JP2016187049A - Cleaning apparatus and cleaning method of wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning apparatus and a cleaning method of a wafer, which can achieve a uniform etching amount.SOLUTION: A wafer cleaning apparatus comprises: a tank where a wafer is arranged inside; a cleaning liquid injection device having a nozzle for jetting a cleaning liquid to the wafer arranged in the tank; a cleaning liquid supply device for supplying a cleaning liquid to cause the cleaning liquid to be accumulated in the tank; a discharge device for discharging the cleaning liquid in the tank from the bottom of tank; and a control device for controlling the cleaning liquid injection device, the cleaning liquid supply device and the discharge device so as to execute a first cleaning treatment to remove a chemical solution adhering to a surface of the wafer by jetting the cleaning liquid to the wafer arranged in the tank, and soaking the wafer in the cleaning liquid after the first cleaning treatment, and subsequently executing a second cleaning treatment to remove the chemical solution adhering to the surface of the wafer by discharging the cleaning liquid from the tank.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a wafer cleaning apparatus and a cleaning method in a semiconductor manufacturing process.

  In an etching process in a semiconductor manufacturing process, a wafer having a mask formed thereon is immersed in a chemical solution by irradiating a resist, and a pattern is formed on the wafer surface by etching only a portion where the mask is not formed. The wafer is taken out from the chemical solution when the etching has progressed to a desired depth. However, since a small amount of the chemical solution remains on the wafer taken out from the chemical solution, the progress of the etching cannot be completely stopped as it is. Therefore, it is necessary to remove the chemical from the wafer in order to stop the progress of etching. There are various methods for removing the chemical solution, and one of them is a quick damp rinse (QDR) method.

  In the quick dump rinse method, the wafer is immersed in a cleaning tank in which a cleaning liquid for removing a chemical solution is stored, and then the cleaning liquid is drained from the cleaning tank at once. By repeating the process a plurality of times, the chemical liquid adhering to the wafer is removed with the cleaning liquid. For such a quick dump rinse method, for example, an apparatus and a method as disclosed in Patent Document 1 have been proposed.

JP 2006-13015 A

  In recent years, high accuracy is required for wafer etching technology, and the above-described chemical removal needs to be performed accurately because it relates to the progress and accuracy of etching. However, in the conventional quick dump rinse method, the chemical removal amount in the wafer surface is uneven, and the etching amount may be uneven accordingly.

  Accordingly, an object of the present invention is to provide a wafer cleaning apparatus and a cleaning method capable of solving the above-described problems and realizing a uniform etching amount.

  In order to achieve the above object, a wafer cleaning apparatus of the present invention includes a tank in which a wafer is disposed, a cleaning liquid ejecting apparatus having a nozzle for injecting a cleaning liquid onto the wafer disposed in the tank, and a cleaning liquid in the tank. A cleaning liquid supply device for supplying a cleaning liquid so as to store the liquid, a discharge device for discharging the cleaning liquid in the tank from the bottom of the tank to the outside, and spraying the cleaning liquid onto the wafer disposed in the tank, thereby adhering to the wafer surface The second cleaning is performed to remove the chemical attached to the wafer surface by performing a first cleaning process for removing the chemical liquid, immersing the wafer in the cleaning liquid after the first cleaning process, and then discharging the cleaning liquid from the tank. A control device that controls the cleaning liquid ejecting apparatus, the cleaning liquid supply apparatus, and the discharge apparatus so as to execute the processing.

  Further, the wafer cleaning apparatus of the present invention includes a tank in which a wafer is disposed, a cleaning liquid spraying apparatus having a nozzle for spraying a cleaning liquid onto the wafer disposed in the tank, and the cleaning liquid in the tank from the bottom of the tank. A discharge device that discharges to the wafer, and a cleaning liquid injection device that executes a cleaning process that discharges the cleaning solution in the tank to the outside while removing the chemical liquid that has adhered to the wafer surface by spraying the cleaning liquid onto the wafer disposed in the tank And a control device for controlling the discharge device.

  Further, the wafer cleaning method of the present invention is a first cleaning process for removing a chemical solution adhering to the wafer surface by placing a wafer in the bath, and spraying the cleaning liquid onto the wafer placed in the bath. And a second cleaning step of removing the chemical solution adhering to the wafer surface by immersing the wafer in the cleaning solution after the first cleaning step and then discharging the cleaning solution from the tank.

  Further, the wafer cleaning method of the present invention includes a placement step of placing a wafer in the tank, and a cleaning liquid in the tank while removing the chemical liquid adhering to the wafer surface by spraying the cleaning liquid onto the wafer placed in the tank. It has a cleaning process for discharging to the outside and an unloading process for unloading the wafer to the outside of the tank.

  According to the cleaning apparatus and the cleaning method of the present invention, it is possible to provide a wafer with a uniform etching amount by spraying the cleaning liquid onto the wafer and removing the chemical liquid adhering to the wafer surface before immersing the wafer in the cleaning liquid. .

  Further, according to another cleaning apparatus and cleaning method of the present invention, the cleaning liquid in the tank is discharged to the outside while spraying the cleaning liquid onto the wafer disposed in the tank and removing the chemical liquid adhering to the wafer surface. A wafer with a uniform etching amount can be provided.

Sectional drawing which shows the washing | cleaning apparatus concerning Embodiment 1, 2 of this invention. Top view showing the cleaning apparatus of FIG. Top view showing a wafer used in the first and second embodiments Flowchart showing the procedure of the first embodiment 1 is a cross-sectional view showing the cleaning apparatus of FIG. 1 in which a wafer is arranged. Top view showing the cleaning apparatus of FIG. The flowchart which shows the procedure of Embodiment 2. Sectional drawing which shows the modification of a washing | cleaning-liquid injection apparatus Sectional drawing which shows the modification of a washing | cleaning-liquid injection apparatus Side view showing a modification of the cleaning liquid ejecting apparatus Sectional drawing which shows the modification of a washing | cleaning-liquid injection apparatus The figure which shows the result of the etching amount on the horizontal center axis | shaft of a wafer by a prior art example The figure which shows the result of the etching amount on the vertical center axis | shaft of a wafer by a prior art example The figure which shows the result of the etching amount on the horizontal center axis | shaft of a wafer by Example 1 The figure which shows the result of the etching amount on the vertical center axis | shaft of a wafer by Example 1 The figure which shows the result of the etching amount on the horizontal center axis | shaft of a wafer by Example 2 The figure which shows the result of the etching amount on the vertical center axis | shaft of a wafer by Example 2

  Embodiments according to the present invention will be described below in detail with reference to the drawings.

(Embodiment 1)
1 and 2 show a cleaning apparatus 1 according to a first embodiment of the present invention. FIG. 1 is a cross-sectional view of the cleaning device 1, and FIG. 2 is a top view of the cleaning device 1.

  As shown in FIG. 1, the cleaning apparatus 1 includes a tank 3 in which a wafer 2 is disposed, a sink 4 that is disposed so as to cover the tank 3, and that stores liquid overflowing from the tank 3, The cleaning liquid ejecting device 5 for spraying the cleaning liquid onto the wafer 2 arranged in the above, the cleaning liquid supply device 6 for supplying the cleaning liquid so as to store the cleaning liquid in the tank 3, and the cleaning liquid in the tank 3 are discharged to the outside. A discharge device 7 for cleaning, a cleaning liquid injection device 5, a cleaning liquid supply device 6, and a control device 8 for controlling the discharge device 7.

  As shown in FIGS. 1 and 2, the tank 3 has a substantially rectangular parallelepiped shape with an opening formed above, and the wafer 2 is disposed at the center of the tank 3.

  As shown in FIG. 1, the cleaning liquid injection device 5 includes a shower nozzle 9 that injects the cleaning liquid into the tank 3, and a shower pipe 10 that is connected to the shower nozzle 9 and supplies the cleaning liquid to the shower nozzle 9. As shown in FIG. 2, a pair of shower pipes 10 is provided on the left and right sides in a state of being connected to a plurality of shower nozzles 9. As shown in FIG. 1, the shower nozzles 9 connected to the left and right shower pipes 10 are provided so as to face each other at the left and right ends of the tank 3 and slightly above, and the direction of the shower nozzles 9 is the same as that of the wafer 2. It is directed slightly downward in the center so that the cleaning liquid can be sprayed to the central part. With such an arrangement of the shower nozzle 9, the cleaning liquid is sprayed from the left and right directions onto the wafer 2.

  Further, the cleaning liquid ejecting apparatus 5 is connected to the shower pipe 10 through a pipe and is also connected to a cleaning liquid supply source 22 existing outside the tank 3 so that the cleaning liquid can be supplied from the cleaning liquid supply source 22 to the shower pipe 10. And a shower valve 12 disposed in the middle of the pipe connecting the shower pipe 10 and the shower supply port 11. By opening and closing the shower valve 12, the supply and stop of the cleaning liquid via the pipe connecting the shower pipe 10 and the shower supply port 11 are adjusted. In the first embodiment, the shower valve 12 is a control valve that is automatically controlled by the control device 8.

  By controlling the shower valve 12 to the open state, the cleaning liquid from the cleaning liquid supply source 22 flows from the shower supply port 11 to the shower nozzle 9 through the shower pipe 10, and the cleaning liquid is jetted from the shower nozzle 9. On the other hand, when the shower valve 12 is controlled to be closed, the cleaning liquid does not flow from the shower supply port 11 to the shower pipe 10, and thus the cleaning liquid is not jetted from the shower nozzle 9. In the first embodiment, ultrapure water that can exhibit an excellent cleaning effect is used as the cleaning liquid. However, other liquids suitable for chemical cleaning of pure water and wafers (for example, IPA) Solvent) may be used.

  As shown in FIG. 1, the cleaning liquid supply device 6 is arranged in the tank 3 and supplies a cleaning liquid for storing the cleaning liquid in the tank 3, and the cleaning liquid supply nozzle 13 through a pipe. And a cleaning liquid supply port 14 that enables supply of the cleaning liquid from the cleaning liquid supply source 22 to the cleaning liquid supply nozzle 13 by connecting to the cleaning liquid supply source 22 disposed outside the tank 3. Further, the cleaning liquid supply device 6 includes a cleaning liquid supply valve 15 disposed in the middle of a pipe connecting the cleaning liquid supply nozzle 13 and the cleaning liquid supply port 14. By opening and closing the cleaning liquid supply valve 15, the cleaning liquid supply device 15 supplies the cleaning liquid. Adjust supply and stop. In the first embodiment, the cleaning liquid supply valve 15 is also a control valve that is automatically controlled by the control device 8, similarly to the shower valve 12.

  By controlling the cleaning liquid supply valve 15 to the open state, the cleaning liquid from the cleaning liquid supply source 22 flows from the cleaning liquid supply port 14 through the pipe to the cleaning liquid supply nozzle 13, and the cleaning liquid is supplied from the cleaning liquid supply nozzle 13 into the tank 3. The On the other hand, when the cleaning liquid supply valve 15 is controlled to be in the closed state, the cleaning liquid does not flow from the cleaning liquid supply port 14 to the pipe, so that the cleaning liquid is not supplied from the cleaning liquid supply nozzle 13. In the first embodiment, as the cleaning liquid of the cleaning liquid supply device 6, ultrapure water similar to the cleaning liquid ejecting apparatus 5 is used, but a liquid different from the cleaning liquid of the cleaning liquid ejecting apparatus 5 may be used. The supply port 14 may be connected to a supply source different from the cleaning liquid supply source 22.

  As shown in FIG. 1, the discharge device 7 includes a cleaning liquid discharge pipe 16 that discharges the cleaning liquid in the tank 3 to the outside, and a cleaning liquid discharge pipe valve 17 disposed in the middle of the cleaning liquid discharge pipe 16. The supply and stop of the cleaning liquid via the cleaning liquid discharge pipe 16 are adjusted by opening and closing the cleaning liquid discharge pipe valve 17. In the first embodiment, the cleaning liquid discharge pipe valve 17 is also a control valve that is automatically controlled by the control device 8, like the shower valve 12 and the cleaning liquid supply valve 15.

  By controlling the cleaning liquid discharge pipe valve 17 to the open state, the cleaning liquid in the tank 3 is discharged to the outside through the cleaning liquid discharge pipe 16 and quick dump rinsing described later is performed. The shape and size of the cleaning liquid discharge pipe 16 are designed so that the cleaning liquid in the tank 3 can be discharged in a short time during quick dump rinsing. On the other hand, when the cleaning liquid discharge pipe valve 17 is controlled to be closed, the cleaning liquid in the tank 3 is not discharged from the cleaning liquid discharge pipe 16. If the cleaning liquid is continuously supplied from the cleaning liquid injection device 5 or the cleaning liquid supply device 6 into the tank 3 while the cleaning liquid discharge pipe valve 17 is kept closed, the cleaning liquid in the tank 3 overflows. The overflow cleaning liquid flows to the sink 4 and is discharged to the outside through the sink drain 18 formed in the sink 4.

  FIG. 3 is a top view of the wafer 2 used in the first embodiment. The wafer 2 has already been etched by chemical treatment, and a desired pattern is formed on the surface of the wafer 2 although not shown in the drawing. As shown in FIG. 3, the wafer 2 has a substantially disk shape with a diameter of about 100 mm, and a linear portion (orientation flat or simply referred to as an orientation flat 19) is formed on the upper side in FIG. 3.

  Next, a method for cleaning the chemical solution remaining from the wafer 2 using the cleaning apparatus 1 having the above-described configuration will be described with reference to the flowchart shown in FIG. In addition, each process demonstrated below is implemented by controlling each structure part based on the program and driving | running condition which were preset by the control apparatus 8 with which the washing | cleaning apparatus 1 is provided.

(Arrangement process)
First, the arrangement process (step S1) in the flowchart of FIG. 4 is performed. Specifically, the wafer 2 is held in the carrier 20 and is placed in the tank 3 together with the carrier 20. At this time, the shower valve 12, the cleaning liquid supply valve 15, and the cleaning liquid discharge pipe valve 17 are all controlled to be closed.

  The cleaning device 1 after the placement process is shown in FIGS. FIG. 5 is a cross-sectional view of the cleaning device 1, and FIG. 6 is a top view of the cleaning device 1. As shown in FIG. 6, in the first embodiment, two carriers 20 containing, for example, 25 wafers 2 are arranged in the tank 3 so that the wafers 2 are substantially parallel to each other while facing the vertical direction. Are arranged at predetermined intervals. In the first embodiment, the cleaning liquid is not stored in the tank 3 at the stage of the arrangement process. Various means (not shown) for arranging the wafer 2 and the carrier 20 can be used.

(First cleaning process)
Next, a 1st washing process (Step S2) is carried out. Specifically, as shown in FIG. 5, the cleaning liquid is sprayed from the shower nozzle 9 to the plurality of wafers 2 arranged in the tank 3. This is because ultra pure water is supplied to the shower nozzle 9 through the shower pipe 10 from the shower water supply port 11 connected to the cleaning liquid supply source 22 by controlling the shower valve 12 which has been closed to the open state. Do.

  When the ultrapure water sprayed from the shower nozzle 9 hits the surface of the wafer 2, the chemical solution remaining on the surface of the wafer 2 is removed by the cleaning action of the ultrapure water. At this time, since the wafers 2 are arranged in parallel with each other at a predetermined interval, a space for injecting ultrapure water is secured. Further, as shown in FIG. 6, since ultra pure water is sprayed from a plurality of shower nozzles 9 to one wafer 2, ultra pure water is sprayed from various angles to the surface of the wafer 2. be able to. Therefore, the injection of ultrapure water can be performed under uniform conditions on the center and the end of the surface of the wafer 2. Since the wafer 2 is arranged in the vertical direction, the used cleaning liquid including the removed chemical liquid falls from the wafer 2 and is stored in the tank 3.

(Second cleaning process)
Next, the second cleaning process (step S3) is performed. Specifically, first, ultrapure water is stored in the tank 3 by supplying ultrapure water from the cleaning liquid supply nozzle 13. This is performed by controlling the cleaning liquid supply valve 15 that has been closed to an open state, thereby supplying ultrapure water from the cleaning liquid supply port 14 connected to the cleaning liquid supply source 22 to the cleaning liquid supply nozzle 13 through a pipe. . When a predetermined time elapses after the supply of the ultrapure water from the cleaning liquid supply nozzle 13 is started, the wafer 2 is immersed in the ultrapure water, and when the time elapses, the tank 3 overflows with the ultrapure water. Due to the overflow, the ultrapure water containing the chemical solution adhering to the wafer 2 is discharged to the outside of the tank 3, whereby the surface of the wafer 2 is cleaned. The supply of ultrapure water is stopped by controlling the cleaning liquid supply valve 15 to be closed after a predetermined time has elapsed since the tank 3 overflowed. The injection of ultra pure water from the shower nozzle 9 to the wafer 2 performed in step S2 is continued after the start of step S3, and is stopped when the wafer 2 is immersed in ultra pure water.

  When the supply of the ultrapure water from the cleaning liquid supply nozzle 13 is stopped, the ultrapure water in the tank 3 is then discharged. That is, by controlling the cleaning liquid discharge pipe valve 17 that has been closed to an open state, the ultrapure water in the tank 3 is discharged to the outside of the tank 3 through the cleaning liquid discharge pipe 16 (quick dump rinse). When the liquid level in the tank 3 is lowered by the quick dump rinse, the chemical solution remaining on the surface of the wafer 2 is removed and the cleaning proceeds. When the discharge of the ultrapure water is completed, the cleaning liquid discharge pipe valve 17 is controlled to return to the closed state again.

  In the first embodiment, the chemical liquid on the surface of the wafer 2 is removed by repeating the supply of ultrapure water by the cleaning liquid supply nozzle 13 and the discharge of ultrapure water by the cleaning liquid discharge pipe 16 a plurality of times. In the same manner that the shower of ultrapure water by the shower nozzle 9 is continued until the wafer 2 is immersed after the end of step S2, the period from when the ultrapure water is discharged until the wafer 2 is immersed again. In order to prevent the wafer 2 from drying, ultra pure water is sprayed from the shower nozzle 9 to the wafer 2. As described above, by performing the second cleaning step after the first cleaning step, the surface of the wafer 2 that has already been cleaned in the first cleaning step can be further cleaned. The number of times of supplying and discharging ultrapure water is not limited to a plurality of times, and may be one.

(Unloading process)
Next, an unloading process (step S4) is implemented. Specifically, the wafer 2 is unloaded from the tank 3 together with the carrier 20 using unloading means (not shown). Various things can be used as a carrying-out means. The unloaded wafer 2 is sent to the subsequent semiconductor manufacturing process.

  As described above, the chemical solution adhering to the surface of the wafer 2 is removed by performing steps S1 to S4. According to the first embodiment, after the wafer 2 is placed in the tank 3, first, ultrapure water is sprayed onto the wafer 2 using the cleaning liquid spraying device 5 to remove the chemical (first cleaning process). By performing the above, it is possible to remove the chemical solution so that the etching amount becomes uniform regardless of the position on the wafer 2. The shower nozzle 9 is arranged so that the ultrapure water sprayed from a certain shower nozzle 9 overlaps with the ultrapure water sprayed from other adjacent shower nozzles 9. Since ultrapure water can be sprayed to various positions on the wafer 2, uniform ultrapure water spray and chemical removal can be performed regardless of the position on the wafer 2. Further, after the first cleaning step, the chemical solution remaining on the wafer 2 after the first cleaning step is removed by removing the chemical solution by the quick dump rinse (second cleaning step) using the cleaning liquid supply device 6. can do.

(Embodiment 2)
In the second embodiment of the present invention, the process of the flowchart shown in FIG. 7 is performed using the same cleaning apparatus 1 as in the first embodiment. Only differences from the first embodiment will be described below.

  The process of the second embodiment shown in FIG. 7 differs from the first embodiment in the cleaning process in step S2. The arrangement process in step S1 and the unloading process in step S3 are the same as those in the first embodiment. is there. Therefore, step S2 in particular from step S1 to step S3 will be described.

  The start state of step S2 in the second embodiment is the same as in FIGS. 5 and 6, and the wafer 2 held by the carrier 20 is arranged in the tank 3. From this point, in the first embodiment, the first cleaning process is performed by injecting ultrapure water from the shower nozzle 9 onto the wafer 2 while the cleaning liquid discharge pipe valve 17 is closed. In the second embodiment, after the cleaning liquid discharge pipe valve 17 is controlled to be in an open state, ultrapure water is sprayed from the shower nozzle 9 to the wafer 2. That is, the ultrapure water sprayed from the shower nozzle 9 to the wafer 2 is continuously discharged from the cleaning liquid discharge pipe 16 to the outside of the tank 3.

  After a predetermined time has elapsed from the start of the injection of ultrapure water from the shower nozzle 9, the shower valve 12 is controlled to be closed to stop the injection of ultrapure water from the shower nozzle 9, and the cleaning liquid is discharged. The pipe valve 17 is also controlled to be closed, and the discharge of the ultrapure water from the cleaning liquid discharge pipe 16 is also stopped. In the first embodiment, the quick dump rinse is further performed in the second cleaning step. However, in the second embodiment, the quick dump rinse is not performed, and only the injection of ultrapure water from the shower nozzle 9 is performed. Finish the cleaning process. By carrying out such a cleaning process, it is possible to remove the chemical solution so that the etching amount becomes uniform regardless of the position on the wafer 2, and even without using a large amount of ultrapure water such as quick dump rinse. 2 The chemical solution on the surface can be removed, leading to cost reduction.

  In the second embodiment, since it is not necessary to immerse the wafer 2 with ultrapure water, the cleaning liquid supply device 6 among the components of the cleaning device 1 can be omitted. Similarly, since it is not necessary to overflow the tank 3 with ultrapure water, the sink 4 and the sink drain 18 can be omitted. Thus, when the components of the cleaning device 1 are omitted, the configuration of the cleaning device 1 is simplified. Further, since the quick dump rinse is not performed in the second embodiment, the shape and size of the cleaning liquid discharge pipe 16 are not limited as in the first embodiment.

  In addition, this invention is not limited to the said embodiment, It can implement with another various aspect. For example, the modification is shown in FIGS. 8, 9, and 11 are cross-sectional views as seen from the front direction of the cleaning apparatus 1, that is, from the arrangement direction of the wafers 2, and FIG. 10 is a side view as seen from the direction orthogonal to the arrangement direction of the wafers 2. As shown in FIG. 8, the shower nozzles 9 are arranged so that adjacent ones are oriented in different directions, or two shower pipes 10 are installed on the left and right as shown in FIG. Thus, the shower nozzles 9 can be arranged in two stages. Furthermore, as shown in FIG. 10, the shower pipe 10 is provided with a rotation drive unit 21, and the rotation drive unit 21 is driven so that the shower nozzle 9 can be rotated (oscillated) along the arrangement direction of the wafers 2. You can also. Alternatively, as shown in FIG. 11, the shower nozzles 9 are arranged in a direction orthogonal to the arrangement direction of the wafers 2, and the rotation drive unit 21 similar to that in FIG. It is also possible to rotate (oscillate) along a direction orthogonal to. By performing such an arrangement, it is possible to spray the ultrapure water to various positions on the wafer 2 by appropriately changing the spray angle of the shower nozzle 9, thereby enabling uniform spraying. Note that three or more shower pipes 10 shown in FIG.

  In the first embodiment, it has been described that the injection of ultrapure water from the shower nozzle 9 to the wafer 2 is also performed at step S3 following step S2, but the injection of ultrapure water is stopped at the end of step S2. In step S3, the injection of ultrapure water by the shower nozzle 9 may not be performed.

  Next, the amount of etching (Examples 1 and 2) when the wafer 2 is cleaned according to the flowcharts of Embodiments 1 and 2 using the cleaning apparatus 1 and the cleaning of the wafer 2 by the conventional quick dump rinse method. The results of the etching amount (conventional example) when performing the above are compared below. As shown in FIG. 3, a straight line parallel to the orientation flat 19 passing through the center C of the circle is taken as the X axis, and a straight line perpendicular to the orientation flat 19 passing through the center C of the circle is taken as the Y axis. A direction and a distance from the center C of the circle are set. The unit of the numbers in the figure is mm.

(Conventional example)
In the conventional example, the wafer 2 is cleaned only by the quick dump rinsing process without spraying ultrapure water. That is, the wafer 2 is cleaned according to a flow obtained by removing the first cleaning step from the flowchart of the first embodiment shown in FIG. 12A and 12B show the results of the etching amount of the wafer 2 according to the conventional example. FIG. 12A is a graph showing the etching amount on the X axis (horizontal central axis) of the wafer 2, where the vertical axis is the etching amount (nm) of the wafer 2 and the horizontal axis is the X coordinate position (mm). FIG. 12B is a graph showing the etching amount on the Y axis (vertical central axis) of the wafer 2, where the vertical axis is the etching amount (nm) of the wafer 2 and the horizontal axis is the Y coordinate position (mm). As setting conditions, the injection amount of ultrapure water from the shower nozzle 9 is 8 L (liter) / min, the supply amount of ultrapure water from the cleaning liquid supply nozzle 13 is 10 L / min, and the number of quick dump rinse processes in the cleaning process However, the supply / discharge amount of ultrapure water per quick dump rinse process is about 20L.

Example 1
In Example 1, the wafer 2 is cleaned by the flow (FIG. 4) according to the first embodiment described above. 13A and 13B show the results of the etching amount of the wafer 2 according to Example 1. FIG. As setting conditions, the injection amount of ultrapure water from the shower nozzle 9 is 8 L / min, the supply amount of ultrapure water from the cleaning liquid supply nozzle 13 is 10 L / min, and the injection time of ultrapure water in the first cleaning step. The number of quick dump rinse processes in the second cleaning process is 30 times for 30 seconds, and the supply / discharge amount of ultrapure water per quick dump rinse process is about 20 L.

(Example 2)
In Example 2, the wafer 2 is cleaned by the flow (FIG. 7) according to the second embodiment described above. 14A and 14B show the results of the etching amount of the wafer 2 according to the second embodiment. As setting conditions, the injection amount of ultrapure water from the shower nozzle 9 is 10 L / min, and the injection time of ultrapure water in the cleaning process is 180 seconds.

  As shown in FIGS. 12A and 12B, according to the conventional example, the etching amount in the vicinity of the end portion of the wafer 2 varies in both the vertical direction and the horizontal direction. Further, as shown in FIG. 12B, the etching amount becomes smaller toward the upper side of the wafer 2 in the vertical direction.

  On the other hand, as shown in FIGS. 13A and 13B and FIGS. 14A and 14B, according to the first and second embodiments, there is almost no variation in the etching amount in the vicinity of the edge of the wafer 2. Further, as shown in FIG. 13B and FIG. 14B, the etching amount tends to decrease as it goes above the wafer 2 in the vertical direction, but the tendency is small as compared with the conventional example. Thus, compared with the conventional example, the first and second embodiments can uniformly remove the chemical solution adhering to the wafer 2, and as a result, the etching amount in the wafer 2 can be made uniform.

  In addition, this invention is not limited to the above-mentioned structure, It can implement in another various aspect. For example, before performing the cleaning process, the wafer 2 may be immersed in a cleaning tank in which hydrofluoric acid is stored for cleaning. As described above, by previously immersing the wafer 2 in hydrofluoric acid before cleaning with the cleaning liquid, it is possible to promote the cleaning effect by the cleaning liquid performed thereafter. Therefore, the chemical solution adhering to the wafer 2 can be removed more uniformly, and the etching amount can be made more uniform.

  It is to be noted that, by appropriately combining any of the above-described various embodiments, the effects possessed by them can be produced.

  Since the cleaning apparatus and the cleaning method according to the present invention can provide a wafer having a uniform etching amount, the cleaning apparatus and the cleaning method are useful for manufacturing a semiconductor element or the like that requires a high level of accuracy.

DESCRIPTION OF SYMBOLS 1 Cleaning apparatus 2 Wafer 3 Tank 4 Sink 5 Cleaning liquid injection apparatus 6 Cleaning liquid supply apparatus 7 Discharge apparatus 8 Control apparatus 9 Shower nozzle 10 Shower pipe 11 Shower supply port 12 Shower valve 13 Cleaning liquid supply nozzle 14 Cleaning liquid supply port 15 Cleaning liquid supply valve 16 Cleaning liquid Discharge pipe 17 Cleaning liquid discharge pipe valve 18 Sink drain 19 Orientation flat 20 Carrier 21 Rotation drive unit 22 Cleaning liquid supply source

Claims (17)

A tank in which a wafer is placed;
A cleaning liquid ejecting apparatus having a nozzle for ejecting a cleaning liquid onto a wafer disposed in the tank;
A cleaning liquid supply device that supplies the cleaning liquid so as to store the cleaning liquid in the tank;
A discharge device for discharging the cleaning liquid in the tank to the outside from the bottom of the tank;
A first cleaning process is performed to remove the chemical solution adhering to the wafer surface by spraying the cleaning liquid onto the wafer disposed in the tank. After the first cleaning process, the wafer is immersed in the cleaning liquid, and then from the tank. A wafer cleaning apparatus comprising: a cleaning liquid ejecting apparatus, a cleaning liquid supply apparatus, and a control apparatus for controlling the discharging apparatus so as to execute a second cleaning process for removing the chemical liquid attached to the wafer surface by discharging the cleaning liquid. .   The wafer cleaning apparatus according to claim 1, wherein the second cleaning process is repeated a plurality of times. A tank in which a wafer is placed;
A cleaning liquid ejecting apparatus having a nozzle for ejecting a cleaning liquid onto a wafer disposed in the tank;
A discharge device for discharging the cleaning liquid in the tank to the outside from the bottom of the tank;
Control for controlling the cleaning liquid ejecting device and the discharging device so as to execute a cleaning process for discharging the cleaning liquid in the bath to the outside while removing the chemical liquid adhering to the wafer surface by spraying the cleaning liquid onto the wafer disposed in the bath And a wafer cleaning apparatus.   The cleaning apparatus according to claim 1, wherein adjacent nozzles in the cleaning liquid ejecting apparatus are arranged at different angles so as to eject to different portions of the wafer.   The cleaning apparatus according to claim 1, wherein the cleaning liquid spraying apparatus is swingable so as to spray to different portions of the wafer.   The cleaning apparatus according to claim 1, further comprising a cleaning tank that immerses and cleans the wafer in hydrofluoric acid before performing the first cleaning process.   The cleaning apparatus according to any one of claims 1 to 6, wherein the cleaning liquid is ultrapure water. An arrangement step of arranging the wafer in the tank;
A first cleaning step of removing a chemical liquid adhering to the wafer surface by spraying the cleaning liquid onto the wafer disposed in the tank;
A wafer cleaning method comprising: a second cleaning step of removing the chemical solution adhering to the wafer surface by immersing the wafer in a cleaning solution after the first cleaning step and then discharging the cleaning solution from the tank.   The cleaning method according to claim 8, wherein the second cleaning step is repeated a plurality of times.   The cleaning method according to claim 8 or 9, wherein in the first cleaning step, a plurality of adjacent nozzles arranged at different angles eject the cleaning liquid onto different portions of the wafer to remove the chemical liquid.   11. The method according to claim 8, wherein in the first cleaning process, the nozzle sprays the cleaning liquid onto different portions of the wafer and the chemical liquid is removed by swinging a device that sprays the cleaning liquid onto the wafer. Cleaning method.   The cleaning method according to claim 8, wherein the wafer is immersed in hydrofluoric acid for cleaning before the first cleaning step. An arrangement step of arranging the wafer in the tank;
A cleaning step of discharging the cleaning liquid in the tank to the outside while removing the chemical liquid adhering to the wafer surface by spraying the cleaning liquid on the wafer disposed in the tank;
A wafer unloading process for unloading the wafer to the outside of the bath.   The cleaning method according to claim 13, wherein in the cleaning step, a plurality of adjacent nozzles arranged at different angles eject the cleaning liquid onto different portions of the wafer to remove the chemical liquid.   The cleaning method according to claim 13 or 14, wherein, in the cleaning step, the nozzle sprays the cleaning liquid onto different portions of the wafer to remove the chemical liquid by swinging a device for spraying the cleaning liquid onto the wafer.   The cleaning method according to claim 13, wherein the wafer is cleaned by immersing it in hydrofluoric acid before the cleaning step.   The cleaning method according to any one of claims 8 to 16, wherein the cleaning liquid is ultrapure water.

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