METHOD AND DEVICE FOR TREATING SUBSTRATES

Abstract

In a method for treating substrates, the substrates are lowered for treatment into a treatment fluid contained in a treatment device. The substrates are then lifted by a first receiving device at least partially out of the treatment fluid and transferred to a second receiving device for completely lifting the substrates out of the treatment fluid. The second receiving device is completely dry at the time of transfer. The drops forming at the lowest point of the substrates are drained during lifting by a drop draining element. The device for performing the method has a lifting device with a first and second receiving device and a drop draining device for draining the drops forming at the lowest point of the substrates during lifting of the substrates from the treatment fluid.

Description

[0001] The invention concerns a method for the treatment of substrates, in which the substrates are treated in a treatment fluid and lifted in a reciprocating manner with a lifting device. Furthermore, the invention concerns a device for treating substrates in a treatment fluid with a lifting device.

[0002] A device for treating and a drying process, wherein disk-shaped substrates, for instance semiconductor wafers, are lifted with a lifting knife from a substrate carrier above the treatment fluid surface and inserted into guides of a hood, are known from DE 195 46 990 A1 of the applicant of this present patent application. After the treatment fluid has been drained from the treatment container, the dried substrates are lowered into the substrate carrier that has been dried as well and are then removed from the device together with the carrier.

[0003] This known device and method have been successfully used in practice. However, they are inefficient regarding the time required for this drying process. Furthermore, for the drying of the substrates the treatment fluid has to be drained, and this is not only time-consuming, but also requires a greater fluid consumption. Because the substrates have to be inserted into the guides of a hood during the lifting from the treatment fluid, a hood of the aforementioned kind is a necessary requirement. However, the insertion of substrates into the guides of the hood is only possible under great difficulties and with the danger of possible substrate breakage, in particular for rectangular and/or square substrates, or is not possible at all.

[0004] From EP 0 385 536 A1 a method and a device for drying substrates after treatment in a fluid are known in which the substrates are guided and secured in the guide slots of a fluid container. A lifting element presses the substrates that are held and guided in the guide slots of the fluid container in the upward direction and into an auxiliary cassette whereby the substrates, after complete removal form the treatment fluid, still remain in contact with the lifting element that is wetted with the treatment fluid. Drying of the substrates is thus not entirely ensured especially when the lifting element is at the same time the securing element for the substrates and thus has a relatively large contact area with the substrates.

[0005] Based on this, the object of the invention is the development of a method and device for the lifting of substrates into and out of a treatment fluid that eliminate the aforementioned drawbacks of conventional devices and, in particular, provides a fast and reliable drying process and lifting procedure with simple means and with a minimum of expenditure, especially for rectangular and/or square substrates.

[0006] The object of the invention for the aforementioned method is inventively solved by lifting the substrates with a first receiving device at least partially out of the treatment fluid and transfer them onto a second receiving device that is dry at the time of transfer of the substrates (3) to completely remove the substrates from the treatment fluid (8). With the inventive feature, guides outside of the container, for instance inside a hood, are no longer needed so that guides inside a hood or possibly the hood itself is not required so that handling of rectangular and/or square substrates without the danger of substrate breakage is possible.

[0007] Inasmuch as the second receiving device is not already dry, according to an especially advantageous embodiment of the invention, the second receiving device is being dried before it receives the substrates. The second receiving device can advantageously be dried in the same method step as the substrates. The already dried second receiving device advantageously contacts areas of substrates that have already been dried, i.e., that are already above the fluid surface above which the second receiving device is positioned during the transfer of the substrates.

[0008] According to another embodiment of the invention, the second receiving device then completely lifts the substrate areas that during the transfer from the first to the second receiving device were still in the treatment fluid, out of the fluid. No substrate area that has already been dried, contacts a receiving area that has yet to be dried. To achieve this, according to this invention, it is not necessary to drain the treatment fluid from the fluid container.

[0009] According to an especially advantageous embodiment of the invention, the first and second receiving devices are movable in a vertical direction relative to one another, wherein a reliable, safe transfer of the substrates from the first to the second receiving device is ensured. During the transfer procedure, the substrates continue to be lifted out of the treatment fluid with a generally constant speed without stops or sudden speed changes, thus minimizing the adherence of particles and contaminants at the substrates.

[0010] According to another very advantageous embodiment of the invention, the drops forming on the lowest point of the substrates are drained with a drop draining element. During the lifting of substrates, a last drop is forming on the lowest, bottom most part of the substrate that does not drain off or drains only with difficulty. By draining this drop with a drop draining element, this area also is dried fast and reliably.

[0011] According to another embodiment of the invention, the substrates are loaded into and/or onto the second support of the device for loading the device and are unloaded out of or from the second support for unloading the device. When using the inventive process, no additional guides and no additional substrate carriers are required.

[0012] The inventive method is, in particular, advantageous in conjunction with a drying process based on the Marangoni principle, wherein a gas or a gas mixture, for example, isopropyl alcohol, nitrogen or a mixture of these gases is applied to the substrates to be dried, thus accelerating the drying process substantially.

[0013] Based on the aforementioned device, the object of the invention is inventively further solved by providing a first receiving device to lift the substrates at least partially out of the treatment fluid and a second receiving device to take over the substrates partially lifted by the first receiving device, whereby the second receiving device is dry when receiving the substrates. The benefits of this improvement are identical to the benefits described above in conjunction with the inventive method. Here, it is also advantageous that the second receiving device is already dry during the transfer of the substrates from the first receiving device, i.e., analog to the drying process for the substrates, has already been dried, when the second receiving device is also lifted out of the treatment fluid. Areas of substrates already dried are only contacted by already dried areas of the second receiving device, so that the substrates do not contact the fluid again.

[0014] Very advantageous is a drop draining element that contacts the lowest part of the substrates at least when they have been completely lifted out of the treatment fluid. For rectangular or square substrates, the lowest point of a substrate is a corner of the substrate.

[0015] According to an advantageous embodiment of the invention, the first and second receiving devices are respectively connected to a driven and motion-controlled transport carriage in order to

[0016] included that are being treated in a treatment fluid and subsequently dried. The term substrates thus comprises not only semiconductor wafers, but also, in particular, LCD disks, compact disks, CDs, flat screens, masks, etc.

[0017] The invention as well as additional features and benefits thereof is/are described in the following with the aid of FIGS. 1 through 6 schematically showing the inventive device and the step sequence of the inventive process.

[0018] FIGS. 1 through 6 schematically show a first receiving device 1 with the receiving areas 1a and 1b as well as a second receiving device 2 with the receiving areas 2a and 2b. The embodiment shown describes the invention in conjunction with the treatment of square substrates 3 that are, as being described in this example, received in the first receiving device 1 as well as the second receiving device 2.

[0019] A knife-shaped drop draining element 4 is connected to the second receiving device 2 by arms 5, 6 such that the tip 7 of the knife-shaped draining element 4 is positioned at a constant distance to the second receiving device 2 and touches the lower corner of the square substrate 3 when the substrates 3 are positioned in or on the receiving device 2.

[0020] Reference number 8 schematically indicates the fluid surface of the treatment fluid 9, into which the substrates are lowered or from which the substrates are lifted.

[0021] According to FIG. 1, the device is loaded with the substrates 3 by placing them from the top and above the fluid surface 8 parallel to each other as packages onto or into the second receiving device 2. To maintain the substrates 3 in their parallel, vertical arrangement relative to one another, the receiving device 2 and/or its receiving areas 2a and 2b are comprised of parallel extending support slots that hold the edges of the substrates 3.

[0022] The lower corners of the substrates 3 touch the tip 7 of the drop draining element 4 that, however, initially has no function during the loading of the device, shown in FIG. 1.

[0023] After loading of the second receiving device 2 with the substrates 3 according to FIG. 1, the first and second receiving devices 1, 2 are lowered until the substrates 3 are completely submerged in the treatment fluid 9, as shown in FIG. 2. In this position, the substrates are treated with a treatment fluid, for instance, a rinsing agent, as previously described, for instance, in DE 44 13 077 A.

[0024] During or after the treatment of the substrates 3 with the fluid, the first receiving device 1 is raised relative to the second receiving device 2, so that the substrates 3 are positioned in or on the first receiving device 1 and are released from the second receiving device 2. FIG. 2 shows this state.

[0025] After the treatment of the substrates 3 in the treatment fluid 9, the first as well as the second receiving devices 1, 2 are raised steadily and parallel to each other to the relative position shown in FIG. 3, thus lifting the substrates 3 above the fluid surface 8 as shown in FIG. 3 to, for instance, advantageously dry them in the area above the fluid surface 8 utilizing the Marangoni principle, which is described in EP 0 385 536 A1. In this manner, the second receiving device 2 with the receiving areas 2a and 2b is lifted above the fluid surface 8 as well and is dried utilizing the same principle, wherein the second receiving device 2 does not contact the substrates 3. During this step, the substrates 3 are being held by the receiving device 1.

[0026] After the receiving device 2 and the edge areas of the substrates 3 that have already been lifted out of the treatment fluid 9 have been dried, the first receiving device I and the second receiving device 2 are moved in a relative manner to one another, so that the second receiving device 2 receives the substrates 3 that are consequently released by the first receiving device 1, as schematically shown in FIG. 4. Thus, in this lifting area, the second receiving device 2 passes in its upwardly movement the first receiving device.

[0027] As shown in FIG. 5, the remaining areas of the substrates 3 that were still submerged in the treatment fluid 9, are lifted above the fluid surface 8 and dried, without interference by the first receiving device 1 since it is not contacting the substrates 3 during this process step.

[0028] After the substrates 3 have been raised completely above the fluid surface 8, the draining element 4, whose tip 7 is contacting the lower corners of the substrates 3, causes the draining of the last drops on the lower corners of the substrates. FIG. 6 schematically shows this state as well as the position for unloading the substrates 3 that is the same as the ready position, corresponding to position 1a, for the next loading procedure.

[0029] The receiving devices 1, 2 are connected to non-represented drive devices that provide and control the travel course, the speed profile of the receiving devices 1, 2 and/or the relative movements of the receiving devices 1, 2 to one another. Advantageous embodiments of such

[0030] contacts the lower edge of the square substrate 3 when the substrates 3 are in or on the receiving device 2.

[0031] Reference number 8 schematically indicates the fluid surface of the treatment fluid 9, into which the substrates are lowered or from which the substrates are lifted.

[0032] According to FIG. 1, the device is loaded with the substrates 3 by placing them from the top and above the fluid surface 8 parallel to each other as packages onto or into the second receiving device 2. To maintain the substrates 3 in their parallel, vertical arrangement relative to one another, the receiving device 2 and/or its receiving areas 2a and 2b are comprised of parallel extending support slots that hold the edges of the substrates 3.

[0033] The lower corners of the substrates 3 touch the tip 7 of the drop draining element 4 that, however, initially has no function during the loading of the device, shown in FIG. 1.

[0034] After loading of the second receiving device 2 with the substrates 3 according to FIG. 1, the first and second receiving devices 1, 2 are lowered until the substrates 3 are completely submerged in the treatment fluid 9, as shown in FIG. 2. In this position, the substrates are treated with a treatment fluid, for instance, a rinsing agent, as previously described, for instance, in DE 44 13 077 A.

[0035] During or after the treatment of the substrates 3 with the fluid, the first receiving device 1 is raised relative to the second receiving device 2, so that the substrates 3 are positioned in or on the first receiving device 1 and are released from the second receiving device 2. FIG. 2 shows this state.

[0036] After the treatment of the substrates 3 in the treatment fluid 9, the first as well as the second receiving devices 1, 2 are raised steadily and parallel to each other to the relative position shown in FIG. 3, thus lifting the substrates 3 above the fluid surface 8 as shown in FIG. 3 to, for instance, advantageously dry them in the area above the fluid surface 8 utilizing the Marangoni principle, which is described in EP 0 385 536 A1. In this manner, the second receiving device 2 with the receiving areas 2a and 2b is lifted above the fluid surface 8 as well and is dried utilizing the same principle, wherein the second receiving device 2 does not contact the substrates 3. During this step, the substrates 3 are being held by the receiving device 1.

[0037] After the receiving device 2 and the edge areas of the substrates 3 that have already been lifted out of the treatment fluid 9 have been dried, the first receiving device 1 and the second receiving device 2 are moved in a relative manner to one another, so that the second receiving device 2 receives the substrates 3 that are consequently released by the first receiving device 1, as schematically shown in FIG. 4. Thus, in this lifting area, the second receiving device 2 passes in its upwardly movement the first receiving device.

[0038] As shown in FIG. 5, the remaining areas of the substrates 3 that were still submerged in the treatment fluid 9, are lifted above the fluid surface 8 and dried, without interference by the first receiving device 1 since it is not contacting the substrates 3 during this process step.

[0039] After the substrates 3 have been raised completely above the fluid surface 8, the draining element 4, whose tip 7 is contacting the lower corners of the substrates 3, causes the draining of the last drops on the lower corners of the substrates. FIG. 6 schematically shows this state as well as the position for unloading the substrates 3 that is the same as the ready position, corresponding to position 1a, for the next loading procedure.

[0040] The receiving devices 1, 2 are connected to non-represented drive devices that provide and control the travel course, the speed profile of the receiving devices 1, 2 and/or the relative movements of the receiving devices 1, 2 to one another. Advantageous embodiments for drive and lifting devices of this kind are described, in particular, in DE 195 46 990 A1 of the same applicant. This printed document is incorporated by reference into the present application to avoid repetition concerning this embodiment.

[0041] The invention has been disclosed with the aid of a preferred embodiment and reference to schematic figures. However, to a person skilled in the art various alterations, designs and modifications are obvious without departing from the gist of the invention. For example, the inventive method and the inventive device may also advantageously be implemented with substrates that are not square or rectangular, but have other shapes as well, for instance, disk-shaped substrates. It is also possible to embody the receiving devices 1, 2 differently according to the required use. Furthermore, the first receiving device 1 may remain below the fluid surface 8 and may not be lifted above it.

Claims

1. Method for the treatment of substrates (3), in which the substrates are treated in a treatment fluid (8) and lifted in a reciprocating manner with a lifting device, characterized in that the substrates (3) are lifted with a first receiving device (1) at least partially out of the treatment fluid (8) and are transferred to a second receiving device (2) and completely lifted out of the treatment fluid (8), wherein the second receiving device is completely dry at the time of transfer.

2. Method according to

claim 1, characterized in that the second receiving device (2) is dried, before it receives the substrates (3).

3. Method according to

claim 1 or

2, characterized in that the first and second receiving devices (1, 2) are moveable relative to one another in the vertical direction.

4. Method according to one of the preceding claims, characterized in that the drops on the lowest point (10) of the substrates (3) are being drained by a drop draining element (4).

5. Device according to one of the preceding claims, characterized in that the substrates (3) for loading the device are loaded into or onto the second receiving device (2).

6. Method according to one of the preceding claims, characterized in that the substrates (3) for unloading are unloaded out of or from the second receiving device (2).

7. Method according to one of the preceding claims, characterized in that during lifting out of the treatment fluid (8) the substrates (3) and/or the first and/or the second receiving device (1, 2) are treated with a gas.

8. Device according to

claim 7, characterized in that the gas is isopropyl alcohol, nitrogen, or a gas mixture of the two.

9. Device for the treatment of substrates (3) in a treatment fluid (8), comprising a lifting device, characterized by a first receiving device (1) for lifting the substrates (3) at least partially out of the treatment fluid (8) and a second receiving device (2) for receiving the substrates (3), wherein the second receiving device (2) during transfer of the substrates is dry.

10. Device according to

claim 9, characterized in that a drop draining element (4) is provided that contacts the lowest point (10) of the substrates (3).

11. Device according to one of the claims 9 or 10, characterized in that the substrates (3) are rectangular and the lowest point (10) of the substrates (3) is a corner (4) of the substrate (3).

12. Device according to one of the claims 9 through 11, characterized in that each one of the first and second receiving devices (1, 2) is connected to a transport carriage.

13. Device according to

claim 12, characterized in that the transport carriages and the first and second receiving devices (1, 2) are movable in a vertical direction relative to one another.

14. Device according to one of the claims 9 through 13, characterized in that the travel courses and/or the lifting speed of the transport carriages as well as their relative movement and/or relative speed to on another are controllable by at least one control curve.