Apparatus for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or for EUV lithography masks

Abstract

The present invention relates to an apparatus (10) for cleaning pot-shaped hollow bodies (12), in particular transport containers (30) for semiconductor wafers or for EUV lithography masks, wherein the apparatus (10) comprises: a support wall (20) onto which the hollow body (12) can be placed by way of its edge surface (38); a locking device (26) by means of which the hollow body (12) can be sealingly and releasably connected to the support wall (20); at least one passage opening (24) which is formed by the support wall (20) and is arranged radially within the locking device (26); a cleaning device (40) by means of which a first cleaning fluid can be dispensed for cleaning the hollow body inner surface (33) when the hollow body (12) is connected to the support wall (20); and a first discharge channel (70) with a first end (72), wherein the first discharge channel (70) with the first end (72) is in fluidic communication only with the passage opening (24) and with which the first cleaning fluid dispensed by the cleaning device (40) can be discharged.

Description

[0001] Device for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or for EUV lithography masks

[0002] The present invention relates to a device for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or for EUV lithography masks.

[0003] The production of highly integrated electronic circuits and other sensitive semiconductor components today takes place in factories where so-called semiconductor wafers undergo a multitude of processing steps. A large portion of these processing steps takes place in clean rooms, which are kept free of contaminants, especially particles, at great expense. Such complex processing is necessary because particles that come into contact with the semiconductor material of the semiconductor wafers can influence the material properties of the semiconductor wafers to such an extent that an entire production batch becomes defective and unusable, and must be rejected.

[0004] Since cleanliness becomes increasingly important with the increasing integration density of semiconductor circuits, and the effort required for cleanliness increases exponentially with the size of cleanrooms, semiconductor wafers are not transported "openly" from one processing station to the next. Instead, special transport containers (so-called FOUPs, Front Opening Unified Pods) are used. These are box-shaped transport containers into which a large number of semiconductor wafers are inserted. The FOUPs are usually closed with a removable lid. Without the lid, the FOUPs have a pot-shaped basic shape with a rectangular base. When the FOUPs are closed with their lids, the inserted semiconductor wafers can be transported from one cleanroom to another, protected from the environment.Once the FOUPs reach a processing station, they are opened, the semiconductor wafers are removed, and processed accordingly. After processing, the semiconductor wafers are transported back to the FOUPs and then forwarded to the next processing station.

[0005] Due to the high production downtime caused by contamination of semiconductor wafers, it is necessary to clean the FOUPs from time to time. The FOUPs are particularly contaminated by abrasion of the semiconductor wafers during insertion into and removal from the FOUPs.

[0006] The same applies to transport containers for EUV lithography masks ("extreme ultraviolet radiation"). EUV lithography masks are used to manufacture very small integrated circuits. Like semiconductors, EUV lithography masks also need to be transported, which creates a similar situation. When reference is made to FOUPs in the following, the relevant statements apply equally to transport containers for EUV lithography masks.

[0007] Devices for cleaning FOUPs are known for example from US 5238 703 A, WO 2005 / 001888 A2 and EP 1899 084

[0008] Bl known.

[0009] In such devices, the FOUPs are cleaned on both their inner and outer surfaces. Typically, the outer surfaces of the FOUPs are significantly more contaminated than the inner surfaces. As a result, the cleaning fluid becomes enriched during the cleaning process with particles from both the outer and inner surfaces. The particles can therefore be transported from the outer surface to the inner surface. However, a satisfactory cleaning result is only achieved when the number of particles falls below a certain value. Due to the particles originating from the outer surface, the cleaning process must be carried out for a sufficiently long period of time in order to remove a sufficient proportion of the particles.This is disadvantageous in that, on the one hand, the amount of cleaning fluid required is comparatively high, and, on the other hand, the FOUPs cannot be used to transport the semiconductor wafers during the cleaning process. This increases the cost of semiconductor wafer production. Furthermore, cleaning the outer surface only contributes to a limited extent to reducing defective semiconductor wafers.

[0010] The object of one embodiment of the present invention is to propose a device for cleaning pot-shaped hollow bodies, with which these can be cleaned using simple and cost-effective means within a short time.

[0011] This object is achieved with the features specified in claims 1. Advantageous embodiments are the subject of the subclaims.

[0012] One embodiment of the invention relates to a device for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or for EUV lithography masks, wherein the hollow body has - a bottom wall and one or more side walls which form an inner surface of the hollow body, and

[0013] - has an opening opposite the bottom wall, which is enclosed by an edge surface of the side wall, wherein the device

[0014] - a support wall on which the hollow body can be placed with the edge surface,

[0015] - a locking device with which the hollow body with the edge surface can be connected sealingly and detachably to the support wall,

[0016] - at least one through-opening formed by the support wall, which is arranged radially inside the locking device,

[0017] - a cleaning device with which a first cleaning fluid can be dispensed to clean the hollow body inner surface when the hollow body is connected to the support wall, and

[0018] - comprises a first discharge channel with a first end, wherein the first discharge channel with the first end is in fluid communication exclusively with the through-opening and with which the first cleaning fluid discharged by the cleaning device can be discharged.

[0019] For cleaning, the hollow body is placed with its edge surface on the support wall, with the opening in the hollow body and the through-opening in the support wall directly adjacent to one another. It is therefore possible to introduce the first cleaning fluid into the hollow body and thus clean the inner surface of the hollow body. Due to the fact that the locking device is designed such that the hollow body is not only fixed with the edge surface relative to the support wall, but is also sealed, the first cleaning fluid cannot leave the interior of the hollow body. Consequently, the first cleaning fluid cannot be contaminated by particles located outside the hollow body. The first cleaning fluid therefore serves exclusively to clean the inner surface of the hollow body, which, as mentioned at the beginning, is usually much less heavily contaminated than the outer surface of the hollow body.As a result, the first cleaning fluid is not contaminated with particles originating from the hollow body's outer surface, effectively cleaning the hollow body's inner surface. The edge surface represents the separating section between the hollow body's inner surface and the hollow body's outer surface when the hollow body is placed on the support wall. The edge surface also seals the hollow body against the support wall. The time required to clean the hollow body's inner surface can be significantly reduced compared to devices known from the prior art. In addition, the amount of first cleaning fluid required to clean the hollow body's inner surface is also reduced.

[0020] According to a further embodiment, the first discharge channel is connected to the support wall at its first end and encloses the through-opening. In this embodiment, the design effort required to provide the device can be kept to a minimum. In particular, the first discharge channel can either be manufactured integrally with the support wall or connected to it, for example, by welding.

[0021] In a further developed embodiment, the first discharge channel can widen in a funnel shape towards the first end. Due to the funnel-shaped widening of the first discharge channel towards the first end, differences in diameter between the through-opening and the first discharge channel can be easily compensated. This keeps the design effort to a minimum. Furthermore, there are no sudden jumps in diameter that could lead to flow disturbances, for example in the form of turbulence. These disturbances can lead to particle deposition, which can slow down or completely interrupt the removal of particles and adversely affect the cleaning of the hollow body's inner surface.

[0022] In a further developed embodiment, the first discharge channel can be flush with the through-opening at its first end. This eliminates dead spaces in which particles can accumulate, which could adversely affect the cleaning of the hollow body's interior surface.

[0023] In a further embodiment, the cleaning device can have a first cleaning head that protrudes beyond the through-opening. In this embodiment, the first cleaning head can be introduced into the interior of the hollow body. As a result, the distance between the first cleaning head and the hollow body's inner surface can be reduced. The pressure with which the cleaning fluid leaves the first cleaning head also acts on the hollow body's inner surface with only minimal loss, whereby the particles located on the hollow body's inner surface can be removed particularly effectively.

[0024] A further developed embodiment is characterized in that the first cleaning head is rotatably and / or translationally movable. Due to the mobility of the first cleaning head, it is possible to react to geometric peculiarities of the hollow body's inner surface. In particular, it is possible to apply the first cleaning fluid at least approximately perpendicularly to the hollow body's inner surface, whereby the kinetic energy of the first cleaning fluid can be used particularly effectively to clean the hollow body's inner surface.

[0025] According to a further developed embodiment, the first cleaning head has a number of first cleaning nozzles via which the first cleaning fluid can be dispensed at a spray angle, wherein the first cleaning head has an adjustment device with which the spray angle can be adjusted. The spray angle at which the first cleaning fluid is dispensed also determines the angle at which the cleaning fluid impinges on the hollow body's inner surface. An angle of 90° or approximately 90° is ideal. Due to the fact that the spray angle is adjustable, the geometry of the hollow body's inner surface can be simulated such that the first cleaning fluid can be applied to almost the entire hollow body's inner surface at an angle of 90° or approximately 90°.The hollow body's inner surface typically has angled sections, so that non-adjustable cleaning nozzles can cause shadowing, in which no or only a limited amount of the first cleaning fluid can be applied to the hollow body's inner surface with sufficient kinetic energy. Such shadowing can be avoided in this embodiment, thus improving the overall cleaning result.

[0026] A further developed embodiment can stipulate that the first cleaning nozzles can be opened and closed independently of one another. If one of the first cleaning nozzles is open, the first cleaning fluid can be dispensed, which is not possible when closed. It is thus possible to clean the inner surface of the hollow body in such a way that the expected cleaner sections are cleaned first and only then the more heavily contaminated sections. This makes it possible to keep the loading of the first cleaning fluid with particles released from the inner surface of the hollow body as low as possible for as long as possible. In particular, this prevents comparatively clean sections from being cleaned with the first cleaning fluid, which already has a high loading. In many cases, the absorption capacity of the first cleaning fluid for particles decreases with increasing loading.In extreme cases, particles from the first cleaning fluid may even deposit on a comparatively clean section of the hollow body's inner surface. This can be prevented by appropriately controlling the first cleaning nozzles.

[0027] In addition, only specific sections of the hollow body's inner surface can be cleaned, and the number of particles collected can be counted. This particle count can be repeated frequently enough to allow representative conclusions. This makes it possible to determine whether an above-average number of particles are deposited on the hollow body's inner surface during a particular semiconductor wafer manufacturing process. This allows conclusions to be drawn about specific defects or potential improvements in the manufacturing process.

[0028] One embodiment is characterized in that the device has at least one coupling unit for coupling sound waves into the first cleaning fluid. The sound waves can be designed in particular as ultrasonic waves or as megasonic waves. While ultrasonic waves, depending on the definition, have a frequency range of approximately 20 kHz to 500 kHz, megasonic waves have a frequency range of approximately 500 kHz to 3 MHz. In this case, it is advisable to completely wet the inner surface of the hollow body with the first cleaning fluid or to flood the entire space enclosed by the inner surface of the hollow body and to couple the sound waves into the first cleaning fluid. The first cleaning fluid then serves as a transmitter of the sound waves.Due to the fact that a certain amount of energy is introduced into the first cleaning fluid, the cleaning effect is increased, as particles adhering to the hollow body's inner surface can be removed particularly effectively. The energy input increases with the frequency of the coupled sound. The use of megasound offers the advantage that the energy can be directed very precisely close to the hollow body's inner surface to be cleaned, thus achieving excellent cleaning results.

[0029] In a further embodiment, at least some of the coupling units can be integrated into or interact with at least some of the first cleaning nozzles. In this case, the cleaning nozzles can be designed as so-called "megasonic nozzles," which make it possible to couple the sound waves into the first cleaning fluid emitted by the first cleaning nozzles. It is then not necessary to wet the entire hollow body inner surface with the first cleaning fluid, whereby the amount of required first cleaning fluid can be kept low. According to a further embodiment, the cleaning device has a supply channel for supplying the first cleaning fluid to the first cleaning head, wherein the first discharge channel and the supply channel are combined, at least in sections, to form a fluid guide unit. However, the supply channel and the discharge channel remain fluidically separated.The supply channel and the discharge channel can be designed as piping and / or hoses. Combining the first discharge channel and the supply channel into a fluid guide unit saves installation space and thus allows for a compact device design. Furthermore, manufacturing costs can be kept low because the number of components in the device can be reduced.

[0030] According to a further embodiment, a first channel is arranged in the support wall, through which a rinsing fluid can be guided to the edge surface. Nitrogen or compressed air, and particularly preferably extremely clean dried air, also referred to as XCDA, is used as the rinsing fluid. This prevents the first cleaning fluid from reaching the outer surface of the hollow body via the edge surface, where it can mix with a second cleaning fluid. Furthermore, it prevents the second cleaning fluid from reaching the inner surface of the hollow body via the edge surface, where it can mix with the first cleaning fluid. Contamination is thus prevented.

[0031] A further embodiment is characterized in that a particle measuring device for determining the particles contained in the first cleaning fluid is arranged in the first discharge channel. The particle measuring device can, for example, be designed such that the number of particles that pass through the particle measuring device at a given volume flow of the first cleaning fluid through the first discharge channel is determined. If the number of counted particles falls below a certain value, it can be assumed that the inner surface of the hollow body has been sufficiently cleaned. The particle measuring device ensures, on the one hand, that the inner surface of the hollow body has actually been sufficiently cleaned; on the other hand, in this case, the cleaning process can be aborted.In the devices known from the prior art, the cleaning process is carried out until it can be assumed with sufficient probability that the hollow bodies have been adequately cleaned. In most cases, for safety reasons, the cleaning process is carried out significantly longer than necessary. Because it is possible, according to the present embodiment, to abort the cleaning process as described, both the duration and the quantity of the first cleaning fluid are reduced, so that the cleaning process can be carried out significantly more effectively overall than in the prior art. In addition, the particle measuring device also enables documentation that a specific FOUP has actually been cleaned to a sufficient extent.

[0032] According to a further developed embodiment, the hollow body has a lid with an inner lid surface and an outer lid surface, with which the opening can be closed. A cleaning opening is arranged in the support wall or in a further wall section, which opening can be at least partially closed with a closure body. The closure body has a receiving unit for receiving the lid of the hollow body, and the cleaning device has a further first cleaning head, with which the first cleaning fluid can be applied to the inner lid surface for cleaning when the cleaning opening is closed by the closure body or the lid.

[0033] The embodiments of the device described so far relate to cleaning the inner surface of the hollow body. As mentioned, the FOUPs are closed with a removable lid. However, just as on the inner surface of the hollow body, particles can accumulate on the inner surface of the lid, which can have a negative impact on the production of the semiconductor wafers. In this embodiment, however, the device comprises an additional first cleaning head with which the inner surface of the lid can be cleaned. For this purpose, the same first cleaning fluid is used that is also used to clean the inner surface of the hollow body. However, a further cleaning fluid can also be used if necessary. The particles on the inner surface of the lid can thus also be removed.To prevent the uncontrolled escape of the first cleaning fluid from the cleaning opening, the cleaning opening must be sealed during the cleaning process. For this purpose, either the lid or the closure body interacts with the support wall or the further wall section in such a way that the cleaning opening is sealed. The cleaning opening can be arranged so that no particles from the environment of the hollow body can enter the first cleaning fluid during the cleaning process. In this case, it is advisable to discharge the first cleaning fluid via the first discharge channel. The receiving unit of the closure body interacts with the outer surface of the lid so that the inner surface of the lid is freely accessible, in particular for the first cleaning fluid.A further embodiment stipulates that the closure body is movably attached to the support wall or the further wall section between an open position in which the closure body releases the cleaning opening, and a closed position in which the closure body closes the cleaning opening. In this embodiment, the closure body can be particularly well integrated into the handling of the lid. In the open position, a gripper robot or the like can insert the lid into the receiving unit of the closure body. The receiving unit is equipped with fixing means with which the lid can be releasably attached to the closure body. After the gripper robot has placed the lid down and the lid is attached to the closure body, the closure body is moved into the closed position.In the closed position, the cleaning opening is sealed, allowing the cleaning process to begin on the inner surface of the lid. After the cleaning process is complete, the closure body is moved back to the open position, and the connection between the closure body and the lid is released, allowing the gripper robot to remove the lid from the receiving unit. It is recommended that the closure body be attached to the support wall or to the other wall section in a rotatable manner.

[0034] A further embodiment provides that the device can have a second channel through which a rinsing fluid can be fed to the lid. The lid of a transport container usually has a lid seal with which the lid can be sealed against the rest of the transport container. Nitrogen or compressed air, and particularly preferably extremely clean dried air, also referred to as XCDA, is used as the rinsing fluid. The rinsing fluid can be used to precisely limit the effective range of the first cleaning fluid with which the inner surface of the lid is cleaned. The limitation can be selected such that the first cleaning fluid cannot reach the lid seal.This prevents particles in the first cleaning fluid from adhering to the seal, detaching from the seal during operation of the transport container, and damaging a semiconductor wafer. When a gas is used, a turbulent flow is generated, which promotes active blowing or cleaning of the seal.

[0035] According to a further embodiment in which the bottom wall and the side wall form an outer surface of the hollow body, the cleaning device has a second cleaning head with which a second cleaning fluid can be discharged to clean the outer surface of the hollow body. The device has a second discharge channel with which the second cleaning fluid discharged by the second cleaning head can be discharged. As mentioned at the beginning, it is not absolutely necessary to also clean the outer surface of the hollow body. Nevertheless, this may be desirable, for example to keep the particle concentration in the clean rooms low. In this embodiment, cleaning of the outer surface of the hollow body is possible, with the second cleaning fluid being discharged separately from the first cleaning fluid.Mixing of the first cleaning fluid and the second cleaning fluid and a resulting increase in the particle concentration with the particles originating from the hollow body's outer surface is prevented, which is not possible with prior art devices. Consequently, even if both the hollow body's inner and outer surfaces are cleaned, particles originating from the hollow body's outer surface are prevented from reaching the hollow body's inner surface. Consequently, the cleaning process of the hollow body's inner surface is not negatively affected by the particles originating from the hollow body's outer surface.

[0036] Typically, the particle concentration on the inner surface of the hollow body is lower than on the outer surface. The separate removal of the first cleaning fluid and the second cleaning fluid allows the first cleaning fluid to be reused to clean the outer surface of the hollow body. The loading (or particle concentration) in the first cleaning fluid can be determined to decide whether the loading of the first cleaning fluid is low enough to clean the outer surface of the hollow body to the necessary extent. If this is possible, the amount of cleaning fluid and, consequently, the cleaning costs can be kept low.

[0037] In a further developed embodiment, the device can have a housing which, together with the support wall, encloses a process chamber, wherein the process chamber is accessible via a housing opening that can be closed with a cover. The hollow body can be introduced into the process chamber through the housing opening and removed again. In this embodiment, it is possible to guide the second cleaning fluid in a defined manner and prevent its uncontrolled distribution in the device.

[0038] In a further developed embodiment, the support wall can have a number of through-holes, wherein the through-holes are arranged radially outside the locking device and through which the second discharge channel is fluidically connected to the process chamber. Depending on the design of the hollow bodies, the through-holes can also be designed as through-slots. The second cleaning fluid can be removed from the process chamber in a controlled manner via the second discharge channel without the second cleaning fluid mixing with the first cleaning fluid.

[0039] A further developed embodiment is characterized by the second cleaning head being U-shaped and capable of rotational and / or translational movement within the process chamber. Due to the U-shaped design of the second cleaning head, the second cleaning fluid can be directed to both the bottom wall and the side walls. The mobility of the second cleaning head allows for flexible response to geometrical peculiarities of the outer surface of the hollow body to be cleaned.

[0040] According to a further embodiment, the first cleaning head, the further first cleaning head, and / or the second cleaning head have at least one drying nozzle and / or an infrared diode. In this embodiment, the proposed device can be used not only for cleaning, but also for the subsequent drying of the hollow body. To conclude the cleaning process, the supply of the first cleaning fluid or of the first and second cleaning fluids is stopped and instead a drying gas, for example air or nitrogen, is conveyed through the fluid guide unit, with which the hollow body is dried. For this purpose, the hollow body has a correspondingly designed connection, in particular a vacuum connection, via which a vacuum can be generated within the hollow body in order to suck the drying gas into the hollow body and subsequently remove it from there again.A pipe, also known as a snorkel, is connected to this port, which can be connected to a vacuum pump, for example. The position of the hollow body in the device remains unchanged. Depending on the design, both the inner and outer surfaces of the hollow body can be dried. In this case, there is no mixing of the drying gas used for the inner surface of the hollow body with the drying gas used for the outer surface of the hollow body.

[0041] Furthermore, it is possible to equip the second cleaning nozzles and the second cleaning head with the same features as the first cleaning nozzles and the first cleaning head and vice versa, if this is appropriate.

[0042] Alternatively or in addition, infrared diodes can be used. These have the advantage that the radiation emitted by infrared diodes lies in a narrow frequency range optimized for the cleaning fluid used. Any remaining cleaning fluid residues on the inner or outer surface of the hollow body are very effectively heated and thus removed.

[0043] One embodiment of the invention relates to the use of a device according to one of the preceding embodiments for cleaning transport containers for semiconductor wafers. The technical effects and advantages that can be achieved with the proposed use correspond to those discussed for the present device. In summary, it should be noted that the time required to clean the hollow body's inner surface

[0044] Compared to prior art devices, this can be significantly reduced. Furthermore, the amount of initial cleaning fluid required to clean the hollow body's interior surface is also reduced. These advantages are particularly important in the production of semiconductor wafers.

[0045] One embodiment of the present invention relates to a method for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or for EUV lithography masks, using a device according to one of the preceding embodiments, comprising the following steps:

[0046] - Placing the hollow body on the support wall with the edge surface,

[0047] - Sealing and detachable connection of the hollow body to the support wall by means of the locking device, wherein the hollow body is sealed at the edge surface relative to the support wall, o Dispensing a first cleaning fluid for cleaning the hollow body inner surface by means of the first cleaning head of the cleaning device, and discharging the first cleaning fluid by means of the first discharge channel, and / or o Dispensing a second cleaning fluid for cleaning the hollow body outer surface by means of the second cleaning head of the cleaning device, and discharging the second cleaning fluid by means of the second discharge channel.

[0048] The technical effects and advantages that can be achieved with the proposed method correspond to those discussed for the present device. In summary, it should be noted that the hollow body's inner surface and the hollow body's outer surface can be cleaned independently of each other. Contamination of the first cleaning fluid, which is used to clean the hollow body's inner surface, with particles removed from the hollow body's outer surface is excluded.

[0049] With the proposed method, it is also possible to clean either only the outer surface of the hollow body or only the inner surface, if desired. Furthermore, the outer surface of the hollow body can be cleaned for a shorter time than the inner surface. Furthermore, it is also possible to clean both the outer and inner surfaces of the hollow body simultaneously.

[0050] According to a further embodiment, the method may comprise the following steps:

[0051] - Moving the bolt body into the open position,

[0052] - Placing the lid onto the receiving unit of the closure body with the outer surface of the lid and releasably fastening the lid to the closure body,

[0053] - Moving the bolt body into the locking position, and

[0054] - Dispensing the first cleaning fluid to clean the inner surface of the lid with the additional first cleaning head.

[0055] The lid can be placed on the receiving unit using a gripper robot, for example. In the open position, the receiving unit is easily accessible, allowing the lid to be placed and removed quickly and easily without the gripper robot having to perform complicated movements. In the closed position, the first cleaning fluid is guided, preventing mixing with the second cleaning fluid for the reasons mentioned above. It should be noted that the proposed device can also be operated so that only the lid and not the hollow body is cleaned. In this case, the through-opening can be closed with a closure element.

[0056] Further training specifies that the procedure includes the following steps:

[0057] - Completely flooding the space defined by the hollow body inner surface with the first cleaning fluid, and

[0058] - Coupling sound waves into the first cleaning fluid by means of a coupling unit.

[0059] The sound waves can be coupled in the form of ultrasound or megasound, for example. This improves the cleaning result because it introduces energy into the first cleaning fluid, which serves to loosen the particles on the inner surface of the hollow body. The inner surface of the lid and the outer surface of the hollow body can be treated accordingly.

[0060] According to further training, the procedure includes the following steps:

[0061] - Coupling sound waves into the first cleaning fluid emitted by the first cleaning nozzle by means of a coupling unit, wherein the coupling unit is integrated into the first cleaning nozzle or interacts with it.

[0062] In this configuration, the sound waves can also be coupled in as ultrasound or megasound. The cleaning result is also improved in this configuration for the reasons mentioned above. However, since flooding of the space defined by the hollow body's inner surface is not necessary in this configuration, the required amount of the initial cleaning fluid can be kept correspondingly low. The inner surface of the lid and the outer surface of the hollow body can be treated accordingly.

[0063] An exemplary embodiment of the invention is explained in more detail below with reference to the accompanying drawings.

[0064] Figure 1 shows a basic sectional view through an embodiment of a device for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or for EUV lithography masks,

[0065] Figure 2 is a non-scale view of section A defined in Figure 1, and

[0066] Figure 3 is a non-scale representation of section B defined in Figure 1.

[0067] Figure 1 shows an exemplary embodiment of a proposed device 10 for cleaning pot-shaped hollow bodies 12 based on a basic sectional view. The device 10 has a housing 14 which forms a housing opening 16 which can be closed with a cover 18 which can be removed from the housing 14. Furthermore, a support wall 20 is arranged in the housing 14, so that a closed process chamber 22 is created in the housing 14. The process chamber 22 is delimited by the support wall 20, the housing 14 itself and the cover 18. The support wall 20 forms a through-opening 24, with a locking device 26 being arranged radially outside the through-opening 24. In the exemplary embodiment shown, two through-bores 28 are provided in the support wall 20 radially outside the locking device 26.

[0068] With the cover 18 removed, a hollow body 12, in particular a transport container 30 for semiconductor wafers, also referred to as FOUPs, or a transport container 30 for EUV lithography masks, can be introduced into the process chamber 22. The hollow body 12 has a bottom wall 32 and, in this case, four side walls 34, so that the cup-shaped hollow body 12 is essentially cuboid-shaped. However, it is entirely possible to provide the cup-shaped hollow body 12 with a different geometry, for example, a cylindrical one. The bottom wall 32 and the four side walls 34 form a hollow body inner surface 33 and a hollow body outer surface 35.

[0069] The hollow body 12 has an opening 36, which is arranged opposite the bottom wall 32 and which is enclosed by an edge surface 38 formed by the side walls. In the region of the edge surface 38, the hollow body 12 is designed like a flange in the illustrated embodiment. With this edge surface 38, the hollow body 12 can be placed on the support wall 20. The through-opening 24 of the support wall 20 and the opening 36 of the hollow body 12 are at least approximately the same size and have the same geometric shape in the illustrated embodiment.

[0070] Furthermore, the locking device 26 is designed such that the through-opening 24 is at least approximately aligned with the section of the hollow body inner surface 33 adjoining the through-opening 24. In Figure 2, the area A marked in Figure 1 is not shown to scale, whereby there is no exact correspondence. For reasons of illustration, the locking device 26 is not shown. From Figure 2 it can be seen that the support wall 20 comprises a support wall section 37 which forms a contact surface 39 which is in contact with the edge surface 38 of the transport container 30. The contact surface 39 of the support wall section 37 is completely covered by the edge surface 38. A first channel 41 is arranged in the support wall section 37, which opens into the contact surface 39 and with which a flushing fluid, for example air or nitrogen, can be guided to the edge surface 38.

[0071] Furthermore, the device 10 is equipped with a cleaning device 40 having a first cleaning head 42, which protrudes beyond the through-opening 24 and is thus arranged within the process chamber 22. When the hollow body 12 is connected to the support wall 20, the first cleaning head 42 is enclosed by the hollow body 12.

[0072] The housing 14 further comprises a wall section 44 in which a cleaning opening 46 is arranged. The wall section 44 is located on the side of the support wall 20 facing away from the locking device 26. The cleaning opening 46 can be at least partially closed with a closure body 48 which is fastened to the wall section 44 by a drive unit (not shown) such that it can rotate about a first axis of rotation D1. The closure body 48 can be moved between an open position, in which the closure body 48 releases the cleaning opening 46, and a closed position, in which the closure body 48 at least partially closes the cleaning opening 46. In Figure 1, the closure body 48 is in the closed position.

[0073] The closure body 48 has a receiving unit 50 with which a lid 52, with which the hollow body 12 can be closed, can be releasably fastened to the closure body 48. The lid 52 forms an inner lid surface 54 and an outer lid surface 56. The inner lid surface 54 is the side of the lid 52 that directly adjoins the hollow body inner surface 33 when the hollow body 12 is closed with the lid 52. In other words, the inner lid surface 54 in this case faces the bottom wall 32 of the hollow body 12.

[0074] In the illustrated embodiment, the receiving unit 50 is designed such that it interacts with the cover 52 only by means of the cover outer surface 56.

[0075] In Figure 3, the area B marked in Figure 1 is not shown to scale, and there is no exact correspondence. It can be seen that a housing seal 51 is arranged in the housing 14 adjacent to the cleaning opening 46 and enclosing it. When the closure body 48 is in the closed position, the cover 52 interacts with the housing seal 51. In this respect, the cleaning opening 46 is closed and sealed by means of the cover 52. The statement that the closure body 48 at least partially closes the cleaning opening 46 should be understood against this background. However, it is also conceivable that the closure body 48 interacts with the housing seal 51 and completely seals the cleaning opening 46.Furthermore, Figure 3 shows that the lid 52 has a lid seal 53, with which the transport container 30 can be sealed when the lid 52 is connected to the transport container 30. Furthermore, a channel element 55 is arranged on the housing 14, which, together with the housing 14, forms a second channel 57 through which a flushing fluid, for example, air or nitrogen, can be guided to the lid 52. The channel element 55 is designed such that it forms a gap 60 with the lid seal 53.

[0076] The cleaning device 40 is also equipped with a further first cleaning head 58, which is arranged in the vicinity of the closure body 48 when the latter is in the closed position.

[0077] The cleaning device 40 also comprises a second cleaning head 64, which is essentially U-shaped and is arranged at least partially in the process chamber 22. In contrast to the first cleaning head 42, however, the second cleaning head 64 is arranged outside the hollow body 12 when the hollow body 12 is connected to the support wall 20 as shown in Figure 1. The second cleaning head 64 is rotatable about a second axis of rotation D2, wherein the drive device used for this is not shown. Also not shown is an embodiment in which the second cleaning head 64 is movable not only in rotation but also in translation or only in translation. In the illustrated embodiment, the first cleaning head 42 is not movable, but it can also be designed to be movable in rotation and / or translation.

[0078] The device 10 is further provided with a fluid guide unit

[0079] 66, with which a first cleaning fluid can be guided to the first cleaning head 42 and to the further first cleaning head 58, and a second cleaning fluid can be guided to the second cleaning head 64. The fluid guide unit 66 has a first supply channel 68, with which the first cleaning fluid can be guided to the first cleaning head 42.

[0080] For reasons of illustration, a detailed illustration of a second supply channel for supplying the second cleaning fluid to the second cleaning head 64 has been omitted, but its design should be readily apparent to a person skilled in the art.

[0081] Furthermore, the fluid guide unit 66 comprises a first discharge channel 70, with which the first cleaning fluid discharged by the first cleaning head 42 and by the further first cleaning head 58 can be discharged from the process chamber 22. The first discharge channel 70 has a first end 72 that is in fluid communication with the through-opening 24. As can be seen from Figure 1, the first discharge channel 70 widens in a funnel shape toward the first end 72 and is connected to the support wall 20 in such a way that the first end 72 of the discharge channel is flush with the through-opening 24.

[0082] A first particle measuring device 741 is arranged in the first discharge channel 70, with which the particles located in the first cleaning fluid and originating from the hollow body inner surface 33 can be determined and, in particular, counted. In addition, a second particle measuring device 742 is arranged in the secondary channel 742, with which the particles located in the first cleaning fluid and originating from the lid inner surface 54 can be determined and, in particular, counted. In addition, the fluid guide unit 66 has a second discharge channel 76, which is essentially constructed in the same way as the first discharge channel 70, but is in fluid communication with the two through-bores 28. The first discharge channel 70 forms the radially inner wall of the second discharge channel 76, so that the fluid guide unit 66 can be designed to be very compact.Not shown is an embodiment in which a further particle measuring device 74 is arranged in the second discharge channel 76. It should be noted at this point that the fluid guide unit 66 is only shown in principle in Figure 1. Due to the large number of channels nested and arranged at different levels, the representation of the fluid guide unit 66 according to Figure 1 makes no claim to accuracy. However, a person skilled in the art will easily be able to derive at least a functional structure of the fluid guide unit 66 from Figure 1.

[0083] The device 10 is operated in the following manner: In the initial state, not shown here, the cover 18 is open and the second cleaning head 64 is rotated by 90° with respect to Figure 1, so that the U-shaped section of the second cleaning head 64s 64 is perpendicular to the plane of Figure 1. The closure body 48 is in the open position, in which the closure body 48 is aligned approximately horizontally with respect to Figure 1.

[0084] Using a handling device (not shown), for example a gripper robot, the lid 52 is separated from the hollow body 12 and placed on the receiving unit 50. The opened hollow body 12 is introduced into the process chamber 22 such that the hollow body 12 rests with its edge surface 38 on the support wall 20, as shown in Figure 1. The hollow body 12 is then locked with the locking device 26 so that it is connected to the support wall 20 and thus fixed in the process chamber 22. The locking device 26 is equipped with sealing means (not shown here) so that the hollow body 12 is sealed against the support wall 20. The cover 18 is now closed. In addition, the receiving unit 50 of the closure body 48 is activated so that the lid 52 is fixed to the closure body 48. The closure body 48 is rotated by 90° into the closed position, as shown in Figure 1.The cover 52 seals the cleaning opening 46.

[0085] A first cleaning fluid is then fed via the first supply channel 68 to the first cleaning head 42 and discharged through first cleaning nozzles 78 such that the hollow body inner surface 33 is cleaned with the first cleaning fluid. The further first cleaning head 58 has further first cleaning nozzles 80, with which the first cleaning fluid is applied to the lid inner surface 54, which is subsequently cleaned.

[0086] At the same time, a second cleaning fluid, which can correspond to the first cleaning fluid, is fed via the second feed channel (not shown here) to the second cleaning head 64, where the second cleaning fluid is dispensed through second cleaning nozzles 82 to clean the hollow body outer surface 35. The second cleaning head 64 can be rotated about the second axis of rotation D2. The first cleaning nozzles 78, the further first cleaning nozzles 80 and the second cleaning nozzles 82 can be designed such that the spray angle α at which the first cleaning fluid and the second cleaning fluid are dispensed can be adjusted. For this purpose, the first cleaning nozzles 78, the further first cleaning nozzles 80 and the second cleaning nozzles 82 can be mounted in a spherical head shape.Alternatively or cumulatively, in particular the first cleaning nozzles 78 can be arranged on a tubular body 83 rotatable about a third axis of rotation D3, whereby the spray angle α can be adjusted. In any case, the first cleaning head 58 comprises an adjusting device 85 with which the spray angle α can be adjusted. The further first cleaning nozzles 80 and the second cleaning nozzles 80 can be designed accordingly, wherein the spray angle α at which the first cleaning fluid is dispensed by the further first cleaning nozzles 80 is likewise adjusted by the adjusting device 85. The adjusting device 85 can also be designed such that the spray angle α of the second cleaning nozzles 80, which are located on the second cleaning head 64, can also be adjusted.This makes it possible for the first cleaning fluid and the second cleaning fluid to impinge vertically or almost vertically on the hollow body inner surface 33 and the lid inner surface or the hollow body outer surface 35.

[0087] Furthermore, the device 10 has at least one coupling unit 87 for coupling sound waves into the first cleaning fluid. The coupling unit 87 can also be designed such that the sound waves are also coupled into the second

[0088] Cleaning fluid can be coupled in. In the illustrated

[0089] In this embodiment, some of the coupling units 87 are integrated into at least some of the first cleaning nozzles 78 and are designed as so-called "megasonic nozzles." A megasound can be coupled into the first cleaning fluid emitted by the first cleaning nozzles 78. The same can be provided for the further first cleaning nozzles 80 and the second cleaning nozzles 82.

[0090] The first cleaning nozzles 78 can be opened and closed independently of one another. Consequently, it is possible to clean different sections of the hollow body inner surface 33 first and other sections later. For example, sections that are known to be less heavily soiled can be cleaned first, followed by more heavily soiled sections. The further first cleaning nozzles 80 and the second cleaning nozzles 82 can be configured accordingly, so that the first lid inner surface 54 and the hollow body outer surface 35 can be cleaned accordingly.

[0091] At the same time, a rinsing fluid is guided through the first channel 41 to the edge surface 38 and / or through the second channel 57 to the cover 52. This can be the same rinsing fluid, but it is also possible to guide a first rinsing fluid through the first channel 41 and a second rinsing fluid, different from the first rinsing fluid, through the second channel 57. The rinsing fluid, which is guided through the first channel 41 to the edge surface 38, ensures that neither the first cleaning fluid nor the second cleaning fluid can cross the edge surface. The rinsing fluid therefore creates a fluidic seal between the first cleaning fluid and the second cleaning fluid. This ensures that the first cleaning fluid and the second cleaning fluid cannot mix. Contamination of the first cleaning fluid with the second cleaning fluid, and vice versa, is prevented.

[0092] The first cleaning fluid, which has been discharged by the first cleaning head 42 and applied to the hollow body inner surface 33, is discharged via the first discharge channel 70. The same applies to the first cleaning fluid, which has been discharged by the further first cleaning head 58 and applied to the lid inner surface 54. To discharge the first cleaning fluid, which is used to clean the lid inner surface 54, the first discharge channel 70 has a secondary channel 84, which opens into the first discharge channel 70.

[0093] The flushing fluid, which is directed to the cover 52, flows through the gap 60 back into the secondary channel 84. The housing seal 51 prevents the flushing fluid from escaping into the environment. The flushing fluid prevents the first cleaning fluid, which is discharged by the additional first cleaning head 58 and applied to the inner surface 54 of the cover, from reaching the cover seal 53, to which particles in the first cleaning fluid could adhere.

[0094] The flushing fluid which is supplied to the edge surface 38 and / or to the cover 52 can be placed under a sufficiently high pressure.

[0095] The first cleaning fluid removes particles that were located on the hollow body inner surface 33 and the lid inner surface 54. The particles originating from the hollow body inner surface 33 are detected by the first particle measuring device 741, and the particles originating from the lid inner surface 54 are detected by the second particle measuring device. The first particle measuring device 741 and the second particle measuring device 742 can be configured such that the number of particles that pass through the particle measuring device 74 at a given volume flow within a specific time is determined. This allows us to determine whether the hollow body inner surface 33 and the lid inner surface 54 have been cleaned to the desired extent or not.For example, if the hollow body inner surface 33 is sufficiently clean, the cleaning process for the hollow body 12 can be aborted while the cleaning process for the lid inner surface 54 continues. Meanwhile, the hollow body 12 can be removed from the device by the gripper robot, thus saving time.

[0096] As mentioned, an additional particle measuring device 74 can be arranged in the second discharge channel 76. This additional particle measuring device can detect the particles originating from the hollow body's outer surface 35. This information can also be incorporated into the decision as to whether or not the cleaning process for the hollow body 12 can be aborted. If the loading of the first cleaning fluid with particles originating from the hollow body's inner surface 33 does not exceed a certain value, it can also be used to clean the hollow body's outer surface 35.

[0097] Not shown is an embodiment in which the particle measuring device 74 is arranged downstream of the confluence of the secondary channel 84 and the first discharge channel 70. In this case, it is not possible to distinguish whether the particles originate from the inner surface 54 of the lid or from the inner surface 33 of the hollow body. Nevertheless, the cleaning process can be aborted if the number of particles falls below a certain level.

[0098] The second cleaning fluid, which has been discharged by the second cleaning head 64 and applied to the hollow body outer surface 35, is discharged via the second discharge channel 76. Consequently, the first cleaning fluid and the second cleaning fluid are discharged separately from one another, so that particles originating from the hollow body outer surface 35 cannot enter the first cleaning fluid and thus reach the hollow body inner surface 33 or the lid inner surface 54.

[0099] In general, the cleaning of the hollow body inner surface 33 and the lid inner surface 54 is more important than the cleaning of the hollow body outer surface 35. If it is determined that the hollow body inner surface 33 and the lid inner surface 54 have been cleaned to the desired extent, the cleaning process can be discontinued regardless of the extent to which the hollow body outer surface 35 has been cleaned.

[0100] Now, a first drying gas and a second drying gas, for example air or nitrogen, can be fed via the first supply channel 68 and the second supply channel, respectively, in largely the same way as the first and second cleaning fluids to the first cleaning head 42, to the further first cleaning head 58, and to the second cleaning head 64. However, for this purpose, a negative pressure is generated in the hollow body 12 by connecting a pipe (not shown) to a negative pressure connection 94, which pipe can be connected to a vacuum pump (likewise not shown). As a result of the negative pressure, the first drying gas and / or the second drying gas is sucked into the hollow body 12 and then removed from the hollow body 12 again.The first cleaning head 42 has first drying nozzles 86, the further first cleaning head 58 has further first drying nozzles 88, and the second cleaning head has second drying nozzles 90, with which the first drying gas and the second drying gas can be released and applied to the hollow body inner surface 33, the lid inner surface 54, and the hollow body outer surface 35. The first drying gas and the second drying gas displace the first cleaning fluid and the second cleaning fluid from the device 10. Residues of the first and second cleaning fluid can also be blown away.

[0101] In addition, the first cleaning head 42, the further first cleaning head 58 and the second cleaning head each have infrared diodes 92 with which residues of the first and second cleaning fluid can be heated and evaporated, as a result of which they can be removed from the device 10 by the first and second drying gas.

[0102] After the drying process is complete, the cover 18 is opened and the closure body 48 is moved into the open position. The cleaned hollow body 12 is removed from the process chamber. The receiving unit 50 is deactivated, as a result of which the cover 52 can be removed from the closure body 48 and fed to the hollow body 12 to close it.

[0103] Now, another hollow body 12 to be cleaned can be treated in the device 10 in the manner described. List of reference symbols

[0104] 10 Device

[0105] 12 hollow bodies

[0106] 14 housings

[0107] 16 Housing opening

[0108] 18 Cover

[0109] 20 support wall

[0110] 22 Process room

[0111] 24 passage opening

[0112] 26 Locking device

[0113] 28 through hole

[0114] 30 transport containers

[0115] 32 floor wall

[0116] 33 Hollow body inner surface

[0117] 34 side wall

[0118] 35 Hollow body outer surface

[0119] 36 Opening

[0120] 38 edge area

[0121] 40 Cleaning device

[0122] 42 first cleaning head

[0123] 44 wall section

[0124] 46 Cleaning opening

[0125] 48 locking bodies

[0126] 50 recording unit

[0127] 52 lids

[0128] 54 Lid inner surface

[0129] 56 Lid outer surface

[0130] 58 additional first cleaning head 64 second cleaning head

[0131] 66 Fluid guide unit

[0132] 68 first feed channel

[0133] 70 first discharge channel

[0134] 72 first end

[0135] 74 Particle measuring device

[0136] 76 second discharge channel

[0137] 78 first cleaning nozzles

[0138] 80 additional first cleaning nozzles

[0139] 82 second cleaning nozzles

[0140] 83 pipe bodies

[0141] 84 side channel

[0142] 85 Adjustment device

[0143] 86 first drying nozzles

[0144] 87 Coupling unit

[0145] 88 additional first drying nozzles

[0146] 90 second drying nozzles

[0147] 92 infrared diodes

[0148] 94 Vacuum connection a Spray angle

[0149] Dl first axis of rotation

[0150] D2 second axis of rotation

Claims

Patent claims 1. Device (10) for cleaning pot-shaped hollow bodies (12), in particular transport containers (30) for semiconductor wafers or for EUV lithography masks, wherein the hollow body (12) - a bottom wall (32) and one or more side walls (34) forming an inner surface (33) of a hollow body, and - comprising an opening (36) opposite the bottom wall (32), which is enclosed by an edge surface (38) of the side wall (34), wherein the device (10) - a support wall (20) onto which the hollow body (12) with its edge surface (38) can be placed, - a locking device (26) with which the hollow body (12) can be connected to the edge surface (38) in a sealing and detachable manner to the support wall (20), - at least one through-opening (24) formed by the support wall (20), which is arranged radially within the locking device (26), - a cleaning device (40) with which a first cleaning fluid can be dispensed for cleaning the inner surface (33) of the hollow body when the hollow body (12) is connected to the support wall (20), and - comprises a first discharge channel (70) with a first end (72), wherein the first discharge channel (70) with the first end (72) is exclusively in fluid communication with the through-opening (24) and with which the first cleaning fluid discharged by the cleaning device (40) can be discharged.

2. Device (10) according to claim 1, characterized in that the first discharge channel (70) is connected at its first end (72) to the support wall (20) and encloses the through-opening (24).

3. Device (10) according to claim 1 or 2, characterized in that the first discharge channel (70) widens in a funnel shape towards its first end (72).

4. Device (10) according to any of the preceding claims, characterized in that the first discharge channel (70) is flush with the through-opening (24) at its first end (72).

5. Device (10) according to any of the preceding claims, characterized in that the cleaning device (40) has a first cleaning head (42) which projects beyond the through-opening (24).

6. Device (10) according to claim 5, characterized in that the first cleaning head (42) is rotatably and / or translationally movable. 7.Device according to claim 6, characterized in that the first cleaning head (42) has a number of first cleaning nozzles (78) through which the first cleaning fluid can be dispensed at a spray angle (α), wherein the first cleaning head (42) has an adjustment device (85) with which the spray angle (α) can be adjusted.

8. Device according to any one of the preceding claims. characterized in that the device (10) has at least one coupling unit (87) for coupling sound waves into the first cleaning fluid.

9. Device according to claim 8, characterized in that at least some of the coupling units (87) are integrated into or interact with at least some of the first cleaning nozzles (78).

10. Device (10) according to any one of the preceding claims, characterized in that the cleaning device (40) has a feed channel (68) for supplying the first cleaning fluid to the first cleaning head (42), wherein the first discharge channel (70) and the feed channel (68) are combined at least section by section to form a fluid guide unit (66).

11. Device (10) according to any one of the preceding claims, characterized in that a first channel (41) is arranged in the support wall (20) by which a rinsing fluid can be guided to the edge surface (38). 12.Device (10) according to one of the preceding claims, characterized in that a particle measuring device (74) for determining the particles contained in the first cleaning fluid is arranged in the first discharge channel (70).

13. Device (10) according to one of the preceding claims, wherein the hollow body (12) has a lid (52) with an inner lid surface (54) and an outer lid surface (56) with which the opening (36) can be closed, characterized in that. - a cleaning opening (46) is arranged in the support wall (20) or in a further wall section (44), which can be closed at least partially with a closure body (48), wherein the closure body (48) has a receiving unit (50) for receiving the lid (52) of the hollow body (12), and - the cleaning device (40) has a further first cleaning head (58) with which the first cleaning fluid can be applied to the inner surface (54) of the lid for cleaning when the cleaning opening (46) is closed by the closure body (48) or by the lid (52). 14.Device (10) according to claim 13, characterized in that the closure body (48) is movably attached to the support wall (20) or the further wall section (44) between an open position, in which the closure body (48) releases the cleaning opening (46), and a closed position, in which the closure body (48) or the lid (52) closes the cleaning opening (46).

15. Device (10) according to claim 13 or 14, characterized in that the device (10) has a second channel (57) through which a rinsing fluid can be guided to the lid (52).

16. Device (10) according to any of the preceding claims, wherein the bottom wall (32) and the side wall (34) form a hollow body outer surface (35), characterized in that. - the cleaning device (40) has a second cleaning head (64) with which a second cleaning fluid can be dispensed for cleaning the outer surface (35) of the hollow body, and - the device (10) has a second discharge channel (76) with which the second cleaning fluid dispensed by the second cleaning head (64) can be discharged.

17. Device (10) according to claim 16, characterized in that the device (10) has a housing (14) which, together with the support wall (20), encloses a process chamber (22), wherein the process chamber (22) is accessible via a housing opening (16) that can be closed with a cover (18). 18.Device (10) according to claim 17, characterized in that the support wall (20) has a number of through-holes (28), wherein the through-holes (28) are arranged radially outside the locking device (26) and with which the second discharge channel (76) is fluidically connected to the process chamber (22).

19. Device (10) according to any one of claims 16 to 18, characterized in that the second cleaning head (64) is U-shaped and is rotatably and / or translatively movable in the process chamber (22).

20. Device (10) according to claim 5, claim 13 or claim 16, characterized in that the first cleaning head (42), the further first cleaning head (58) and / or the second. Cleaning head (64) comprising at least one drying nozzle (86, 88, 90) and / or an infrared diode (92).

21. Method for cleaning cup-shaped hollow bodies (12), in particular transport containers (30) for semiconductor wafers or for EUV lithography masks with a device according to one of the preceding claims, comprising the following steps: - placing the hollow body (12) onto the support wall (20) with the edge surface (38), - sealingly and releasably connecting the hollow body (12) to the support wall (20) by means of the locking device (26), wherein the hollow body (12) is sealed at the edge surface against the support wall (20), - dispensing a first cleaning fluid for cleaning the inner surface (33) of the hollow body by means of the first cleaning head (42) of the cleaning device (40), and draining the first cleaning fluid by means of the first drain channel (70).and / or o dispensing a second cleaning fluid for cleaning the outer surface of the hollow body (35) by means of the second cleaning head (64) of the cleaning device (40), and draining the second cleaning fluid by means of the second drain channel (76).

22. Method according to claim 21, comprising the following steps: - moving the closure body (48) into the open position, - placing the lid (52) onto the receiving unit (50) of the closure body (48) with the lid outer surface (56) and releasably attaching the lid (52) to the closure body (48), Moving the locking body (48) into the closed position, and - Dispensing the first cleaning fluid to clean the inner surface of the lid (54) with the further first cleaning head (58).

23. A method according to claim 21 or 22, comprising the following steps: - Complete flooding of the space bounded by the inner surface of the hollow body (33) with the first cleaning fluid, and - Coupling of sound waves into the first cleaning fluid by means of a coupling unit (87).

24. A method according to claim 21 or 22, comprising the following steps: - Coupling of sound waves into the first cleaning fluid emitted by the first cleaning nozzle (78) by means of a coupling unit (87), wherein the coupling unit (87) is integrated into or interacts with the first cleaning nozzle (78).

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