism 221 as a quickly replaceable component, and / or the motion mechanism 221 is attached to the housing 21 as a quickly replaceable component. Thus, by manually or automatically replacing the manipulator 22 or the end effector 222, the carrier 2 can be quickly equipped for a new task. This includes structural members and joints, which give the end effector 222 at least one degree of freedom of movement with respect to the housing 21. The joints are, for example, pivot bearings, linear guides, guides with flexure joints, or combinations thereof.

[0034] To move the motion mechanism 221 under control or adjustment in at least one of its degrees of freedom, the manipulator 22 is coupled to the drive unit 24 via a coupling 26. The drive unit 24 transmits kinetic energy to the motion mechanism 221 and enables controlled positioning. For controlling a motion mechanism 221 having a plurality of degrees of freedom, it may be provided with one drive unit 24 having a plurality of degrees of freedom, or a plurality of drive units for operating all degrees of freedom of the motion mechanism 221 in total may be provided.

[0035] Figure 1b shows a purely mechanically constructed carrier 2 with a mechanical drive unit 24 for the manipulator 22. This includes a magnet array 241 coupled to the housing 21 of the carrier 2 via a bearing 244. By the bearing 244, the magnet array 241 can move in at least one degree of freedom with respect to the housing 21. Since the magnet arrays 231, 241 are arranged laterally spaced apart on the lower surface of the carrier 2, both are located in the action area of the levitation field, and the forces and moments acting between them are small compared to the forces and moments they receive in the levitation field.

[0036] The levitation field of the stator 3 applies a vector force and a vector moment to the movable magnet array 241. The force vector and the moment vector are divided into two vector components along the guiding direction of the bearing 244. One of these acts in the guiding direction of the bearing 244, and the other is orthogonal to the guiding direction. The component in the guiding direction is transmitted from the movable magnet array 241 to the motion mechanism 221 via the driven part 245, such as a shaft or a push rod, and the coupling 26, and can move the motion mechanism 221. A transmission device may also be provided to adapt the rotational speed of the driven part to the rotational speed of the motion mechanism 221. The component transverse to the guiding direction is transmitted from the magnet array 241 to the housing 21 via the bearing 244 and affects the motion of the housing 21 together with another magnet array.

[0037] The position of the magnet array 241 with respect to the housing 21 can be detected by the cord array 243 on the movable magnet array 241. In this way, the position of the magnet array 241 can be controlled. When the magnet array 241 is firmly connected to the end effector 222 via the coupling 26 and the motion mechanism 221, the position of the magnet array 241 can be converted to the position of the end effector 222 by the mathematical model of the manipulator 22, and vice versa. By using this conversion, the position of the end effector 222 can also be set as a control target value.

[0038] Special environmental conditions, such as · cleaning of the carrier 2 (separation of wet outside / dry inside), · use under vacuum (separation of vacuum outside / gas filling inside), · food area or pharmaceutical area (separation of sterility outside / non-sterility inside), · explosion-proof area In the case of use under [conditions], the sealed housing 21 for the carrier 2 is significant. In this case, the coupling 26 between the driven part of the carrier 2 and the manipulator 22 may be configured as a magnetic coupling involving non-contact torque transmission. For example, the housing 21 of the carrier 2 is sealed when used under vacuum, whereby the atmosphere inside the carrier 2 can be separated from the surrounding vacuum. Since mechanical rotation execution within the housing wall can break the seal, the magnetic coupling can be advantageously used.

[0039] In other developments, the drive unit 24 may form a single component group together with the manipulator 22. For example, the magnet array 241 and the cord array 243 may be incorporated into the joints of the motion mechanism 221, in which case the bearings 244 and the coupling 26 are omitted. When the magnet array 241 is located in the action area of the levitation field, forces and moments can be applied to the magnet array 241 via the stator 3, and then these forces and moments are directly transmitted to the motion mechanism 221. When the manipulator 22 is replaced, the drive unit 24 is necessarily replaced as well.

[0040] The manipulator 22 shown in Figure 1a can be selectively driven electrically by an electric motor or mechanically by the drive unit 24. In the former case (electrical drive), electrical energy is supplied to the electric motor via the electronic unit 25, and data regarding the target position is supplied. In the latter case (mechanical drive), the electronic unit 25 may be provided within the housing 21, for example, to supply current to a position sensor housed within the housing 21.

[0041] The electronic unit 25 optionally includes the following electrical or electronic components provided within the carrier 2, namely, an energy accumulator 251 for providing electrical energy, such as a battery or a capacitor, and a load, for example, · a wireless communication interface 252 for communicating with the base unit within the stator 3, · A sensor system for detecting the degrees of freedom of the carrier 2 and the manipulator 22, · An electrical drive unit 24 for the manipulator 22, · A user interface 253 that provides the user with energy supply and data supply for additional application-specific units on the carrier 2 is included.

[0042] In a preferred variant according to Figure 1b, the carrier 2, together with the manipulator 22, is constructed purely mechanically or passively. The electronic unit 25 is omitted. This has the advantages, namely, · Reduction of the structural size, weight and complexity of the carrier 2, · Reduction of the time and area required to charge the energy accumulator 251, · Enabling or facilitating use under extreme environmental conditions (for example, high temperature, vacuum, high pressure, humidity) has.

[0043] Figure 1c shows one variant of the purely mechanical structure of the carrier 2 in which a combined drive unit 24 for the housing 21 and the manipulator 22 is used. Different from the embodiments of Figures 1a and 1b, none of the magnet arrays 241 are fixedly coupled to the housing 21 and each has its own bearing 244 and its own degree of freedom of movement.

[0044] The bearings 244 are designed and arranged such that controlled movement of the housing 21 is always possible in all six degrees of freedom with respect to the housing 21. If a magnet array 241 cannot drive and control the degrees of freedom of the housing 21, at least one other magnet array 241 for operating this degree of freedom is provided. By means of a suitable structure of the housing 21 and the bearings 244, a special setting of the magnet arrays 241 in which the housing 21 is controllable only in less than five degrees of freedom is excluded.

[0045] FIG. 2 shows an exemplary ring-shaped magnet array with permanent magnets that can be used as a magnet array 231 fixed to the housing and as a magnet array 241 movable relative to the housing 21.

[0046] FIG. 3 illustratively shows five different arrangements of the magnet arrays 231, 241 having bearings 244 and the magnet arrays 231, 241 not having bearings 244 in the housing 21 of the carrier 2.

[0047] FIG. 3a: The housing 21 supports a magnet array 231 rigidly connected and a magnet array 241 rotatably supported at rZ. While the degree of freedom rZ can be used as a drive part for the manipulator 22, the remaining five degrees of freedom X, Y, Z, rX, rY of the magnet array 241 are rigidly connected to the magnet array 231 via the bearings and the housing 21. Thus, these can be additionally used for driving the housing 21 and can expand the operating range of the force and moment that can be applied to the housing 21.

[0048] FIG. 3b: It is a view similar to FIG. 3a in which two magnet arrays 231 and 241 are concentrically arranged. In order to minimize the magnetic connection between the magnet arrays 231, 241, the inner diameter of the magnet array 231 is designed to be significantly larger than the outer diameter of the magnet array 241, so that the distance between them is maximized.

[0049] FIG. 3c: It is a view showing a housing 21 having two magnet arrays 241a and 241b rotatably supported at rZ respectively. Thus, two degrees of freedom for driving the manipulator 22 are provided on the housing 21. Corresponding to FIG. 1c, none of the magnet arrays 241 are rigidly coupled to the housing 21. Nevertheless, the housing 21 is controllable in all six degrees of freedom. In particular, this can be moved by the rotational movement of the two magnet arrays 241 about one common center of rotation at rZ.

[0050] Figure 3d: This arrangement has two magnet arrays 241a and 241b that are rotatably supported at rZ, similar to the case of Figure 3c, but they are concentrically arranged. Additionally, a fixed magnet array 231 is provided. Without the fixed magnet array 231, it would not be possible to control the housing 21 at rZ. This is because the rotation axes of 241a and 241b coincide, so it is not possible to apply a torque Mz to the housing 21. As the driven part for the concentrically arranged magnet arrays 241a and 241b, for example, two concentrically supported hollow shafts can be used.

[0051] Figure 3e: The housing 21 for driving the manipulator 22 having three degrees of freedom. It has the same structure as Figure 3c, but has three magnet arrays 241a, 241b, and 241c that are rotatably supported at rZ.

[0052] Figure 4 shows in detail the structure of the housing 21 of Figure 3a in a side view. This shows a rotary bearing 244 that guides the driven part 245 formed as a shaft. This is coupled within the housing 21 to the magnet support that supports the magnet array 241. The rotation of the magnet array 241 about the Z axis is provided to the housing 21 via the driven part 245 or transmitted to the upper surface of the housing 21.

[0053] The shaft can be coupled to the manipulator 22 via a coupling 26. Next to it is located the magnet array 231, which is fixedly coupled to the housing 21 via a magnet support 232. On the lower surfaces of the two magnet arrays 231 and 241, one code array 233 and 243 are respectively attached. Through the transparent housing bottom 212, the code arrays 233 and 243 can be read by the camera module 32 in the stator 3 (see Figure 7).

[0054] FIG. 5 shows the housing 21 of FIG. 4 in connection with a two-stage linear manipulator 22 having one degree of freedom. More precisely, FIG. 5a shows a top view of the contracted state of the linear manipulator 22, FIG. 5b shows a top view of the deployed state of the linear manipulator 22, FIG. 5c shows a side view of the contracted state of the linear manipulator 22, and FIG. 5d shows a side view of the deployed state of the linear manipulator 22.

[0055] The linear manipulator 22 shown in FIG. 5 has a linear guide as a first stage 2211 and a linear guide as a second stage 2212 attached to the first stage 2211. An end effector 222 for receiving an effective payload 4, where a wafer in the case of the semiconductor industry is illustrated here, is attached to the second stage 2212. A belt pulley 261 is mounted on a driven part 245 formed as a shaft of a magnet array 241, and the belt pulley 261 drives the two-stage linear manipulator 22 via a transmission belt 262. In the contracted state, the carrier 2 with the effective payload 4 has a very compact outer dimension. On the other hand, in the extended state, the manipulator 22 can reach a process nest in a process station PM (see FIGS. 9 or 10) that is spaced apart from the stator 3, load the wafer 4 onto this, or remove the wafer 4 therefrom.

[0056] Since the manipulator 22 can be freely positioned in its degree of freedom, the end effector 222 can also reach a process nest at an intermediate position between two end positions of the end effector 222. For applications having very high cleanliness requirements, such as the handling of wafers 4 in a vacuum, preferably, a linear guide or rolling bearing at least partially made of ceramic, or a flexure joint is used.

[0057] FIG. 6 shows the carrier 2 of FIG. 4 in connection with a bending arm manipulator 22 having one degree of freedom. More precisely, FIG. 6a shows a top view of the retracted state of the bending arm manipulator 22, FIG. 6b shows a top view of the deployed state of the bending arm manipulator 22, FIG. 6c shows a side view of the retracted state of the bending arm manipulator 22, and FIG. 6d shows a side view of the deployed state of the bending arm manipulator 22.

[0058] Like the manipulator 22 of FIG. 5, the bending arm manipulator 22 of FIG. 6 guides the payload 4 on a linear track and has a compact outer dimension in the retracted state. This manipulator 22 is also freely positionable and can reach process nests at various distances from the carrier 2. Here too, if very high cleanliness requirements are to be met, preferably ceramic bearings or flexure joints are used. The motion mechanism 221 is coupled to the housing 21 via an assembly flange 223.

[0059] FIG. 7 shows an embodiment of a conveying device according to the present invention, which is provided with the carrier 2 of FIG. 5 on the stator 3. The stator 3 is here formed from three similar stator modules. In the sectional view, the regular arrangement of the position magnets 31 and the actuators in the stator 3 can be seen, and further, the regular arrangement of the camera modules 32 that read the code arrays 233, 243 mounted on the magnet arrays 231, 241 can be seen. These code arrays 233, 243 include not only position information but also identification codes, and through this identification code, these code arrays 233, 243 can be uniquely assigned to the magnet arrays 231, 241 in a specific carrier 2. Depending on the situation, one code array 233, 243 is detected simultaneously by a plurality of camera modules 32, whereby each magnet array 231, 241 is located multiple times. This redundancy can be utilized to improve the accuracy of the position detection of the code arrays 233, 243 by averaging. The camera module 32 supplies the position data and identification data of the detected code arrays 233, 243 to the system control unit, and the system control unit obtains the actual positions of the carrier 2 and the manipulator 22 from here.

[0060] The motion control of the carrier 2 according to the present invention, which is provided with the manipulator 22, places high demands on the control of the position magnets 31 in the stator 3 with respect to the number of degrees of freedom. The carrier 2 known from the prior art usually has six degrees of freedom of motion, but the proposed mechanical carrier 2, which is provided with the manipulator 22, has more than six degrees of freedom. This number is obtained from the sum of the degrees of freedom of the housing 21 and the degrees of freedom of the manipulator 22. For example, when the manipulator 22 has one degree of freedom, the carrier 2 as a whole has seven (= 6 + 1) degrees of freedom.

[0061] FIG. 8 shows a method for controlling the movement trajectory of the carrier 2 equipped with the manipulator 22. This method is implemented in the system control unit as an algorithm. The following steps a) to e) are periodically executed in a program loop at a fixed frequency in the range of about 100 Hz to 10,000 Hz: a) The position of the carrier 2 is detected in the stator 3 or on the carrier 2 by the assigned position sensors in all degrees of freedom, in particular by the camera module 32. These sensors observe the magnet arrays 231, 241 or the code arrays 233, 243 on other moving parts, and derive the relative position between the position sensor and the code arrays 233, 243 therefrom. All position information is transmitted to the system control unit. b) A kinematic model of the transport device is stored in the system control unit, and this model describes the geometry of the components, as well as the locations of the joints, bearings, position sensors and code arrays 233, 243. Using geometric transformations, the actual positions of all the magnet arrays 231, 241 in the stator coordinate system are calculated from the model and the position sensor data. c) The position deviation of the magnet arrays 231, 241 is calculated as the difference between the actual position of the magnet arrays 231, 241 and a predetermined target position in all degrees of freedom. In order to dynamically guide the carrier 2 on the target trajectory by the manipulator 22, the target position in each loop cycle is incrementally changed according to the target trajectory. d) The position control device converts the position deviation into a vector target force and a vector target torque for each magnet array 231, 241. This is achieved, for example, using a PID algorithm applied to each of the degrees of freedom involved. e) The force control / moment control determines the target position of the position magnets 31 in the stator 3 from the vector target forces and target moments of all the magnet arrays 231, 241, the actual positions of all the magnet arrays 231, 241, the actual positions of all the position magnets 31 in the stator 3, the geometric model of all the magnet arrays 231, 241, and the physical model of the magnetic interaction. The target position is optimized such that when the target positions of all the position magnets 31 in the model are adjusted, the predicted vector forces and vector moments acting on all the magnet arrays 231, 241 match the target forces and target moments as well as possible. For this purpose, an error function is used to calculate a measure that numerically represents the deviation of the modeled forces and modeled moments from the target forces and target moments. This error function extends over all the magnet arrays 231, 241 involved and all their degrees of freedom. To minimize the error function, for example, an optimization algorithm or a neural network is used. f) Output the target angle to the actuators of the position magnets 31.

[0062] Figure 9 schematically shows a manufacturing system in the case of the semiconductor industry. The vacuum transfer space VK has a glass bottom, and since the module of the stator 3 is attached below the transfer space VK outside the vacuum region, the levitation field enters the transfer space VK through the glass bottom. In the transfer space VK, three carriers 2a, 2b, and 2c levitate in the levitation field, the carriers 2a and 2b are in a contracted state, while the carrier 2c is in an expanded state for loading the arc-shaped process nest of the process station PM. By operating a plurality of carriers 2 simultaneously in various process stations PM, a high wafer throughput is achieved. Furthermore, since the wafers 4 can be transported through the process stations PM in an individual order, various process flows can be realized in the manufacturing system in diverse production.

[0063] Figure 10 shows a method for quickly exchanging the wafer 4 in the process nest shown in an arc shape of the process station PM in four temporal steps 1 to 4, thereby minimizing the process pause between two consecutive process flows in the process station PM. For this purpose, two carriers 2a and 2b are positioned side by side in front of the process station PM. Between step 2 and step 3, the carrier 2a takes out the processed wafer 4a from the process station PM and conveys it by contracting its manipulator 22 beyond its housing 21. During the contraction movement of the carrier 2a, the carrier 2b performs an expansion movement, whereby the next wafer 4b to be processed can be introduced into the process station PM.

[0064] In this case, the contours of these wafers 4 may temporarily overlap in the X-plane / Y-plane. To avoid collisions, the end effectors 222 of the two carriers 2a, 2b are guided at different heights or different inclinations.

[0065] Figure 11a shows a method of transferring the wafer 4 from one carrier 2a to the other carrier 2b without using an intermediate storage.

[0066] In the depiction of Figure 11b, corresponding to the first variant of the method of Figure 11a, the wafer 4 is conveyed by a symmetrically constructed end effector 222a, where the center of the wafer is located in the vicinity of the side of the symmetry line of the end effector 222a. A second, similar end effector 222b is rotated by 180° and approaches from the opposite side and is guided under the wafer 4. The finger pairs of these two end effectors 222a, 222b are offset laterally, and thus they do not collide. With respect to the symmetry line of the end effector 222b, the wafer center is offset laterally. The transfer is performed by the upward movement of the end effector 222b and the downward movement of the end effector 222a.

[0067] In the depiction of FIG. 11c, corresponding to the second variant of the method of FIG. 11a, each finger is attached to the end effectors 222a, 222b slightly asymmetrically, and thus the two end effectors 222a, 222b, which are shifted 180° relative to each other, can move towards each other along the virtual center line without colliding with each other.

[0068] FIG. 12 shows a method of delivering the wafer 4, the angular position of which can be changed over the entire range of 360°. For this purpose, a transfer is made from a first carrier 2a equipped with a manipulator 22 to a second carrier 2b formed as a circular disk or having a circular surface on its upper surface. The second carrier 2b receives the wafer 4 centrally (step 2). The second carrier 2b is used as an intermediate storage for the wafer 4. Here, the wafer 4 is rotated by a predetermined angle about the Z axis (step 3). Thereafter, a third carrier 2c equipped with a manipulator 22 receives the wafer 4 in a new orientation (step 4).

[0069] Another variant for orienting the rotational position of the wafer 4 by means of a single carrier 2 will be described below. The carrier 2 incorporates two manipulators 22. The first manipulator 22 has two degrees of freedom, one degree of freedom for the contraction / expansion of the end effector 222 in the radial direction (as described above) and another degree of freedom for the lift of the end effector 222 in the Z direction. The second manipulator 22 is responsible for orienting the rotational position of the wafer 4. This has degrees of freedom, rotation about the Z axis perpendicular to the transport plane, and an end effector 222 for receiving the wafer 4 at the center. Thereby, the wafer 4 positioned on the end effector 222 can be rotated about its own center point. With this arrangement, with a single carrier 2, the wafer 4 can be taken out from the process nest, transported, the rotational position can be oriented during transportation, and the wafer 4 can be placed at a predefined rotational position at the target location. For this purpose, the following movement flow is provided. a) Removal of the wafer 4 from the process nest: At the supply location, the first manipulator 22 moves its end effector 222 under the wafer 4 located in the process nest. After the lift movement, the wafer 4 is positioned on the end effector 222. b) Contraction movement of the first manipulator 22: Next, the wafer 4 is positioned above the carrier 2, and below the wafer 4, the second manipulator 22 is centered and positioned at this time. c) Transfer of the wafer 4 from the first manipulator 22 to the second manipulator 22 by the downward movement of the first manipulator 22 d) Orientation of the rotational position of the wafer 4 by the rotation of the second manipulator 22: A sensor may be provided for the orientation regarding the notch at the edge of the wafer 4 (notch), and this sensor monitors the position of this notch during the rotational movement. e) Transfer of the wafer 4 from the second manipulator 22 to the first manipulator 22 by the lifting movement of the first manipulator 22: At this point, the wafer 4 is positioned on the first manipulator 22 at a predefined rotational position. f) Placement of the wafer 4 at the target location by the first manipulator 22.

[0070] A transfer device designed to transfer one or more effective payloads 4, in particular wafers, by means of a carrier 2 is disclosed. The carrier 2 floats on the transfer surface 33 of the stator 3 and is movable and positionable. Preferably, movement and positioning are performed with respect to all six degrees of freedom. The carrier 2 has a movable boom or a movable manipulator 22 or a movable robot arm. It is possible to place or fix the effective payload 4 on its end effector 222. In a developed form, the effective payload 4 can also be processed and / or inspected. This processing and / or inspection can also be carried out by the end effector 222 of another carrier 2 of the same transfer device.

Explanation of Signs

[0071] 2 Carrier 21 Housing 212 Housing bottom 22 Manipulator 221 Movement mechanism 2211 First stage 2212 Second stage 222 End effector 223 Assembly flange 23 Drive unit (for the housing) 231 Magnet array fixed to the housing 232 Magnet support 233 Cable array (for the housing) 24 Drive unit (for the manipulator) 241 Magnet array (movable with respect to the housing) 243 Cable array (for the manipulator) Bearing (for the magnet array with respect to the housing) 245 Driven part 25 Electronic unit 251 Energy accumulator 252 Communication interface 253 User interface 26 Coupling 261 Belt pulley 262 Transmission belt 3 Stator 31 Position magnet 32 Camera module 33 Conveyor surface 4 Effective payload / wafer LL Load lock PM Process station VK Conveyor space

Claims

1. A conveying device for conveying at least one effective payload (4), wherein at least one carrier (2, 2a, 2b) is assigned to each effective payload (4), and the carrier (2, 2a, 2b) floats on the conveying surface (33) of the stator (3) and is movable and positionable, a boom or manipulator (22) or robot arm extends between the end effector (222) of the carrier (2) and the housing (21), in the conveying device, the end effector (222) can be operatively coupled to the effective payload (4), the boom or manipulator (22) or robot arm realizes and controls at least one first degree of freedom of movement of the end effector (222) with respect to the housing (21), in the retracted state of the boom or manipulator (22) or robot arm, the center point of the effective payload (4) is, or the effective payload (4) is partially, or the effective payload (4) is completely, disposed on the housing (21) of the carrier (2), A conveying device characterized by this.

2. The conveying device according to claim 1, wherein the first degree of freedom of movement is a degree of freedom of movement that can be positioned with respect to the housing (21) of the carrier (2) during the floating movement of the carrier (2).

3. The conveying device according to claim 1 or 2, wherein the operative coupling is support and / or operation and / or positioning and / or fixing and / or processing and / or inspection that can be performed by the end effector (222) on the effective payload (4).

4. The conveying device according to any one of claims 1 to 3, wherein the boom or manipulator (22) or robot arm has a motion mechanism (221) comprising at least two stages (2211, 2212) or sections.

5. The conveying device according to claim 4, wherein the stages (2211, 2212) or sections are linearly displaceable or rotatable relative to each other.

6. The conveying device according to any one of claims 1 to 5, wherein a plurality of process stations (PM) for processing the effective payload (4) are arranged in the vicinity laterally of the conveying surface (33).

7. A process nest is arranged in the process station (PM), and the process nest is laterally spaced from the conveying surface (33), The separation according to claim 6, wherein the boom or manipulator (22) or robot arm can bridge in the deployed state of the boom or manipulator (22) or robot arm.

8. At least one magnet array (231) is received and attached in the housing (21) of the carrier (2), and the at least one magnet array (231) can magnetically interact with the stator (3) and can be moved by the stator (3). The conveying device according to any one of claims 1 to 7.

9. At least one magnet array (241) is movably received in the housing (21) of the carrier (2), and the at least one magnet array (241) is mechanically connected to the boom or manipulator (22) or robot arm. The at least one magnet array (241) can magnetically interact with the stator (3) and can be moved by the stator (3). The conveying device according to any one of claims 1 to 8.

10. The magnet array (241) is rotatably supported by a bearing (244). A belt pulley (261) is attached or connected to the magnet array (241) so as not to rotate relative to the magnet array (241), and the belt pulley (261) is mechanically connected to the boom or manipulator (22) or robot arm via a transmission belt (262). The conveying device according to claim 9.

11. The conveying device has two carriers (2), and the end effectors (222a, 222b) of the two carriers (2) are laterally displaced and can move towards each other. The conveying device according to any one of claims 1 to 10.

12. The conveying device has two carriers (2), and the end effectors (222a, 222b) of the two carriers (2) have two asymmetric fingers. The conveying device according to any one of claims 1 to 10.

13. The conveying device has an additional carrier (2b), and the housing (21) of the additional carrier (2b) is a rotatable disk or has a rotatable disk. The conveying device according to any one of claims 1 to 12.

14. A transport space (VK) is formed on the transport surface (33), and a gas or gas mixture or liquid or vacuum or ultra-high vacuum or sterile area or ABC protection area is provided in the transport space (VK). The transport device according to any one of claims 1 to 13, wherein the at least one carrier (2) is received in the transport space (VK).

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