Device and method for treating wafers using separating elements

Abstract

The invention relates to a device for treating wafers using a treatment liquid, having a basin, a perforated plate, a filling tube, and separating elements. The basin is used to receive the treatment liquid and the wafers to be treated. The perforated plate separates the basin into an upper region and a lower region, said perforated plate having holes which fluidically connect the lower region and the upper region. The filling tube is arranged in the lower region of the basin and has filling tube openings along the longitudinal direction of the filling tube. The separating elements are arranged in the lower region of the basin between at least some of the filling tube openings of the filling tube and extend in a direction which intersects the longitudinal direction of the filling tube in order to at least reduce the flow of the treatment liquid in the longitudinal direction of the filling tube between said tube filling openings.

Description

[0001] Apparatus and method for treating wafers using separating elements

[0002] Description

[0003] The present invention relates to devices and methods for treating wafers and, in particular, to devices and methods for treating wafers in batch operation, in which a plurality of wafers are placed in a wafer carrier, for example a wafer carrier, which is usually referred to as a basket or carrier, in a basin and treated there with a treatment liquid.

[0004] Various methods for treating wafers with liquids are known from the prior art. EP 0 762 482 B1, for example, describes devices and methods for etching wafers, in which a wafer carrier is arranged in a tank. A lateral wall is arranged in the tank, which has holes through which treatment liquid is supplied from one side of the etching tank. The treatment liquid flows through the etching tank in such a way that a superficial horizontal laminar flow is formed near the surface of the liquid and a rotating flow is effected near the semiconductor wafers, essentially concentric with the respective wafer center.

[0005] TW 202003124 A describes a device for cleaning wafers in a batch process, in which a wafer carrier is placed into a basin. In a lower region of the basin, a perforated plate with a plurality of evenly spaced openings is provided. Below the perforated plate, pipes are provided which have openings directed towards a lower wall of the basin so that liquid can be pumped through the openings of the pipes and from there through the perforated plate and past the wafers to clean the wafers. It is described that during rinsing, the wafers are first rinsed from bottom to top and then from top to bottom.

[0006] One problem with known processes is that uniform treatment of the wafers is difficult to achieve during batch processing. The treatment intensity, for example the etching rate, can depend on the flow through a circulation of the treatment medium, on varying homogeneity of the treatment medium over a base area of ​​the bath, within the wafer carrier or between different wafer carriers within a bath. Particularly with a large number of wafer carriers within a batch process, for example six wafer carriers or eight wafer carriers, the flow through the wafer carriers in the tank can be asymmetrical, with the flow through the middle baskets being different from the flow through the outer baskets. In a batch with eight baskets, the flow at the bath surface can run towards the side wall of the tank, where lateral overflow can occur.

[0007] To solve these problems, one conceivable approach is to guide the flow by designing a perforated plate below or to the side of the wafer carriers; reference can be made to the above-mentioned publications. Inlet tubes below the wafer carriers could be designed to locally modify the flow. Furthermore, diffuse media distribution via gas bubbles could be used in addition to circulation.

[0008] The object of the present invention is to provide devices and methods for uniformly treating wafers in a wafer carrier with a treatment liquid.

[0009] This object is achieved by an apparatus for treating wafers according to claim 1 and a method for treating wafers according to claim 18.

[0010] Examples provide a device for treating wafers with a treatment liquid, having the following features: a basin for receiving the treatment liquid and the wafers to be treated; a perforated plate which separates the basin into an upper region and a lower region, wherein the perforated plate has holes which fluidically connect the lower region and the upper region; and a filling pipe which is arranged in the lower region of the basin and has filling pipe openings along its longitudinal direction, characterized by

[0011] Separating elements in the lower region of the basin, which are arranged between at least some filling pipe openings of the filling pipe and extend in a direction that intersects the longitudinal direction of the filling pipe in order to at least reduce flows of the treatment liquid in the longitudinal direction of the filling pipe between the at least some of the filling pipe openings.

[0012] Examples of the invention are based on the finding that by providing the separating elements, the flow of the treatment fluid in the longitudinal direction of the filling tube can be reduced, allowing a more uniform flow through one or more wafer carriers arranged above the perforated plate. This allows for a more uniform treatment of the wafers with the treatment fluid, which can also be referred to as the treatment medium. Furthermore, this enables more effective use of the medium. The treatment fluid can be, for example, cleaning fluids or etching fluids commonly used for the treatment of silicon wafers.

[0013] In some examples, the dividing elements are designed to divide the lower area of ​​the basin into compartments that extend laterally outward from the filling pipe. Such a division makes it possible to limit the flow of the treatment liquid in the longitudinal direction to the respective compartments, whereby a circular flow can be achieved in the respective compartments, which can effectively achieve uniform flow through the perforated plate arranged above.

[0014] In some examples, the filling pipe openings are oriented toward the bottom of the tank. In some examples, a separator element is provided between each adjacent pair of filling pipe openings. This allows for a significant reduction or suppression of treatment fluid flows in the longitudinal direction of the filling pipe.

[0015] In examples, the separating elements extend in the direction that intersects the longitudinal direction of the filling tube over a region of the perforated plate in which the holes are provided. This makes it possible to reduce or suppress the flow of the treatment liquid in the longitudinal direction of the filling tube over the entire region of the perforated plate in which the holes are provided in the transverse direction. As a result, a uniform flow can be achieved over this entire region, over which one or more wafer carriers can be arranged. In examples, the direction in which the separating elements extend is perpendicular to the longitudinal direction of the filling tube. The direction in which the separating elements extend is understood to mean the direction of the longest extent of the separating elements, wherein the separating elements can have an elongated, plate-like shape.Examples thus effectively enable a flow of the treatment liquid perpendicular to the longitudinal direction of the filling pipe in order to achieve a uniform flow of the treatment liquid above the perforated plate.

[0016] In examples, the filling pipe is fluidically coupled to a treatment liquid supply line in a longitudinally central region thereof, so that a uniform flow of the treatment liquid through the filling pipe starting from the treatment liquid supply line can be achieved.

[0017] In some examples, the upper region of the basin has a receiving area for one or more wafer carriers, in each of which wafers are arranged side by side with a distance between them. In some examples, the upper region has a plurality of receiving areas for receiving a plurality of wafer carriers side by side in the longitudinal direction of the filling tube and / or transversely to the longitudinal direction of the filling tube. In some examples, the holes in the perforated plate are distributed at least across the receiving area(s) to thus enable uniform flow through the wafer carriers in the receiving area(s).

[0018] In examples, guide elements are further arranged in addition to the outer walls of the basin in the upper region of the basin, the guide elements laterally delimiting the receiving area of ​​at least one wafer carrier in order to concentrate a flow of the treatment liquid on the receiving area. Laterally is understood to mean laterally with respect to the longitudinal direction of the filling pipe. The guide elements can be elements next to the wafer carriers that separate the wafer carriers, force the flow through the wafer carriers and thus to the surfaces of the wafers, i.e. the wafer sides, and prevent the flow from escaping sideways. The guide elements thus enable targeted guidance of the treatment liquid through the wafer carriers and thus also a homogeneous flow through them. The guide elements can thus further improve the homogenization of the treatment with a treatment liquid.The guide elements are part of the wafer processing device and not part of the wafer carrier(s). Therefore, the guide elements do not move with the wafer carrier(s) but are stationary within the wafer processing device.

[0019] In some examples, the guide elements delimit the receiving area of ​​the at least one wafer carrier on two sides that extend parallel to the longitudinal extent of the filling tube. Typically, the dimensions of the wafer carriers are larger in the longitudinal direction of the filling tube than in the direction perpendicular to it, i.e., the transverse direction. Thus, such examples allow the flow to be concentrated onto the receiving area via both longer sides of the wafer carrier.

[0020] In some examples, the guide elements are further configured to position the at least one wafer carrier in the basin. Thus, examples enable precise positioning of the wafer carrier(s) in the basin at a defined position above the perforated plate.

[0021] In some examples, the distance between the guide elements transverse to the longitudinal direction of the filling tube can correspond to a dimension of the wafer carrier transverse to the longitudinal direction of the filling tube. This allows for precise positioning of the wafer carrier(s) and also prevents liquid from flowing past the wafer carriers laterally.

[0022] In some examples, the guide elements are configured to facilitate the positioning of wafer carriers having end plates spaced apart from one another in the longitudinal direction of the filling tube. In such examples, a length of the guide elements in the longitudinal direction of the filling tube can correspond to a distance between these end plates of the wafer carrier. Thus, such examples also enable precise positioning of the wafer carrier(s) in the longitudinal direction of the filling tube.

[0023] In some examples, a plurality of corresponding guide elements can be provided that laterally delimit receiving areas for a plurality of wafer carriers, so that a plurality of wafer carriers, for example, four, six, or more wafer carriers, can be placed at defined positions in the upper region of the basin. At least one of the guide elements can be configured to be arranged between two adjacent receiving areas and thus delimit the mutually facing sides of the two adjacent receiving areas.

[0024] In some examples, the device further comprises a pump for pumping the treatment liquid into the filling pipe and through the filling pipe openings. In some examples, the liquid is pumped through the filling pipe openings toward the bottom of the basin, wherein the liquid can be distributed transversely in the lower region of the basin and can pass through the perforated plate into the upper region of the basin.

[0025] Examples provide a method for treating wafers with a treatment liquid using one of the devices as described herein. At least one wafer carrier is introduced into the upper region of the basin. Treatment liquid is pumped by means of the pump into the filling tube and through the filling tube openings, for example, towards the underside of the basin. This causes flows of the treatment liquid through the holes in the perforated plate into the upper region of the basin in order to treat wafers in the wafer carrier with the treatment liquid. The separating elements at least reduce flows of the treatment liquid in the longitudinal direction of the filling tube between at least some of the filling tube openings, and thereby reduce differences between flows of the treatment liquid through holes in the perforated plate arranged in the longitudinal direction of the filling tube.This allows for a more uniform flow through the wafers in the wafer carrier, as described above. This effect can also be achieved for multiple wafer carriers if the upper section of the tank is designed to have multiple receiving areas for multiple wafer carriers.

[0026] In examples of this method, the described guide elements can be used as a guide when introducing the at least one wafer carrier into the upper region of the basin, so that the wafer carrier can be positioned at a defined position in the basin or the wafer carriers can be positioned at defined positions in the basin.

[0027] Short description of the drawings

[0028] Examples of the invention are explained in more detail below with reference to the accompanying drawings. Figure 1 shows a schematic longitudinal cross-sectional view of a filling pipe of a device according to an example of the present invention;

[0029] Fig. 2 is a schematic cross-sectional view transverse to the longitudinal direction of the filling pipe of the device shown in Fig. 1;

[0030] Fig. 3 is a schematic plan view of the device of Fig. 1;

[0031] Fig. 4 is a schematic cross-sectional view transverse to the longitudinal direction of the filling pipe to illustrate liquid flows without guide elements;

[0032] Fig. 5 is a schematic cross-sectional view transverse to the longitudinal direction of the filling pipe to illustrate liquid flows with guide elements;

[0033] Fig. 6 is a schematic plan view of the example of the device shown in Fig. 5; and

[0034] Fig. 7-10 are schematic representations of a device which does not fall within the scope of the claims, but whose explanation serves to understand the present invention.

[0035] Detailed description

[0036] Examples of the present invention are described in detail below with the use of the accompanying drawings. It should be noted that like elements or elements having the same functionality are provided with the same or similar reference numerals, and repeated descriptions of elements provided with the same or similar reference numerals are typically omitted. Descriptions of elements having the same or similar reference numerals may be interchangeable. In the following description, many details are described to provide a more thorough explanation of examples of the invention. However, it will be obvious to those skilled in the art that other examples may be implemented without these specific details.Features of the different examples described may be combined with each other unless features of a corresponding combination are mutually exclusive or such a combination is expressly excluded.

[0037] Before discussing examples of the present invention in more detail, an apparatus for treating wafers with a treatment liquid, on which the invention is based, will first be explained with reference to Figs. 7 to 10. The apparatus may have a structure similar to that described in the above-mentioned TW 202003124 A.

[0038] Fig. 7 shows a schematic cross-sectional view along a longitudinal direction of a filling tube, and Fig. 8 shows a schematic cross-sectional view transverse to the longitudinal direction of the filling tube. Fig. 9 shows a schematic plan view of the device, and Fig. 10 shows a schematic cross-sectional view corresponding to Fig. 7, in which fluid flows are indicated by arrows.

[0039] The device is designed for treating wafers in batch processing using wafer carriers. The device has a basin 10 for holding a treatment liquid, which can also be referred to as a treatment medium. The treatment liquid can be, for example, an etching medium or a cleaning medium. The basin 10 has side walls 12 which, in the example shown, in which the basin is rectangular, delimit four sides of the basin. In other examples, the basin can have a different shape, for example an oval shape or a different number of corners. The basin 10 further has a base 14 which delimits the basin at the bottom. The basin 10 can be open at the top. A perforated plate 16 is provided in the basin 10 and divides the basin into an upper region 18 and a lower region 20. The upper region 18 is designed to accommodate one or more wafer carriers 22.The height of the side walls 12 of the basin 10 is greater than the height of the wafer carrier(s) 22. Although the wafer carrier 22 is shown spaced from the perforated plate 16 in the figures, the wafer carrier 22 can rest on the perforated plate 16. In examples, holders can be provided on the perforated plate 16, on which the wafer carrier 22 rests. The perforated plate 16 has holes 24 that fluidically connect the lower region 20 of the basin 10 with the upper region 18 of the basin 10. A filling pipe 26 is arranged in the lower region 20 of the basin 10. The filling pipe 26 has filling pipe openings 28 along its longitudinal direction. The filling pipe openings 28 can be oriented towards the underside of the basin to enable a more even distribution of the treatment liquid. In other examples, the filling pipe openings may be directed obliquely upwards, for example at any angle.In a longitudinally central region thereof, the filling pipe 26 is fluidically coupled to a treatment fluid supply line 30. The treatment fluid supply line 30 is further fluidically coupled to a pump 32.

[0040] As can best be seen in Fig. 9, the holes 24 in the perforated plate 16 are distributed over the area that forms one or more receiving areas for wafer carriers 22.

[0041] The wafer carrier 22 has, as can be seen in Fig. 9, a rectangular shape in plan view. The wafer carrier 22 has rods 40 extending in the longitudinal direction thereof, on which a plurality of wafers 42 rest next to one another, as can best be seen in Fig. 7. The rods 40 can be designed to hold the wafers 42 next to one another at a defined distance from one another. As can be best seen in Fig. 8, the wafers 42 can rest on two rods 40 on the underside and be held on each of the two sides by two rods 40. At the two longitudinal ends, the wafer carrier 22 has end plates 44 to which the rods 40 are fastened and which hold the rods 40 in position relative to one another. The wafer carrier 22 thus has openings between the rods which allow a treatment liquid to flow over the wafers held therein.Corresponding wafer carriers are known and require no further discussion herein. The devices described herein are suitable for treating wafers held by wafer carriers that allow a treatment liquid to flow over the held wafers from an underside of the wafer carrier. It will be clear to those skilled in the art that the wafer carrier may differ from the wafer carrier described herein as long as it allows a treatment liquid to flow over the held wafers. For example, the wafer carrier could have a different number of rods than shown here. In other examples, the openings that allow the treatment liquid to flow over the wafers may be formed by a grid of the wafer carrier or the like. Such wafer carriers are also commonly referred to as carriers or carriers.In the example shown, the upper region 18 of the basin 10 has receiving areas for two wafer carriers 22, specifically in such a way that the longitudinal direction of the wafer carriers 22 is parallel to the longitudinal direction of the filling tube 26. As can be seen in Fig. 9, the filling tube openings 28 can be elongated in the longitudinal direction of the filling tube 26. In other examples, the filling tube openings can have other shapes, for example round or elongated transversely to the longitudinal direction of the filling tube. In yet other examples, several filling tube openings could be provided next to one another, each transversely to the longitudinal direction of the filling tube. In further examples, the filling tube openings can have different shapes. In further examples, the filling tube openings can have different opening sizes.

[0042] During operation, the pump 32 pumps treatment fluid through the treatment fluid supply line 30 into the filling pipe 26, as indicated by an arrow P1 in Fig. 10. The fluid splits into two streams, which flow into the respective sections of the filling pipe 26 on either side of the treatment fluid supply line 30, as indicated by arrows P2 in Fig. 10. The fluid flowing through the filling pipe 26 leaves the filling pipe through the filling pipe openings 28, which in the example shown are directed towards the bottom 14 of the basin. This creates the flows indicated by arrows in Fig. 10 through the filling pipe openings 28. The flows are deflected at the bottom 14 of the basin 10 and pass upwards past the filling pipe 26. There, the treatment liquid flows through the holes 24 in the perforated plate and flows through the wafer carrier 22.As a result, the wafers 42 arranged in the wafer carrier 22 are treated with the treatment fluid. If the basin is filled with treatment fluid, the treatment fluid can exit, for example, via the upper edge of the basin or a designated drain. In some examples, the treatment fluid that has left the basin can be recirculated via the treatment fluid supply line 30 via a fluid circuit, for example, after treatment.

[0043] However, the inventors have recognized that a flow occurs in the lower region 20 of the basin 10 in the longitudinal direction of the filling pipe, which results in the upward flow being significantly higher in the edge regions of the basin 10 than in the central regions of the basin 10, as indicated by corresponding arrows P3 of different widths in Fig. 10. However, this flow distribution results in the wafers 42 arranged in the wafer carrier 22 not being evenly flowed around by the treatment liquid, so that the wafers are not treated evenly. Although in the example described the device is designed to accommodate two wafer carriers, in other examples the device can be designed for a different number of wafer carriers, for example an arrangement of four wafer carriers next to one another, a 2x2 arrangement of four wafer carriers, an arrangement of 2x3 wafer carriers, or even just one wafer carrier.Although only one filling pipe is provided in the example shown, in other examples a filling pipe could be provided for each wafer carrier, i.e. for each receiving area of ​​a wafer carrier.

[0044] In examples, the holes 24 of the perforated plate 16 are provided in a uniform, two-dimensional pattern. In examples, the holes may be the same size. In examples, the holes may be different sizes.

[0045] It goes without saying that the components of the device are made of suitable materials that are resistant to the treatment liquids or treatment media with which the wafers are to be treated. In examples, the respective components may be made of suitable metal materials or plastic materials.

[0046] Examples of the present invention will now be explained in more detail with reference to Figs. 1 to 6. The details explained above with reference to Figs. 7 to 10 apply equally to the examples of the present invention and will not be repeated again.

[0047] As shown in Fig. 1, the device comprises the basin 10 for holding the treatment liquid and the wafers 42 to be treated, and the perforated plate 16, which divides the basin 10 into the upper region 18 and the lower region 20. The perforated plate has the holes 24 that fluidly connect the lower region 20 and the upper region 18. The filling pipe 26 is arranged in the lower region 20 of the basin 10 and has the filling pipe openings 28 along its longitudinal direction (from left to right in Fig. 1), which in the example shown are directed towards an underside of the basin, i.e., the bottom 14. Furthermore, separating elements 50 are provided in the lower region 20 of the basin, only some of which are provided with the reference numeral 50. The separating elements can be located on the bottom 14 of the basin, as shown in Fig. 2, wherein in Fig.2, a slight distance is shown between the separating element 50 and the pool floor 14 for the purpose of illustration. At this point it should be noted that the number of separating elements differs in Figs. 1 and 3, although this is merely for illustration purposes. In the example shown, the separating elements extend in the transverse direction (perpendicular to the longitudinal direction of the filling pipe 26) at least over the area of ​​the perforated plate 16 in which the holes 24 are provided. As indicated in Fig. 3, the perforated plates can also extend laterally beyond this area, for example to the side walls of the pool, top and bottom in Fig. 3. In examples, the separating elements are plate-shaped. In examples, the separating elements extend at least in a central area from the bottom 14 of the pool 10 to the perforated plate 16, as best shown in Fig. 2.In outer edge regions, the separating elements 50 may be spaced from the bottom of the basin, particularly if the bottom rises in the outer edge regions, as shown in Fig. 2.

[0048] The separating elements 50 preferably extend in a direction perpendicular to the longitudinal direction of the filling pipe 26. In other examples, the separating elements could also extend at a slight angle to this direction, for example at an angle < 10 °.

[0049] In some examples, a separator 50 is provided between each adjacent pair of fill tube openings. In other examples, a smaller number of separators could be provided, for example, two fill tube openings could be provided between each pair of separators. In other examples, the separators could be provided irregularly, with the spacing between separators being larger in a central region and smaller in an outer region.

[0050] The separating elements 50, which are arranged below the perforated plate 16, i.e., below the wafer carrier plane, divide the lower region 20 into compartments that segment the flow from the filling tube. In some examples, the compartments are in the form of sections running perpendicular to the longitudinal direction of the filling tube 26. Such flow segmentation cannot be achieved with a simple filling tube.

[0051] In examples, the dividing elements can extend to the bottom of the tank at the bottom, to the perforated plate at the top, and to the sides at least to the end of the area in which the holes in the perforated plate are arranged. As a result, flows in the longitudinal direction of the filling pipe past the dividing elements in this area can be completely prevented. In other examples, the upper and lower ends of the dividing elements can be at a distance from the perforated plate and the bottom of the tank, respectively. In examples, the dividing elements can be attached to the filling pipe. In examples, the dividing elements can be attached to the perforated plate and have a recess below the filling pipe that allows the dividing elements to be pushed over the filling pipe from above. In examples, the dividing elements can be attached to the bottom and have a recess above the filling pipe so that the filling pipe can be inserted from above.Such a design of the separating elements with a recess can simplify assembly without significantly affecting functionality.

[0052] In some examples, the filling tube openings 28 may be elongated in the longitudinal direction of the filling tube. In some examples, the filling tube openings 28 may have an extension in the longitudinal direction of the filling tube that essentially corresponds to the distance between two separating elements 50, thereby enabling a more homogeneous distribution into the respective compartment.

[0053] The partition walls reduce the flow of treatment liquid in the longitudinal direction of the filling pipe 26 between the filling pipe openings 28, between which the partition walls 50 are arranged. This creates a circular flow P4 in the respective compartments, as shown in Fig. 1. This circular flow P4 results in a more uniform liquid flow through the openings 24 of the perforated plate 16, as indicated by arrows P5 in Fig. 1.

[0054] The separating elements, designed in the form of webs, thus create a segmentation along the filling tube, which can reduce differences in the flow through the holes 24 of the perforated plate 16 in the longitudinal direction of the filling tube 26. As a result, the treatment liquid flows more evenly through the wafer carrier(s) 22 arranged in the upper region 18 of the tank 10. This allows for a more uniform treatment of the wafers 42 arranged in the wafer carriers 22, through which the liquid flows from bottom to top.

[0055] In addition to homogenizing the flow through the holes 24 of the perforated plate, the separating elements 50 can also have a supporting effect for the perforated plate 16 and the filling pipe 26, so that the stability of the basin and thus the basin statics can be improved. Fig. 4 shows a schematic cross-sectional view that essentially corresponds to the view shown in Fig. 2, wherein liquid flows in the upper region 18 of the basin 10 are represented by arrows P6. The liquid flow tends to choose the path with the lowest fluidic resistance and flow past the wafer carriers 22, so that a large portion of the liquid flows past the outside of the wafer carriers, a portion of the liquid flows between the two wafer carriers shown, and only a small portion of the liquid flow actually passes between the wafers 42 through the wafer carriers 22.

[0056] To prevent this and to achieve a stronger and more homogeneous flow through the wafer carriers 22 and thus the wafers 42 arranged in the wafer carriers 22, in examples of the invention, guide elements are provided in addition to the outer walls of the basin 10, which are arranged in the upper region 18 of the basin 10. Corresponding guide elements 60, 62 and 64 are shown in Fig. 5. The guide elements 60, 62 and 64 are arranged above the perforated plate 16 and can be fastened thereto. The guide element 60 delimits a first receiving area for a wafer carrier at the outer edge, the guide element 64 delimits a second receiving area for a wafer carrier at an outer edge, and the guide element 62 delimits the two receiving areas at the inner edge thereof.

[0057] As shown in Fig. 6, the guide elements 60, 62 and 64 extend along the longitudinal extent of the wafer carriers 22. The guide elements 60, 62 and 64 extend upward in a direction perpendicular to the perforated plate 16 and can serve to position the wafer carriers 22 in the upper region 18 of the basin 10. The distance between the guide elements 60 and 62 and the distance between the guide elements 62 and 64 can correspond to a dimension of the wafer carriers 22 in a direction perpendicular to the longitudinal direction of the filling tube 26. More precisely, in the example shown, this distance corresponds to the width of the wafer carrier in the region of the outer holding rods 40. As can be seen in Fig. 6, the side plates 44 of the wafer carrier 22 protrude laterally beyond the rods 40 in the example shown. The length of the guide elements in the longitudinal direction of the filling tube 26 corresponds to a distance between these end plates of the wafer carrier 44.Thus, in this example, the wafer carrier can be positioned both in the longitudinal direction of the filling tube and in the transverse direction thereof. In other examples, the distance between the respective guide elements in the transverse direction could also correspond to the width of the end plates 44. In some examples, the side plates 44 do not protrude laterally beyond the rods 40, so that the distance between the respective guide elements corresponds both to the width in the area of ​​the rods and to the width of the end plates.

[0058] In some examples, the sides of the guide elements facing the receiving areas are full-surface and extend over the entire height of the receiving areas, i.e., the wafer carriers. This makes it possible to concentrate the flow over the entire height of the wafers accommodated in the wafer carriers.

[0059] The definition that the distance between the guide elements transverse to the longitudinal direction of the filling tube corresponds to a dimension of the wafer carrier transverse to the longitudinal direction of the filling tube means that this distance is slightly larger than the corresponding dimension to allow the wafer carrier to be positioned between the guide elements. The same applies to the definition that the length of the guide elements in the longitudinal direction of the filling tube corresponds to a distance between the end plates of the wafer carrier, which means that the distance between the end plates of the wafer carrier is slightly larger than the length of the guide elements in the longitudinal direction to allow the guide elements to be positioned between the end plates.

[0060] The lateral guide elements thus provide narrowly defined channels for the wafer carriers, allowing the flow of treatment medium through the perforated plate to be concentrated onto the wafer carriers. It should be noted that the wafers should generally not be positioned too close to the holes 24 of the perforated plate 16 to avoid overtreatment of the wafers at the points closest to the holes. To achieve this, the end plates 44 can project downwards beyond the lower rods 40. Alternatively, holders can be provided in the tank 10, onto which the wafer carriers are placed in the tank.

[0061] In Fig. 5, arrows P7 show how the liquid flow is concentrated through the wafer carriers 22 due to the guide elements 60, 62, and 64. Thus, examples of the present invention enable concentrated and uniform treatment of the wafers 42 arranged in the wafer carriers 22 with a treatment medium flowing through the holes 24 in the perforated plate 16. Although in the example shown the basin 10 has only two receiving areas for wafer carriers 22, in other examples, as explained above, the basin can have a different number of receiving areas. Corresponding guide elements for the wafer carriers can be provided for each of the receiving areas. The guide elements can be provided in the form of walls in the upper area 18 of the basin 10. The guide elements do not have to extend beyond the upper edge of the wafer carriers 22, as shown in Fig. 5.In alternative examples, some or all of the guide elements may have a lower height. In yet alternative examples, no guide element is provided between two wafer carriers, for example, if the receiving areas of the two wafer carriers are directly adjacent to one another or are arranged very close to one another. In some examples, a guide element arranged between two wafer carriers may have a lower height than outer guide elements.

[0062] The guide elements thus enable targeted media guidance through the wafer carriers and a homogeneous flow through them. This allows the treatment medium to be used more effectively, for example, during etching processes or wafer cleaning. In addition to concentrating the medium through the wafer carriers, the guide elements also enable the wafer carriers to be positioned in the tank, eliminating the need for additional wafer carrier centering.

[0063] In corresponding methods for treating wafers, treatment liquid is pumped into the filling pipe 26 and through the filling pipe openings 28 by the pump 32 (shown in Fig. 7), which is fluidically coupled to the treatment liquid supply line 30, thereby causing flows P5 of the treatment liquid through the holes 24 in the perforated plate 16 into the upper region 18 of the tank. These flows P5 can be homogenized due to the compartments formed by the separating elements 50, compared to highly inhomogeneous flows that would occur without the separating elements, see flows P3 in Fig. 10. These flows P5 allow wafers 42 in a wafer carrier 22, which was previously introduced into the upper region 18 of the tank 10, to be treated evenly with the treatment liquid.Furthermore, in examples, the guide elements can be used to concentrate the flows through the wafer carriers and further homogenize the flow through them.

[0064] Examples of the present invention may relate in particular to the treatment of semiconductor wafers in baskets in batch processing, wherein the treatment may consist, for example, of etching the wafer surfaces or cleaning the wafer surfaces. Corresponding treatment fluids for semiconductor wafers, for example, silicon wafers, are known to those skilled in the art and require no further explanation here.

[0065] Although features of the invention have been described in each case with reference to device features or method features, it is obvious to those skilled in the art that corresponding features can also be part of a method or device. Thus, the device can be configured to perform corresponding method steps, and the respective functionality of the device can represent corresponding method steps.

[0066] In the foregoing Detailed Description, various features have been grouped together in examples in order to streamline the disclosure. This manner of disclosure should not be interpreted as intending that the claimed examples include more features than are expressly recited in each claim. Rather, as the following claims reflect, the subject matter may lie in fewer than all of the features of a single disclosed example. Accordingly, the following claims are hereby incorporated into the Detailed Description, with each claim being capable of standing as its own separate example.While each claim may stand as its own separate example, it should be noted that although dependent claims in the claims refer to a specific combination with one or more other claims, other examples also include a combination of dependent claims with the subject matter of any other dependent claim or a combination of any feature with other dependent or independent claims. Such combinations are intended to be encompassed unless it is stated that a specific combination is not intended. Furthermore, it is intended to encompass a combination of features of a claim with any other independent claim, even if that claim is not directly dependent on the independent claim.

[0067] The examples described above are merely illustrative of the principles of the present invention. It is understood that modifications and variations of the arrangements and details described will be apparent to those skilled in the art. Therefore, it is intended that the invention be limited only by the appended claims and not by the specific details set forth for the purpose of describing and explaining the examples.

Claims

Claims 1. A device for treating wafers (42) with a treatment liquid, comprising: a basin (10) for receiving the treatment liquid and the wafers (42) to be treated; a perforated plate (16) which separates the basin (10) into an upper region (18) and a lower region (20), wherein the perforated plate (16) has holes (24) which fluidically connect the lower region (20) and the upper region (18); and a filling pipe (26) which is arranged in the lower region (20) of the basin (10) and has filling pipe openings (28) along its longitudinal direction, characterized by Separating elements (50) in the lower region (20) of the basin (10), which are arranged between at least some filling pipe openings (28) of the filling pipe (26) and extend in a direction that intersects the longitudinal direction of the filling pipe (26) in order to at least reduce flows of the treatment liquid in the longitudinal direction of the filling pipe (26) between the at least some of the filling pipe openings (28).

2. Device according to claim 1, wherein the dividing elements (50) are designed to divide the lower region (20) of the basin (10) into compartments which extend laterally outwards from the filling pipe (26).

3. Device according to claim 1 or 2, wherein a separating element (50) is provided between each adjacent pair of filling pipe openings (28), or wherein two or more filling pipe openings (28) are provided between each two separating elements (50).

4. Device according to one of claims 1 to 3, wherein the separating elements (50) extend in the direction intersecting the longitudinal direction of the filling pipe (26) over a region of the perforated plate (16) in which the holes (24) are provided.

5. Device according to one of claims 1 to 4, wherein the direction in which the separating elements (50) extend is perpendicular to the longitudinal direction of the filling pipe (26).

6. Device according to one of claims 1 to 5, wherein the filling pipe (26) is fluidically coupled to a treatment liquid supply line (30) in a central region thereof in the longitudinal direction.

7. Device according to one of claims 1 to 6, wherein the upper region (18) of the basin (10) has a receiving region for one or more wafer carriers (22), in each of which wafers (42) are arranged next to one another with a distance between them.

8. Device according to claim 7, wherein the upper region (18) has a plurality of receiving regions in order to receive a plurality of wafer carriers (22) next to one another in the longitudinal direction of the filling tube (26) and / or transversely to the longitudinal direction of the filling tube (26).

9. Device according to one of claims 7 or 8, wherein the holes (24) in the perforated plate (16) are distributed at least over the receiving area(s).

10. Apparatus according to one of claims 7 to 9, further comprising guide elements (60, 62, 64) in addition to outer walls (12) of the basin (10), which are arranged in the upper region (18) of the basin (10) and which laterally delimit the receiving region of at least one wafer carrier (22) in order to concentrate a flow of the treatment liquid on the receiving region.

11. Device according to claim 10, wherein the guide elements (60, 62, 64) delimit the receiving area of ​​the at least one wafer carrier (22) on two sides which extend parallel to the longitudinal extent of the filling tube (26).

12. Device according to claim 10 or 11, wherein the guide elements (60, 62, 64) are designed to position the at least one wafer carrier (22) in the basin (10).

13. Device according to claim 12, wherein a distance between the guide elements (60, 62, 64) transverse to the longitudinal direction of the filling tube (26) corresponds to a dimension of the wafer carrier (22) transverse to the longitudinal direction of the filling tube (26).

14. Device according to claim 12 or 13, wherein a length of the guide elements (60, 62, 64) in the longitudinal direction of the filling tube (26) corresponds to a distance between end plates of the wafer carrier (22).

15. Device according to one of claims 10 to 14, which has a plurality of corresponding guide elements (60, 62, 64) which laterally delimit receiving areas for a plurality of wafer carriers (22) in the upper region (18) of the basin (10).

16. Device according to claim 15, wherein the guide elements (60, 62, 64) have at least one guide element (62) which delimits mutually facing sides of two adjacent receiving areas.

17. Device according to one of claims 1 to 16, which comprises a pump for pumping the treatment liquid into the filling tube (26) and through the filling tube openings (28).

18. A method for treating wafers (42) with a treatment liquid using an apparatus according to claim 17, having the following features: introducing at least one wafer carrier (22) into the upper region (18) of the basin (10); Pumping the treatment liquid by means of the pump into the filling tube (26) and through the filling tube openings (28), thereby causing flows of the treatment liquid through the holes (24) in the perforated plate (16) into the upper region (18) of the basin (10) in order to treat wafers (42) in the wafer carrier (22) with the treatment liquid, wherein the separating elements (50) at least reduce flows of the treatment liquid in the longitudinal direction of the filling tube (26) between at least some of the filling tube openings (28) and thereby reduce differences between flows of the treatment liquid through holes (24) in the perforated plate (16) arranged in the longitudinal direction of the filling tube (26).

19. Method according to claim 18 using a device according to one of claims 10 to 16, wherein the guide elements (60, 62, 64) are used as a guide when introducing the at least one wafer carrier (22) into the upper region (18) of the basin (10).

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