Device and method for cleaning pot-shaped hollow bodies, in particular transport containers for semiconductor wafers or lithographic masks

Abstract

The invention relates to a device (92) for cleaning pot-shaped hollow bodies (94), comprising: a support wall (20) on which a hollow body (94) can be placed; at least one through hole (24) formed by the support wall (20); a cleaning device (40) that can eject a cleaning liquid for cleaning the lid support surface (96) when the hollow body (94) is placed on the support wall (20), the cleaning device (40) having a cleaning head (42) that protrudes above the through-hole (24) when the hollow body (94) is placed on the support wall (20); and a plurality of cleaning nozzles (100) through which the cleaning liquid can act on the cover support surface (96). The invention also relates to a method for cleaning pot-shaped hollow bodies (94) using such a device (92).

Description

[0001] The present invention relates to a device for drying canned hollow bodies, in particular to a drying device for semiconductor wafers or transport containers for extreme ultraviolet (EUV) lithography masks.

[0002] Today, highly integrated electronic circuits and other sensitive semiconductor components are manufactured in factories. In these factories, semiconductor wafers need to go through numerous processing steps, most of which are carried out in clean rooms. To ensure that the clean room is free of contamination, especially particle contamination, a great deal of effort is required. This is because particles that come into contact with the semiconductor material of the semiconductor wafer can affect its material properties, resulting in defects in the entire production batch and rendering it unusable, so it can only be scrapped.

[0003] As the integration density of semiconductor circuits continues to increase, maintaining cleanliness becomes increasingly important. Moreover, as the size of the clean room increases, the cost of maintaining cleanliness increases exponentially. Therefore, when semiconductor wafers are transported between different processing stations, they are not in an "open" state, but rather special transport containers (i.e., front-opening unified pods, FOUPs) are used. FOUPs are box-shaped transport containers that can hold a large number of semiconductor wafers and are usually closed by a detachable lid. When the lid is removed, the FOUPs are in a canned shape with a rectangular bottom surface. After the lid is closed, the semiconductor wafers inside can be transported between different clean rooms and protected from external contamination. When the FOUPs reach the processing station, they are opened, and the semiconductor wafers are taken out for processing. After processing, the wafers are put back into the FOUPs and then transported to the next processing station.

[0004] Since contamination of semiconductor wafers can cause long interruptions in production, it is necessary to clean the FOUPs regularly. During the process of loading and unloading semiconductor wafers, the FOUPs will be contaminated by the wear debris of the wafers.

[0005] Similarly, the transport containers for EUV lithography masks also have a similar situation. EUV lithography masks are used to manufacture tiny integrated circuits, and their transportation process also faces the same problems. When referring to FOUPs later, the relevant descriptions also apply to the transport containers for EUV lithography masks.

[0006] For example, devices for cleaning FOUPs can be learned from WO 2006 / 136224 A1, WO 2005 / 001888 A2, and DE 10 2020 129 469A1. Using these devices, the inner and outer surfaces of FOUPs can be cleaned. As mentioned before, FOUPs are enclosed by lids and are only opened when loading or unloading semiconductor wafers. Generally, the outer surface of FOUPs is more contaminated than the inner surface, and the lid support surface is particularly prominent. Taking the FOUPs in DE 10 2020 129 469A1 as an example, the lid support surface is located between the inner surface and the outer surface. In modern FOUPs, the lid support surface is formed by a step on the inner surface and is positioned by the inner surface when the lid is placed thereon. Due to contact with the lid, the lid support surface accumulates contaminants from the lid and is more contaminated than the rest of the inner surface. The contaminants on the inner surface may be directly deposited on the semiconductor wafer, causing the above-mentioned adverse effects.

[0007] An object of an embodiment of the present invention is to provide a device for cleaning a can-shaped hollow body, which solves the above problems in a simple and low-cost manner, especially reducing the number of defective and unusable production batches of semiconductor wafers. In addition, another object of an embodiment of the present invention is to provide a method for operating the device.

[0008] The present invention achieves the above objects through the features in claims 1 and 11. Advantageous embodiments are set forth in the dependent claims.

[0009] An embodiment of the present invention relates to a device for cleaning a can-shaped hollow body, especially for cleaning a semiconductor wafer or a transport container for EUV lithography masks, wherein the hollow body includes:

[0010] A bottom wall and one or more side walls, which together form the inner surface of the hollow body;

[0011] An opening opposite to the bottom wall, surrounded by the side walls;

[0012] A lid support surface formed by the side walls, on which the lid can be placed to enclose the hollow body,

[0013] wherein the device includes:

[0014] A support wall on which the hollow body can be placed;

[0015] At least one through hole formed in the support wall;

[0016] A cleaning device that can spray a cleaning liquid to clean the lid support surface when the hollow body is placed on the support wall (20);

[0017] The cleaning device has a cleaning head:

[0018] When the hollow body is placed on the support wall, the cleaning head protrudes above the through hole;

[0019] The cleaning head is provided with a plurality of cleaning nozzles, and the cleaning liquid is sprayed onto the lid support surface through these nozzles.

[0020] The support surface of the hollow body is placed on the support wall and can be optionally locked to fix the hollow body relative to the support wall. It should be noted that the support wall is different from the lid support surface. Subsequently, it is assumed that the lid support surface is part of the inner surface of the hollow body and is formed by the side wall of the hollow body.

[0021] The cleaning head is equipped with cleaning nozzles dedicated to cleaning the lid support surface, which can thoroughly clean this surface and significantly reduce the contaminants that may be deposited on the semiconductor wafer. Therefore, compared with the prior art devices, the number of defective and unusable production batches of semiconductor wafers can be significantly reduced.

[0022] According to another embodiment, the cleaning head can be provided with a plurality of drying nozzles, and drying gas is sprayed onto the lid support surface through these nozzles. In this solution, the device can not only be used for cleaning, but also perform subsequent drying of the hollow body. At the end of the cleaning process, the supply of the cleaning liquid is stopped, and instead, drying gas such as air or nitrogen is supplied to the drying nozzles to dry the lid support surface and remove the residual cleaning liquid.

[0023] In a further improved embodiment, the cleaning head can rotate or translate. With the mobility of the cleaning head, it can be adjusted according to the geometric characteristics of the lid support surface. In particular, the cleaning liquid can be sprayed at least approximately perpendicular to the lid support surface, making more effective use of the kinetic energy of the cleaning liquid to clean this surface.

[0024] In another improved embodiment, the cleaning liquid and / or the drying gas can be sprayed at a certain spraying angle. The cleaning head is provided with adjusting devices that cooperate with the cleaning nozzles and / or the drying nozzles to set the spraying angle. The spraying angle of the cleaning liquid determines the angle at which it impacts the lid support surface, and an angle of 90° or close to 90° is the ideal angle. By setting the spraying angle, the cleaning liquid can be sprayed at an angle of 90° or close to 90° onto the lid support surface and the adjacent area of the inner surface of the hollow body to simulate the geometric shape of the inner surface of the hollow body. The inner surface of the hollow body usually has a labyrinth-like structure. When using non-adjustable cleaning nozzles, there may be shadow areas that cannot or can only receive a small amount of cleaning liquid with sufficient kinetic energy. This embodiment can avoid such shadow areas and overall improve the cleaning effect.

[0025] In another embodiment, the cleaning head can be provided with a plurality of infrared diodes for heating the lid support surface. The infrared diodes heat the lid support surface to assist the drying process using the drying gas to remove the residual cleaning liquid.

[0026] In a further improved embodiment, the shape of the cleaning head is at least substantially consistent with the shape of the inner surface of the hollow body, so that the distance between the inner surface of the hollow body and the cleaning head remains constant or nearly constant. It has been found in practice that a distance of 1 - 50 mm, especially 10 - 30 mm, is beneficial for obtaining good cleaning effects. A smaller distance can generate a strongly directed air flow in the gap between the inner surface of the hollow body and the cleaning head, achieving better cleaning and drying effects. This distance does not require complete uniformity throughout the gap. For example, it can vary when there are protrusions, depressions, or undercuts on the side walls. At this time, the shape of the cleaning head is substantially complementary to the inner surface of the hollow body and does not follow individual protrusions or depressions on the side walls, facilitating the rapid retraction of the cleaning head into the internal space without affecting the cleaning and / or drying effects.

[0027] According to another embodiment, the device can be provided with at least one coupling unit for coupling sound waves into the cleaning liquid. Here, the sound waves especially refer to ultrasonic waves or megasonic waves. By definition, the frequency range of ultrasonic waves is approximately 20 kHz - 500 kHz, and the frequency range of megasonic waves is approximately 500 kHz - 3 MHz. It is more appropriate to completely wet the inner surface of the hollow body with the cleaning liquid or submerge the gap between the cleaning head and the inner surface of the hollow body, and couple the sound waves into the cleaning liquid. At this time, the cleaning liquid serves as a carrier for the sound waves, bringing energy into the cleaning liquid, making it easier to remove the particles adhering to the support surface of the lid and enhancing the cleaning effect. The input energy increases with the increase in the frequency of the coupled sound waves. Using megasonic waves can precisely transfer the energy to the support surface of the lid to be cleaned, achieving good cleaning effects.

[0028] In another embodiment, at least a part of the coupling unit can be integrated in a part of the cleaning nozzle or used in cooperation with a part of the cleaning nozzle. At this time, the cleaning nozzle can be designed as a "megasonic nozzle" to couple sound waves into the cleaning liquid ejected from the cleaning nozzle. In this way, it is not necessary to completely wet the entire inner surface of the hollow body with the cleaning liquid, and the amount of cleaning liquid used can be reduced.

[0029] In a further improved embodiment, the device can include a first drainage channel having a first end. The first end of the first drainage channel is only in fluid communication with the through hole, and the cleaning liquid ejected by the cleaning device is discharged through this drainage channel. In this embodiment, the cleaning liquid only contacts the inner surface of the hollow body. The outer surface of the hollow body is usually more contaminated than the inner surface. However, since the contaminants on the inner surface of the hollow body are closer to the semiconductor wafer, compared with the contaminants on the outer surface, they have a greater impact on the number of defective product batches of the semiconductor wafer. In this embodiment, the cleaning liquid only contacts the inner surface and will not be contaminated by the contaminants on the outer surface, and the cleaning effect will not be reduced.

[0030] In another embodiment, the drainage channel may be provided with a particle measuring device for detecting particles in the cleaning liquid. As previously mentioned, the cleaning liquid only contacts the inner surface of the hollow body and the lid support surface. Since the cleaning nozzle is used to clean the lid support surface, it can be considered that the particles detected by the particle measuring device mainly or mostly come from the lid support surface. For example, the particle measuring device can count the number of particles. If the number of particles is below a specific threshold, it can be considered that the hollow body has been cleaned properly, and the cleaning process can be terminated, thus saving time and cleaning liquid.

[0031] According to another embodiment, the cleaning head may be provided with a plurality of additional cleaning nozzles for cleaning the inner surface of the hollow body. These additional cleaning nozzles can be designed in the same way as the cleaning nozzles for cleaning the lid support surface, but the arrangement should ensure that the sprayed cleaning liquid does not hit the lid support surface. By cleaning the remaining inner surface with the additional cleaning nozzles, the number of defective and unusable production batches of semiconductor wafers can be further reduced.

[0032] In another embodiment, the cleaning head may include a flexible sheath, which can be switched between a contracted state and an expanded state by the cleaning liquid and / or drying gas. The cleaning nozzles, drying nozzles, and / or additional cleaning nozzles can be designed as holes or perforations in the flexible sheath, and the sheath can also be designed as a film. This can ensure that the cleaning liquid and / or drying gas introduced into the sheath can leave the cleaning head and be sprayed onto the lid support surface and / or the inner surface of the hollow body. The flexible sheath is designed to generate a certain flow resistance when the cleaning liquid and / or drying gas is introduced, and after overcoming this resistance, the cleaning liquid and / or drying gas can flow out of the sheath through the holes or perforations. This resistance causes the cleaning liquid or drying gas to accumulate in the sheath, prompting the sheath to change from the contracted state to the expanded state. By adjusting the pressure of the cleaning liquid or drying gas introduced into the sheath, the size of the sheath in the expanded state can be changed within a certain range, and then the distance between the inner surface of the hollow body and the cleaning head can be set to adapt to different-shaped hollow bodies.

[0033] One embodiment of the present invention relates to a method for cleaning a can-shaped hollow body, especially a semiconductor wafer or an EUV lithography mask transport container, using the above-mentioned device, and the method includes the following steps:

[0034] Place the hollow body on the support wall;

[0035] Spray the cleaning liquid from a plurality of cleaning nozzles on the cleaning device head to clean the lid support surface, and make the cleaning liquid spray onto the lid support surface;

[0036] Drain the cleaning liquid through the drainage channel.

[0037] The technical effects and advantages achieved by this method are consistent with those of the above-described device. In summary, this method can specifically clean the lid support surface. As previously mentioned, the lid support surface has a significant impact on the number of effective and unusable production batches of semiconductor wafers. By specifically cleaning the lid support surface, this quantity can be significantly reduced compared to the prior art processes.

[0038] In another embodiment, the method may include the following steps:

[0039] Detect particles in the cleaning liquid through a particle measuring device in the drainage channel;

[0040] Stop spraying the cleaning liquid when a particle-related threshold is either exceeded or fallen below.

[0041] For example, the particle measuring device can detect the number and / or particle size of the particles and define a relevant threshold. When this threshold is either exceeded or fallen below, it indicates that the hollow body has been sufficiently cleaned, and the cleaning process can be ended. This can not only record the cleaning degree of the hollow body but also end the cleaning operation in a timely manner when the hollow body meets the cleaning standard.

[0042] In a further improved embodiment, the method may include the following steps:

[0043] Completely submerge the space enclosed by the inner surface of the hollow body with a first cleaning liquid;

[0044] Couple acoustic waves into the first cleaning liquid through a coupling unit.

[0045] For example, the acoustic waves can be coupled in the form of ultrasonic waves or megasonic waves. This can introduce energy into the first cleaning liquid to assist in removing particles on the inner surface of the hollow body and improve the cleaning effect.

[0046] In another embodiment, the method may include the following steps:

[0047] Use a cleaning nozzle to clean the lid support surface;

[0048] Use an additional cleaning nozzle to perform out-of-phase cleaning on the inner surface of the hollow body.

[0049] As previously mentioned, the particle measuring device can detect particles in the cleaning liquid when it flows through the drainage channel, such as by counting. When cleaning the lid support surface, it can be considered that the particles in the cleaning liquid mainly come from this surface, and the same applies when cleaning the inner surface of the hollow body. Among the additional cleaning nozzles, the start time of some nozzles can be staggered from that of other nozzles to judge the pollution degree of different regions on the inner surface of the hollow body, especially the pollution situation compared to the lid support surface, and then infer defects in the semiconductor wafer production process.

[0050] The exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The drawings show:

[0051] Figure 1 is a basic cross-sectional view of a device in the prior art for cleaning a hollow can-shaped body, in particular a semiconductor wafer or a transport container for an EUV lithography mask;

[0052] Figure 2 is Figure 1 an enlarged view (not drawn to scale) of area A in

[0053] Figure 3 is a basic cross-sectional view of an embodiment of a device according to the present invention for cleaning a hollow can-shaped body, in particular a transport container for a semiconductor wafer or an EUV lithography mask.

[0054] Figure 1 A device 10 in the prior art for cleaning a hollow can-shaped body 12, such as the device described in DE10 2020 129 469 A1, is shown in a basic cross-sectional view. The device 10 has a housing 14 that forms a housing opening 16 and can be closed by a lid 18 that can be removed from the housing 14. A support wall 20 is provided inside the housing 14, forming a closed processing space 22. The processing space 22 is defined by the support wall 20, the housing 14 itself, and the lid 18. The support wall 20 forms a through hole 24, and a locking device 26 is provided radially outside the through hole 24. In the illustrated embodiment, two channel holes 28 are provided radially outside the locking device 26 in the support wall 20.

[0055] After removing the lid 18, the hollow body 12, in particular a transport container 30 for semiconductor wafers (i.e., FOUPs) or a transport container 30 for EUV lithography masks, can be placed in the processing space 22. The hollow body 12 has a bottom wall 32 and four side walls 34, and is in the shape of a parallelepiped. Of course, the hollow body 12 can also have other geometric shapes, such as cylindrical. The bottom wall 32 and the four side walls 34 form an inner hollow surface 33 and an outer hollow surface 35.

[0056] The hollow body 12 has an opening 36 opposite to the bottom wall 32, which is surrounded by an edge 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 edge surface 38. The edge surface 38 of the hollow body 12 can be placed on the support wall 20. In the illustrated embodiment, the through hole 24 in the support wall 20 and the opening 36 of the hollow body 12 have at least approximately the same size and geometric shape.

[0057] The locking device 26 is configured to make the through hole 24 at least approximately flush with the part of the inner hollow surface 33 of the hollow body adjacent to the through hole 24.

[0058] Figure 1 The marked area A in Figure 2 is shown enlarged but not to scale and is not an exact representation. For the sake of illustration, the locking device 26 is not shown. From Figure 2It can be seen that the support wall 20 includes a support wall portion 37, which forms a contact surface 39 that contacts the edge surface 38 of the transport container 30. The contact surface 39 of the support wall portion 37 is completely covered by the edge surface 38. The support wall portion 37 is provided with a first channel 41 leading to the contact surface 39, through which a flushing fluid (such as air or nitrogen) can be guided to the edge surface 38.

[0059] The device 10 is equipped with a cleaning device 40 having a first cleaning head 42 that protrudes above the through-hole 24 and is located within the processing 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.

[0060] The housing 14 further includes a wall portion 44 provided with a cleaning opening 46. The wall portion 44 is located on the side of the support wall 20 away from the locking device 26. The cleaning opening 46 can be at least partially closed by a closure body 48 that is rotatably fixed to the wall portion 44 about a first rotation axis D1 by a drive unit (not shown). The closure body 48 can move between an open position and a closed position. In the open position, the cleaning opening 46 is released, and in the closed position, the cleaning opening 46 is at least partially closed. Figure 1 In the figure, the closure body 48 is in the closed position.

[0061] The closure body 48 has a receiving unit 50 that can detachably fix the lid 52 closing the hollow body 12 to the closure body 48. The lid 52 forms an inner lid surface 54 and an outer lid surface 56. When the hollow body 12 is closed by the lid 52, the inner lid surface 54 directly abuts the inner surface 33 of the hollow body, that is, at this time, the inner lid surface 54 faces the bottom wall 32 of the hollow body 12.

[0062] In the illustrated embodiment, the receiving unit 50 is designed to interact with the lid 52 only through the outer lid surface 56.

[0063] The cleaning device 40 is further equipped with another first cleaning head 58 that is located near the closure body 48 when the closure body 48 is in the closed position.

[0064] The cleaning device 40 further includes a second cleaning head 64 that is substantially U-shaped and is at least partially located within the processing space 22. Different from the first cleaning head 42, as Figure 1 shown, when the hollow body 12 is connected to the support wall 20, the second cleaning head 64 is located outside the hollow body 12. The second cleaning head 64 can rotate about a second rotation axis, and the device for driving is not shown. There is also an embodiment not shown, in which the second cleaning head 64 can not only rotate but also translate, or only translate. In the illustrated embodiment, the first cleaning head 42 is immovable, but it can also be designed to be rotatable and / or translatable.

[0065] The apparatus 10 is further provided with a fluid conducting unit 66 that can conduct the first cleaning liquid to the first cleaning head 42 and another first cleaning head 58, and conduct the second cleaning liquid to the second cleaning head 64. The fluid conducting element 66 has a first supply channel 68 for conducting the first cleaning liquid to the first cleaning head 42.

[0066] For the sake of simplicity of illustration, the second supply channel for supplying the second cleaning liquid to the second cleaning head 64 is not shown in detail, but those skilled in the art can easily infer its design.

[0067] The fluid conducting unit 66 further includes a first drainage channel 70 that can drain the first cleaning liquid ejected from the first cleaning head 42 and another first cleaning head 58 from the processing space 22. The first end 72 of the first drainage channel 70 is in fluid communication with the through hole 24. From Figure 1 It can be seen that the first drainage channel 70 expands in a funnel shape towards the first end 72 and is connected to the support wall 20, making the first end 72 of the drainage channel flush with the through hole 24.

[0068] The fluid conducting unit 66 also has a second drainage channel 76, which is designed substantially the same as the first drainage channel 70, but is in fluid communication with two channel holes 28. Therefore, the first drainage channel 70 forms the radial inner wall of the second drainage channel 76, making the design of the fluid conducting unit 66 more compact. It should be noted that Figure 1 Only the fluid conducting unit 66 is shown schematically. Since Figure 1 there are multiple nested channels at different levels, this illustration cannot guarantee complete accuracy. At the same time, the flushing fluid is guided to the edge surface 38 through the first channel 41, and / or to the lid 52 through the second channel 57. The flushing fluid here can be the same, or the first flushing fluid can be guided through the first channel 41 and the second flushing fluid different from the first can be guided through the second channel 57. The flushing fluid guided to the edge surface 38 can prevent the first cleaning fluid and the second cleaning fluid from passing through the edge surface. Therefore, the flushing fluid forms a fluid seal between the first cleaning fluid and the second cleaning fluid, ensuring that the two do not mix, preventing the first cleaning fluid from being contaminated by the second cleaning fluid, and vice versa. However, it should be noted that the cleaning effect of the flushing fluid on the edge surface 38 is weak and can even be ignored.

[0069] The first cleaning fluid ejected from the first cleaning head 42 and acting on the inner surface 33 of the hollow body is discharged through the first drainage channel 70. Similarly, the first cleaning fluid ejected from another first cleaning head 58 and acting on the inner lid surface 54 is also discharged through the first drainage channel 70. The first drainage channel 70 is provided with a secondary channel 84 for discharging the first cleaning fluid used to clean the inner lid surface 54.

[0070] The flushing fluid guided to the lid 52 flows back through the gap 60 into the secondary channel 84. The housing seal 61 prevents the flushing fluid from leaking into the environment. The flushing fluid can prevent the first cleaning fluid ejected by another first cleaning head 58 and acting on the inner lid surface 54 from contacting the lid seal 53, avoiding the particles in the first cleaning fluid from adhering to the lid seal 53.

[0071] The flushing fluid guided to the edge surface 38 and / or the lid 52 can be applied with a sufficiently large pressure.

[0072] The particles located on the inner surface 33 of the hollow body and the inner lid surface 54 are removed by the first cleaning fluid. The second cleaning fluid ejected by the second cleaning head 64 and acting on the outer surface 35 of the hollow body is discharged through the second drainage channel 76. Therefore, the first cleaning fluid and the second cleaning fluid are discharged separately, so that the particles from the outer surface 35 of the hollow body do not enter the first cleaning fluid and thus do not adhere to the inner surface 33 of the hollow body or the inner lid surface 54.

[0073] If the inner surface 33 of the hollow body and the inner lid surface 54 have been cleaned to the desired extent, the cleaning process can be terminated regardless of the cleaning condition of the outer surface 35 of the hollow body.

[0074] Now, a first drying gas and a 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 in a manner substantially the same as that of the first cleaning fluid and the second cleaning fluid, through the first supply channel 68 or a second supply channel not shown here. The first cleaning head 42 is provided with a first drying nozzle 86, another first cleaning head 58 is provided with other first drying nozzles 88, and the second cleaning head is provided with a second drying nozzle 90. Through these nozzles, the first drying gas or the second drying gas can be ejected and act on the inner surface 33 of the hollow body, the inner lid surface 54, and the outer surface 35 of the hollow body. The first drying gas and the second drying gas discharge the first cleaning fluid and the second cleaning fluid from the device 10 and can also blow away the residues of the first cleaning fluid and the second cleaning fluid.

[0075] After the drying process is completed, the lid 18 is opened and the closure body 48 is moved to the open position. The cleaned hollow body 12 is taken out from the processing space. The receiving unit 50 is deactivated, so that the lid 52 can be removed from the closure body 48 and installed on the hollow body 12 to close it. Now, another hollow body 12 to be cleaned can be processed in the device 10 in the described manner.

[0076] Figure 3 A first embodiment of a device 92 for cleaning a tank-shaped hollow body 94 according to the present solution is shown in a basic sectional view. Here, the device 92 1 is shown. Here, the device 92 1The basic design and operating method are basically the same as the relevant description of the prior art device 10 shown in Figure 1 and Figure 2 . Therefore, Figure 3 only shows the important features related to the present invention.

[0077] If the hollow body 12 shown in Figure 1 and Figure 2 , which can be cleaned using the device 10, is compared with the hollow body 94 cleaned using the device 92 in this solution 1 , it will be found that the latter has, in addition to the edge surface 38, a lid support surface 96. The lid support surface 96 is part of the inner surface 33 of the hollow body and is formed by a step of the side wall 34.

[0078] The cleaning device 40 has a cleaning head 98, and the cleaning head 98 is equipped with a plurality of cleaning nozzles 100 through which the cleaning fluid can act on the lid support surface 96. In addition, the cleaning head 98 is also equipped with drying nozzles 102 through which the drying gas can act on the lid support surface 96. The cleaning nozzles 100 and the drying nozzles 102 can be designed the same, so they are not distinguished in Figure 3 . The cleaning nozzles 100 can also be designed to be able to spray both the cleaning fluid and the drying gas onto the lid support surface 96.

[0079] The cleaning nozzles 100 and / or the drying nozzles 102 are used in conjunction with an adjusting device 104, and through the adjusting device 104, the spraying angle α of the cleaning fluid and / or the drying gas can be set. For this purpose, the cleaning nozzles 100 and the drying nozzles 102 can be installed like golf balls. As an alternative or supplementary solution, especially the cleaning nozzles 100, can be installed on a tubular body 83 that can rotate around a third rotation axis D3, so that the spraying angle α can be set. In this way, the cleaning fluid and / or the drying gas can act on the lid support surface 96 vertically or almost vertically.

[0080] The device 92 1 also has at least one coupling unit 106 for coupling sound waves into the cleaning fluid. In the shown embodiment, part of the coupling unit 106 is integrated in part of the cleaning nozzles 100 and is designed as a so-called "megasonic nozzle". In this way, megasonic waves can be coupled into the cleaning fluid ejected from the cleaning nozzles 100.

[0081] In addition, other cleaning nozzles 108 are provided on the cleaning head 98, and the cleaning fluid can act on the inner surface 33 of the hollow body through these nozzles. In the illustrated embodiment, the other cleaning nozzles 108 are designed the same as the cleaning nozzles 100 for cleaning the lid support surface 96. They can also be used in particular in conjunction with an adjusting device 104 for adjusting the injection angle α (not shown in the figure). Additionally, other drying nozzles 110 can be provided on the cleaning head 98.

[0082] The cleaning nozzles 100 and the other cleaning nozzles 100 can be opened and closed independently. Therefore, different parts of the inner surface 33 of the hollow body can be cleaned first, and then other parts can be cleaned. For example, those parts with a relatively lighter degree of contamination according to experience can be cleaned first, and then the parts with a heavier degree of contamination can be cleaned.

[0083] The cleaning head 98 can be translated along and / or rotated about a fourth rotation axis D4 by a drive device (not shown). The cleaning head 98 also has a plurality of infrared diodes 112 for heating the lid support surface 96. Other infrared diodes 112 (not shown) can also be provided on the cleaning head 98 for heating the remaining part of the inner surface 33 of the hollow body.

[0084] The outer shape of the cleaning head 98 is at least approximately consistent with the shape of the inner surface 33 of the hollow body, so that the distance A between the inner surface 33 of the hollow body and the cleaning head 98 can be kept constant or almost constant. The aim here is to minimize the distance A as much as possible. On the one hand, it is to generate a strong and well-defined flow of cleaning fluid and / or drying gas in the intermediate space between the inner surface 33 of the hollow body and the cleaning head 98, and on the other hand, it is to minimize the volume of the intermediate space, thereby minimizing the amount of cleaning fluid and drying gas required. In the illustrated embodiment, the distance A should be between 10 millimeters and 30 millimeters. The intermediate space is designed in the form of an annular gap.

[0085] In addition, a particle measuring device 114 is provided in the first drainage channel 70 for determining the particles contained in the cleaning fluid.

[0086] As previously described, the device 92 of the present invention 1 operates in the same manner as Figure 1 and Figure 2is substantially the same as the prior art device described. However, it should be noted that the cleaning of the lid support surface 96 can be staggered in time from the cleaning of the rest of the inner surface 33 of the hollow body. When cleaning the lid support surface 96, the particles in the cleaning fluid flowing through the first drainage channel 70 can be considered to originate from the lid support surface 96. The particle measuring device 114 can characterize these particles based on relevant parameters such as the number of particles. Once the number of particles per unit time is below a certain threshold, the supply of the cleaning fluid to the lid support surface 96 can be interrupted. Now, the other cleaning nozzle 108 can be used to clean the rest of the inner surface 33 of the hollow body. For example, if the number of particles in the cleaning fluid is below a certain threshold when flowing through the first drainage channel 70, the supply of the cleaning fluid can also be stopped. When cleaning the lid support surface 95 and the inner surface 33 of the hollow body, the cleaning head 98 can rotate around the fourth rotation axis D4 and move along it. In addition, the adjusting device 104 can change the spraying angle α, and the coupling unit 106 can couple sound waves into the cleaning fluid.

[0087] Subsequently, the drying nozzle 102 can be used to spray dry gas onto the lid support surface 96. Simultaneously or staggered in time, the infrared diode 112 can heat the lid support surface 96. In this regard, the cleaning head 98 can also rotate around the fourth rotation axis D2. After the hollow body 94 is sufficiently dried, another hollow body 94 to be cleaned can be processed in the device 92 1 in the manner described. It should be noted here that Figure 3 the outer surface 35 of the hollow body and the lid 52 not shown in

[0088] Figure 4A and Figure 4B show a second embodiment of the device 92 for cleaning the can-shaped hollow body 94 according to the present solution in a substantially sectional view 2 The main difference between this embodiment and the embodiment of the device 92 shown in Figure 3 is that the cleaning head 98 has a flexible sheath 116 that can transition from a contracted state ( 1 ) to an expanded state ( Figure 4A ) and can reverse the transition. From Figure 4B ) and can reverse the transition. From Figure 4AStarting from the shown contracted state, a cleaning fluid or a drying gas is introduced into the flexible sheath 116 through the supply channel 68. Thereby, the flexible sheath 116 is filled with the cleaning fluid or the drying gas and continuously expands during this process. The flexible sheath 116 will keep expanding until the volume of the supplied cleaning fluid or drying gas is equal to the volume that leaves the flexible sheath 116 again through the cleaning nozzle 100, the drying nozzle 102, and / or other cleaning nozzles 108. For the sake of illustration, the cleaning nozzle 100, the drying nozzle 102, and / or other cleaning nozzles 108 are only shown in Figure 4B At this time, the flexible sheath 116 is in an expanded state. The dimensions of the flexible sheath 116 in the expanded state can be selected within a certain range by the cleaning fluid or drying gas used, as well as the temperature and pressure when the cleaning fluid or drying gas is introduced into the flexible sheath 116. Since the cleaning fluid and the drying gas flow along the inner surface 33 of the hollow body between the inner surface 33 of the hollow body and the cleaning head 98, contact between the flexible sheath 116 and the inner surface 33 of the hollow body can be prevented. To a certain extent, the flexible sheath 116 can also adapt to the shape of the inner surface 33 of the hollow body, especially in areas with undercuts, thereby forming a constant or nearly constant distance A, and this distance A can be minimized to a large extent, which is limited for the rigid cleaning head 98. As mentioned before, the distance A of the rigid cleaning head 98 is between 10 millimeters and 30 millimeters. When using the flexible sheath 116, this distance A can be further reduced. As mentioned before, a smaller distance A can generate a strong and distinct flow of the cleaning fluid and / or drying gas in the intermediate space between the inner surface 33 of the hollow body and the cleaning head 98, and can reduce the amount of cleaning fluid and drying gas required. These advantages can be achieved to a greater extent by using the flexible sheath 116. Also as mentioned before, the flexible sheath 116 can adapt to the shape of the inner surface 33 of the hollow body within a certain range. Therefore, the device can be used for cleaning and / or drying hollow bodies 94 of different shapes without conversion work.

[0089] List of reference numerals

[0090] 10 - Prior art device

[0091] 12 - Hollow body

[0092] 14 - Outer shell

[0093] 16 - Outer shell opening

[0094] 18 - Lid

[0095] 20 - Support wall

[0096] 22 - Processing space

[0097] 24 - Through hole

[0098] 26 - Locking device

[0099] 28 - Channel hole

[0100] 30 - Transport container

[0101] 32 - Bottom wall

[0102] 33 - Inner surface of the hollow body

[0103] 34 - Side wall

[0104] 35 - Outer surface of the hollow body

[0105] 36 - Opening

[0106] 37 - Support wall part

[0107] 38 - Edge surface

[0108] 39 - Contact surface

[0109] 40 - Cleaning device

[0110] 41 - First channel

[0111] 42 - First cleaning head

[0112] 44 - Wall part

[0113] 46 - Cleaning opening

[0114] 48 - Sealing body

[0115] 50 - Receiving unit

[0116] 52 - Lid

[0117] 54 - Inner lid surface

[0118] 56 - Outer lid surface

[0119] 58 - Another first cleaning head

[0120] 64 - Second cleaning head

[0121] 66 - Fluid conducting unit

[0122] 68 - First supply channel

[0123] 70 - First drainage channel

[0124] 72 - First end

[0125] 76 - Second drainage channel

[0126] 78 - First cleaning nozzle

[0127] 80 - Other first cleaning nozzles

[0128] 82 - Second cleaning nozzle

[0129] 83 - Tubular body

[0130] 84 - Secondary channel

[0131] 86 - First drying nozzle

[0132] 88 - Other first drying nozzles

[0133] 90 - Second drying nozzle

[0134] 92 - Device according to this solution

[0135] 92 1 、92 2 - Device according to this solution

[0136] 94 - Hollow body

[0137] 96 - Lid support surface

[0138] 98 - Cleaning head

[0139] 100 - Cleaning nozzle

[0140] 102 - Drying nozzle

[0141] 104 - Adjusting device

[0142] 106 - Coupling unit

[0143] 108 - Other cleaning nozzles

[0144] 110 - Other drying nozzles

[0145] 112 - Infrared diode

[0146] 114 - Particle measuring device

[0147] 116 - Flexible sheath

[0148] α - Injection angle

[0149] A - Distance

[0150] D1 - First rotation axis

[0151] D2 - Second rotation axis

[0152] D3 - Third rotation axis

[0153] D4 - Fourth rotation axis

Claims

1. An apparatus (92) for cleaning a hollow body (94) in the form of a can, in particular a transport container (30) for semiconductor wafers or extreme ultraviolet lithography masks, wherein the hollow body (94) comprises: - a bottom wall (32) and one or more side walls (34) which form an inner surface (33) of the hollow body; - an opening (36) which is arranged opposite the bottom wall (32) and is surrounded by the side walls (34); and - a lid support surface (96) formed by the side walls (34), on which a lid (52) can be placed to close the hollow body (94); wherein the apparatus (92) comprises: - a support wall (20) on which the hollow body (94) can be placed; - at least one through-hole (24) formed by the support wall (20); - a cleaning device (40) which, when the hollow body (94) is placed on the support wall (20), can eject a cleaning fluid for cleaning the lid support surface (96); wherein the cleaning device (40) has a cleaning head (98): - when the hollow body (94) is placed on the support wall (20), the cleaning head (98) projects above the through-hole (24) and / or can be inserted into the hollow body (94); - the cleaning head (98) has a plurality of cleaning nozzles (100) through which the cleaning fluid can act on the lid support surface (96).

2. The apparatus (92) according to claim 1, characterized in that the cleaning head (98) has a plurality of drying nozzles (102) through which drying gas can act on the lid support surface (96).

3. The apparatus (92) according to claim 1 or 2, characterized in that the cleaning head (98) is rotatable and / or translatable.

4. The apparatus (92) according to any one of the preceding claims or according to any one of claims 2 or 3, characterized in that the cleaning fluid and / or the drying gas can be ejected at an ejection angle (α), and the cleaning head (98) has an adjusting device (104) which cooperates with the cleaning nozzles (100) and / or the drying nozzles (102), and the ejection angle (α) can be set by means of this adjusting device.

5. The apparatus (92) according to any one of the preceding claims, characterized in that the cleaning head (98) has a plurality of infrared diodes (112) by means of which the lid support surface (96) can be heated.

6. The apparatus (92) according to any one of the preceding claims, characterized in that the outer shape of the cleaning head (98) is at least substantially the same as the shape of the inner surface (33) of the hollow body, so that the distance between the inner surface (33) of the hollow body and the cleaning head (98) is constant or almost constant.

7. The apparatus (92) according to any one of the preceding claims, characterized in that the apparatus (92) has at least one coupling unit (106) for coupling sound waves into the cleaning fluid.

8. The apparatus (92) according to any one of the preceding claims, characterized in that The device (92) includes a first drainage channel (70) having a first end (72). The first end (72) of the first drainage channel (70) is in fluid communication only with the through-hole (24). The cleaning fluid ejected by the cleaning device (40) can be discharged through the drainage channel (70), and a particle measuring device (114) for determining particles contained in the cleaning fluid is provided in the drainage channel.

9. The device (92) according to any one of the preceding claims, wherein, the cleaning head (98) has a plurality of other cleaning nozzles (108) for cleaning the inner surface (33) of the hollow body.

10. The device (92) according to any one of the preceding claims, wherein, the cleaning head (98) includes a flexible sheath (116), and the flexible sheath can be switched between a contracted state and an expanded state by the cleaning fluid and / or the drying gas.

11. A method for cleaning a can-shaped hollow body (94) using the device (92) according to any one of the preceding claims, particularly for cleaning a transport container for semiconductor wafers or extreme ultraviolet lithography masks. The method comprises the following steps: - placing the hollow body (94) on the support wall (20); - ejecting a cleaning liquid through a plurality of cleaning nozzles (100) provided on the cleaning head (98) of the cleaning device (40) to clean the lid support surface (96) so that the cleaning liquid acts on the lid support surface (96); - discharging the cleaning liquid through the first drainage channel (70).

12. The method according to claim 11, the method comprises the following steps: - determining the particles contained in the cleaning liquid by a particle measuring device (114) provided in the drainage channel (70); - stopping the ejection of the cleaning liquid when a threshold value related to the particles is exceeded or fallen below.

13. The method according to claim 11 or 12, the method comprises the following steps: - completely submerging the space defined by the inner surface (33) of the hollow body with a first cleaning liquid; - coupling acoustic waves into the first cleaning liquid through a coupling unit (106).

14. The method according to any one of claims 11 to 13, the method comprises the following steps: - cleaning the lid support surface (96) using the cleaning nozzles (100); - cleaning the inner surface (33) of the hollow body out of phase using other cleaning nozzles (100).

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