DE202020006006U1 - Device for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or for EUV lithography masks - Google Patents

Abstract

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 a hollow body inner surface (33), and
- has 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) on which the hollow body (12) can be placed with the edge surface (38),
- a locking device (26) with which the hollow body (12) with the edge surface (38) can be connected to the support wall (20) in a sealing and detachable manner,
- at least one through opening (24) formed by the support wall (20) and arranged radially inside the locking device (26),
- a cleaning device (40) with 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
- comprises a first discharge channel (70) with a first end (72), wherein the first discharge channel (70) with the first end (72) is in fluid communication exclusively with the through opening (24) and with which the first cleaning fluid discharged by the cleaning device (40) can be discharged.

Description

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.

The production of highly integrated electronic circuits and other sensitive semiconductor components is now carried out in factories in which so-called semiconductor wafers undergo a large number of processing steps. A large part of these processing steps takes place in clean rooms, which are kept free of contamination, 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 in such a way that an entire production batch becomes faulty and unusable and has to be discarded.

Since keeping the semiconductor circuits clean becomes more and more important as the integration density of the semiconductor circuits increases and the effort required to keep them clean increases exponentially as the size of the clean rooms increases, the semiconductor wafers are not transported "open" from one processing station to the next. Instead, special transport containers are used (so-called FOUPs, Front Opening Unified Pods). 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 clean room to another, protected from the environment. When the FOUPs have reached 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 moved to the next processing station.

Due to the high production downtime caused by contamination of the semiconductor wafers, it is necessary to clean the FOUPs from time to time. The FOUPs are contaminated in particular by the abrasion of the semiconductor wafers when they are placed in and removed from the FOUPs.

The same applies to transport containers for EUV lithography masks (extreme ultra-violet radiation). EUV lithography masks are used to produce very small integrated circuits. Like semiconductors, EUV lithography masks also have to be transported, which creates a similar situation. When we refer to FOUPs below, the relevant statements apply equally to transport containers for EUV lithography masks.

Devices for cleaning FOUPs are, for example, from the US 5 238 703 A , the WO 2005/001888 A 2 and the EP 1 899 084 B1 known.

In such devices, the FOUPs are cleaned on both their inner and outer surfaces. The FOUPs are usually significantly more contaminated on their outer surface than on their inner surface. As a result, the cleaning fluid becomes enriched with particles from both the outer surface and the inner surface during the cleaning process. The particles can therefore be transported from the outer surface to the inner surface. However, a satisfactory cleaning result is only achieved if the number of particles has fallen below a certain value. Due to the particles originating from the outer surface, the cleaning process must be carried out for a correspondingly long period of time in order to be able 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 makes the production of semiconductor wafers more expensive. In addition, cleaning the outer surface only contributes to a limited extent to reducing defective semiconductor wafers.

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 within a short time using simple and cost-effective means.

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

• - eine Bodenwand und eine oder mehrere Seitenwände, die eine Hohlkörperinnenfläche bilden, und
• - eine der Bodenwand gegenüberliegende Öffnung aufweist, die von einer Randfläche der Seitenwand umschlossen wird, umfasst, wobei die Vorrichtung
• - eine Auflagewand, auf welche der Hohlkörper mit der Randfläche aufgelegt werden kann,
• - eine Verriegelungseinrichtung, mit welcher der Hohlkörper mit der Randfläche dichtend und lösbar mit der Auflagewand verbindbar ist,
• - zumindest eine von der Auflagewand gebildete Durchgangsöffnung, die radial innerhalb der Verriegelungseinrichtung angeordnet ist,
• - eine Reinigungseinrichtung, mit welcher ein erstes Reinigungsfluid zum Reinigen der Hohlkörperinnenfläche abgegeben werden kann, wenn der Hohlkörper mit der Auflagewand verbunden ist, und
• - einen ersten Abführkanal mit einem ersten Ende umfasst, wobei der erste Abführkanal mit dem ersten Ende ausschließlich mit der Durchgangsöffnung in Fluidkommunikation steht und mit welchem das von der Reinigungseinrichtung abgegebene erste Reinigungsfluid abgeführt werden kann.

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

• - a bottom wall and one or more side walls forming a hollow body inner surface, and
• - has an opening opposite the bottom wall, which is enclosed by an edge surface of the side wall, wherein the device
• - a support wall on which the hollow body can be placed with the edge surface,
• - a locking device with which the hollow body with the edge surface can be connected to the support wall in a sealing and detachable manner,
• - at least one through-opening formed by the support wall, which is arranged radially inside the locking device,
• - a cleaning device with which a first cleaning fluid can be dispensed for cleaning the hollow body inner surface when the hollow body is connected to the support wall, and
• - 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.

For cleaning, the hollow body is placed with its edge surface on the support wall, with the opening of the hollow body and the through-opening of the support wall directly adjacent to one another. It is therefore possible to introduce the first cleaning fluid into the hollow body and thus to clean the inner surface of the hollow body. Due to the fact that the locking device is designed in such a way 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 is therefore used exclusively to clean the inner surface of the hollow body, which, as mentioned at the beginning, is usually significantly less contaminated than the outer surface of the hollow body. As a result, the first cleaning fluid is not contaminated with particles originating from the outer surface of the hollow body, whereby the inner surface of the hollow body is effectively cleaned. The edge surface represents the separating section between the hollow body inner surface and the hollow body outer surface when the hollow body is placed on the support wall. The hollow body is also sealed against the support wall at the edge surface. The time required to clean the hollow body inner surface can be significantly reduced compared to devices known from the prior art. In addition, the amount of the first cleaning fluid required to clean the hollow body inner surface is also reduced.

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 low. In particular, the first discharge channel can either be manufactured integrally with the support wall or connected to it, for example by welding.

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. In addition, 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 accumulation, which can slow down or completely interrupt the removal of particles and adversely affect the cleaning of the hollow body's inner surface.

In a further developed embodiment, the first discharge channel can be flush with the through-opening at the first end. There are no dead spaces in which particles can accumulate, which can have a negative impact on the cleaning of the hollow body's inner surface.

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 inner surface can be reduced. The pressure with which the cleaning fluid leaves the first cleaning head also acts on the hollow body inner surface with only a small loss, whereby the particles located on the hollow body inner surface can be removed particularly effectively.

A further developed embodiment is characterized in that the first cleaning head is rotatably and/or translatorily movable. Due to the mobility of the first cleaning head, it is possible to react to geometrical peculiarities of the hollow body inner surface. In particular, it is possible to direct the first cleaning fluid at least approximately perpendicular to the inner surface of the hollow body, whereby the kinetic energy of the first cleaning fluid can be used particularly effectively for cleaning the inner surface of the hollow body.

According to a further embodiment, the cleaning device has a feed channel for feeding the first cleaning fluid to the first cleaning head, wherein the first discharge channel and the feed channel are combined at least in sections to form a fluid guide unit. However, the feed channel and the discharge channel remain fluidically separated. The feed channel and the discharge channel can be designed as piping and/or as hoses. Due to the combination of the first discharge channel and the feed channel to form a fluid guide unit, installation space can be saved and the device can thus be designed compactly. In addition, the manufacturing effort can be kept low because the number of components of the device can be reduced.

According to a further embodiment, a first channel is arranged in the support wall, with which a flushing 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 flushing 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. It also 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.

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 in such a way 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 cleaned to a sufficient extent, and on the other hand the cleaning process can be aborted in this case. 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 sufficiently cleaned. In most cases, for safety reasons, the cleaning process is carried out for 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 amount 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.

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. In this case, a cleaning opening is arranged in the support wall or in a further wall section, which can be at least partially closed with a closure body, wherein 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.

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 like on the inner surface of the hollow body, particles can accumulate on the inner surface of the lid, which can have a negative influence on the production of the semiconductor wafers. In this embodiment, however, the device comprises a further first cleaning head with which the inner surface of the lid can be cleaned. The same first cleaning fluid is used for this purpose that is also used to clean the inner surface of the hollow body. However, a further cleaning fluid can also be used if this appears necessary. The particles on the inner surface of the lid can thus also be removed. In order 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 interact 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 in such a way that no particles can enter the cleaning process during the cleaning process. Particles from the environment of the hollow body can get into the first cleaning fluid. It is advisable to discharge the first cleaning fluid via the first discharge channel. The receiving unit of the closure body works together with the outer surface of the lid so that the inner surface of the lid is accessible without obstruction, in particular for the first cleaning fluid.

Another embodiment specifies 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 gripping 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 detachably attached to the closure body. After the gripping robot has put the lid down and the lid is attached to the closure body, the closure body is moved to the closed position. In the closed position, the cleaning opening is sealed so that the cleaning process can be started with regard to the inner surface of the lid. After the cleaning process has ended, the closure body is moved back to the open position and the connection between the closure body and the lid is released so that the gripping robot can remove the lid from the receiving unit. It is advisable to attach the closure body rotatably to the support wall or the further wall section.

A further embodiment provides that the device can have a second channel with which a flushing 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 from the rest of the transport container. Nitrogen or compressed air, and particularly preferably extremely clean dried air, also referred to as XCDA, are used as the flushing fluid. The flushing fluid can be used to precisely limit the area of effect of the first cleaning fluid with which the inner surface of the lid is cleaned. The limitation can be selected so 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. If a gas is used, a turbulent flow is generated, which promotes active blowing or cleaning of the seal.

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 can be desirable in order to keep the particle concentration in the clean rooms low, for example. 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 outer surface of the hollow body is prevented, which is not possible with the devices from the prior art. Consequently, even if both the inner surface and the outer surface of the hollow body are cleaned, particles originating from the outer surface of the hollow body are prevented from reaching the inner surface of the hollow body. The cleaning process of the inner surface of the hollow body is therefore not negatively influenced by the particles originating from the outer surface of the hollow body.

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 to avoid its uncontrolled distribution in the device.

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 with 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.

A further developed embodiment is characterized in that the second cleaning head is U-shaped and can be moved in a rotational and/or translational manner in the process space. Due to the U-shaped design of the second cleaning head, the second cleaning fluid can be guided to both the bottom wall and the side walls. Due to the mobility of the second cleaning head, it is possible to react flexibly to geometric peculiarities of the hollow body outer surface to be cleaned.

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 subsequently drying the hollow body. To complete the cleaning process, the supply of the first cleaning fluid or 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. The position of the hollow body in the device remains unchanged. Depending on the design, both the inner surface of the hollow body and the outer surface 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.

Furthermore, it is also 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.

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

One embodiment of the invention relates to the use of a device according to one of the previous embodiments for cleaning transport containers for semiconductor wafers. The technical effects and advantages that can be achieved with the proposed use correspond to those that have been discussed for the present device. In summary, it should be noted that the time required to clean the inner surface of the hollow body can be significantly reduced compared to devices known from the prior art. In addition, the amount of the first cleaning fluid required to clean the inner surface of the hollow body is also reduced. These advantages apply particularly to the production of semiconductor wafers.

• - Auflegen des Hohlkörpers auf die Auflagewand mit der Randfläche,
• - Dichtendes und lösbares Verbinden des Hohlkörpers mit der Auflagewand mittels der Verriegelungseinrichtung, wobei der Hohlkörper an der Randfläche gegenüber der Auflagewand abgedichtet wird,
  • ◯ Abgeben eines ersten Reinigungsfluids zum Reinigen der Hohlkörperinnenfläche mittels des ersten Reinigungskopfs der Reinigungseinrichtung, und Abführen des ersten Reinigungsfluids mittels des ersten Abführkanals, und/oder
  • ◯ Abgeben eines zweiten Reinigungsfluids zum Reinigen der Hohlkörperaußenfläche mittels des zweiten Reinigungskopfs der Reinigungseinrichtung, und Abführen des zweiten Reinigungsfluids mittels des zweiten Abführkanals.

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 previous embodiments, comprising the following steps:

• - Placing the hollow body on the support wall with the edge surface,
• - Sealing and detachable connection of the hollow body to the support wall by means of the locking device, whereby the hollow body is sealed at the edge surface opposite the support wall,
  • ◯ 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
  • ◯ 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.

The technical effects and advantages that can be achieved with the proposed method correspond to those that have been discussed for the present device. In summary, it should be noted that the hollow body inner surface and the hollow body outer surface can be cleaned independently of one another. Contamination of the first cleaning fluid, which is used to clean the hollow body inner surface, with particles that have been removed from the hollow body outer surface is excluded. With the proposed method, it is also possible to clean either only the hollow body outer surface or only the hollow body inner surface, if this is desired. Furthermore, the hollow body outer surface can be cleaned for a shorter time than the hollow body inner surface. In addition, it is also possible to clean both the hollow body outer surface and the hollow body inner surface at the same time.

• - Bewegen des Verschlusskörpers in die Offenstellung,
• - Ablegen des Deckels auf die Aufnahmeeinheit des Verschlusskörpers mit der Deckelaußenfläche und lösbares Befestigen des Deckels am Verschlusskörper,
• - Bewegen des Verschlusskörpers in die Verschlussstellung, und
• - Abgeben des ersten Reinigungsfluids zum Reinigen der Deckelinnenfläche mit dem weiteren ersten Reinigungskopf.

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

• - Moving the bolt body into the open position,
• - Placing the lid on the receiving unit of the closure body with the lid outer surface and detachably fastening the lid to the closure body,
• - Moving the bolt body into the locking position, and
• - Dispensing the first cleaning fluid to clean the inner surface of the lid with the additional first cleaning head.

The lid can be placed on the receiving unit using a gripping robot, for example. In the open position, the receiving unit is easily accessible, so that the lid can be placed and removed quickly and easily without the gripping robot having to perform complicated movements. In the closed position, the guidance of the first cleaning fluid is ensured, so that mixing with the second cleaning fluid is avoided for the reasons mentioned above. It should be noted that the proposed device can also be operated in such a way that only the lid and not the hollow body is cleaned. In this case, the through opening can be closed with a closure element.

• 1 eine prinzipielle Schnittdarstellung durch ein Ausführungsbeispiel einer Vorrichtung zum Reinigen von topfförmigen Hohlkörpern, insbesondere von Transportbehältern für Halbleiterwafer oder für EUV-Lithografie-Masken,
• 2 eine nicht maßstäblich vergrößerte Darstellung des in 1 definierten Ausschnitts A, und
• 3 eine nicht maßstäblich vergrößerte Darstellung des in 1 definierten Ausschnitts B.

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

• 1 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,
• 2 a non-scale enlarged representation of the 1 defined section A, and
• 3 a non-scale enlarged representation of the 1 defined section B.

In 1 an embodiment of a proposed device 10 for cleaning pot-shaped hollow bodies 12 is shown using 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. In addition, a support wall 20 is arranged in the housing 14 so that a closed process space 22 is created in the housing 14. The process space 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 arranged radially outside the through opening 24. In the embodiment shown, two through holes 28 are provided in the support wall 20 radially outside the locking device 26.

When the cover 18 is 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 space 22. The hollow body 12 has a bottom wall 32 and in this case four side walls 34, so that the pot-shaped hollow body 12 is essentially cuboid-shaped. However, it is entirely possible to provide the pot-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.

The hollow body 12 has an opening 36 which is arranged opposite the base wall 32 and which is enclosed by an edge surface 38 which is formed by the side walls. In the area of the edge surface 38, the hollow body 12 is designed like a flange in the embodiment shown. The hollow body 12 can be placed on the support wall 20 using this edge surface 38. 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 embodiment shown.

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 2 is the 1 marked area A is not shown to scale, but there is no exact match. For illustration reasons, the locking device 26 is not shown. 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.

In addition, the device 10 is equipped with a cleaning device 40, which has a first cleaning head 42, which protrudes beyond the through opening 24 and is thus arranged within the process space 22. net. When the hollow body 12 is connected to the support wall 20, the first cleaning head 42 is enclosed by the hollow body 12.

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 attached to the wall section 44 with a drive unit (not shown) so as to be rotatable 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 1 the locking body 48 is in the locking position.

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 detachably attached 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 is directly adjacent to 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 points towards the bottom wall 32 of the hollow body 12.

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

In 3 is the 1 marked area B is not shown enlarged to scale, although there is no exact match. It can be seen that in the housing 14 a housing seal 51 is arranged adjacent to the cleaning opening 46 and enclosing it. If 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.

In addition, 3 It can be seen 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 with which a flushing fluid, for example air or nitrogen, can be guided to the lid 52. The channel element 55 is constructed in such a way that it forms a gap 60 with the lid seal 53.

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 closure position.

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 as in 1 shown connected to the support wall 20. The second cleaning head 64 is rotatable about a second axis of rotation D2, the drive device used for this being not shown. Also not shown is an embodiment in which the second cleaning head 64 is not only rotatable, but also translatory or only translatory. In the embodiment shown, the first cleaning head 42 is not movable, but it can also be designed to be rotatable and/or translatory.

The device 10 is further provided with a fluid guide unit 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 to the second cleaning head 64. The fluid guide unit 66 has a first feed channel 68, with which the first cleaning fluid can be guided to the first cleaning head 42.

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.

Furthermore, the fluid guide unit 66 comprises a first discharge channel 70, with which the first cleaning fluid discharged from the first cleaning head 42 and from further first cleaning heads 58 can be discharged from the process chamber 22. The first discharge channel 70 has a first end 72, which is in fluid communication with the through-opening 24. As can be seen from the 1 As can be seen, the first discharge channel 70 widens in a funnel shape towards 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 ends flush with the through opening 24.

A first particle measuring device 741 is arranged in the first discharge channel 70, with which the particles that are in the first cleaning fluid and originate 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 that are in the first cleaning fluid and originate from the cover 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 holes 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 made very compact. An embodiment in which a further particle measuring device 74 is arranged in the second discharge channel 76 is not shown. At this point, it should be noted that the fluid guide unit 66 in 1 is only shown in principle. Due to the large number of channels nested and arranged in different levels, the representation of the fluid guide unit 66 according to 1 no claim to correctness. However, the expert will 1 can easily derive at least a functional structure of the fluid guide unit 66.

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

Using a handling device (not shown), for example a gripping 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 in such a way that the hollow body 12 rests with its edge surface 38 on the support wall 20, as shown in 1 is shown. 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 1 The cover 52 seals the cleaning opening 46.

A first cleaning fluid is now fed via the first feed channel 68 to the first cleaning head 42 and is discharged through first cleaning nozzles 78 so 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.

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 discharged through second cleaning nozzles 82 in order 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 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.

At the same time, a flushing 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 flushing fluid, but it is also possible to guide a first flushing fluid through the first channel 41 and a second flushing fluid that is different from the first flushing fluid through the second channel 57. The flushing 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 flushing 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.

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.

The flushing fluid, which is fed to the cover 52, flows through the gap 60 back into the secondary channel 84. The housing seal 51 prevents the flushing fluid from getting into the environment. The flushing fluid prevents the first cleaning fluid, which has been released by the further first cleaning head 58 and applied to the inner surface 54 of the cover, from getting to the cover seal 53, to which particles in the first cleaning fluid could adhere.

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.

The first cleaning fluid is used to remove particles that were on the hollow body inner surface 33 and the lid inner surface 54. The particles that come from the hollow body inner surface 33 are detected by the first particle measuring device 741 and the particles that come 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 designed in such a way that the number of particles that pass through the particle measuring device 74 within a certain time at a given volume flow is determined. This can be used to determine whether the hollow body inner surface 33 and the lid inner surface 54 have been cleaned to the desired extent or not. If, for example, 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 is continued. During this time, the hollow body 12 can be removed from the device by the gripping robot, which can save time.

As mentioned, a further particle measuring device 74 can be arranged in the second discharge channel 76. This further particle measuring device can detect the particles that originate from the hollow body outer surface 35. This information can also be included in the decision as to whether the cleaning process for the hollow body 12 can be aborted or not.

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

The second cleaning fluid, which has been discharged from 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, as a result of which particles originating from the hollow body outer surface 35 cannot get into the first cleaning fluid and thus onto the hollow body inner surface 33 or the lid inner surface 54.

In general, cleaning of the hollow body inner surface 33 and the lid inner surface 54 is more important than 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 prepared.

Now a first drying gas and a second drying gas, for example air or nitrogen, can be fed via the first feed channel 68 or the second feed channel in largely the same way as the first and second cleaning fluids to the first cleaning head 42, the further first cleaning head 58 and the second cleaning head 64. 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 or 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.

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.

After the drying process has been completed, 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.

Now, another hollow body 12 to be cleaned can be treated in the device 10 in the manner described.

List of reference symbols

10

contraption

12

Hollow body

14

Housing

16

Housing opening

18

Cover

20

Support wall

22

Process room

24

Passage opening

26

Locking device

28

Through hole

30

Transport container

32

Floor wall

33

Hollow body inner surface

34

Side wall

35

Hollow body outer surface

36

opening

38

Edge area

40

Cleaning facility

42

first cleaning head

44

Wall section

46

Cleaning opening

48

Closure body

50

Recording unit

52

Lid

54

Lid inner surface

56

Lid outer surface

58

another first cleaning head

64

second cleaning head

66

Fluid guide unit

68

first feed channel

70

first discharge channel

72

first end

74

Particle measuring device

76

second discharge channel

78

first cleaning nozzles

80

further first cleaning nozzles

82

second cleaning nozzles

84

Secondary channel

86

first drying nozzles

88

further first drying nozzles

90

second drying nozzles

92

Infrared diodes

D1

first axis of rotation

D2

second axis of rotation

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• US 5238703 A [0006]
• WO 2005001888 A [0006]
• EP1899084B1 [0006]

Claims (17)

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) - has a bottom wall (32) and one or more side walls (34) which form an inner surface (33) of the hollow body, and - has 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) - has a support wall (20) onto which the hollow body (12) can be placed with the edge surface (38), - a locking device (26) with which the hollow body (12) with the edge surface (38) can be connected to the support wall (20) in a sealing and detachable manner, - at least one through-opening (24) formed by the support wall (20) which is arranged radially inside the locking device (26) is, - a cleaning device (40) with which a first cleaning fluid can be discharged for cleaning the hollow body inner surface (33) 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 in fluid communication exclusively with the through opening (24) and with which the first cleaning fluid discharged by the cleaning device (40) can be discharged. Device (10) according to Claim 1 , characterized in that the first discharge channel (70) is connected with the first end (72) to the support wall (20) and encloses the through opening (24). Device (10) according to one of the Claims 1 or 2 , characterized in that the first discharge channel (70) widens in a funnel shape towards the first end (72). Device (10) according to one of the preceding claims, characterized in that the first discharge channel (70) at the first end (72) is flush with the through opening (24). Device (10) according to one of the preceding claims, characterized in that the cleaning device (40) has a first cleaning head (42) which protrudes beyond the through opening (24). Device (10) according to Claim 5 , characterized in that the first cleaning head (42) is rotatory and/or translatory movable. Device (10) according to one of the preceding claims, characterized in that the cleaning device (40) has a feed channel (68) for feeding 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 in sections to form a fluid guide unit (66). Device (10) according to one of the preceding claims, characterized in that a first channel (41) is arranged in the support wall (20), with which a flushing fluid can be guided to the edge surface (38). 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). 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 lid surface (54) for cleaning when the cleaning opening (46) is closed by the closure body (48) or by the lid (52). Device (10) according to Claim 10 , 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 cover (52) closes the cleaning opening (46). Device (10) according to one of the Claims 10 or 11 , characterized in that the device (10) has a second channel (57) with which a flushing fluid can be guided to the cover (52). Device (10) according to one 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 hollow body outer surface (35), 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. Device (10) according to Claim 13 , 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) which can be closed with a cover (18). Device (10) according to Claim 14 , 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). Device (10) according to one of the Claims 13 until 15 , characterized in that the second cleaning head (64) is U-shaped and can be moved rotationally and/or translationally in the process space (22). Device (10) according to Claim 5 , Claim 10 or Claim 13 , characterized in that the first cleaning head (42), the further first cleaning head (58) and/or the second cleaning head (64) have at least one drying nozzle (86, 88, 90) and/or an infrared diode (92).

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