Device and method for transferring modular functional units, as well as a particle beam microscope for receiving the transfer device

Abstract

The invention relates to a transfer system for transferring functional units within a vacuum region of a particle beam microscope, wherein the transfer system comprises a transfer unit and at least two functional units. The functional units are each configured to perform a specific function. The transfer system is designed such that a first functional unit can be arranged within the vacuum region of the particle beam microscope in a first position and in a second position, wherein the transfer unit is configured to transfer the first functional unit from the first position to the second position and vice versa, and wherein the first functional unit can be detachably coupled to the transfer unit.Furthermore, the transfer system is designed such that a second functional unit can be arranged in a third position and a fourth position within the vacuum region of the particle beam microscope, with the transfer unit being configured to transfer the second functional unit from the third position to the fourth position and vice versa, while the second functional unit can be detachably coupled to the transfer unit.

Description

In a particle beam microscope (for example, a scanning electron microscope (SEM), an ion microscope (FIB), or a combined FIB / SEM instrument (focused ion beam / scanning electron microscope)), various functional units are typically permanently installed in the sample chamber. A functional unit is an assembly capable of performing a specific function. For example, a detector is a functional unit designed to detect electrons and / or ions. Other examples of functional units include gas injection systems (for the controlled introduction of process gases) or micromanipulators, which can be used to hold and / or controllably move a microscopic sample under investigation in three-dimensional space. Since these functional units require a certain amount of space within the sample chamber, the number of functional units that can be used on a particle beam microscope is usually very limited. The sample chamber typically has only a small number of access points (so-called ports) where functional units can be arranged. Furthermore, vacuum conditions prevail in the sample chamber during operation of the particle beam microscope, meaning that the functional units and their mounting must meet specific requirements, and the functional units usually need to be permanently installed. Therefore, it is generally not possible for the user to exchange functional units depending on the current microscopic application. Such application-dependent exchange would be too time-consuming and can often only be carried out by specialist personnel. Therefore, it is desirable to propose a transfer system for transferring functional units and to design the functional units in such a way that they can be exchanged without complex mechanical modifications. It would be particularly advantageous if the exchange of functional units could take place without having to break the vacuum in the sample chamber. The following documents are considered relevant prior art: DE 10 2008 045 336 B4 (Dömer et al.) describes a processing system in which a sample can be processed with a laser beam and an electron beam or an ion beam. For this purpose, a sample can be transported back and forth between a first processing location and a second processing location by a transport device. The transport device remains coupled to a base of the positioning table at all times. EP 2 950 324 B1 (Albiez et al.) discloses a rail-guided positioning arm with which a differential pressure module can be positioned within the sample chamber in an operating position and a non-operating position. A disadvantage of this is that the differential pressure module is fixedly mounted to the positioning arm. US 2008 / 0014056 A1 (Miller) relates to a method and a sample transfer system for introducing a sample into a process chamber via a lock. DE 10 2022 133 028 A1 (Weiss) discloses a transport module for sample bodies, comprising a base body with an interior or transport space and a closure element for closing the transport space. US 2003 / 01803776 A1 (Tomimatsu et al) discloses a device for preparing samples, wherein the device comprises various devices for receiving and transferring the samples. Overview of the invention The object of the present invention is to propose a transfer system with which modular functional units within a particle beam microscope can be exchanged and held in specific positions. This problem is solved by a transfer system with the features of claim 1. Advantageous embodiments of the method are given by dependent claims 2 to 9. The present invention also relates to a method for transferring functional units according to claim 10 and a particle beam microscope comprising a transfer system according to claim 11. The core of the invention is a modular system of functional units in which the functional units can be reversibly arranged at different positions inside a particle beam microscope. For transferring the functional units from one position to another, the transfer system includes a suitably designed transfer unit to which the functional units can be detachably coupled and, in the coupled state, selectively moved. A functional unit is understood to be a component assembly designed to perform a specific function during the operation of a particle beam microscope, such as a sample holder whose function is to hold a microscopic sample. This means that a functional unit is capable of performing a defined task in sample analysis, imaging, or preparation within the particle beam microscope, and thus produces a specific effect during operation. The positions where a functional unit can be arranged can be configured, for example, as a working position and a parking position. At a working position, the function of a functional unit located there can be performed, whereas this is not the case at a parking position. A parking position is therefore a non-working position. These positions serve as mechanical interfaces through which the modularly designed functional units can be arranged within the particle beam microscope. However, it is also conceivable that the positions could additionally function as electrical interfaces to control the functional units and / or execute their respective functions. The positions where the functional units can be arranged can be on any object or surface located in the vacuum area of ​​a particle beam microscope, for example in the sample chamber, on the SEM column, on the movable sample stage, on a sample holder or even on the microscopic sample itself. The vacuum region is understood to be a three-dimensional space enclosed by a vacuum jacket, in which vacuum conditions prevail during operation. The vacuum region typically comprises the sample chamber of the particle beam microscope and, if applicable, an airlock chamber attached to the sample chamber. The functional units can each be detached from the transfer unit and moved to a different position. Conversely, a functional unit can be detached from a position and picked up by the transfer unit. Advantageously, this is achieved by providing receiving devices at the positions that are compatible with the functional units. The entirety of the mounting devices at the various positions forms a mounting system. It is particularly advantageous if the mounting devices of the mounting system and the functional units are modular, ensuring compatibility. For example, the mounting devices can be designed as identical dovetail joints, allowing different functional units to be interchanged in the various positions. Instead of a positive-locking connection, it is also conceivable that the mounting device and functional elements can be joined by a material-locking or friction-locking connection. Crucially, the connection must be reversible, meaning it can be disassembled. Furthermore, it is advantageous if the transfer system includes a function unit changer configured to provide multiple function units. This is advantageously achieved by keeping the function units ready in the parking positions within the function unit changer. Finally, it proved advantageous for the transfer unit to be movable to a rest position, so that it can be positioned there whenever it is not needed for transferring functional units. This ensures that other processes during the operation of the particle beam microscope cannot be disrupted by the transfer unit. The functional units can, for example, be designed as active functional units. An active functional unit is understood to be a component that physically intervenes in the operating process, for example as a heating element, manipulator, detector (for detecting interaction particles and / or interaction radiation), gas injection system, or power supply. The functional units can also be designed as passive units that do not intervene in the operational process, such as a temperature sensor. Furthermore, it is particularly advantageous if the functional units are designed in such a way that several functional units can be interconnected. The functional units can be essentially identical or different. The functional units can, for example, be designed as micromanipulators. Micromanipulators are used, for instance, in nanoprobing. However, the functional units can also be designed differently, for example as apertures, detectors, sensors, sample holders, or sample holder modules that can be assembled into a multi-part sample holder. The functional units are generally designed for use in the vacuum environment of the particle beam microscope. Therefore, it can be advantageous if the particle beam microscope optionally features an airlock and / or a transfer shuttle, which further simplifies the handling of different functional units. A transfer shuttle is a compact, detachable, transportable airlock that can be flanged to a particle beam microscope during use (i.e., when loaded with an object). In a particularly advantageous embodiment, the transfer shuttle is designed as an inert shuttle. In this case, the object chamber of the inert shuttle contains a protective gas atmosphere, so that an object placed in the object chamber can be transported under protective gas and transferred into the vacuum region of the particle beam microscope. Examples of implementation Exemplary embodiments of the invention are explained below with reference to the figures. For an explanation of the components, reference is therefore also made to the entire preceding and subsequent descriptions. Fig. 1 shows a first embodiment of the transfer system according to the invention, in which the functional units are designed as micromanipulators. Fig. 2 shows a second embodiment, in which the functional units are designed as sample holders and sensors. Fig. 3 shows a variant of the second embodiment, which differs from the embodiment of Fig. 2 in the design of the electrical connection. Fig. 4 shows a third embodiment, with which pressure-stage apertures on the objective of a particle beam column can be changed. Fig. 5 shows a further embodiment in which several functional units are provided in a functional unit changer.Furthermore, the functional units are stackable in the working position, i.e., they can be reversibly (i.e., detachably) coupled to one another. Fig. 6 shows another embodiment of the invention, which is similar to the embodiment of Figs. 2 and 3, and in which two sample holders are transferred, which interact in the working position. Fig. 7 illustrates another embodiment with a multi-part sample holder comprising two modules. Figs. 7(a) to 7(i) illustrate the insertion and transfer of a first sample holder module, while Figs. 7(j) to 7(r) show the insertion and transfer of a second sample holder module and the joining of the two sample holder modules. Fig. 8 is a schematic flowchart of the method according to the invention. Fig. 9 shows a FIB / SEM combination instrument as an example of a particle beam microscope with which the method according to the invention can be carried out. Fig. 1 shows a first exemplary embodiment of the transfer system according to the invention. In this application example, the aim is to arrange several micromanipulators 4, 5 on a sample holder 2 inside a sample chamber 1 in order to enable special sample processing such as nanoprobing. The present invention provides a transfer system in the sample chamber 1 of a particle beam microscope, comprising a movable transfer unit 6. It has proven advantageous if the transfer unit 6 has an elongated transfer rod 7 that passes through a vacuum seal 11 provided in the wall 10 of the sample chamber, as schematically indicated in Fig. 1. A portion of the transfer unit 6 is always arranged and configured within the vacuum chamber 12 of the particle beam microscope to reversibly accommodate a functional unit. The transfer system further comprises at least two functional units, in this case two micromanipulators 4, 5, which are provided within the sample chamber 1 (i.e., in the vacuum region). The micromanipulators 4, 5 can each be arranged in a first position 14, 16, the parking position, and a second position 15, 17, the working position. A micromanipulator 4, 5 is held in the parking position when not in use, whereas it is held in the working position when used for sample handling, i.e., when performing its function. Fig. 1a shows how the first micromanipulator 4 and the second micromanipulator 5 are held in their respective park positions 14 and 16 by an optional changing device in the form of a functional unit changer 8. The micromanipulators 4, 5 can be detachably coupled to the transfer unit 6. Each coupled micromanipulator 4, 5 can then be moved from its parked position to a working position by moving the transfer unit 6, as shown in Fig. 1b. In the working position, the respective micromanipulator 4, 5 can be reversibly positioned on the sample holder 2 to perform its function in handling the sample 3. For example, the micromanipulator 4, 5 can pick up and hold the sample 3. To perform this function, the respective micromanipulator 4, 5 is transferred from the transfer unit 6 to the working position on the sample holder 2. Both micromanipulators 4, 5 can therefore be transferred from a parking position to a working position using the transfer unit 6. In the case of the second micromanipulator 5, it may be advantageous in the present example to rearrange the sample holder 2 relative to the transfer unit 6 in order to make the working position 17 of the second micromanipulator 5 accessible for transfer. For this purpose, the sample stage 13 together with the sample holder 2 can, for example, be rotated about a rotational axis R (as described for the particle beam microscope of Fig. 9), as indicated by the arrow in Fig. 1c. This allows the working position 17 of the second micromanipulator 5 to be arranged in a way that makes it accessible to the transfer unit 6 (Fig. 1d), so that the transfer unit can reversibly transfer the second micromanipulator 5 to this working position 17. Once the micromanipulators 4, 5 have been arranged in their working positions 15, 17 to perform their function, the transfer unit 6 can advantageously be retracted into a rest position, as shown in Fig. 1e. It is thus conceivable that the transfer unit can be positioned near the chamber wall 10, so that further sample handling or processing is not disturbed by the transfer unit. After completion of the work with the micromanipulators, both micromanipulators can be transferred from their working positions to the transfer unit, as they are detachably connected. The micromanipulators can then be moved back to their respective parking positions 14 and 16 and placed back into their parking positions. In principle, it has proven particularly advantageous if the transfer system comprises a receiving system having several receiving devices 14', 15', 16', 17'. Advantageously, the receiving system is designed such that all parking positions and all working positions are each provided with a receiving device 14', 15', 16', 17' for the reversible receiving of a functional unit. The mounting devices 14', 15', 16', 17' can, for example, be designed as a positive-locking connection, such as dovetail joints or bayonet fittings. However, it is also conceivable that the mounting devices 14', 15', 16', 17' are designed differently, for example as threaded holes, magnetic holders, or adhesive holders. It is also conceivable that the connection is friction-fit or material-fit. The essential point here is that the functional units can each be detachably connected to the mounting devices 14', 15', 16', 17'. This means that the functional units are designed as modules that are compatible with the transfer unit and the receiving devices and can be picked up reversibly. This enables flexible transfer and positioning of the functional units. Therefore, the receiving system of the transfer system of Fig. 1 is configured such that the first micromanipulator 4 can be received in the first park position 14 by a first receiving device 14', and in the first working position 15 by a second receiving device 15'. Furthermore, the receiving system is configured to receive the second micromanipulator 5 in the second parking position 16 from a third receiving device 16' and in the second working position 17 from an associated fourth receiving device 17'. The transfer unit and the micromanipulators are configured such that the micromanipulators can be transferred from the respective receiving device to the transfer unit and vice versa. Furthermore, the transfer system can include a functional unit changer 8, which can provide several micromanipulators in their respective parking positions. Advantageously, the functional unit changer 8 is arranged in the vacuum region 12, i.e., inside the sample chamber 1. Advantageously, the receiving devices associated with the parking positions (in the present example: the first receiving device 14' and the third receiving device 16') are integrated into the functional unit changer 8. It has proven particularly advantageous if the functional unit changer 8, with the micromanipulators it contains, can be introduced into the vacuum chamber 12 by means of an optional airlock 9 located on the sample chamber 1, without breaking the vacuum. Similarly, it is conceivable to introduce the sample holder 2, along with the sample 3, into the sample chamber 1 via the airlock 9. In principle, the micromanipulators 4 and 5 can each be individually transferred by the transfer unit 6 in the manner described. However, it is also conceivable that both micromanipulators 4 and 5 could be simultaneously detachably coupled to the transfer unit 6, transferred, and then released again. Furthermore, a transfer system 6 is conceivable that comprises not just one transfer unit, but several transfer units. Fig. 2 shows a second embodiment of the transfer system, in which the functional units are configured as a sample holder 26 and a sensor 22. The sample holder 26 is designed to hold a sample to be examined (not shown). The sensor 22 can, for example, be configured as a temperature sensor to monitor the temperature of the sample during microscopic examination. It has proven particularly advantageous for the particle beam microscope to include an airlock 23. The airlock 23 is usually flanged to a port of the sample chamber 28. Controllable airlock valves 24 allow the airlock chamber to be connected to or separated from the volume of the sample chamber 28. To introduce (or remove) objects or components into the sample chamber 28 via the airlock 23, the airlock 23 typically has a movable airlock rod 25. It has proven advantageous if the sample holder 26 can be coupled to the lock rod 25 and, after insertion, can be transferred from the lock rod 25 to the transfer unit 20. In principle, it is advantageous if the functional units (i.e., sensor 22 and sample holder 26) can each be arranged in a park position during work breaks, as shown in Fig. 2a. In the present specific example, the sensor 22 is held in the park position by the transfer unit 20. The transfer unit 20 of the transfer system includes a transfer rod 21 to which the functional units can be detachably coupled. To prepare for microscopic examination, the sample holder 26 can be inserted into the vacuum region of the sample chamber 28 via the lock 23 using the lock rod 25 through the open lock valves 24 (Fig. 2b) without breaking the vacuum. The sample holder 26 can then be detachably coupled to the transfer rod 21 of the transfer unit 20 (Fig. 2c), so that both functional units 22, 26 can be transferred to their working position on the sample table 27 by the process of the transfer unit 20, as shown in Fig. 2d. As described above, receiving devices can be provided at the parking positions and the working positions, which serve as modular interfaces. In order not to disturb further investigations or operating states of the particle beam microscope, the transfer unit 20 can be withdrawn from the sample chamber and held in a rest position, as shown in Fig. 2e. To operate the sensor 22, it can be connected to a controller 29 via a direct cable connection 30 in order to control or read the sensor. In the example shown in Fig. 2, the cable connection 30 is located on the sensor 22 itself. In an alternative embodiment of the second design, shown in Fig. 3, the electrical control of the sensor 22 is configured such that an alternative cable connection 31 is arranged on the sample stage 27, i.e., near the working position of the sensor 22. The interface on the sample stage 27 can provide all necessary electrical connections, e.g., power supply and signal line. In a particularly advantageous embodiment shown in Fig. 3, the electrical interface is integrated into the receiving device 32 in the working position. As soon as the sensor 22 has been transferred to the receiving device 32, the sensor 22 can be controlled by the controller 29. Fig. 4 shows a third embodiment that enables improved changing of pressure-stage apertures on the objective of a particle beam column of a particle beam microscope. In this embodiment, the functional units are designed, among other things, as pressure-stage apertures. Typically, the objective lenses of particle beam microscopes are shaped like a truncated cone, with the cone enclosing the optical axis. Often, additional components, such as a cap or a pressure-graduated diaphragm, are arranged adjacent to the top surface of the truncated cone. Pressure-graduated diaphragms serve to separate different pressure zones within a particle beam microscope while simultaneously ensuring the optical path of the beam. The objective 40 of the particle beam column 46 shown in Fig. 4 is at least partially located in the sample chamber 41 of the particle beam microscope, which is maintained under vacuum conditions during operation. Depending on the desired sample application, it is necessary to arrange a pressure-stage diaphragm, adapted to the sample application, at the end of the objective (i.e., at the top surface of the frustoconical objective) to ensure that the vacuum region is divided into different pressure zones. For example, in normal mode, a first pressure-level aperture 43 with a relatively large aperture is used, while when switching to variable-pressure mode (VP mode), a second pressure-level aperture 44 with a smaller aperture diameter is used. Since the aperture of the second aperture 44 has a smaller diameter, the achievable image field is somewhat restricted, but the smaller aperture is necessary to prevent a pressure increase inside the particle beam column 46. The transfer system according to the invention facilitates the changing of such pressure stage orifices 43, 44. The transfer system comprises a transfer unit 45 and at least two pressure stage orifices 43, 44, which generally have different orifice diameters. Advantageously, the pressure-stage orifices 43, 44 are kept in a parked position within the sample chamber or within the vacuum region. This can be accomplished by means of an exchange device in the form of an orifice changer 42 (Fig. 4a). Furthermore, the pressure stage orifices 43, 44 can be arranged in a working position (Figs. 4c to 4e), with the transfer unit 45 carrying out the transfer between the two positions as described above. To enable the transfer, the transfer unit 45 is designed such that the pressure stage orifices 43, 44 can be detachably coupled to the transfer unit 45. The transfer system according to the invention therefore comprises a transfer unit configured to transfer the pressure stage orifice from a first position to a second position, and from the second position to the first position. In other words, the transfer unit is designed to move the pressure stage orifice from the parked position to the working position, where it can perform its function. Conversely, the transfer unit is also designed to move the pressure stage orifice back from the working position to the parked position, where it can be stored. As already described above, in the embodiment of Fig. 4, receiving devices can also be provided at the parking and working positions, which enable the modular use of the pressure stage orifices 43, 44. Furthermore, it is conceivable that not only identical functional units are transferred, such as the described pressure-stage diaphragms 43, 44, which differ only in the diameter of their aperture openings. It is also conceivable that the transfer unit can transfer different functional units, such as a pressure-stage diaphragm and a detector 47, to the working position on the lens 40 (Fig. 4e). The detector 47 could, for example, be a BSD detector (backscattered electron detector), which is usually arranged on the lens 40. Due to the modular design of the functional units and the receiving devices, it is therefore possible to arrange another, different type of functional unit (i.e., a functional unit that is set up to perform a different function) using the transfer system instead of or in addition to a pressure-stage diaphragm, so that the functional units can perform their respective function in the particle beam microscope. Furthermore, it is conceivable that several identical or several different functional units are connected to each other at the working position, i.e., stacked on top of each other, as explained in more detail for Fig. 5 and Fig. 6. In another embodiment, shown in Fig. 5, several functional units 53, 55, 57, 58 (e.g. micromanipulators and detectors) are provided in parking positions in a functional unit changer 52. A first functional unit 53 can be transferred from the parking position to a working position by means of the transfer unit 51 and delivered to the working position, as shown in Fig. 5a. The working position can, for example, be arranged on a sample holder 54. The transfer unit 51 is controlled by the controller 56. Then a second functional unit 55 can be moved from the park position to the working position (Fig. 5b). Since the first functional unit 53 has a receiving device, the second functional unit 55 can be reversibly coupled to the first functional unit 53. This means that two functional units can be mounted on top of each other in the working position, but can also be detached from each other again. This is particularly advantageous when there is little space available on the sample holder or in the sample chamber in general. Furthermore, it is conceivable that the particle beam microscope may optionally have a lock 59 and / or an inert shuttle 60 (for introducing objects under a protective gas atmosphere) (as shown in Fig. 5), which further facilitates the handling of various functional units. Fig. 6 shows a further embodiment of the invention, which is designed similarly to the embodiment of Fig. 2 and Fig. 3, and in which two sample holders 61, 62 can be coupled to each other, so that both sample holders 61, 62 can interact with each other. This embodiment is advantageous, for example, for preparing a TEM lamella from a sample block. For instance, the first sample holder 61 can hold the sample block during processing with the focused ion beam (FIB), allowing a TEM lamella to be prepared and removed from the sample block. The second sample holder 62 can then provide a special device to receive the removed, very fragile TEM lamella after lift-out. However, the sample holder combination required for this procedure is often so large that it cannot be introduced into the airlock chamber 69 or the sample chamber 68 of the particle beam microscope via an airlock. With the invention proposed here, it is possible to introduce the sample holders 61 and 62 separately into the vacuum chamber and then arrange them in such a way that both sample holders 61 and 62 can perform their respective functions and cooperate during TEM lamella preparation. For example, the first sample holder 61, together with the sample block, can be inserted into the lock chamber 69 via the inert shuttle 64 with the inert shuttle valve 65 open. The second sample holder 62 is advantageously kept in a parking position inside the lock chamber (Fig. 6a). Using the transfer unit 63, both sample holders 61, 62 can be transferred into the sample chamber 68 via the open lock valve 66. There, the sample holders 61, 62 can be transferred to the adjacent working positions on the sample table 67 (Fig. 6b). The adjacent sample holders 61, 62 can then work together during sample preparation. Fig. 6c shows an example of how two sample holders 610, 620 can be separably connected to each other by a simple mechanism. In this specific example, the first sample holder 610 is a sample holder with a special sample receptacle and the second sample holder 620 is a sample holder with a standard sample receptacle. The transfer rod 630 of the transfer unit 63 is connected to the first sample holder 610. The first sample holder 610 is then moved closer to the second sample holder 620 by moving the transfer rod 630 and connected to it. The transfer rod 630 is then detached from the sample holders and returned to its resting position. The idea of ​​a multi-part, or modularly designed, sample holder is further developed in the embodiment of the invention shown in Fig. 7. It is conceivable that a sample holder is formed from two separable modules that can be used with the aid of the transfer system according to the invention. This has the advantage that the sample holder can be disassembled into smaller assemblies that can easily be introduced into the vacuum region of a particle beam microscope via an inert shuttle, which would not be possible without disassembly due to the size. Fig. 7 shows how the two sample holder modules 74, 75 are introduced into the vacuum area and assembled into a ready-to-use configuration using the transfer unit. First, a first sample holder module 74 of the modular sample holder is provided in an inert shuttle 73 (Fig. 7a). Using the inert shuttle 73, it is possible to provide the first sample holder module 74, which advantageously holds the sample (not shown), under a protective gas atmosphere. The inert shuttle 73, thus loaded, is arranged on a flange on the lock chamber 81 (Fig. 7b). The shuttle valve 82 is opened, allowing the first sample holder module 74 to be introduced into the vacuum chamber by means of a shuttle rod 76 (Fig. 7c). Meanwhile, the transfer unit 84 is in its rest position, so that the insertion of the first sample holder module 74 can proceed undisturbed. Then the first sample holder module 74 is detachably coupled to the transfer rod 77 of the transfer unit 84 (Fig. 7d). The first sample holder module 74 is then temporarily moved into an intermediate position by moving the transfer unit 84 (Fig. 7e). Holding it in the intermediate position releases the inert shuttle. The now unloaded inert shuttle 73 is removed from lock chamber 81 to clear the way for further operations (Fig. 7f). The first sample holder module 74 is then inserted into the sample chamber 71 via the now open lock valve 83 by means of the transfer rod 77 of the transfer unit 84, and positioned in the working position on the sample table 79 (Fig. 7g). Advantageously, this is done by transferring the sample holder module 74 to a corresponding receiving device on the sample table 78. The transfer rod 77 is then moved back to its rest position. The shuttle valve 82 is closed (Fig. 7h). The inert shuttle 73 is removed from the lock chamber 81 and is ready to receive the next object for entry (Fig. 7i). Then the inert shuttle 73 is loaded with the second sample holder module 75 ( Fig. 7j). The inert shuttle 73 is again arranged on the flange at the lock chamber 81 ( Fig. 7k). Then the shuttle valve 82 is opened to introduce the second sample holder module 75 into the lock chamber 81 by means of the shuttle rod 76 (Fig. 7l ). In the following step, the second sample holder module 75 is detachably coupled to the transfer rod 77 of the transfer unit 84 (Fig. 7m) and then moved into the park position by moving the transfer unit 84 (Fig. 7n). The inert shuttle 73 is then removed from the lock 72 (Fig. 7o). Finally, the second sample holder module 75 is moved into the working position on the sample table 79 by means of the transfer rod 77 (Fig. 7p). Advantageously, it is detachably coupled there to the first sample holder module 74. The transfer unit 84 is then moved into the rest position (Fig. 7q) and the inert shuttle 73 is removed from the lock chamber 81 (Fig. 7r). The two sample holder modules 74, 75 are now arranged in their working position, so that sample processing can begin. To remove the two sample holder modules 74, 75 from their working positions, it is advantageous to proceed in reverse order. The present invention further comprises a method (Fig. 8) for transferring functional units in the vacuum region of a particle beam microscope. The method is carried out with a transfer system comprising a transfer unit and at least one first and one second functional unit, as described above. The functional units can be designed, for example, as micromanipulators (as described for Fig. 1) or sample holders or sensors (as described for Fig. 2 and Fig. 3) or as pressure-stage orifices. The transfer system is designed such that the first functional unit can be arranged in a first parking position and a first working position within the vacuum region of the particle beam microscope. Furthermore, the transfer system is designed such that the second functional unit can be arranged in a second parking position and a second working position within the vacuum region of the particle beam microscope. In a first step S1, the functional units (e.g., micromanipulators) are positioned in their respective parking positions. It is particularly advantageous if this is done using a functional unit changer. In the next step S2, the first functional unit is detachably coupled to the transfer unit. In step S3, the first functional unit is transferred from the first parking position to the first working position by moving the transfer unit. In principle, the working positions can be located anywhere in the vacuum region of the particle beam microscope, for example on any objects, assemblies or surfaces such as the wall of the sample chamber, the SEM column, the sample holder or the sample stage. The first functional unit is detached from the transfer unit and transferred to the first working position (S4). Then (step S5) the second functional unit is detachably coupled to the transfer unit in an analogous manner. In step S6, the second functional unit is transferred from the second parking position to the second working position by moving the transfer unit. Then the second functional unit is detached from the transfer unit and transferred to the second working position (S7). Further functional units can be transferred as required or advantageous for the desired microscopic application. Finally, the functions of the functional units are executed (step S8). In the present example of micromanipulators, the microscopic sample is held or moved. Fig. 9 schematically shows a FIB / SEM combination device 90, which is a particle beam microscope that can include the transfer system according to the invention and can thus be used to carry out the method according to the invention. For this purpose, the FIB / SEM combination device 90 has a transfer system comprising a transfer unit 112 and several functional units 114, which can be configured, for example, as micromanipulators, detectors, or sensors. Advantageously, the transfer system also includes a functional unit changer 115, which allows for the straightforward provision of several functional units 114. It is particularly advantageous if the transfer system has receiving devices, wherein these receiving devices and the functional units are modularly designed so that they are compatible with one another and can be reversibly (i.e., detachably) connected to one another. A microscopic sample 105 can be provided on a sample holder 104, which is mounted on a sample stage 103. The sample stage 103 is located inside the sample chamber 99 of the FIB / SEM combination instrument 90. During operation, vacuum conditions are maintained inside the sample chamber 99. Advantageously, the sample stage 103 is designed as a multi-axis stage, thus providing several translational and rotational axes. An example of such a sample stage is a five-axis stage comprising the translational axes x, y, and z, as well as the rotational axes R and T (tilting). The translational axes are arranged perpendicular to each other. Typically, the rotational axis R runs parallel to the z-axis, while the tilting axis T is perpendicular to the rotational axis R. The FIB / SEM combination instrument 90 comprises two particle beam columns: an electron beam column 91 for generating an electron beam and an ion beam column 111 for generating an ion beam. Both particle beams are directed towards the microscopic sample 105, which is usually located at the point of coincidence of the two particle beams. During operation of the FIB / SEM combination instrument 90, electrons are generated in an electron source 92. The primary electrons propagate along the optical axis 94 of the electron column 91, are focused by condenser systems 93, 95, parallelized and clipped by at least one aperture 96. Furthermore, the electron beam column 91 includes a first deflection system 97, which enables the scanning of the primary electron beam across the surface of the sample, and an objective lens system 98. Using the objective lens system 98, the primary beam can be focused onto the microscopic sample 105. Furthermore, the FIB / SEM combination instrument 90 comprises an ion beam column 111 with an ion source 109, a second deflection system 107, a second aperture 113, a lens system (FIB) 106 and an objective lens system (FIB) 110. The ion source 109 can, for example, be a liquid metal ion source (LMIS), such as a gallium ion source. The ions generated in the ion source 109 are accelerated along the optical axis 108 of the ion beam column 111. The ion beam is then bundled and focused onto the sample 105 using the objective lens system 110. Using the ions striking the microscopic sample 105, material can be removed from the sample 105 and / or the sample 105 can be imaged. Optionally, the FIB / SEM combination instrument 90 can include a gas injection system 102 for supplying process gas to the sample chamber 99. The process gas can enable accelerated removal of sample material or the deposition of material onto the sample surface. Furthermore, the FIB / SEM combination instrument 90 includes at least one detector 100 for detecting interaction products of the interaction of electrons and / or ions and the material of the microscopic sample 105. The detector 100 can, for example, be a SE detector or a BSE detector for detecting secondary electrons (SE) or backscattered electrons (BSE). The detector can also be configured as a detector that detects interaction radiation, such as an EDX detector. The FIB / SEM combination instrument 90 also includes an evaluation and control unit 101. The evaluation and control unit 101 can receive and read a computer program. The computer program comprises a sequence of control commands which, when executed, cause the particle beam microscope (e.g., the FIB / SEM combination instrument 90) to perform the method according to the invention. Optionally, the FIB / REM combination instrument 90 can also include a lock (not shown) and / or an inert shuttle (not shown) through which objects or assemblies can be introduced into the vacuum region of the particle beam microscope. The inventive method and transfer system can be used not only in a FIB / SEM combination instrument. Rather, the particle beam microscope used can also be configured differently, for example as an electron beam microscope in which an electron beam is generated, or an ion beam microscope in which a beam of ions is generated. Reference symbol list 1 Sample chamber 2 Sample holder 3 Sample 4 First micromanipulator 5 Second micromanipulator 6 Transfer unit 7 Transfer rod 8 Function unit changer 9 Airlock (optional) 10 Wall 11 Vacuum seal 12 Vacuum area 13 Sample stage 14 First acquisition position (first parking position) 15 Second acquisition position (first working position) 16 Third acquisition position (second parking position) 17 Fourth acquisition position (second working position) 14' First acquisition device 15' Second acquisition device 16' Third acquisition device 17' Fourth acquisition device 20 Transfer unit 21 Transfer rod 22 Sensor 23 Airlock 24 Airlock valve 25 Airlock rod 26 Sample holder 27 Sample stage 28 Sample chamber 29 Controller 30 Cable connection 31 Alternative cable connection 32 Acquisition device 40 Lens 41 Sample chamber 42 Aperture changer (Function unit changer) 43 First pressure stage orifice 44 Second pressure stage orifice 45 Transfer unit 46 Particle beam column 47 Detector 51 Transfer unit 52Functional unit changer 53 First functional unit 54 Sample holder 55 Second functional unit 56 Controller 57 Third functional unit 58 Fourth functional unit 59 Airlock (optional) 60 Inert shuttle 61 First sample holder 62 Second sample holder 63 Transfer unit 64 Inert shuttle 65 Shuttle valve 66 Airlock valve 67 Sample stage 68 Sample chamber 69 Airlock 610 First sample holder (with special sample holder) 620 Second sample holder (with standard sample holder) 630 Transfer rod 71 Sample chamber 72 Airlock 73 Inert shuttle 74 First sample holder module 75 Second sample holder module 76 Shuttle rod 77 Transfer rod 78 Holder mount on sample stage 79 Sample stage 81 Airlock chamber 82 Shuttle valve 83 Airlock valve 84 Transfer unit 90 FIB / SEM combination instrument 91 Electron beam column 92 Electron source 93 First condenser system 94 Optical axis of the electron beam column 95 Second condenser system 96 Aperture 97 First deflection system 98 Objective lens system (SEM) 99 Sample chamber100 Detector 101 Evaluation and control unit 102 Gas injection system 103 Sample stage 104 Sample holder 105 Microscopic sample 106 Lens system (FIB) 107 Second deflection system 108 Optical axis of the ion beam column 109 Ion source 110 Objective lens system (FIB) 111 Ion beam column 112 Transfer unit 113 Second aperture 114 Functional unit (e.g., micromanipulator) 115 Functional unit changer X x-axis Y y-axis Z z-axis R Rotation axis T Tilt axis S1 Step: Provide functional units S2 Step: Detachably couple the first functional unit to the transfer unit S3 Step: Transfer the first functional unit to the first working position S4 Step: Transfer the first functional unit to the first working position S5 Step: Detachably couple the second functional unit to the transfer unit S6 Step: Transfer the second functional unit to the second working position S7 Step: Second Transfer functional unit to second work position S8 Step: Execute functions of the functional units

Claims

Transfer system for transferring functional units (4, 5, 43, 44, 53, 55, 57, 58, 61, 62, 74, 75, 114) in a vacuum region of a particle beam microscope (90), wherein the transfer system comprises a transfer unit (6, 20, 51, 63, 84, 112) and at least two functional units (4, 5, 43, 44, 53, 55, 57, 58, 61, 62, 74, 75, 114), wherein the functional units (4, 5, 43, 44, 53, 55, 57, 58, 61, 62, 74, 75, 114) are each configured to perform a function during the operation of the particle beam microscope (90); and wherein the transfer system is configured such that that a first functional unit (4, 26) can be arranged within the vacuum region of the particle beam microscope (90) in a first position (14) and in a second position (15);and the transfer unit (6, 20, 51, 63, 84, 112) is configured to transfer the first functional unit (4, 26, 43) from the first position (14) to the second position (15) and vice versa, wherein the first functional unit (4, 26, 43) is detachably connectable to the transfer unit (6, 20, 51, 63, 84, 112); and furthermore, the transfer system is configured such that a second functional unit (5, 22, 47) can be arranged within the vacuum region of the particle beam microscope (90) in a third position (16) and in a fourth position (17); and the transfer unit (6, 20, 51, 63, 84, 112) is further configured to transfer the second functional unit (5, 22, 47) from the third position (16) to the fourth position (17). and vice versa, wherein the second functional unit (5, 22, 47) can be detachably coupled to the transfer unit (6, 20, 51, 63, 84, 112). Transfer system according to claim 1, wherein the first (14) and the third position (16) are configured as parking positions, while the second (15) and the fourth position (17) are configured as working positions. Transfer system according to claim 1 or 2, wherein the transfer system comprises a receiving system, and the receiving system is configured such that the first functional unit (4) in the first position (14) can be received by a first receiving device (14'), and the first functional unit (4) in the second position (15) can be received by a second receiving device (15'); and furthermore, the second functional unit in (5) the third position (16) can be received by a third receiving device (16'), and the second functional unit (5) in the fourth position (17) can be received by a fourth receiving device (17'); and wherein the transfer unit (6) and the functional units (4, 5) are configured such that the functional units (4, 5) can be transferred from the respective receiving device (14', 15', 16', 17') to the transfer unit (6) and from the transfer unit (6) to the respective receiving device (14', 15', 16', 17'). 16', 17'). Transfer system according to one of claims 1 to 3, wherein the receiving devices of the receiving system are designed in a similar manner, so that different, modularly designed functional units can be transferred with the transfer system. Transfer system according to one of claims 1 to 4, wherein the first functional unit (4) and the second functional unit (5) are essentially identical. Transfer system according to one of claims 1 to 4, wherein the first functional unit (43, 44) and the second functional unit (47) are designed differently. Transfer system according to one of the preceding claims, wherein functional units can be reversibly coupled to one another. Transfer system according to one of the preceding claims, wherein the transfer system further comprises a function unit changer (8, 42, 52, 115) which is configured to hold several function units in such a way that they are transferable with the transfer system. Transfer system according to one of the preceding claims, wherein the functional units are designed as one of the following embodiments: aperture (43, 44), micromanipulator (4, 5), detector (47), sensor (22), sample holder (26), sample holder module (61, 62, 74, 75) of a multi-part sample holder. A method for transferring functional units in a vacuum region of a particle beam microscope by means of a transfer system, wherein the transfer system comprises a transfer unit and at least two functional units, and the functional units are each configured to perform a function; and wherein the transfer system is configured such that a first functional unit can be arranged within the vacuum region of the particle beam microscope in a first parking position and a first working position; and furthermore, the transfer system is configured such that a second functional unit can be arranged within the vacuum region of the particle beam microscope in a second parking position and a second working position; and wherein the method comprises the steps: - providing the functional units in the vacuum region in the respective parking position (S1); - detachably coupling the first functional unit to the transfer unit (S2);- Transferring the first functional unit from the first parking position to the first working position using the transfer unit (S3); - Transferring the first functional unit from the transfer unit to the first working position (S4); - Detachably coupling the second functional unit to the transfer unit (S5); - Transferring the second functional unit from the second parking position to the second working position using the transfer unit (S6); - Transferring the second functional unit from the transfer unit to the second working position (S7); - Executing the function of the functional units (S8).; Particle beam microscope (90), comprising a sample stage (103) for receiving a sample holder (104), wherein the sample holder (104) is configured to hold a microscopic sample; a particle beam source (92, 109) for generating a particle beam that can be directed onto a microscopic sample held by the sample holder; a sample chamber (99) enclosing a vacuum region within the particle beam microscope (90); and a transfer system for transferring functional units in the vacuum region of the particle beam microscope, wherein the transfer system comprises a transfer unit (112) and at least two functional units (114), each functional unit (114) being configured to perform a function; and wherein the transfer system is configured such that a first functional unit (114) can be arranged in a first position and in a second position within the vacuum region of the particle beam microscope (90);and the transfer unit (112) is configured to transfer the first functional unit (114) from the first position to the second position and vice versa, wherein the first functional unit (114) can be detachably coupled to the transfer unit (112); and furthermore, the transfer system is configured such that a second functional unit can be arranged in a third position and a fourth position within the vacuum region of the particle beam microscope; and the transfer unit is further configured to transfer the second functional unit from the third position to the fourth position and vice versa, wherein the second functional unit can be detachably coupled to the transfer unit.

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