Handling workpieces, in particular wafers

Abstract

The invention relates to a system for handling workpieces A or an arrangement formed of multiple systems of this type. The system according to the invention for handling workpieces A comprises a housing, delimiting a handling chamber B, in which there is a controlled atmosphere, with a gas-tight casing (1) which separates the controlled atmosphere from the atmosphere outside the casing (1). The system for handling workpieces A has a conveying system with which workpieces can be conveyed in a handling chamber, as well as at least one coupling means (10) that is coupled to at least one coupling unit (20) of the conveying system. The coupling means (10) and the coupling units (20) are contactlessly coupled to one another through the gas-tight casing (1). The coupling means (10) are designed as electromagnetic stators (11) outside the gas-tight casing (1). The conveying system has at least one carrier (30) which has at least one permanent magnet (21) as a coupling unit (20) and with which workpieces can be conveyed in the handling chamber B. With the cooperation of the coupling means (10) and the coupling units (20), the carrier (30) can be contactlessly held in suspension relative to the casing (1) and can be conveyed in the handling chamber B. The invention is characterised by particular operational safety and high product safety.

Description

[0001] Treatment of workpieces, especially wafers

[0002] TECHNICAL FIELD

[0003] The invention relates to systems for treating workpieces, in particular wafers, to carriers for such a system for treating workpieces and to methods for transferring a workpiece to or from such a carrier.

[0004] STATE OF THE ART

[0005] DE 10 2009 038 756 A1 discloses a device for particle-free handling of substrates in microstructure technology within mini-environments under ultraclean room conditions. In order to achieve a particle-free operating device for handling substrates in microstructure technology, several degrees of freedom are provided, of which at least the x, y, z and t> axes are magnetically mounted and / or guided in a contact-free manner, wherein the mounting and drive of the individual axes are effected electromagnetically without contact and wherein the energy for the mounting and the drive is transmitted contact-free and at least one active part and at least one passive part are provided in each case, wherein a movable active part is guided suspended from a stationary passive part by means of magnetic bearings and wherein a traveling drive motor located on the active part is connected to an energy source via an electromagnetic coupling unit.This device is complicated to handle and requires considerable effort to implement.

[0006] DE 10 2011 116 136 A1 discloses a system for treating substrates for photovoltaic thin-film cells. These substrates are processed in a treatment room with a controlled atmosphere. The treatment room is enclosed in a gas-tight manner. The system contains a conveyor system with rotating shafts that transport the thin-film cells by rotation inside the treatment room. The drive, i.e. the rotational movement of the shafts, is transferred contactlessly via coupling elements from a shaft located outside the treatment room to the shafts inside the treatment room. This system has proven to be functional but has weaknesses in operational reliability and damage to the thin-film cells due to the abrasion generated by the rotating shafts for transport.

[0007] From DE 20 2021 106 150 U1 a system for treating workpieces according to the preamble is known. This shows a housing with a shell which delimits a treatment chamber and which separates the controlled atmosphere of the treatment chamber from the atmosphere outside the shell. The system for treating workpieces has a conveyor system, by means of which workpieces can be conveyed in a treatment chamber, and at least one coupling means which is coupled to at least one coupling unit of the conveyor system. The coupling means and the coupling units are coupled to one another without contact through the gas-tight shell. The coupling means are designed as electromagnetic stators outside the gas-tight shell. The conveyor system has at least one carrier which has at least one permanent magnet as a coupling unit and by means of which workpieces can be conveyed in the treatment chamber.Through the interaction of the coupling means and the coupling units, the carrier can be suspended without contact with the shell and transported into the treatment chamber. Additional robots in the lock place the workpieces to be processed onto the carrier, allowing them to be brought from the carrier through the lock into the treatment chamber and transported there. This arrangement proves to be complex and cumbersome to handle.

[0008] DESCRIPTION OF THE INVENTION

[0009] The invention is based on the object of providing a system for treating workpieces that is improved over the prior art, or a carrier for such a system, or a method for transferring a workpiece to or from such a carrier. This system should be characterized by simple handling and low outlay. Furthermore, the aim is to enable exceptional operational reliability and high product safety.

[0010] This object is achieved according to the invention by a system for treating workpieces which has the features specified in claim 10. This object is further achieved according to the invention by a carrier for a system for treating workpieces which has the features specified in claim 1. Furthermore, this object is achieved according to the invention by a method for transferring a workpiece to or from a carrier which has the features specified in claim 13. Advantageous embodiments of the invention are the subject of the dependent claims.

[0011] The carrier according to the invention is designed and provided for a system for treating workpieces, in particular wafers, which system is provided with a housing which delimits a treatment chamber in which a controlled atmosphere is present and which comprises a gas-tight envelope, the envelope separating the controlled atmosphere from the atmosphere outside the envelope. The system has a conveyor system by means of which workpieces can be conveyed in the treatment chamber and is provided with at least one coupling means which is coupled to at least one coupling unit of the conveyor system. The gas-tight envelope is present between the coupling means or means and the coupling unit or units and these are coupled to one another without contact through the gas-tight envelope.Furthermore, the coupling means is or are designed as electromagnetic stators outside the gas-tight casing, and the conveying system has at least one carrier, by means of which workpieces can be conveyed into the treatment chamber. The carrier has at least one permanent magnet as a coupling unit and, through the interaction of the at least one coupling means and the at least one coupling unit connected to the carrier, can be kept suspended in suspension without contact with the casing and can be conveyed into the treatment chamber. At least one carrier is provided with a holder for an effector and has such an effector which is firmly connected to the carrier by means of the holder. The effector is designed such that it projects laterally beyond the carrier and is provided for laterally receiving the workpieces to be treated.This ensures that the workpiece to be treated is not placed above the carrier for conveying but is held at least substantially to the side by means of the effector, thereby enabling conveying in the system, particularly in the treatment room. This carrier therefore demonstrates a different type of conveying in a system for treating workpieces, particularly wafers, than in the prior art. This becomes particularly clear when transferring a workpiece to or from a carrier with such an effector, because the carrier does not have to be brought under the workpiece for pickup, nor does the workpiece to be treated have to be placed on or lifted off the carrier.This makes it possible for the free height at the point of transfer of a workpiece to or from a carrier with an effector to have a lower height than the carrier and thus in particular in the area of ​​the height of the narrower effector, without the transfer being hindered as a result.

[0012] The treatment chamber is designed to be capable of maintaining a vacuum using the enclosure or, alternatively or additionally, of providing a protective gas atmosphere. All types of products or intermediate products that can be processed and treated in an environment with such a controlled atmosphere have proven suitable as workpieces. This system is particularly well-suited for the treatment of semiconductor, sensor, and optical substrates.

[0013] By providing such a carrier with an effector, which is suitable for statically safely receiving the workpiece to be treated and for conveying it with the carrier in suspension into or through the treatment room, it is possible to ensure very safe and very low-damage transport and thus conveyance of the workpiece to be treated.

[0014] By designing the conveyor system of such a system on the one hand with one or more magnetic coupling units designed as permanent magnets on or in the carrier with effector and on the other hand with one or more coupling means arranged as electromagnetic stators outside the gas-tight casing, which interact in such a way that the carrier with the effector can be kept in suspension or lifted without contact with the casing and can be conveyed in the treatment room, it is possible, on the one hand, to design the carrier without cables and control lines,to simplify the handling of the carrier, particularly when transferring a workpiece to the carrier with effector or from this carrier with effector and for conveying the workpiece, and to design the conveying process with minimal damage to the workpiece and, on the other hand, to minimize the risk of damage to the gas-tight enclosure and thus of malfunctioning the system, for example due to leaks, and thereby create an extremely safe system for the treatment of workpieces in a controlled sphere.

[0015] This is achieved, among other things, by providing a closed, gas-tight enclosure formed between the coupling unit(s) and the coupling means(s). The coupling means, designed as electromagnetic stators, are controlled such that the at least one carrier with effector is held suspended in the treatment chamber, regardless of whether the workpiece is arranged on the effector or not on the carrier. The same applies to the conveying of the at least one carrier with effector, with conveying occurring primarily in a lateral direction. In addition to this conveying, it is also optionally possible to provide a vertical movement or guidance in various directions or rotation about the vertical of the carrier with effector. This is preferably ensured by a corresponding sensor and control circuit for controlling the coupling means.

[0016] It has proven particularly useful to develop the device according to the invention in such a way that the effector projects beyond the carrier by at least the width of the carrier, in particular by several times the width of the carrier. The width is the lateral extent of the carrier, which in the case of a rectangle is selected to be smaller than the length. As a result of this significant lateral projection beyond the carrier, the lateral offset for receiving the workpiece on or against the effector is particularly large, so that the advantageous movement under the position of the workpiece to be machined during transfer is particularly easy, in particular when the transfer area has a low overall height. Due to the great length of the lateral projection, tilting the carrier by appropriate control using the coupling means and the associated control system has a particularly advantageous effect and enables an even lower height of the transfer area.This creates a particularly advantageous possibility for varying the design of the system with the potential transfer areas.

[0017] In this case, it has proven particularly useful to further develop the carrier according to the invention in such a way that the carrier with the effector is designed to be movable in at least four degrees of freedom, with the possibility of a displacement in the three independent directions x, y and z directions and additionally the possibility of a rotational movement about at least one of the three independent axes of rotation Rx, Ry and Rz axes being provided. In particular, the possibility of a displacement in the three independent directions x, y and z directions and the possibility of a rotational movement about all three independent axes of rotation Rx, Ry and Rz axes is provided, thus creating the possibility of moving the carrier with the effector in six degrees of freedom.By providing a possibility of movement about at least one axis of rotation such as the axis of rotation Rx or Ry, i.e. the horizontal axes of rotation, it is possible to incline the carrier with the effector and thus to lower the front end of the effector with the holder for the workpiece to be machined, whereby the necessary construction height of the transfer area of ​​the system can be advantageously reduced.

[0018] It has proven particularly useful to further develop the carrier according to the invention in such a way that the effector is flat with a maximum height of 4 cm. A height in the range of 1 to 2 cm has proven particularly advantageous. This design provides, on the one hand, good mobility in the treatment chamber and in the transfer area of ​​the system and, on the other hand, the option of lowering the front end of the effector with the holder for the workpiece creates the option of enabling safe passage and conveying through areas of the treatment chamber with reduced height. This creates, on the one hand, particularly safe handling and, if necessary, the option of designing the system in a more versatile way. This is all the more true since low treatment chamber heights and thus reduced volumes increase operational reliability by reducing the risk of leaks.In addition, this training makes it possible to reduce cycle times by shortening the pumping or cycle times for such a system for treating workpieces and thus to improve the efficiency of treating workpieces in such a system.

[0019] It has proven particularly useful to develop the carrier according to the invention in such a way that the effector has a fork-shaped structure. This preferably has a plurality of, in particular two, legs running parallel to one another, which define a plane and are suitable for holding the workpiece, in particular a wafer, in this plane. The legs of the fork-shaped structure preferably have three support points which together define a support plane and have a low but sufficient height to enable the workpiece to be transferred securely to or from the carrier or to or from the effector of the carrier. Preferably, one of these three points is arranged in the end region of each of two legs and one in the middle region of the connecting piece of these two legs.

[0020] It has proven particularly useful to further develop the carrier according to the invention in such a way that the effector is designed to be detachable from the holder on the carrier. This design of the effector allows different effectors with different dimensions and, in particular, with different arrangements and designs of the support points to be selected and exchanged as required, particularly depending on the different workpieces to be treated. This ensures particularly safe handling during operation or when using the carrier in such a system for treating workpieces.

[0021] It has proven particularly useful to further develop the carrier according to the invention in such a way that the carrier with the effector is provided with a measuring system for determining the load on the effector and / or the carrier, in particular by the applied workpiece to be treated. This makes it possible, on the one hand, to determine the extent of necessary maintenance or damage to the carrier or the effector, and thus to increase operational reliability. On the other hand, it also creates the possibility of designing the transfer of a workpiece to or from such a carrier in a differentiated manner depending on the extent of the load, in particular the extent of the weight load.Preferably, a measuring system is selected which determines the weight load of the effector or the bending or stretching on the effector caused by the applied weight of the workpiece and feeds this to a control of the system for treating the workpiece with the carrier with measuring system, so that this control of the system, in particular the carrier with the effector, is controlled differently.

[0022] It has proven particularly useful to further develop the carrier according to the invention in such a way that the effector and the carrier are passive, i.e. without an active drive. This design of the carrier with the effector arranged thereon creates a simple and robust arrangement which is particularly characterized by its low weight and can therefore be moved particularly easily and precisely using the conveyor system. In particular, this design enables very precise adjustment of the inclination of the carrier with the effector arranged thereon by rotation about one of the two horizontal axes of rotation, thus achieving process reliability, particularly during the transfer of the workpiece.

[0023] Alternatively, it has also proven advantageous to further develop the carrier according to the invention such that the effector connected to the carrier is provided with a drive for changing its length, its alignment, and / or its position for the workpiece. This makes it possible to react flexibly and without complex modifications to the system using the carrier with effector to different workpieces to be treated and to ensure safe transfer to the effector or safe conveyance within the system, particularly through the treatment chamber.

[0024] The system according to the invention for treating workpieces, in particular wafers, is provided with a housing which delimits a treatment chamber in which a controlled atmosphere is present, and which comprises a gas-tight envelope, the envelope separating the controlled atmosphere from the atmosphere outside the envelope. The system has a conveyor system by means of which workpieces can be conveyed in the treatment chamber and is provided with at least one coupling means which is coupled to at least one coupling unit of the conveyor system. The gas-tight envelope is present between the coupling means or means and the coupling unit or units, and these are coupled to one another without contact through the gas-tight envelope.Furthermore, the coupling means is or are designed as electromagnetic stators outside the gas-tight casing, and the conveying system has at least one carrier, by means of a carrier workpieces can be conveyed into the treatment chamber. The carrier has at least one permanent magnet as a coupling unit and, through the interaction of the at least one coupling means and the at least one coupling unit connected to the carrier, can be kept suspended in suspension without contact with the casing and can be conveyed into the treatment chamber. The at least one carrier is provided with a holder for an effector and has such an effector which is firmly connected to the holder of the carrier. The effector is designed such that it projects laterally beyond the carrier and is provided for laterally receiving the workpieces to be treated.This ensures that the workpiece to be treated is not placed above the carrier for conveying but is held at least substantially to the side by means of the effector, thereby enabling conveying in the system, particularly in the treatment room. This carrier of the system therefore demonstrates a different type of conveying in a system for treating workpieces, particularly wafers, than in the prior art. This becomes particularly clear when transferring a workpiece to or from a carrier with such an effector, because the carrier does not have to be brought under the workpiece for pickup, and the workpiece to be treated does not have to be placed on or lifted off the carrier.This makes it possible for the free height at the point of transfer of a workpiece in the system to or from a carrier with an effector to have a lower height than the carrier and thus in particular in the area of ​​the height of the narrower effector, without the transfer being hindered as a result.

[0025] It has proven particularly useful to further develop the system for treating workpieces according to the invention in such a way that it has at least one further carrier for conveying workpieces in the system, which is provided with a holder for the workpiece which is intended to hold the workpiece to be treated above the carrier. The differentiated design of the carriers of the system for treating workpieces, in particular wafers, creates a particularly diverse transport option which can be selected as needed, in particular depending on the workpiece to be conveyed, which increases operational reliability and, on the other hand, reduces the need to adapt the system to changed conditions, in particular changed workpieces, which requires or suggests a differentiated design of the carriers.

[0026] Furthermore, it has proven particularly useful to further develop the system for treating workpieces according to the invention so that it has a control system that enables the transfer of a workpiece from one carrier with an effector to another carrier without an effector, or vice versa. This design of the system makes it possible for the workpiece to be conveyed in a differentiated manner using different carriers within the system, and thus for conveying in the system to be possible with differentiated carriers depending on the respective different conditions within the system, particularly in the treatment room.This further development makes it possible to change the carrier for conveying the workpiece to be treated. For example, the control system controls the carrier with the effector in such a way that the effector, with its holder, lifts the workpiece from the carrier without the effector and thereby enables the transfer from one carrier to the other. The same is also possible in reverse. This type of system control ensures that the system is particularly flexible. In particular, the carrier for conveying the workpiece can be selected and adapted as required, particularly depending on the conditions in the area of ​​the system through which the workpiece is conveyed.This also makes it possible to simplify the handling of the system and, on the other hand, to increase operational reliability, since the need to modify the system, particularly the treatment room, to adapt it to different workpieces or changed conditions can be limited.

[0027] A method according to the invention for transferring a workpiece to or from a carrier with an effector shows at least three phases, an approach phase, a transfer phase and a vertical phase.

[0028] In the approach phase, the effector and its holder are moved beneath the workpiece to be treated and raised until they first make contact. Then, in the transfer phase, the orientation of the effector holder is pivoted so that several points of contact are created. Finally, in a vertical phase, the workpiece to be treated is lifted by vertical displacement and lifted off the support on which the workpiece is prepared for transfer. By lifting the workpiece with the help of the effector, the workpiece comes to rest in the effector holder and can then be conveyed into and through the system or the system's treatment area. The differentiated handling in the three phases makes it possible to reduce the load on the workpiece, particularly on a wafer, by reducing or preventing one-sided loads on the wafer or bending of the wafer.The approach phase and the differentiated transfer phase are particularly important here, as the load on the workpiece can be kept to a minimum in the approach phase and can be kept just as low in the transfer phase. In the vertical phase, the workpiece is supported at several contact points and thus, in a particularly even manner, and is accordingly lifted with little load on the workpiece and finally inserted into the reflector holder. This makes it possible to increase the process reliability and operational safety of the system for treating a workpiece, in particular a wafer, when using the method according to the invention.

[0029] The same applies to transferring the workpiece from the carrier with effector. In an approach phase, the effector with its holder and the workpiece arranged therein is moved into the area of ​​the support and thus to the transfer point and the workpiece is lowered there until it first touches the support. In a subsequent transfer phase, the orientation of the effector holder with the workpiece arranged therein is swivelled so that several points of contact between the workpiece and the support are created. Then, in a vertical phase, the workpiece is lowered by vertical displacement and placed on the support. After that, the released effector holder, which is no longer connected to the workpiece, can be removed from the support and used for further conveying processes.This makes it possible to increase the process reliability and operational safety of the system for treating a workpiece, in particular a wafer, when using the method according to the invention.

[0030] It has proven particularly useful to develop the method according to the invention for transferring a workpiece in such a way that the transfer phase takes place exclusively by rotational movements of the effector and / or the effector holder. By rotating exclusively and thus avoiding displacements in the X direction or Y direction or Z direction, it is possible to increase the number of contact points significantly without any lifting occurring due to the effector holder or the support in the transfer area. The carrier with the effector and its holder is moved by the system control system in such a way that the support plane in the effector holder is adapted to the support plane of the support in the transfer area by the rotational movements alone and the number of contact points without lifting is increased considerably and in particular is selected to be maximum.This increase in the contact points without lifting ensures a statically well-defined position of the workpiece, in particular the wafer, during transfer from the effector holder to the support in the transfer area, or vice versa. This statically well-defined position enables subsequent vertical lifting or lowering of the workpiece or wafer with very little load on the workpiece. This makes it possible to increase the process reliability and operational safety of the system for treating a workpiece, in particular a wafer, when using the method according to the invention.

[0031] It has proven particularly useful to further develop the method according to the invention for transferring a workpiece in such a way that the approach phase and / or the vertical phase take place exclusively by moving the effector and / or the holder of the effector. The moving movement can take place either by moving the carrier with effector through the conveyor system or by an active drive on the carrier or on the effector, which moves the holder on the effector in one direction without any torsional or rotational movement occurring. This simple moving movement of the effector or the holder of the effector makes it possible to ensure a very simple and safe moving movement which, in contrast to a rotary movement or pivoting movement, enables less stress and a lower risk of damage to the workpiece.This makes it possible to maintain high levels of process reliability and operational safety.

[0032] It has proven particularly useful to further develop the method according to the invention for transferring a workpiece in such a way that, during the transfer phase, the effector and / or the holder of the effector are pivoted in such a way that at least three spaced-apart points of contact between the workpiece and the holder of the effector preferably lie in a common plane defined by the at least three points of contact. This takes place without lifting a point of contact of the workpiece through or from the support. By choosing the contact points in this way, it is possible to bring the support plane of the workpiece into line with the support plane of the holder on the effector or on the support in a very reliable manner and thus to keep the load on the workpiece, for example due to bending of the workpiece when it is lifted, to a particularly low level.In addition, it is possible to make the handling of the workpiece during transfer particularly simple and safe, thus maintaining high levels of operational safety and process reliability.

[0033] It has proven particularly useful to further develop the device according to the invention such that the at least one carrier with effector has a support structure with at least one receiving space enclosed by webs for at least one permanent magnet. This receiving space is preferably designed to face the at least one coupling means. By designing the carrier with effector in this way, it is possible to create a very rigid carrier and at the same time a safe and stable means of transport for the workpiece to be machined, because the support structure with the webs ensures the pronounced rigidity of the carrier and securely accommodates the at least one coupling unit designed as a permanent magnet, thus enabling reliable levitation and conveyance of the carrier or the workpiece.By orienting the receiving space in the carrier in the direction of at least one coupling unit, it is possible to enable very efficient control of the hovering and conveying, since on the one hand the distance and on the other hand the number of possible disturbing objects between the coupling elements of the conveying system are limited.

[0034] In addition, it has proven particularly useful to further develop the system in such a way that the at least one support with effector has a supporting structure made of light metal, which is in particular formed as a milled part and / or from aluminum, an aluminum alloy or a magnesium alloy. This makes it possible to avoid disruptive outgassing and thus a negative influence on the controlled atmosphere, in particular the vacuum, while keeping the weight of the support with effector low, and thus to particularly guarantee the operational reliability of the system. This is ensured in particular by this design of the supporting structure without plastics and exclusively from metal, in particular from light metals.

[0035] In addition, it has also proven to be advantageous to further develop the system for the treatment of workpieces in such a way that the gas-tight shell has a floor that separates the coupling agents from the treatment chamber with the carrier and the effector, and is made of stainless steel or aluminum in the area of ​​the coupling agents. This makes it possible in a special way to design the floor as part of the gas-tight shell to be particularly gas-tight. It has proven particularly preferable to cover the stainless steel or aluminum in the area of ​​the coupling agents with a

[0036] Wall thickness of approximately 0.5 mm or less. This makes it possible to limit the distance and the influence of the floor on the magnetic field between the coupling elements of the conveyor system and thus on the carrier for conveying the workpiece to be treated, thus creating a very efficient conveying system for the plant with a gas-tight enclosure.

[0037] A particularly preferred development of the system shows the possibility that the base made of stainless steel or aluminum encloses the coupling means in a U-shape in the area of ​​the coupling means(s) and at least partially accommodates the coupling means. This makes it possible for the coupling means to be mechanically stable and enclosed by the stainless steel or aluminum in a U-shape, so that the coupling means form a single unit with the stainless steel or aluminum of the base and are thus mechanically robust and also arranged close to the gas-tight shell or the base and designed to be gas-tight.

[0038] A preferred development of the system according to the invention for treating workpieces shows a lock with at least one movable lock wall which is suitable for separating the treatment chamber from the lock chamber in a gas-tight manner in a closed position or for making it passable in an open position. The lock wall can be moved from the open position to a closed position or vice versa by means of a vertical and subsequent lateral movement. Furthermore, the lock wall is sealed in a closed position against the shell in the transition area to the treatment chamber on the lock chamber side by means of at least one O-ring seal, so that the treatment chamber and the lock chamber are separated from one another in a gas-tight manner.This special L-shaped movement of the lock allows the movable lock wall to move efficiently and, especially when there is a significant pressure differential between a vacuum in the treatment chamber and the lock chamber and the outside atmosphere, for example, when filling the lock, to achieve and ensure a very secure, gas-tight separation of the treatment chamber. In this case, the outside atmosphere acts as a supporting momentum to generate the necessary sealing force on the movable lock wall.

[0039] A particularly preferred development of the system for treating workpieces features coupling means arranged in the floor, which are located both in the area of ​​the lock chamber and in the area of ​​the treatment chamber. At least one coupling means is arranged in the area of ​​the treatment chamber, at least partially beneath the casing section of the lock, which is connected to the rest of the casing. This arrangement of the coupling means, which are designed in particular as electromagnetic stators, enables the most uniform and efficient transport possible and thus the uniform and efficient conveyance of the carrier from the treatment chamber into the lock or back.

[0040] According to a preferred development of the system for treating workpieces, the system is provided with a control system for controlling the coupling means which is suitable for keeping a carrier with an effector suspended and for conveying it in the treatment chamber and / or lock chamber of the system, while pivoting the carrier with the effector in the X direction, in the Y direction and / or in the Z direction as well as in the directions of rotation about the Rx, Ry and / or Rz axis of rotation. This is made possible by a corresponding sensor and control circuit for controlling the various coupling means. This control system for the individual system for treating workpieces creates an advantageous and robust arrangement which enables reliable operation of the system and, thanks to the uniform design, can also be implemented cost-effectively and with optimized production.

[0041] The invention is explained below using preferred embodiments with reference to the figures. The invention is not limited to these preferred embodiments.

[0042] Fig. 1 shows a schematic sectional view of an exemplary system according to the invention for the treatment of workpieces,

[0043] Fig. 2 shows a schematic sectional view of an exemplary carrier with effector of a system according to the invention for treating workpieces,

[0044] Fig . 3 shows in a schematic plan view the

[0045] Carrier with ef fector from Figure 2 ,

[0046] Fig. 4a shows a schematic flow diagram of an exemplary method for transferring a workpiece from a support to a carrier with an effector from a support and

[0047] Fig. 4b shows a schematic flow diagram of an exemplary method for transferring a workpiece from a carrier with an effector to a support. Fig. 1 schematically shows a system A for treating workpieces. System A shows a housing which defines a treatment chamber B in which a controlled atmosphere with a very low pressure, also called a vacuum, exists and which is enclosed by a gas-tight casing 1.

[0048] Plant A features two different areas: a lock S and a plant area with the treatment room B, which can be separated from each other by a lock wall SW. Workpieces can be fed into plant A via the lock S, whereby this occurs via a conventional lock process with sequential opening and closing of the access opening Z or the lock wall SW to the treatment room B.

[0049] In the lock S, a carrier 30 without an effector is shown, which floats in the space of the lock S and is therefore without contact with the shell 1 including the floor 2. With the help of the carrier 30 without an effector, workpieces can be conveyed in the system A on the surface of the carrier 30 or in a receptacle on the surface. With the help of the carrier 30a with an effector 35, which has a receptacle 38 for the workpiece to be treated, workpieces to be treated can be conveyed efficiently in the system A and through it.

[0050] This is made possible by a conveying system which has coupling means 10 which are designed as electromagnetic stators 11 and coupling units 20 which are designed as permanent magnets 21, wherein these coupling elements 10, 11, 20, 21 interact magnetically with one another such that the carrier 30, 30a can be kept suspended and can be conveyed from one position to another in the lock chamber SR or the treatment chamber B. In order to achieve this, the carrier 30, 30a is provided with permanent magnets 21 as coupling units 20 and the base 2 as part of the gas-tight casing 1 is provided with electromagnetic stators 11 as coupling means 10. With the aid of a control system (not shown), the coupling means 10 are controlled and regulated such that the carrier 30 can be kept suspended and can be conveyed.

[0051] The base 2 of the gas-tight casing 1 contains a plurality of stainless steel or aluminum regions 2a which are formed from a stainless steel or aluminum plate with a thickness of just under 0.5 mm and which are assigned to the various electromagnetic stators 11 and enclose them in a U-shape, partially accommodate the electromagnetic stators 11 in a secure manner and spatially and sealingly separate them from the lock chamber SR or the treatment chamber B. The edges of the stainless steel or aluminum regions 2a are designed as collars 8 which adjoin the U-shaped ends of the stainless steel or aluminum regions 2a and are aligned with the adjacent collars 8. The electromagnetic stators 11 which are at least partially accommodated in the stainless steel or aluminum regions 2a are connected to one another over their surface by means of a low-viscosity adhesive 3 and are thus secured.

[0052] Furthermore, the base 2 contains connecting pieces 2b, which connect the individual stainless steel or aluminum sections 2a such that the base 2 has a flat surface. An O-ring seal 7 is inserted between the connecting pieces 2b and the collars 8 of the stainless steel or aluminum sections 2a.

[0053] Below the collar 8 of the stainless steel or aluminum areas

[0054] 2a in the area of ​​the treatment room B, a common rigid frame 5 made up of several stiffeners 4 is arranged, which is screwed to the connecting pieces 2b via a series of screws 6 in such a way that the collars 8 of the stainless steel or aluminum areas 2a are held in a clamped and sealed manner with the O-ring seals 7 between the connecting pieces 2b and the common, rigid frame 5.

[0055] The floor 2 has a similar structure not only in the area of ​​the treatment room B but also in the area of ​​the lock S, which on the one hand proves to be gas-tight and on the other hand, thanks to the stiffeners 4 below the stainless steel or aluminum areas 2a, proves to be extremely robust and stable against the stresses caused by the controlled atmosphere in the treatment room B, despite the low material thickness of the stainless steel or aluminum areas 2a.

[0056] The coupling means 10 and the coupling units 20 are thus separated from one another by the gas-tight stainless steel or aluminum regions 2a, which are part of the base 2 and thus of the casing 1, and are nevertheless able to interact magnetically in such a way that the carrier 30, 30a can be held suspended and conveyed. The carrier 30, 30a can be moved linearly in all three directions, the X direction, the Y direction and the Z direction (displacement), but can also be rotated and thus pivoted in the corresponding three directions of rotation, the Rx, Ry and Rz directions. It is precisely this pivoting that enables the carrier 30a to be inclined with the effector 35 projecting laterally beyond the carrier 30a. This tilting enables a reduction of the necessary construction height in the area of ​​the transfer of a workpiece from or to the carrier 30a with the effector 35.The coupling units 20 are arranged on the support 30, 30a and are thus located in the treatment room B or in the associated lock room SR, while the coupling means 10 are arranged outside the gas-tight casing 1, i.e. on the side of the stainless steel or aluminum areas 2a which is facing away from the treatment room B or the lock room SR.

[0057] The lock S with its floor 2, which has a comparable structure to the floor 2 in the area of ​​the treatment room B, also has a movable lock wall SW, an access opening Z, which are connected to one another via a gas-tight shell 1, and a shell section 42 which is gas-tightly connected to the remaining gas-tight shell 1 of the system A in the area of ​​the treatment room B. The movable lock wall SW, including its drive, is integrated gas-tight into the shell 1 of the lock S.

[0058] Fig. 2 and Fig. 3 schematically show an exemplary carrier 30a with an effector 35, although not the entire length of the effector 35 is shown in Fig. 2. The carrier 30a has a flat and closed surface 32 on its upper side. On this surface 32 there is a holder 34 for the effector 35, which encloses the flat effector 35 at the edge at three points so that the effector 35 with its holder 38 for a workpiece to be treated can be subjected to its weight. The weight is statically absorbed by the carrier 30a and as a result the carrier 30a with the effector 35 and with the workpiece arranged on it in the holder 38 can be loaded or unloaded in a positionally stable manner, in particular without tilting or without wobbling or shaking. Furthermore, the effector 35 can be detached by pulling it out of the carrier 30a and, if necessary, replaced by another effector 35.The effector 35 is connected to the carrier 30a via the holder 34 in such a way that it projects laterally beyond the carrier 30a by several times its width, thereby placing the holder 38 for the workpiece at the free end of the effector 35 at a great distance from the carrier 30a. This means that even a slight inclination of the carrier 30a with the effector 35 leads to a significant vertical lowering or raising of the holder 38 for the workpiece, which is very advantageous for the process of transferring a workpiece to or from the carrier 30a.

[0059] The effector 35 is designed as a dimensionally stable plate made of light metal or carbon material and has a fork-shaped section 36 at its free end with two webs running parallel to one another which are connected to one another in a U-shape via a cross connection. Adjacent to the cross connection is a strip-shaped plate which is inserted into the receptacle 34 for the effector 35 on the carrier 30a and is releasably fixed. This ensures that a movement of the carrier 30a is transferred to the effector 35. This applies in particular to all lateral displacements in the X-direction or Y-direction as well as to a vertical displacement in the Z-direction and to all inclinations due to rotation about the Rx, Ry axes of rotation or rotation in the horizontal plane about the Rz axis of rotation.These movements can be carried out independently of one another or in combination by means of appropriate control by the control unit of the system for processing workpieces A, thus enabling conveying and transfer.

[0060] On the fork-shaped section 36, three receiving points 37 made of elastic material are arranged as elevations, which together define a plane running parallel to the effector 35. Together with the fork-shaped section 36, these receiving points form the receptacle 38 for a workpiece, two of which are arranged in the front end region of the legs and one of which is arranged in the central region of the cross connection of the fork-shaped section 36. This design of the receptacle 38 for a workpiece on the effector 35 has proven to be very robust and secure, and thus enables a very reliable and secure transfer of a workpiece as well as a very reliable and secure transport into or through system A.

[0061] The support 30, 30a is realized as a milled part made of aluminum, which has on its underside several webs 31, which form a supporting structure, which gives the support 30, 30a a very stiff and robust structure with low weight.

[0062] The webs 31 form two or more receiving spaces AR, into which the coupling units 20 designed as permanent magnets 21 are introduced and fixed. The fixing of the coupling units 20 in the receiving spaces AR is achieved by gluing using a vacuum-suitable adhesive 33, which is characterized by very low outgassing under the influence of a vacuum. The two receiving spaces AR with the coupling units 20 are arranged on the underside of the carrier 30 such that they face the coupling means 10 arranged outside the gas-tight casing 1 with the stainless steel or aluminum regions 2a, thereby ensuring a very efficient and reliable magnetic interaction for generating the levitation state and conveyance.In addition, several holes are provided in the webs 31 for attaching holders for guiding or holding specific workpieces. These holes are designed in such a way that, even after a fastening screw has been inserted into these holes, a continuous channel for venting remains, so that no unwanted gas can be stored in the hole. This design of the hole improves the quality and safety of the operation of system A, especially with regard to the quality of the controlled atmosphere, which has a vacuum.

[0063] Fig. 4a shows a schematic representation of the process of transferring a workpiece from a support to the carrier 30a with effector 35.

[0064] In an approach phase, the effector 35 with its holder 38, which is formed by the fork-shaped section 36, is moved beneath the workpiece to be treated and then raised until it first makes contact. The first contact of the holder 38 with the workpiece, which lies on the support and is to be transferred to the effector 35 so that the workpiece can be conveyed through the system A with the effector 35 and the carrier 30a, is detected using a measuring system 50 to determine the load on the effector 35. The approach phase begins in the immediate vicinity of the support and is preferably carried out exclusively by displacements without rotation or pivoting. This enables a very reliable approach until the first contact.

[0065] Subsequently, in a transfer phase, the orientation of the holder 38 of the effector 35 is pivoted such that, using the example of a holder 38 according to Figures 2 and 3, three points of contact are created between the holder 38 and the workpiece with the help of the three elevations, without any point of contact of the workpiece being lifted from the support. The pivoting is preferably carried out exclusively by rotational movements and thus without displacement movements. Here, too, a lifting of the workpiece is detected by the measuring system 50 by determining an abrupt increase in the load. As soon as such a selective, abrupt increase is determined, the pivoting is immediately adjusted and the lifting of the workpiece is thus prevented.This ensures that the holder 38 rests against the workpiece with three contact points, thus touching the workpiece without transmitting any relevant forces to the workpiece that could move it or change its shape. This ensures that the workpiece is not subjected to any unnecessary, particularly damaging, forces during this transfer phase, which could, in particular, bend or displace the workpiece. Damage to the workpiece is therefore largely ruled out.

[0066] The workpiece is then lifted in a vertical phase by vertical displacement and thus lifted off the support. This displacement preferably takes place without rotational movement, which ensures a very differentiated and safe vertical movement of the workpiece and thus secure reception of the workpiece in or on the holder 38 of the effector 35 of the carrier 30a and thus conveyance into or through the system A. During this phase, the load on the workpiece is very low because the workpiece rests in a statically defined manner on the several contact points, here three contact points, and in this way prevents damage to the workpiece, in particular due to unnecessary bending or slipping.

[0067] This enables a very efficient and reliable transfer from the support to the carrier 30a. Fig. 4b shows a schematic representation of the process of transferring a workpiece from the carrier 30a with the effector 35 to a support.

[0068] In an approach phase, the effector 35 with its holder 38 and the workpiece held therein is moved into the area above the support and then lowered until it first makes contact. The holder 38 is formed by the fork-shaped section 36. The first contact of the workpiece with the support, which lies on the holder 38 of the effector 35 and is to be transferred to the support, is detected using a measuring system 50 for determining the load on the effector 35 by detecting an abrupt decrease in the load. As soon as such a selective, abrupt decrease is detected, the vertical lowering is stopped immediately, thus preventing the workpiece from being lifted from the holder 38. The approach phase begins in the immediate vicinity above the support and is preferably carried out exclusively by vertical displacement without rotation or pivoting.This allows for a very reliable approach up to the first touch.

[0069] Subsequently, in a transfer phase, the orientation of the holder 38 of the effector 35 is pivoted such that several points of contact are created between the support and the workpiece, without any point of contact of the workpiece being lifted from the holder 38 by the support. The pivoting is preferably carried out exclusively by rotational movements and thus without displacement movements. Here, too, a lifting of the workpiece is detected with the aid of the measuring system 50 by identifying an abrupt decrease in the load. As soon as such a selective, abrupt decrease is identified, the pivoting is immediately adjusted and thus the lifting of the workpiece is prevented. This ensures that the holder 38 rests against the workpiece with three points of contact and thus touches the workpiece without transmitting relevant forces to the workpiece that could move the workpiece or change its shape.At the same time, the workpiece rests on the support with multiple contact points. This ensures that the workpiece is not subjected to any unnecessary, particularly damaging, forces during this transfer phase, which could, in particular, bend or displace the workpiece. Thus, damage to the workpiece is largely eliminated.

[0070] The workpiece is then lowered in a vertical phase by vertical displacement and thus placed on the support. This leads to a separation of the holder 38 from the workpiece, so that it is then possible to remove the carrier 30a with the effector 35 from the support by horizontal displacement. The vertical displacement preferably takes place without rotational movement, which ensures a very differentiated and safe vertical movement of the workpiece and thus a safe transfer of the workpiece from the holder 38 of the effector 35 of the carrier 30a to the support, for example for potential removal from system A. During this phase, the load on the workpiece is very low because the workpiece rests statically defined on the several contact points and in this way prevents damage to the workpiece, in particular due to unnecessary bending or slipping.

[0071] This enables a very efficient and safe transfer from the carrier 30a to the support. The system A shown in the figures enables extremely safe and gentle treatment of the workpiece during transfer from or to a carrier 30a, as well as during conveyance, and also during treatment in the treatment chamber B, since it is characterized by extremely good operational reliability, particularly with regard to the controlled atmosphere.

[0072] Reference symbol list

[0073] A system for the treatment of workpieces

[0074] AR receiving space for couplant

[0075] B Treatment room

[0076] Rx rotation axis in X direction

[0077] Ry rotation axis in Y direction

[0078] Rz rotation axis in Z direction

[0079] S Lock

[0080] SR lock room

[0081] SW lock wall

[0082] V Connection area

[0083] X X-direction

[0084] Y Y-direction

[0085] Z Z-direction

[0086] TO access opening

[0087] 1 gas-tight envelope

[0088] 2 floor

[0089] 2a Stainless steel or aluminum areas

[0090] 2b connecting piece

[0091] 4 Reinforcement

[0092] 5 common rigid frame

[0093] 6 Screw connection

[0094] 7 O-ring seal

[0095] 10 couplants

[0096] 11 electromagnetic stator

[0097] 20 coupling unit

[0098] 21 Permanent magnet carrier without effector a carrier with effector

[0099] Web of a supporting structure

[0100] Surface of the carrier vacuum-suitable adhesive

[0101] Recording on carrier 30a for effector

[0102] Effector

[0103] Fork-shaped section

[0104] Point of contact

[0105] Holder for workpiece

[0106] Shell section

Claims

Claims Carrier (30) for a system for treating workpieces (A), in particular wafers, wherein the system comprises a) a housing which defines a treatment chamber (B) in which a controlled atmosphere is present, and a gas-tight enclosure (1) which separates the controlled atmosphere from the atmosphere present outside the enclosure (1), b) a conveyor system through which workpieces can be conveyed in the treatment chamber (B), c) at least one coupling means (10) which is coupled to at least one coupling unit (20) of the conveyor system, wherein d) the gas-tight enclosure (1) is present between the coupling means(s) (10) and the coupling unit(s) (20), and these are coupled to one another without contact through the gas-tight enclosure (1), e) the coupling means(s) (10) are designed as electromagnetic stators (11) outside the gas-tight enclosure (1), f) the conveyor system has at least one carrier (30),g) workpieces can be conveyed into the treatment chamber (B) by means of the carrier (30), h) the carrier (30) has at least one permanent magnet (21) as a coupling unit (20), i) the carrier (30) can be held suspended in a contactless manner relative to the casing (1) and conveyed into the treatment chamber (B) by the interaction with the at least one coupling means (10) and the at least one coupling unit (20), characterized in that the carrier (30a) is provided with a receptacle (34) for an effector (35) and is connected to an effector (35) connected thereto, wherein the effector (35) projects laterally beyond the carrier (30) and is provided for laterally receiving the workpieces (A) to be treated. Carrier (30a) for a system for treating workpieces (A) according to claim 1, wherein the effector (35) projects beyond the carrier (30a) by at least the width of the carrier (30a).Carrier (30a) for a system for treating workpieces (A) according to one of claims 1 or 2, wherein the carrier (30a) with the effector (35) is designed to be movable in at least four degrees of freedom with the possibility of displacement in the three independent directions X, Y and Z directions and the possibility of rotational movement about at least one of the three independent axes of rotation Rx, Ry and Rz axes, in particular with the possibility of displacement in the three independent directions X, Y and Z directions. and the possibility of a rotational movement about all three independent axes of rotation Rx, Ry and Rz and thus movable in six degrees of freedom. Carrier (30a) for a system for treating workpieces (A) according to one of claims 1 to 3, wherein the effector (35) is flat with a maximum height of 4 cm, in particular in the range of 1 to 2 cm. Carrier (30a) for a system for treating workpieces (A) according to one of claims 1 to 4, wherein the effector (35) has a fork-shaped structure. Carrier (30a) for a system for treating workpieces (A) according to one of claims 1 to 5, wherein the effector (35) is detachable from the receptacle (38) on the carrier (30a). Carrier (30a) for a system for treating workpieces (A) according to one of claims 1 to 6, wherein the carrier (30a) with the effector (35) is provided with a measuring system (50) for determining the load on the effector (35) and / or the carrier (30a).Carrier (30a) for a system for treating workpieces (A) according to one of claims 1 to 7, wherein the effector (35) and the carrier (30a) are designed passively without an active drive. A carrier (30a) for a system for treating workpieces (A) according to one of claims 1 to 7, wherein the effector (35) is provided with a drive for changing its length, its orientation, and / or its holder (38) for the workpiece. A system for treating workpieces (A) with at least one carrier (30a) according to one of claims 1 to 9. A system for treating workpieces (A) according to claim 10, wherein the system has a further carrier (30) for conveying workpieces in the system (A), which is provided with a holder for the workpiece, which is provided for receiving the workpiece to be treated above the carrier (30a). A system for treating workpieces (A) according to claim 11, wherein a control is provided which enables a transfer of a workpiece from a carrier (30a) with an effector to the further carrier (30) without an effector, or vice versa.Method for transferring a workpiece to or from a carrier (30a) with effector (35) according to one of claims 1 to 9 or a system according to one of claims 10 to 12, wherein for a transfer to the carrier (30a) with effector (35) in an approach phase of the effector. (35) with its holder (38) is moved below the workpiece to be treated and is raised until the first contact, wherein the orientation of the holder (38) of the effector (35) is then adjusted by pivoting in a transfer phase so that several contact points are created, and wherein the workpiece is then lifted and lifted from the support by vertical displacement in a vertical phase, or wherein for a transfer from the carrier (30a) with effector (35), the effector (35) with its holder (38) and the workpiece are moved into the area of ​​the support in an approach phase and the workpiece is lowered until the first contact, wherein the orientation of the holder (38) of the effector (35) with the workpiece is then selected by pivoting in a transfer phase so that several contact points of the workpiece with the support are created,and wherein the workpiece is subsequently lowered in a vertical phase by vertical displacement and placed on the support. A method for transferring a workpiece according to claim 13, wherein the transfer phase is carried out exclusively by rotational movements of the effector (35) and / or the receptacle (38) of the effector (35). Method for transferring a workpiece according to one of claims 13 to 14, wherein the approach phase and / or the vertical phase occur exclusively by displacement of the effector (35) and / or the receptacle (38) of the effector (35). Method for transferring a workpiece according to one of claims 13 to 15, wherein, in the transfer phase, the effector (35) and / or the receptacle of the effector (35) is pivoted without a contact point of the workpiece being lifted by or from the storage device, and in particular, at least three contact points of the workpiece with the receptacle (38) of the effector (35) lie in a common plane.

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