Device and method for treating wafers using separating elements

Abstract

Device for treating wafers (42) with a treatment fluid, having the following features: a basin (10) for receiving the treatment fluid and the wafers (42) to be treated; a perforated plate (16) that separates the basin (10) into an upper area (18) and a lower area (20), wherein the perforated plate (16) has holes (24) that fluidically connect the lower area (20) and the upper area (18); a filling pipe (26) which is arranged in the lower area (20) of the basin (10) and has filling pipe openings (28) along its longitudinal direction, and 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 fluid in the longitudinal direction of the filling pipe (26) between the at least some of the filling pipe openings (28), where the filling pipe (26) is fluidically coupled in a longitudinally central area of ​​the same with a treatment fluid supply line (30) through which treatment fluid can be pumped into the filling pipe (26), and the filling pipe openings (28) are aligned towards the underside of the basin (10).

Description

[0001] 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 fluid.

[0002] Various methods for treating wafers with liquids are known from the prior art. For example, EP 0 762 482 B1 describes devices and methods for etching wafers in which a wafer carrier is arranged in a tank. The tank has a side wall with holes through which treatment fluid is supplied from one side. The treatment fluid flows through the etching tank in such a way that a surface horizontal laminar flow is formed in the vicinity of the liquid's surface, and a rotating flow, essentially concentric to the center of each wafer, is created in the vicinity of the semiconductor wafers.

[0003] TW 202003124 A describes a device for cleaning wafers in a batch process, in which a wafer carrier is placed in a basin. A perforated plate with a plurality of uniformly arranged openings is provided in a lower section of the basin. Pipes are provided below the perforated plate, having openings directed towards a lower wall of the basin, so that liquid can be pumped through the pipe openings, then through the perforated plate and past the wafers to clean them. It is described that during rinsing, the wafers are first rinsed from bottom to top and then from top to bottom. Further state of the art can be found in US 2003 / 0 116 178 A1, US 2019 / 0 055 665 A1, US 2010 / 0 031 983 A1, US 2006 / 0 037 698 A1, US 2015 / 0 197 861 A1 and US 2012 / 0 305 033 A1.

[0004] A problem with known processes is that achieving uniform treatment of the wafers is difficult in batch processing. The treatment intensity, for example, the etching rate, can depend on the flow caused by circulation of the treatment medium, on varying homogeneity of the treatment medium across the bath's surface, within the wafer carrier, or between different wafer carriers within a bath. Particularly with a larger number of wafer carriers in a batch, for example, six or eight wafer carriers, the flow through the wafer carriers in the bath can be asymmetrical, with the flow through the middle baskets differing from that through the outer baskets. In a batch with eight baskets, the flow at the bath surface can run towards the side wall of the bath, where lateral overflow can occur.

[0005] To solve these problems, one possibility is to guide the flow by designing a perforated plate below or to the side of the wafer carriers, as described in the aforementioned publications. Inlet tubes could be designed below the wafer carriers to locally modify the flow. Furthermore, diffuse media distribution via gas bubbles could be used in addition to circulation.

[0006] The object of the present invention is to provide devices and methods for the uniform treatment of wafers in a wafer carrier with a treatment fluid.

[0007] This problem is solved by a device for treating wafers according to claim 1 and a method for treating wafers according to claim 18.

[0008] Examples include a device for treating wafers with a treatment fluid, with the following features: a basin for receiving the treatment fluid and the wafers to be treated; a perforated plate that divides the basin into an upper area and a lower area, wherein the perforated plate has holes that fluidically connect the lower area and the upper area; and a filling pipe which is located in the lower part of the basin and has filling pipe openings along its longitudinal direction, characterized by Separating elements in the lower part of the basin, which are arranged between at least some of the filling pipe openings and extend in a direction that intersects the longitudinal direction of the filling pipe, in order to at least reduce flows of the treatment fluid in the longitudinal direction of the filling pipe between at least some of the filling pipe openings.

[0009] 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, thus achieving a more uniform flow through one or more wafer carriers arranged above the perforated plate. This allows for more uniform treatment of the wafers with the treatment fluid, which can also be referred to as the treatment medium. Furthermore, this enables more efficient use of the medium. The treatment fluid can be, for example, cleaning fluids or etching fluids commonly used for treating silicon wafers.

[0010] In some examples, the separating elements are designed to divide the lower part of the basin into compartments that extend laterally outwards from the filling pipe. This division makes it possible to limit the longitudinal flow of the treatment fluid to the respective compartments, thereby creating a circular flow within each compartment and ensuring effective, uniform flow through the perforated plate located above.

[0011] In some examples, the filling pipe openings are oriented towards the underside of the basin. In others, a separating element is provided between each adjacent pair of filling pipe openings. This allows for a significant reduction or suppression of flow of the treatment fluid along the length of the filling pipe.

[0012] In some examples, the separating elements extend in the direction that intersects the longitudinal direction of the filling tube over a portion of the perforated plate where the holes are located. This makes it possible to reduce or suppress the flow of the treatment fluid longitudinally along the filling tube over the entire area of ​​the perforated plate where the holes are located transversely. This allows for a uniform flow above this entire area, over which one or more wafer carriers may be positioned.

[0013] In these examples, the direction in which the separating elements extend is perpendicular to the longitudinal direction of the filling pipe. The direction in which the separating elements extend refers to the direction of their longest dimension, and the separating elements may have an elongated, plate-like shape. These examples thus effectively enable the treatment fluid to flow perpendicular to the longitudinal direction of the filling pipe, ensuring a uniform flow of the treatment fluid above the perforated plate.

[0014] In some examples, the filling pipe is fluidically coupled to a treatment fluid supply line in a longitudinally central area of ​​the same, so that a uniform flow of the treatment fluid through the filling pipe from the treatment fluid supply line can be achieved.

[0015] In some examples, the upper part of the basin has a receiving area for one or more wafer carriers, in which wafers are arranged side by side with a gap between them. In others, the upper part has multiple receiving areas to accommodate several wafer carriers side by side, either longitudinally along 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 ensure a uniform flow through the wafer carriers in the receiving area(s).

[0016] In some examples, guide elements are arranged in the upper region of the basin in addition to the outer walls. These guide elements laterally delimit the receiving area of ​​at least one wafer carrier to concentrate the flow of the treatment fluid onto this area. "Laterally" here refers to the lateral direction of the filling tube. The guide elements can be elements adjacent to the wafer carriers, separating them and forcing the flow through the wafer carriers and thus to the wafer surfaces (i.e., the wafer sides), preventing lateral flow deviation. Therefore, the guide elements enable targeted guidance of the treatment fluid through the wafer carriers and thus ensure a homogeneous flow. The guide elements can thus further improve the homogenization of the treatment with a treatment fluid.

[0017] In some examples, the guide elements limit the receiving area of ​​at least one wafer carrier to two sides that extend parallel to the longitudinal extent of the filling tube. Typically, the dimensions of the wafer carriers along the longitudinal direction of the filling tube are larger than those in the perpendicular direction, i.e., the transverse direction. Thus, these examples allow the flow to be concentrated onto the receiving area along both longer sides of the wafer carrier.

[0018] In the examples, the guide elements are further designed to position at least one wafer carrier in the basin. Thus, the examples enable precise positioning of the wafer carrier(s) in the basin at a defined position above the perforated plate.

[0019] In some examples, the distance between the guide elements perpendicular to the longitudinal direction of the filling tube can correspond to a dimension of the wafer carrier perpendicular to the longitudinal direction of the filling tube. This allows for precise positioning of the wafer carrier(s) and also prevents liquid from flowing laterally past the wafer carrier(s).

[0020] In some examples, the guide elements are designed to position wafer carriers that have end plates spaced apart along the length of the filling tube. In such examples, the length of the guide elements along the length of the filling tube can correspond to the distance between these end plates of the wafer carrier. Thus, such examples also enable precise positioning of the wafer carrier(s) along the length of the filling tube.

[0021] In some examples, a plurality of corresponding guide elements can be provided, which laterally define the 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 in defined positions in the upper area of ​​the basin. At least one of the guide elements can be designed to be positioned between two adjacent receiving areas and thus define the opposing sides of the two adjacent receiving areas.

[0022] In some examples, the device further includes a pump to pump the treatment fluid into the filling tube and through the filling tube openings. In these examples, the fluid is pumped through the filling tube openings towards the bottom of the basin, where it can be distributed transversely in the lower area of ​​the basin and pass through the perforated plate into the upper area of ​​the basin.

[0023] Examples describe a method for treating wafers with a treatment fluid using one of the devices described herein. At least one wafer carrier is placed in the upper part of the basin. Treatment fluid is pumped into the filling tube and through the filling tube openings, for example, towards the bottom of the basin. This causes the treatment fluid to flow through the holes in the perforated plate into the upper part of the basin, thus treating wafers in the wafer carrier with the treatment fluid. The separating elements reduce the longitudinal flow of the treatment fluid between at least some of the filling tube openings, thereby minimizing differences in the flow of treatment fluid through the longitudinally oriented holes in the perforated plate.This allows for a more uniform flow through the wafers in the wafer tray, as described above. This effect can also be achieved for multiple wafer trays if the upper area of ​​the basin is designed to provide multiple receiving areas for several wafer trays.

[0024] In examples of this method, the described guide elements can be used as a guide when inserting at least one wafer carrier into the upper area 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. Brief description of the drawings

[0025] Examples of the invention are explained in more detail below with reference to the accompanying drawings. These show: Fig. 1 a schematic cross-sectional view in longitudinal direction of a filling tube of a device according to an example of the present invention; Fig. 2 a schematic cross-sectional view transverse to the longitudinal direction of the filling pipe of the in Fig. 1 device shown; Fig. 3 a schematic top view of the device of Fig. 1; Fig. 4 A schematic cross-sectional view perpendicular to the longitudinal direction of the filling tube to illustrate liquid flows without guide elements; Fig. 5 a schematic cross-sectional view transverse to the longitudinal direction of the filling tube to illustrate liquid flows with guide elements; Fig. 6 a schematic top view of the in Fig. 5. Example of the device shown; and Fig. 7-10 schematic representations of a device which is not covered by the scope of the claims, but whose explanation serves to help understand the present invention. Detailed description

[0026] Examples of the present invention are described in detail below with reference to the accompanying drawings. It should be noted that identical elements or elements having the same functionality are designated with the same or similar reference numerals, and repeated descriptions of elements with the same or similar reference numerals are typically omitted. Descriptions of elements with the same or similar reference numerals may be interchangeable. Many details are described in the following description to provide a more thorough explanation of examples of the invention. However, it is obvious to those skilled in the art that other examples can be implemented without these specific details.Features of the different described examples can be combined with each other, unless features of a corresponding combination are mutually exclusive or such a combination is expressly excluded.

[0027] Before discussing examples of the present invention in more detail, reference will first be made to the Fig. 7, Fig. 8, Fig. 9 to Fig. 10 describes a device for treating wafers with a treatment fluid, from which the invention is based. The device can have a structure similar to that described in the above-mentioned TW 202003124 A.

[0028] Fig. Figure 7 shows a schematic cross-sectional view along a longitudinal direction of a filling pipe and Fig. 8 A schematic cross-sectional view perpendicular to the longitudinal direction of the filling pipe. Fig. Figure 9 shows a schematic top view of the device and Fig. 10 a schematic cross-sectional view accordingly Fig. 7, in which fluid flows are indicated by arrows.

[0029] The device is designed for batch processing of wafers using wafer carriers. The device includes a basin 10 for holding a treatment fluid, which can also be referred to as a treatment medium. The treatment fluid can be, for example, an etching medium or a cleaning medium. The basin 10 has side walls 12, which, in the example shown where the basin is rectangular, define four sides of the basin. In other examples, the basin can have a different shape, such as an oval shape, or a different number of corners. The basin 10 also has a bottom 14, which defines the basin's lower boundary. 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 section 18 and a lower section 20. The upper section 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 apart from the perforated plate 16 in the figures, it can also rest on the perforated plate 16. In some examples, supports may be provided on the perforated plate 16 upon 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.

[0030] 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 allow for a more uniform distribution of the treatment fluid. In other examples, the filling pipe openings can be directed obliquely upwards, for example at any desired angle. In a longitudinally central region of the basin, 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.

[0031] As in Fig. As can be seen best in Figure 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.

[0032] The wafer carrier 22 shows, as in Fig. As can be seen in Figure 9, the wafer carrier 22 has a rectangular shape in plan view. It has longitudinally extending rods 40 on which a plurality of wafers 42 rest side by side, as is best seen in Figure 9. Fig. 7 can be seen. The rods 40 can be designed to hold the wafers 42 side by side at a defined distance from each other. As shown in Fig. As can be best seen in Figure 8, the wafers 42 rest on two rods 40 on their underside and are held on both sides by two rods 40 each. At both longitudinal ends, the wafer carrier 22 has end plates 44 to which the rods 40 are attached, holding them in position relative to each other. The wafer carrier 22 thus has openings between the rods, allowing a treatment fluid to flow over the wafers held therein. Such wafer carriers are known and do not require further discussion here. The devices described herein are suitable for treating wafers held by wafer carriers that allow a treatment fluid to flow over the held wafers from an underside of the wafer carrier.It is clear to experts that the wafer support may differ from the one described herein, as long as it allows the held wafers to be overflowed with a treatment fluid. For example, the wafer support could have a different number of bars than shown here. In other examples, the openings that allow the wafers to be overflowed with the treatment fluid may be formed by a grid of the wafer support or the like. Such wafer supports are also commonly referred to as carriers or frames.

[0033] In the example shown, the upper region 18 of the basin 10 has receiving areas for two wafer carriers 22, such that the longitudinal direction of the wafer carriers 22 is parallel to the longitudinal direction of the filling tube 26. As shown in Fig. As can be seen in Figure 9, the filling pipe openings 28 can be elongated in the longitudinal direction of the filling pipe 26. In other examples, the filling pipe openings can have other shapes, for example, round or elongated perpendicular to the longitudinal direction of the filling pipe. In still other examples, several filling pipe openings could be provided side by side, each perpendicular to the longitudinal direction of the filling pipe. In further examples, the filling pipe openings can have different shapes. In still other examples, the filling pipe openings can have different opening sizes.

[0034] During operation, treatment fluid is pumped by pump 32 through the treatment fluid supply line 30 into the filling pipe 26, as indicated by arrow P1. Fig. 10. The liquid splits into two streams, which flow into the respective sections of the filling pipe 26 on both sides of the treatment liquid supply line 30, as indicated by arrows P2 in Fig. 10 is indicated. The liquid flowing through the filling pipe 26 leaves the filling pipe through the filling pipe openings 28, which in the example shown are oriented towards the bottom 14 of the basin. This creates the [unclear - possibly referring to a specific feature or feature]. Fig. The ten flows through the filling pipe openings 28 are indicated by arrows. The flows are deflected at the bottom 14 of the basin 10 and pass the filling pipe 26 upwards. There, the treatment fluid flows through the holes 24 in the perforated plate and through the wafer carrier 22. This treats the wafers 42 arranged in the wafer carrier 22 with the treatment fluid. Once 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 cases, the treatment fluid that has left the basin can be recirculated via a fluid circuit, for example, after reprocessing, and returned via the treatment fluid supply line 30.

[0035] However, the inventors 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 outer regions of the basin 10 than in the middle regions of the basin 10, as indicated by corresponding arrows P3 of different widths in Fig. 10 is indicated. However, this flow distribution has the consequence that the wafers 42 arranged in the wafer carrier 22 are not uniformly surrounded by the treatment fluid, so that the wafers are not treated uniformly.

[0036] Although the described example is designed to hold two wafer carriers, other examples may be designed for a different number of wafer carriers, such as an arrangement of four wafer carriers side by side, a 2x2 arrangement of four wafer carriers, an arrangement of 2x3 wafer carriers, or even just one wafer carrier. While the example shown has only one filling tube, other examples could have a filling tube for each wafer carrier, that is, for each receiving area of ​​a wafer carrier.

[0037] In the examples, the holes 24 of the perforated plate 16 are arranged in a uniform, two-dimensional pattern. In the examples, the holes can be the same size. In the examples, the holes can be different sizes.

[0038] It goes without saying that the components of the device are made of suitable materials that are resistant to the treatment fluids or media with which the wafers are to be treated. For example, the individual components may consist of suitable metal or plastic materials.

[0039] Referring to the Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5 to Fig. Section 6 will now explain examples of the present invention in more detail. Referring above to the Fig. 7, Fig. 8, Fig. 9 to Fig. The details described in section 10 apply equally to the examples of the present invention and are not repeated here.

[0040] As in Fig. As shown in Figure 1, the device comprises the basin 10 for receiving the treatment fluid 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, which fluidically connect the lower region 20 and the upper region 18. The filling tube 26 is arranged in the lower region 20 of the basin 10 and has, along its longitudinal direction (in Fig. (1 from left to right) the filling pipe openings 28, which in the example shown are oriented towards the underside of the basin, i.e., the bottom 14. Furthermore, separating elements 50 are provided in the lower area 20 of the basin, only some of which are marked with the reference numeral 50. The separating elements can be arranged as shown in Fig. 2 is shown, located on the bottom 14 of the basin, with in Fig. 2 For illustrative purposes, a slight gap is shown between separating element 50 and the pelvic floor 14. It should be noted here that the number of separating elements in the Fig. 1 and Fig. 3, although this is only for illustrative purposes. In the example shown, the separating elements extend in the transverse direction (perpendicular to the longitudinal direction of the filling tube 26) at least over the area of ​​the perforated plate 16 in which the holes 24 are provided. As in Fig. As indicated in section 3, the perforated plates can also extend laterally beyond this area, for example to the side walls of the basin, in Fig. 3 above and below.

[0041] In the examples, the separating elements are plate-shaped. In the examples, the separating elements extend, at least in a central area, from the bottom 14 of the basin 10 to the perforated plate 16, as best illustrated in Fig. Figure 2 shows that in outer edge areas, the separating elements 50 can be spaced away from the bottom of the basin, particularly if the bottom rises in the outer edge areas, as shown in Figure 2. Fig. 2 is shown.

[0042] 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°.

[0043] In some examples, a separating element 50 is provided between each adjacent pair of filling pipe openings. In other examples, a smaller number of separating elements could be provided, for example, with two filling pipe openings between each pair of separating elements. In other examples, the separating elements could be arranged irregularly, with the distance between separating elements being greater in a central area and less in an outer area.

[0044] The partition elements 50, which are arranged below the perforated plate 16, i.e., below the wafer support plane, divide the lower area 20 into compartments that segment the flow from the filling tube. In some examples, the compartments have the shape of lines running perpendicular to the longitudinal direction of the filling tube 26. Such segmentation of the flow cannot be achieved with a simple filling tube.

[0045] In some examples, the dividers can extend to the bottom of the basin, to the top of the perforated plate, and laterally at least to the end of the area where the holes in the perforated plate are located. This completely prevents longitudinal currents along the filling pipe past the dividers in this area. In other examples, the upper and lower ends of the dividers can be spaced away from the perforated plate and the bottom of the basin, respectively. In some examples, the dividers can be attached to the filling pipe. In others, the dividers can be attached to the perforated plate and have a recess below the filling pipe, allowing the dividers to be slid over the filling pipe from above. In still others, the dividers can be attached to the bottom and have a recess above the filling pipe, allowing the filling pipe to be inserted from above.Such a design of the separating elements with a recess can simplify assembly without significantly affecting functionality.

[0046] In some examples, the filling pipe openings 28 can be elongated in the longitudinal direction of the filling pipe. In others, the filling pipe openings 28 can have an extension in the longitudinal direction of the filling pipe that essentially corresponds to the distance between two separating elements 50, thereby enabling a more homogeneous distribution into the respective compartment.

[0047] The partitions reduce the flow of the treatment fluid in the longitudinal direction of the filling pipe 26 between the filling pipe openings 28, between which the partitions 50 are arranged. This results, as shown in Fig. As shown in Figure 1, a circular flow P4 is generated in the respective compartments. 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 Figure 1. Fig. 1 is indicated.

[0048] The separating elements, formed in the form of ribs, thus create a segmentation along the filling tube, which reduces differences in the flow rates through the holes 24 of the perforated plate 16 in the longitudinal direction of the filling tube 26. This allows the treatment fluid to flow more uniformly through the wafer carrier(s) 22 arranged in the upper region 18 of the basin 10. Consequently, a more uniform treatment of the wafers 42 arranged in the wafer carriers 22, through which the fluid flows from bottom to top, can be achieved.

[0049] 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.

[0050] Fig. Figure 4 shows a schematic cross-sectional view, which is essentially the same as in Fig. This corresponds to the representation shown in Figure 2, where fluid flows in the upper region 18 of the basin 10 are represented by arrows P6. The fluid flow tends to choose the path of least fluidic resistance and flows past the wafer supports 22, so that a large part of the fluid flows around the outside of the wafer supports, a part of the fluid flows between the two wafer supports shown, and only a small part of the fluid flow actually passes between the wafers 42 through the wafer supports 22.

[0051] To prevent this and to achieve a stronger and more homogeneous flow through the wafer carriers 22 and thus through the wafers 42 arranged in the wafer carriers 22, guide elements are provided in addition to the outer walls of the basin 10 in examples of the invention. These guide elements are arranged in the upper region 18 of the basin 10. Corresponding guide elements 60, 62 and 64 are shown in Fig. Figure 5 shows that the guide elements 60, 62, and 64 are arranged above the perforated plate 16 and can be attached to it. The guide element 60 defines a first receiving area for a wafer carrier at its outer edge, the guide element 64 defines a second receiving area for a wafer carrier at its outer edge, and the guide element 62 defines both receiving areas at their inner edges.

[0052] As in Fig. As shown in Figure 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 upwards 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 area of ​​the outer support rods 40. As shown in Fig. As can be seen in Figure 6, the side plates 44 of the wafer carrier 22 project 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 longitudinally and transversely along the filling tube. In other examples, the transverse distance between the respective guide elements could also correspond to the width of the end plates 44. In some examples, the side plates 44 do not project laterally beyond the rods 40, so that the distance between the respective guide elements corresponds to both the width in the area of ​​the rods and the width of the end plates.

[0053] In some examples, the sides of the guide elements facing the receiving areas are solid 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 held in the wafer carriers.

[0054] 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, meaning 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.

[0055] The lateral guide elements thus provide narrowly defined channels for the wafer carriers, through which the flow of the treatment medium through the perforated plate can be concentrated onto the wafer carriers. It should be noted that, as a rule, the wafers should not be positioned too close to the holes 24 of the perforated plate 16 to avoid overtreatment of the wafers at the points where they are closest to the holes. To achieve this, the end plates 44 can project downwards beyond the lower bars 40. Alternatively, supports can be provided in the basin 10 onto which the wafer carriers are placed.

[0056] In Fig. Figure 5 shows arrows P7, illustrating how the fluid flow is concentrated through the wafer carriers 22 by means of the guide elements 60, 62 and 64. Thus, examples of the present invention enable a concentrated and uniform treatment of the wafers 42, which are arranged in the wafer carriers 22, with a treatment medium that flows through the holes 24 in the perforated plate 16.

[0057] Although in the example shown, basin 10 has only two receiving areas for wafer carriers 22, in other examples, as explained above, the basin may 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 in the form of walls in the upper region 18 of basin 10. The guide elements do not have to be, as shown in Fig. As shown in Figure 5, the guide elements extend beyond the upper edge of the wafer carriers 22. In alternative examples, some or all of the guide elements may have a lower height. In yet other 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 each other or arranged very close together. In some examples, a guide element arranged between two wafer carriers may have a lower height than outer guide elements.

[0058] The guide elements thus enable targeted media flow through the wafer carriers and a homogeneous flow through them. This allows the treatment medium to be used more effectively, for example in etching processes or wafer cleaning. In addition to concentrating the medium through the wafer carriers, the guide elements also enable the positioning of the wafer carriers in the tank, eliminating the need for additional wafer carrier centering.

[0059] In appropriate wafer treatment processes, the pump 32, which is fluidically coupled to the treatment fluid supply line 30, is used (in Fig. (7 shown) Treatment fluid is pumped into the filling pipe 26 and through the filling pipe openings 28, thereby causing flows P5 of the treatment fluid through the holes 24 in the perforated plate 16 into the upper region 18 of the basin. These flows P5 can be homogenized due to the compartments formed by the separating elements 50, in contrast to the highly inhomogeneous flows that would occur without the separating elements; see the flows P3 in Fig. 10. These flows P5 allow wafers 42 in a wafer carrier 22, which was previously placed in the upper region 18 of the basin 10, to be treated uniformly with the treatment fluid. Furthermore, in some cases, the guide elements can be used to concentrate the flows through the wafer carriers and further homogenize the flow.

[0060] 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 or cleaning the wafer surfaces. Suitable treatment fluids for semiconductor wafers, for example silicon wafers, are known to those skilled in the art and require no further explanation here.

[0061] Although features of the invention have been described in terms of device features or process features, it is obvious to those skilled in the art that corresponding features can also be part of a process or a device. Thus, the device can be configured to perform corresponding process steps, and the respective functionality of the device can represent corresponding process steps.

[0062] In the preceding detailed description, various features were sometimes grouped together in examples to streamline the disclosure. This type of disclosure should not be interpreted as indicating that the claimed examples have more features than are expressly stated in each claim. Rather, as the following claims reflect, the subject matter may consist of fewer than all the features of a single disclosed example. Consequently, the following claims are hereby incorporated into the detailed description, with each claim potentially representing a separate, independent example.While each claim can stand as a separate example, it should be noted that, although dependent claims refer back 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 included unless it is stated that a specific combination is not intended. Furthermore, it is intended that a combination of features of a claim with any other independent claim is also included, even if that claim is not directly dependent on the independent claim.

Claims

[1] Device for treating wafers (42) with a treatment fluid, having the following features: a basin (10) for receiving the treatment fluid and the wafers (42) to be treated; a perforated plate (16) that separates the basin (10) into an upper area (18) and a lower area (20), wherein the perforated plate (16) has holes (24) that fluidically connect the lower area (20) and the upper area (18); a filling pipe (26) which is arranged in the lower area (20) of the basin (10) and has filling pipe openings (28) along its longitudinal direction, and 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 fluid in the longitudinal direction of the filling pipe (26) between the at least some of the filling pipe openings (28), where the filling pipe (26) is fluidically coupled in a longitudinally central area of ​​the same with a treatment fluid supply line (30) through which treatment fluid can be pumped into the filling pipe (26), and the filling pipe openings (28) are aligned towards the underside of the basin (10). [2] Device according to claim 1, wherein the separating elements (50) are designed to divide the lower area (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 tube openings (28), or wherein two or more filling tube openings (28) are provided between each pair of separating elements (50). [4] Device according to one of claims 1 to 3, wherein the separating elements (50) extend in the direction which intersects the longitudinal direction of the filling tube (26) over an area 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 tube (26). [6] Device according to one of claims 1 to 5, wherein the upper region (18) of the basin (10) has a receiving area for one or more wafer carriers (22) in which wafers (42) are arranged side by side with a distance between them. [7] Device according to claim 6, wherein the upper area (18) has several receiving areas to receive several wafer carriers (22) side by side in the longitudinal direction of the filling tube (26) and / or transversely to the longitudinal direction of the filling tube (26). [8] Device according to one of claims 6 or 7, wherein the holes (24) in the perforated plate (16) are distributed at least over the receiving area(s). [9] Device according to one of claims 6 to 8, which further comprises 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 limit the receiving area of ​​at least one wafer carrier (22) in order to concentrate a flow of the treatment fluid onto the receiving area. [10] Device according to claim 9, wherein the guide elements (60, 62, 64) limit 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). [11] Device according to claim 9 or 10, wherein the guide elements (60, 62, 64) are designed to position the at least one wafer carrier (22) in the basin (10). [12] Device according to claim 11, 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). [13] Device according to claim 11 or 12, 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). [14] Device according to one of claims 9 to 13, which has a plurality of corresponding guide elements (60, 62, 64) that laterally define receiving areas for a plurality of wafer carriers (22) in the upper area (18) of the basin (10). [15] Device according to claim 14, wherein the guide elements (60, 62, 64) have at least one guide element (62) that limits mutually facing sides of two adjacent receiving areas. [16] Device according to any one of claims 1 to 15, comprising a pump to pump the treatment fluid into the filling tube (26) and through the filling tube openings (28). [17] Method for treating wafers (42) with a treatment fluid using a device according to claim 16, comprising the following features: Inserting at least one wafer carrier (22) into the upper region (18) of the basin (10); Pumping the treatment fluid into the filling pipe (26) and through the filling pipe openings (28) by means of the pump, thereby causing flows of the treatment fluid through the holes (24) in the perforated plate (16) into the upper area (18) of the basin (10) in order to treat wafers (42) in the wafer carrier (22) with the treatment fluid, wherein the separating elements (50) reduce flows of the treatment fluid in the longitudinal direction of the filling pipe (26) between at least some of the filling pipe openings (28) and thereby reduce differences between flows of the treatment fluid through holes (24) of the perforated plate (16) arranged in the longitudinal direction of the filling pipe (26). [18] Method according to claim 17 using a device according to any one of claims 9 to 15, wherein the guide elements (60, 62, 64) are used as guides when inserting the at least one wafer carrier (22) into the upper region (18) of the basin (10).

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