Apparatus for cleaning a pot-shaped hollow body, in particular a transport container for semiconductor wafers or lithography masks

Abstract

The present invention relates to an apparatus 10 for cleaning a pot-shaped hollow body 12, in particular a transport container 30 for semiconductor wafers or lithography masks. The hollow body 12 comprises a bottom wall 32 and one or more side walls 34 forming an inner hollow surface 33, and an opening 36 facing the bottom wall 32 and surrounded by an edge surface 38 of the side wall 34. The apparatus 10 includes a support wall 20 on which the hollow body 12 can be placed at the edge surface 38, a cleaning device 10 that can discharge a first cleaning fluid for cleaning the inner hollow surface 33 when the hollow body 12 is connected to the support wall 20, and a supply device 37 that is arranged within the support wall 20 or fixed to the support wall 20 and can supply a rinsing fluid to the edge surface 38. The supply device 37 comprises a movable element 38 that can be moved towards the edge surface 38 by the rinsing fluid.

Description

Technical Field

[0001] The present invention relates to a device for cleaning a pot-shaped hollow body, particularly a transport container for semiconductor wafers or lithography masks.

Background Art

[0002] The production of highly integrated electronic circuits and other sensitive semiconductor components is today carried out in factories where so-called semiconductor wafers pass through a large number of processing steps. Most of these processing steps are carried out with great effort in clean rooms maintained free of contaminants, particularly free of particles. The reason for such complex processing is that particles coming into contact with the semiconductor material of the semiconductor wafer can particularly affect the material properties of the semiconductor wafer, and as a result, the entire production batch becomes defective and cannot be used and has to be discarded.

[0003] As the integration density of semiconductor circuits has increased dramatically and the size of clean rooms has grown, the effort required to maintain a clean state has increased exponentially, making it even more important to maintain a clean state. Therefore, semiconductor wafers are not transported "unprotected" from one processing station to the next. Instead, special transport containers (so-called FOUPs (front opening unified pods), front opening unified pods) are used. A FOUP is understood to be a box-shaped transport container, usually injection-molded from plastic, into which a number of semiconductor wafers are inserted. A FOUP is usually closed with a removable cover. A FOUP has a pot-shaped basic shape that, without the cover, comprises a rectangular bottom surface and inner and outer surfaces that are separated from each other at the peripheral surface. The inserted semiconductor wafers can be transported from one clean room, where they are protected from the surroundings, to another clean room when the FOUP is closed with the FOUP's lid. When the FOUP reaches a processing station, the FOUP is opened, the semiconductor wafers are removed, and processed as appropriate. After the processing has been performed, the semiconductor wafers are transported and returned into the FOUP and then transported to the next processing station.

[0004] Since the production downtime due to contamination of semiconductor wafers is long, it is necessary to wash the FOUPs from time to time. FOUPs are particularly contaminated by wear debris of semiconductor wafers when taking them in and out of the FOUP.

[0005] Therefore, the same applies to the transport containers for lithography masks, particularly EUV lithography masks ("extreme ultraviolet radiation"). Lithography masks are used in the manufacture of very small integrated circuits. Lithography masks also need to be transported in the same way as semiconductors, and similar situations arise. When describing FOUPs below, the description in this regard also applies equally to the transport containers for lithography masks, particularly EUV lithography masks.

[0006] Devices for cleaning FOUPs are known, for example, from US Patent Application Publication No. 2002 / 0046760 (Patent Document 1), US Patent Application Publication No. 2003 / 0102015 (Patent Document 2), US Patent No. 8,591.664 (Patent Document 3), Japanese Patent Application Laid-Open No. 2005-109523 (Patent Document 4), International Publication No. 2005 / 001888 (Patent Document 5), and European Patent No. 1899084 (Patent Document 6).

[0007] In the case of such cleaning devices, both the inner and outer surfaces of the FOUP are cleaned. The outer surface of the FOUP is usually much more contaminated than the inner surface. As a result, the cleaning fluid accumulates both the fine particles generated from the outer surface and those generated from the inner surface during the cleaning procedure. The fine particles can thus be transported from the outer surface to the inner surface. However, a satisfactory cleaning result is achieved only when the number of fine particles is reduced below a certain value. Since the fine particles are generated from the outer surface, it is necessary to correspondingly execute the cleaning procedure for a long time so that a sufficient portion of the fine particles can be removed. This is disadvantageous in that, on the one hand, the amount of cleaning fluid required becomes relatively large, and on the other hand, the FOUP cannot be used to transport semiconductor wafers during the cleaning process. This increases the production cost of semiconductor wafers. Furthermore, there is a fact that the cleaning of the outer surface only contributes to reducing defective semiconductor wafers to a limited extent.

[0008] A wafer cleaning device capable of strictly separating the cleaning fluid for cleaning the inner surface of the FOUP from the cleaning fluid for cleaning the outer surface of the FOUP and removing it from the device is known from International Publication No. 2022 / 096657 (Patent Document 7). The separation of the fluids is performed at the peripheral surface of the FOUP. However, it is also desirable to prevent the penetration of fine particles from the outer surface into the cleaning fluid during the cleaning of the inner surface and the uncontrolled outflow of the cleaning fluid across the peripheral surface.

[0009] As mentioned, the FOUP is usually manufactured by an injection molding process. Therefore, in principle, the FOUP can only be produced with a relatively large tolerance. As a result, it is difficult to separate or seal the fluid at the peripheral surface.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Summary of the Invention

Problems to be Solved by the Invention

[0011] An object of an embodiment of the present invention is to provide a device for cleaning a pot - shaped hollow body, particularly a transport container for semiconductor wafers or lithography masks, thereby realizing an improvement for the above - mentioned drawbacks by technically simple and inexpensive means, and in particular, being able to reliably achieve sealing or fluid separation at the peripheral surface regardless of the tolerance of the FOUP to be cleaned.

Means for Solving the Problems

[0012] This object is achieved by the features specified in claim 1. Advantageous embodiments are the subject of the dependent claims.

[0013] One embodiment of the present invention relates to a device for cleaning a pot-shaped hollow body, in particular a transport container for semiconductor wafers or lithography masks. The hollow body has - a bottom wall and one or more side walls forming the inner surface of the hollow body, - an opening disposed on the side opposite the bottom wall and surrounded by the peripheral surface of the side wall and the device has - a support wall on which the peripheral surface of the hollow body can be placed, - a cleaning device capable of discharging a first cleaning fluid for cleaning the inner surface of the hollow body when the hollow body is connected to the support wall, - a supply device disposed within or fixed to the support wall and capable of guiding a flushing fluid to the peripheral surface, the supply device comprising a movable element movable towards the peripheral surface by the flushing fluid and comprises.

[0014] In the following embodiments, it is assumed that the hollow body is connected to the support wall.

[0015] In particular, nitrogen or compressed air, and particularly preferably, extremely clean dry air, also known as XCDA (extreme clean dried air), is used as the ejection fluid. The ejection fluid is introduced into the supply device at a sufficiently high pressure during the cleaning of the inner surface of the hollow body, where the ejection fluid moves the movable element towards the peripheral surface. The movable element can have a certain elasticity, and as a result, the movable element can conform to the range of the peripheral surface and contact the peripheral surface with at least substantially no interruption. The elasticity here is greater than that of the peripheral surface. In addition, when the movable element moves towards the peripheral surface and deforms accordingly, an expansion space can be provided in which the movable element can expand. As a result, a highly reliable seal is achieved regardless of the tolerance of the peripheral surface being affected. The seal prevents fine particles from moving from the outer surface of the hollow body into the first cleaning fluid during the cleaning of the inner surface of the hollow body. It is guaranteed that the fine particles removed by the first cleaning fluid are only those generated from the inner surface of the hollow body. The number of removed fine particles can be counted. When this number falls below a certain value, it is guaranteed that the inner surface of the hollow body has been sufficiently cleaned, so the cleaning can be terminated. The seal also has the effect of preventing the inner surface of the hollow body from being contaminated by the outer surface of the hollow body or surrounding fine particles.

[0016] According to a further embodiment, a recess in which the movable element is movably supported can be arranged in the support wall. By using the recess, it can be easily realized structurally that when pressurized using the ejection fluid, the movable element is induced to move towards the peripheral surface.

[0017] In a further developed embodiment, the movable element can comprise a sealing surface facing the peripheral surface, a distribution channel, and a plurality of discharge channels starting from the distribution channel and reaching the sealing surface. The movable element can be used as a simple sealing element that is pressed against the peripheral surface using the ejected fluid to seal it towards the peripheral surface, and the movable element comes into contact with the peripheral surface. However, the ejected fluid can also be used as a barrier medium, and for this purpose, it is not necessary to establish contact between the peripheral surface and the movable element. In this case, fluid sealing is achieved. The ejected fluid is guided to the sealing surface through the distribution channel. In this case, it is not necessary for the sealing surface to contact the peripheral surface. On the contrary, a sealing gap is generated. A certain flow of the ejected fluid has the effect here that the first cleaning fluid cannot exit through the sealing gap. However, in this case, the effect of the ejected fluid as a barrier medium can only be reliably established when the distance between the sealing surface and the peripheral surface is below a certain value. Therefore, it is also necessary to guide the movable element as close as possible to the peripheral surface. The difference in the distance between the sealing surface and the peripheral surface due to production inaccuracies can be compensated within a certain limit, resulting in a highly reliable seal.

[0018] In a further developed embodiment, the movable element can comprise a plurality of guiding channels extending on the sealing surface for guiding the ejected fluid along the sealing surface. Depending on the design of the device, it may be practical or necessary to guide the ejected fluid in a specific direction. The ejected fluid can be guided, for example, towards the first cleaning fluid that is to be guided together with the ejected fluid. From the opposite perspective, there may also be cases where it is desirable to guide the ejected fluid away from the first cleaning fluid. The ejected fluid can be guided, if necessary, up to the extent of the guiding channels along the peripheral surface while forming a sealing gap.

[0019] In a further embodiment, the movable element may be fully or partially elastic, and the shape of the movable element may be variable by the ejected fluid such that the movable element is movable towards the peripheral surface. In this embodiment, the movable element can be formed in a hose shape that expands as a result of pressurization by the ejected fluid and moves towards the peripheral surface as a result of the shape change. The term "elastic" should be understood as appropriate within the framework of this application. The required elasticity can be achieved, in particular, by selecting a suitable material, such as a material like rubber. The elasticity of the movable element is greater than the elasticity of the peripheral surface.

[0020] Thanks to the elastic design, the movable element can easily adapt to the range of the peripheral surface, thereby enabling either substantially continuous contact with the peripheral surface or a uniform design of the sealing gap. In this context, the term "movable element" can be understood within the framework of this application such that, on the one hand, the entire element moves towards the peripheral surface, and on the other hand, as a result of the shape change, at least a part of the movable element moves towards the peripheral region.

[0021] A further developed embodiment is that this device - at least one passage opening formed by a support wall, and - a first discharge channel having a first end and is characterized in that the first end of the first discharge channel is in fluid communication only with the passage opening so as to be able to discharge the first cleaning fluid ejected from the cleaning device.

[0022] The passage opening serves, inter alia, to discharge the first cleaning fluid from the hollow body. The passage opening is arranged such that only the first cleaning fluid is discharged through the passage opening, and for example, particulates generated from the outer surface of the hollow body are not discharged. Thus, it is ensured that only particulates generated from the inner surface of the hollow body are contained in the first discharge channel. The number of particulates in the first cleaning fluid flowing through the discharge channel can be determined. As soon as this number falls below a certain value, the cleaning of the inner surface of the hollow body can be terminated. The consumption of the first cleaning fluid can be limited to the necessary amount. Furthermore, the duration of the cleaning can also be shortened to the necessary extent.

[0023] According to a further embodiment, this device can comprise a locking device that can removably connect the peripheral surface of the hollow body to the support wall. The hollow body can be positioned with respect to the support wall using the locking device. During cleaning, especially during the pressurization of the movable element by the ejected fluid, the hollow body can be prevented from slipping.

[0024] In a further embodiment, it may be suitable for the passage opening to be arranged radially inside the locking device on the support wall. In this embodiment, the locking device is arranged on the support wall and thus in the vicinity of the peripheral surface. As an alternative, the locking device can engage, for example, with the bottom wall of the hollow body. However, in this case, the bottom wall and the side wall will be subjected to that much more load. In comparison, in this embodiment, the peripheral surface is pressed against the support wall by the locking device with a relatively large force, but the load on the bottom wall and the side wall can be kept small. Accordingly, the fact that the cleaning fluid is at a high pressure can also prevent the hollow body from slipping.

[0025] In a further embodiment where the bottom wall and the side wall form the outer surface of the hollow body, - the cleaning device comprises a second cleaning head capable of discharging a second cleaning fluid for cleaning the outer surface of the hollow body, and - the device comprises a second discharge channel capable of discharging the second cleaning fluid discharged from the second cleaning head may be suitable.

[0026] With respect to this point, this device includes a second discharge channel that can discharge the second cleaning fluid discharged from the second cleaning head. As mentioned initially, it is not essential to clean the outer surface of the hollow body as well. Nevertheless, for example, it may be desirable to keep the concentration of fine particles in a clean room low. In this embodiment, by discharging the second cleaning fluid separately from the first cleaning fluid, the outer surface of the hollow body can be cleaned. Mixing of the first cleaning fluid and the second cleaning fluid and an increase in the fine particle concentration in the first cleaning fluid caused by fine particles generated from the outer surface of the hollow body are prevented. As a result, when both the inner surface and the outer surface of the hollow body are cleaned, it is also prevented that fine particles generated from the outer surface of the hollow body can move to the inner surface of the hollow body. The cleaning process of the inner surface of the hollow body is not adversely affected by fine particles generated from the outer surface of the hollow body as a result. The measurement of the number of fine particles in the first cleaning fluid, which has already been mentioned, can also be carried out when using the second cleaning fluid without the measurement of fine particles generated from the outer surface of the hollow body being distorted. Similarly, the number of fine particles in the second cleaning fluid can be determined for the purpose of ending the cleaning of the outer surface of the hollow body when the number thereof also falls below a specific value.

[0027] Hereinafter, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

Brief Description of the Drawings

[0028]

Figure 1A

Figure 1B

Figure 1C

Figure 2

DETAILED DESCRIPTION OF THE INVENTION

[0029] FIG. 1A shows, with reference to a basic cross-sectional view, an embodiment of a device 10 according to a proposal for cleaning a pot-shaped hollow body 12. The device 10 comprises a housing 14 that forms a housing opening 16 that can be closed by a cover 18 removable from the housing 14. A support wall 20 is further disposed within the housing 14 such that a closed process space 22 is provided within 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 passage opening 24, and a locking device 26 is disposed radially outside the passage opening 24. In the illustrated embodiment, two passage holes 28 are provided radially outside the locking device 26 of the support wall 20.

[0030] When the cover 18 is removed, the hollow body 12, in particular a transport container 30 for semiconductor wafers or a transport container 30 for lithium masks, also called a FOUP, can be introduced into the process space 22. The hollow body 12 comprises a bottom wall 32 and in this case four side walls 34 such that the pot-shaped hollow body 12 has a substantially parallelepiped shape. However, it is of course also possible to make the pot-shaped hollow body 12 in another geometry, for example a cylindrical geometry. The bottom wall 32 and the four side walls 34 form an inner hollow surface 33 and an outer hollow surface 35.

[0031] The hollow body 12 has an opening 36 disposed on the side opposite the bottom wall 32 and surrounded by a peripheral surface 38 formed by the side walls. In the illustrated embodiment, the hollow body 12 is designed in a flange shape in the region of the peripheral surface 38. The peripheral surface 38 of the hollow body 12 can be placed on the support wall 20. The passage opening 24 of the support wall 20 and the opening 36 of the hollow body 12 are, in the illustrated embodiment, at least approximately the same size and have the same geometric shape.

[0032] The locking device 26 is further configured such that the passage opening 24 is at least substantially coplanar with the portion of the inner surface 33 of the hollow body adjacent to the passage opening 24.

[0033] The region A shown in FIG. 1A is not enlarged at a constant scale in FIG. 1B and does not exactly match. For illustrative purposes, the locking device 26 is not shown. It can be recognized from FIG. 1B that the support wall 20 has a recess 31 in which the supply device 37 is arranged and that the supply device 37 can guide the ejected fluid, such as air or nitrogen, to the peripheral surface 38. The supply device comprises a movable element 39 movably supported within the recess 31 according to the first embodiment. The movable element 39 is provided with a sealing surface 41 facing the peripheral surface 38. The movable element 39 further comprises a distribution flow path 43 and a plurality of discharge flow paths 45 extending from the distribution flow path 43 towards the sealing surface 41. Further, a supply flow path 47 capable of sending the ejected fluid into the distribution flow path 43 is arranged within the support wall 20.

[0034] The movable element 39 shown in FIG. 1B is enlarged and shown separately in FIG. 1C with the same cross-section as that used in FIGS. 1A and 1B. It can be recognized that a plurality of guiding flow paths 49 extend on the sealing surface 41.

[0035] Referring to FIG. 1A, the device 10 is equipped with a cleaning device 40 comprising a first cleaning head 42 protruding above the passage opening 24 and thus arranged within the process space 22. When the hollow body 12 is connected to the support wall 20, the first cleaning head 42 is surrounded by the hollow body 12.

[0036] The housing 14 further includes a wall portion 44 where the cleaning opening 46 is disposed. The wall portion 44 is located at a side portion of the side wall 20 away from the locking device 26. The cleaning opening 46 can be at least partially closed by a closure 48 fixed to the wall portion 44 rotatably about a first rotation axis D1 by a drive unit (not shown). The closure 48 can move between an open position where the closure 48 opens the cleaning opening 46 and a closed position where the closure 48 at least partially closes the cleaning opening 46. The closure 48 is in the closed position in FIG. 1A.

[0037] The closure 48 includes a receiving unit 50, and by the receiving unit 50, a cover 52 for closing the hollow body 12 in a closable manner can be releasably fixed to the closure 48. The cover 52 forms a cover inner surface 54 and a cover outer surface 56. The cover inner surface 54 is, here, the side surface of the cover 52 that directly abuts the inner surface 33 of the hollow body when the hollow body 12 is closed by the cover 52. In other words, the cover inner surface 54 faces the bottom wall 32 of the hollow body 12 in this case.

[0038] In the illustrated embodiment, the receiving unit 50 is designed to interact with the cover 52 only via the cover outer surface 56.

[0039] The cleaning device 40 is further equipped with a further first cleaning head 58 disposed in the vicinity of the closure 48 when the closure 48 is in the closed position.

[0040] The cleaning device 40 further includes a second cleaning head 64 that is substantially U-shaped and at least partially disposed within the process space 22. However, unlike the first cleaning head 42, the second cleaning head 64 is disposed outside the hollow body 12 when the hollow body 12 is connected to the support wall 20 as shown in FIG. 1A. The second cleaning head 64 is rotatable about a second axis of rotation D2, although the drive device used for this purpose is not shown. Further, in one embodiment where the second cleaning head 64 is not only rotationally movable but also translatable or only translatable, it is not shown. In the illustrated embodiment, the first cleaning head 42 is not movable, but it can also be designed to be rotatable and / or translatable.

[0041] The device 10 is further provided with a fluid guiding unit 66 that can guide a first cleaning fluid to the first cleaning head 42 and another first cleaning head 58, and can guide a second cleaning fluid to the second cleaning head 64. The fluid guiding element 66 includes a first supply channel 68 that can guide the first cleaning fluid to the first cleaning head 42.

[0042] Although a detailed view of the second supply channel for supplying the second cleaning fluid to the second cleaning head 64 is omitted for reasons of explanation, the design of the second supply channel should be easily inferable to those skilled in the art.

[0043] The fluid guiding unit 66 further includes a first discharge channel 70 that can discharge the first cleaning fluid discharged from the first cleaning head 42 and another first cleaning head 58 from the process space 22 again. The first discharge channel 70 has a first end 72 that is in fluid communication with the passage opening 24. As can be seen from FIG. 1A, the first discharge channel 70 expands in a funnel shape toward the first end 72, and the first end 72 of the discharge channel is connected to the support wall 20 such that it terminates in the same plane as the passage opening 24.

[0044] In the first discharge channel 70, a first particulate measurement device 741 is arranged which determines, in particular counts, the particulates generated from the inner surface 33 of the hollow body present in the first cleaning fluid. In the second discharge channel 742, a second particulate measurement device 742 is further arranged which determines, in particular counts, the particulates generated from the inner surface 54 of the cover present in the first cleaning fluid.

[0045] The fluid guiding unit 66 further comprises a second discharge channel 76 which is designed substantially identically to the first discharge channel 70 but is in fluid communication with the two passage holes 28. In this regard, the first discharge channel 70 forms the radially inner wall of the second discharge channel 76, whereby the fluid guiding unit 66 can be made in a very compact design. An embodiment in which another particulate measurement device 74 is arranged in the second discharge channel 76 is not shown. At this point, it should be pointed out that the fluid guiding unit 66 is only shown in principle in FIG. 1A. The drawing of the fluid guiding unit 66 according to FIG. 1A does not claim to be accurate since a large number of channels are nested and arranged at different levels. However, a person skilled in the art will be able to infer at least the functional design of the fluid guiding unit 66 without problems from FIG. 1A.

[0046] FIG. 2 shows again the supply device 37 with the movable element 39 according to the second embodiment. In the second embodiment, since the movable element 39 is elastic, when the ejection fluid is taken into the distribution channel 43 with sufficient pressure, the movable element 39 expands. As can be seen from FIG. 2, the movable element 39 is hose-shaped, and the recess 31 has a shape complementary to the hose-shaped movable element 39 in the region of the bottom of the recess 31. The bottom of the recess 31 has a semi-circular cross-section. When the ejection fluid is taken into the distribution channel 43, the movable element 39 can expand only towards the peripheral surface 38 due to the design of the recess 31, and as a result, it moves towards the peripheral surface 38.

[0047] Device 10 operates as follows. In an initial state not shown here, the cover 18 is open, and the second cleaning head 64 is rotated by 90° with respect to FIG. 1A such that the U-shaped portion of the second cleaning head 64 is perpendicular to the plane of FIG. 1A. The closure body 48 is in an open position where the closure body 48 is aligned substantially horizontally with respect to FIG. 1A.

[0048] The cover 52 is removed from the hollow body 12 by an operating device not shown here, for example a gripping robot, and placed on the receiving unit 50. The open hollow body 12 is incorporated into the process space 22 such that the peripheral surface 38 of the hollow body 12 is placed on the support wall as shown in FIG. 1A. The hollow body 12 is subsequently locked by the locking unit 26, whereby the hollow body 12 is connected to the support wall 20 and thus mounted in the process space 22. In this regard, the locking device 26 is equipped with a sealing agent not shown here, whereby the hollow body 12 is sealed against the support wall 20. The cover 18 is closed here. In addition, the receiving unit 50 of the closure body 48 is actuated such that the cover 52 is attached to the closure body 48. The closure body 47 rotates by 90° to the closed position as shown in FIG. 1A. Here, the cover 52 seals the cleaning opening 46.

[0049] The first cleaning fluid is here guided through the first supply channel 68 to the first cleaning head 42 and ejected through the first cleaning nozzle 78, as a result of which the inner surface 33 of the hollow body is cleaned by the first cleaning fluid. Another first cleaning head 58 is provided with another first cleaning nozzle 80 that sprays the first cleaning fluid onto the inner surface 54 of the cover, as a result of which the inner surface 54 of the cover is cleaned.

[0050] At the same time, a second cleaning fluid, which may coincide with the first cleaning fluid, is guided here through a second supply channel not shown here to the second cleaning head 64, where the second cleaning fluid is ejected from the second cleaning nozzle 82 to clean the outer surface 35 of the hollow body. In this regard, the second cleaning head 64 can rotate about the second rotation axis D2.

[0051] The first cleaning nozzle 78, another first cleaning nozzle 80, and the second cleaning nozzle 82 can be configured such that the injection angle α at which the first cleaning fluid and the second cleaning fluid are discharged can be set. For this purpose, the first cleaning nozzle 78, another first cleaning nozzle 80, and the second cleaning nozzle 82 can be supported in a spherical head shape.

[0052] At the same time, while using the supply device 37, the ejected fluid is guided toward the peripheral surface 38. In this regard, the ejected fluid, although detailed illustration is omitted, is sent into the supply channel 47 by a pump (see FIG. 1B), where the ejected fluid is at a sufficiently high pressure. The ejected fluid moves from the supply channel 47 into the distribution channel 43 and from the distribution channel 43 into the discharge channel 45. Most of the ejected fluid collides with the peripheral surface 38 when leaving the discharge channel 45. A part of the ejected fluid flows through the induction channel 49 toward the passage opening 24. This causes the entire flow of the ejected fluid toward the passage opening 24. As a result, the ejected fluid flows into the first cleaning fluid while forming a sealing gap between the sealing surface 41 and the peripheral surface 38.

[0053] According to the first embodiment, the movable element 39 rises due to the formed back pressure and moves toward the peripheral surface 38. In the second embodiment, the movable element 39 expands and, as a result, moves toward the peripheral surface 38. In either case, a uniform sealing gap is formed even if the peripheral surface 38 has irregularities due to tolerances.

[0054] An expansion space 83 is provided to enable the movement and / or deformation or expansion of the movable element 39. With respect to FIG. 1B, in the first embodiment, the expansion space 83 is formed by an annular gap between the movable element 39 and the recess 31. The annular gap is dimensioned such that, on the one hand, the movable element 39 can move toward the peripheral surface 38 and, on the other hand, some guidance is provided to prevent the movable element 39 from tilting within the recess 31.

[0055] As mentioned above, in the second embodiment, while the movable element 39 is circular, the bottom of the concave portion 31 is semi-circular. The expansion space 82 is formed between the movable element 39 and the peripheral surface 38.

[0056] The ejected fluid realizes a state where neither the first cleaning fluid nor the second cleaning fluid can cross the peripheral surface 38. The ejected fluid thus performs a fluid seal between the first cleaning fluid and the second cleaning fluid. As a result, a situation where the first cleaning fluid and the second cleaning fluid cannot mix is ensured. Contamination of the first cleaning fluid by the second cleaning fluid and vice versa is prevented.

[0057] The first cleaning fluid discharged from the first cleaning head 42 and sprayed on the inner surface 33 of the hollow body is discharged from the first discharge channel 70. The same also applies to the first cleaning fluid discharged from another first cleaning head 58 and sprayed on the inner surface 54 of the cover. The ejected fluid is also discharged through the first discharge channel together with the first cleaning fluid. The first discharge channel 70 includes a secondary channel 84 that opens into the first discharge channel 70 and discharges the first cleaning fluid used to clean the inner surface 54 of the cover.

[0058] Particles on the inner surface 33 of the hollow body and the inner surface 54 of the cover are removed by the first cleaning fluid. Particles generated from the inner surface 33 of the hollow body are detected by the first particle measurement device 741, and particles generated from the inner surface 54 of the cover are detected by the second particle measurement device. In this regard, the first particle measurement device 741 and the second particle measurement device 742 are configured to determine the number of particles passing through the particle measurement device 74 at a given volume flow rate within a certain period of time. Thereby, it is possible to determine whether the inner surface 33 of the hollow body and the inner surface 54 of the cover have been cleaned to a desired degree. For example, if the inner surface 33 of the hollow body is sufficiently clean, the cleaning process of the hollow body 12 can be terminated while continuing the cleaning process of the inner surface 54 of the cover. During that time, the hollow body 12 can be taken out of the device by the robot gripper, thereby saving time.

[0059] As mentioned, another particulate measurement device 74 can be arranged in the second discharge channel 76. Particulates generated from the outer surface 35 of the hollow body can be detected by this another particulate measurement device. This information can also be incorporated into the determination of whether to terminate the cleaning process of the hollow body 12. When the filling amount of the first cleaning fluid corresponding to the particulates generated from the inner surface 33 of the hollow body does not exceed a specific value, the first cleaning fluid can also be used for cleaning the outer surface 35 of the hollow body.

[0060] An embodiment in which the particulate measurement device 74 is arranged downstream of the opening of the secondary channel 84 into the first discharge channel 70 is not shown. In this case, it is not possible to distinguish whether the particulates are generated from the inner surface 54 of the cover or from the inner surface 33 of the hollow body. Still, when the number of particulates falls below a certain level, the cleaning process can be terminated.

[0061] The second cleaning fluid discharged from the second cleaning head 64 and sprayed onto the outer surface 35 of the hollow body is discharged through the second discharge channel 76. As a result, the first cleaning fluid and the second cleaning fluid are discharged separately from each other, so that the particulates generated from the outer surface 35 of the hollow body do not flow into the first cleaning fluid and thus cannot flow onto the inner surface 33 of the hollow body or the inner surface 54 of the cover.

[0062] The cleaning of the inner surface 33 of the hollow body and the inner surface 54 of the cover is generally more important than the cleaning of the outer surface 35 of the hollow body. When it is found that the inner surface 33 of the hollow body and the inner surface 54 of the cover have been cleaned to the desired extent, the cleaning process can be terminated regardless of the degree to which the outer surface 35 of the hollow body has been prepared.

[0063] Here, the first drying gas and the second drying gas, such as air or nitrogen, can be guided to the first cleaning head 42, another first cleaning head 58, and the second cleaning head 64 through the first supply channel 68 or the second supply channel, in substantially the same manner as the first cleaning fluid and the second cleaning fluid. The first cleaning head 42 is provided with a first drying nozzle 86, another first cleaning head 84 is provided with another first drying nozzle 88, and the second cleaning head is provided with a second drying nozzle 90, through which the first drying gas or the second drying gas can be discharged and sprayed onto the inner surface 33 of the hollow body, the inner surface 54 of the cover, and the outer surface 35 of the hollow body. The first drying gas and the second drying gas expel the first cleaning fluid and the second cleaning fluid from the device 10. Further, the residues of the first cleaning fluid and the second cleaning fluid can be blown away.

[0064] The first cleaning head 42, another first cleaning head 58, and the second cleaning head are further provided with infrared diodes 92, by which the residues of the first cleaning fluid and the second cleaning fluid can be heated and evaporated, and as a result, the residues can be removed from the device 10 by the first drying gas and the second drying gas.

[0065] After the drying process is completed, the cover 18 is opened and the closing body 48 is moved to the open position. The cleaned hollow body 12 is removed from the process space. The receiving unit 50 is stopped, and as a result, the cover 52 can be removed from the closing body 48 and supplied to the hollow body 12 to close the hollow body 12.

[0066] In this way, other hollow bodies 12 to be cleaned can be processed within the device 10 according to the method described herein.

Explanation of Reference Numerals

[0067] 10 Device 12 Hollow body 14 Housing 16 Housing opening 18 Cover 20 Support wall 22 Process space 24 passage opening 26 locking device 28 passage hole 30 transport container 31 recess 32 bottom wall 33 inner surface of the hollow body 34 side wall 35 outer surface of the hollow body 36 opening 37 supply device 38 peripheral surface 39 movable element 40 cleaning device 41 sealing surface 42 first cleaning head 43 distribution flow path 44 wall portion 45 discharge flow path 46 cleaning opening 47 supply flow path 48 closing body 49 guiding flow path 50 receiving unit 52 cover 54 inner surface of the cover 56 outer surface of the cover 58 another first cleaning head 64 second cleaning head 66 fluid guiding unit 68 first supply flow path 70 first discharge flow path 72 first end 74 particulate measurement device 76 second discharge flow path 78 first cleaning nozzle 80 another first cleaning nozzle 82 second cleaning nozzle 83 expansion space 84 secondary flow path 86 first drying nozzle 88 another first drying nozzle 90 second drying nozzle 92 infrared diode D1 first rotation axis D2 second rotation axis

Claims

1. A device (10) for cleaning a pot-shaped hollow body (12), in particular a transport container (30) for semiconductor wafers or lithography masks, wherein the hollow body (12) has - a bottom wall (32) and one or more side walls (34) forming an inner surface (33) of the hollow body, - an opening (36) arranged on the side opposite to the bottom wall (32) and surrounded by a peripheral surface (38) of the side wall (34) and the device (10) comprises - a support wall (20) on which the peripheral surface (38) of the hollow body (12) can be placed, - a cleaning device (40) capable of discharging a first cleaning fluid for cleaning the inner surface (33) of the hollow body (12) when the hollow body (12) is connected to the support wall (20), - a supply device (37) arranged in the support wall (20) or fixed to the support wall (20) and capable of guiding the ejected fluid to the peripheral surface (38), the supply device (37) comprising a movable element (39) movable towards the peripheral surface (38) by the ejected fluid Device (10).

2. The device (10) according to claim 1, characterized in that a recess (31) in which the movable element (39) is movably supported is arranged in the support wall (20).

3. The movable element (39) has - a sealing surface (41) facing the peripheral surface (38), - a distribution channel (43) and a plurality of discharge channels (45) starting from the distribution channel (43) and leading to the sealing surface (41) The device (10) according to claim 1 or 2, characterized in that it comprises.

4. The device (10) according to claim 3, characterized in that the movable element (39) comprises a plurality of guiding channels (49) extending on the sealing surface (41) for guiding the ejected fluid along the sealing surface (41).

5. The device (10) according to any one of claims 1 to 4, characterized in that the movable element (39) is completely or partially elastic and the shape of the movable element (39) is variable by the ejected fluid such that the movable element (39) is movable towards the peripheral surface (38).

6. The device has - at least one passage opening (24) formed by the support wall (20), - a first discharge channel (70) having a first end (72) The device (10) according to any one of claims 1 to 5, comprising, wherein the first end (72) of the first discharge channel (74) is in fluid communication only with the passage opening (24) so as to be able to discharge the first cleaning fluid discharged from the cleaning device (40).

7. The device (10) according to any one of claims 1 to 6, characterized in that the device comprises a locking device (26) capable of removably connecting the peripheral surface (38) of the hollow body (12) to the support wall (20).

8. The device (10) according to claim 7, characterized in that the passage opening (24) is arranged radially inside the locking device (26) on the support wall (20).

9. The bottom wall (32) and the side wall (34) form an outer surface (35) of the hollow body, - the cleaning device (40) comprises a second cleaning head unit (64) capable of discharging a second cleaning fluid for cleaning the outer surface (35) of the hollow body; - the device (10) comprises a second discharge channel (76) capable of discharging the second cleaning fluid discharged from the second cleaning head (64). The device (10) according to any one of claims 1 to 8, characterized in that.

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