JP7413087B2 - Wet etching method - Google Patents

Description

The present invention relates to a wet etching method.

Patent Documents 1 to 3 disclose a wet etching method in which an etching solution is stored on the upper surface of a silicon wafer and the upper surface of the wafer is wet-etched.
After wet etching using such a wet etching method, in order to clean the wafer, the wafer is held on a table, and while a cleaning solution is supplied from above the center of the wafer held on the table, the wafer is rotated around the center of the wafer. The etching solution adhering to the upper surface of the wafer is removed by rotating the wafer and causing the cleaning solution to flow from the center to the outer periphery of the wafer.

By storing the etching solution on the upper surface of the wafer and performing etching, it is possible to save the etching solution and to make the etching speed uniform for each wafer. In this way, when the cleaning liquid is supplied to the top surface of the rotating wafer, the cleaning liquid supplied to the top surface of the wafer is scattered.

Japanese Patent Application Publication No. 1990-086130 Japanese Patent Application Publication No. 1994-265869 JP2017-028257A

Etching using the above etching method has a slow etching rate. Therefore, the wet etching method has the problem of increasing the etching rate.
Furthermore, the wet etching method also has the problem of suppressing the scattering of the cleaning liquid.

The present invention is a wet etching method for etching the upper surface of a wafer using an etching solution, which includes an etching solution supply step in which the etching solution is accumulated on the upper surface of the wafer due to surface tension, and a step in which the etching solution accumulated on the upper surface of the wafer is Sucking up the etching solution accumulated on the upper surface of the wafer due to surface tension using an etching solution suction pump whose tip communicates with the nozzle that has applied the liquid and is capable of sucking the etching solution accumulated on the upper surface of the wafer; An etching process in which the sucked etching solution is returned to the top surface of the wafer from the etching solution suction pump , and the process is repeated to generate a flow of the etching solution on the top surface of the wafer to etch the top surface of the wafer. After the etching process, the wafer is This wet etching method includes a cleaning step of cleaning the upper surface of the wafer.
The cleaning process for the above wet etching method includes a cleaning liquid supply process in which the cleaning liquid is stored on the top surface of the wafer due to surface tension, and a nozzle whose tip is immersed in the cleaning liquid stored on the top surface of the wafer. Using a cleaning liquid suction pump capable of suctioning the cleaning liquid accumulated on the upper surface, the cleaning liquid accumulated on the upper surface of the wafer is sucked up by surface tension, and the sucked cleaning liquid is returned to the upper surface of the wafer from the cleaning liquid suction pump. It is desirable that this process be repeated to generate a flow of the cleaning liquid on the upper surface of the wafer .
After the cleaning step in preparation for the above wet etching method, a mask removing step is included to remove the mask formed on the upper surface of the wafer, and the mask removing step includes supplying a mask removing liquid to accumulate the mask removing liquid on the upper surface of the wafer due to surface tension. During the process, a mask removal liquid suction pump that communicates with a nozzle whose tip is immersed in the mask removal liquid stored on the top surface of the wafer and is capable of suctioning the mask removal liquid stored on the top surface of the wafer is used to remove the mask removal liquid from the surface. The mask is removed from the top surface of the wafer by repeatedly sucking up the mask removal liquid accumulated on the top surface of the wafer due to tension and returning the sucked mask removal liquid from the mask removal liquid suction pump to the top surface of the wafer. It is desirable that the process produces a flow of liquid .

When etching a wafer, the etching speed can be increased by using an etching liquid suction pump to suck up the etching liquid accumulated on the top surface of the wafer, and by resupplying the sucked etching liquid to the top surface of the wafer. . Further, scattering of the etching solution can be suppressed. Furthermore, the use of etching solution can be reduced.
When cleaning the wafer, the cleaning liquid suction pump is used to repeatedly suck and supply the cleaning liquid, thereby increasing the cleaning speed and shortening the time required to clean the wafer. Further, it is possible to suppress the cleaning liquid from scattering. Furthermore, cleaning fluid can be saved.
When removing the mask from the wafer, the mask removal liquid suction pump is used to repeatedly suck and supply the mask removal liquid, thereby increasing the mask removal speed and shortening the time required to remove the mask from the wafer. Further, scattering of the mask removal liquid can be suppressed. Furthermore, the second liquid can be omitted.

FIG. 3 is a cross-sectional view showing the state of the preparation process. FIG. 3 is a perspective view of a wafer support. FIG. 3 is a perspective view showing the wafer support attached to the etching liquid bottle. It is a sectional view showing an etching liquid supply process. FIG. 3 is a cross-sectional view showing an etching process. It is a sectional view showing a cleaning process. FIG. 3 is a cross-sectional view showing a state in which the first liquid is supplied to the upper surface of the wafer and the supplied first liquid is sucked from the upper surface of the wafer. FIG. 7 is a cross-sectional view illustrating how the supply of the second liquid to the upper surface of the wafer and the suction from the upper surface of the wafer are repeated. FIG. 2 is a cross-sectional view showing how a wafer is dried. FIG. 2 is a perspective view showing how the wafer support is fixed to the drying device.

1 Preparation Step The wet etching method for the wafer 11 will be described below. First, as shown in FIG. 1, the wafer 11 is placed on the wafer support 3.

Here, the wafer support 3 will be explained. The wafer support 3 shown in FIG. 2 is a support on which the wafer 11 is supported.
The wafer support 3 includes a main body 30 that supports the wafer 11. The main body section 30 includes a base section 34 on which the wafer 11 is placed. The base portion 34 includes an annular inner frame portion 340 and an annular outer frame portion 342 disposed outside the inner frame portion 340. The outer frame portion 342 is formed to have a larger diameter than the inner frame portion 340, and the center of the ring of the inner frame portion 340 and the center of the ring of the outer frame portion 342 are coincident.
The inner frame part 340 and the outer frame part 342 are connected by a plurality of connecting parts 341 arranged between the inner frame part 340 and the outer frame part 342. A region surrounded by the inner frame portion 340, the outer frame portion 342, and the connecting portion 341 is a hole portion 343.

A plurality of columns 35 are erected on the upper surface of the outer frame portion 342 of the base portion 34 at equal intervals. In this embodiment, six columns 35 are erected on the upper surface of the outer frame portion 342. A ring portion 33, which is an annular member formed to have the same diameter as the outer frame portion 342, is supported on the support column 35.

A plurality of legs 31 extending radially toward the outside of the ring portion 33 are connected to the side surface of the ring portion 33 . A fastener 32 is connected to the end of the leg 31 on the side that is not connected to the ring part 33.

2 Etching liquid supply process After placing the wafer 11 on the base part 34 of the wafer support 3 in the preparation process, as shown in FIG. Attach to.

Here, the etching solution bottle 91 is provided with an opening 911 having an outer diameter slightly smaller than the outer diameter of a circle drawn by the plurality of fasteners 32 of the wafer support 3 .
By placing the main body 30 of the wafer support 3 approximately in the center of the opening 911 of the etching liquid bottle 91, the legs 31 come into contact with the upper surface 910 of the etching liquid bottle 91, and the legs 31 and the fasteners 312 It engages with the outer periphery of the etching liquid bottle 91. Thereby, the wafer support 3 is attached to the etching liquid bottle 91.

After the wafer support 3 is attached to the etching liquid bottle 91, the etching liquid 400 is supplied to the upper surface 110 of the wafer 11.
When supplying the etching liquid 400 to the upper surface 110 of the wafer 11, first, as shown in FIG. 4, the etching liquid nozzle 40 is connected to the etching liquid supply source 41. Then, the etching liquid nozzle 40 connected to the etching liquid supply source 41 is positioned above the wafer 11.

Here, an etching liquid 400 is stored in the etching liquid supply source 41 .
Etching liquid 400 is supplied from etching liquid supply source 41 while etching liquid nozzle 40 is positioned above wafer 11 . As a result, the etching liquid 400 is supplied to the upper surface 110 of the wafer 11, and the etching liquid 400 is accumulated on the upper surface 110 of the wafer 11 due to the surface tension acting on the upper surface 110 of the wafer 11.
When a predetermined amount of the etching liquid 400 is stored on the upper surface 110 of the wafer 11, the tip 43 of the etching liquid nozzle 40 is brought into contact with the etching liquid 400.

At this time, of the etching liquid 400 supplied to the upper surface 110 of the wafer 11, the one that overflows from the upper surface 110 of the wafer 11 is collected inside the etching liquid bottle 91.

3 Etching Step After the etching liquid 400 is supplied to the upper surface 110 of the wafer 11, the etching liquid 400 is sucked from the upper surface 110 of the wafer 11 using the etching liquid suction pump 42 shown in FIG.

Specifically, first, an etching liquid suction pump 42 shown in FIG. 5 is connected to the etching liquid nozzle 40 instead of the etching liquid supply source 41 shown in FIG. 4 .

Then, with the etching liquid suction pump 42 connected to the etching liquid nozzle 40, the etching liquid suction pump 42 is used to suck up the etching liquid 400 stored on the upper surface 110 of the wafer 11.

Here, the etching liquid suction pump 42 is, for example, an air cylinder mechanism including a cylinder 421 and a piston 422 disposed inside the cylinder 421, and the piston 422 is connected to a suction source (not shown). Further, a space formed by the lower surface and side surface of the cylinder 421 and the lower surface of the piston 422 serves as a storage chamber 410 that can contain the etching liquid 400.

When sucking up the etching liquid 400 stored on the top surface 110 of the wafer 11, the top surface of the piston 422 is sucked using the suction source. Then, the upper surface of the piston 422 is pulled up in the +Z direction, the pressure inside the storage chamber 410 becomes negative pressure, and suction force is generated in the storage chamber 410, and the generated suction force is applied to the etching liquid nozzle 40. communicated. As a result, the etching liquid 400 deposited on the upper surface 110 of the wafer 11 is sucked in from the etching liquid nozzle 40 and accommodated in the storage chamber 410.

Next, using the etching liquid suction pump 42, the etching liquid 400 sucked into the storage chamber 410 of the etching liquid suction pump 42 is returned to the upper surface 110 of the wafer 11.
Specifically, the suction source is stopped and the suction force acting on the piston 422 is removed. Then, for example, the piston 422 descends in the -Z direction due to its own weight, and the etching solution 400 accommodated in the accommodation chamber 410 receives a pressing load from the piston 422 and is pushed out from the accommodation chamber 410 and passes through the etching solution nozzle 40. and returned to the upper surface 110 of the wafer 11.

As described above, using the etching liquid suction pump 42, sucking up the etching liquid 400 accumulated on the upper surface 110 of the wafer 11 and returning the sucked etching liquid 400 to the upper surface 110 of the wafer 11 are repeated. As a result, the etching liquid 400 flows on the upper surface 110 of the wafer 11, and the upper surface 110 is etched.

Note that when repeatedly sucking up the etching liquid 400 accumulated on the upper surface 110 of the wafer 11 and sending the sucked etching liquid 400 to the upper surface 110 of the wafer 11, impurities are mixed into the etching liquid 400 and the etching liquid 400 may become contaminated. Therefore, after repeating the suction and delivery of the etching liquid 400 a predetermined number of times, the etching liquid 400 is replaced with a new one and then restarted.
Note that the etching solution 400 that has not been used repeatedly a predetermined number of times may be stored in the storage chamber 410 and waited until the next etching starts, and then used in the next etching.

4 Cleaning Step After etching the upper surface 110 of the wafer 11, the upper surface 110 of the wafer 11 is cleaned. Therefore, first, the wafer support 3 is removed from the etching liquid bottle 91 and attached to the cleaning liquid bottle 92, as shown in FIG.

Here, the cleaning liquid bottle 92 is configured similarly to the etching liquid bottle 91. The cleaning liquid bottle 92 has an opening 921 .

After the wafer support 3 is attached to the cleaning liquid bottle 92, the etching liquid nozzle 40 is moved away from above the wafer 11, and then a cleaning liquid supply process is performed. In the cleaning liquid supply step, the cleaning liquid 500 is supplied to the upper surface 110 of the wafer 11 from a cleaning liquid source (not shown), and the cleaning liquid 500 is accumulated on the upper surface 110 of the wafer 11 .

Of the cleaning liquid 500 supplied from the cleaning liquid source to the upper surface 110 of the wafer 11 , that which overflows from the upper surface 110 of the wafer 11 is collected inside the cleaning liquid bottle 92 .

Next, as shown in FIG. 6, the cleaning liquid nozzle 50 connected to the cleaning liquid suction pump 52 is positioned above the wafer 11 so that the tip 53 of the cleaning liquid nozzle 50 touches the cleaning liquid 500 supplied to the upper surface 110 of the wafer 11. Leave it in a liquid state.

Here, the cleaning liquid nozzle 50 and the cleaning liquid suction pump 52 are configured similarly to the etching liquid nozzle 40 and the etching liquid suction pump 42.
The cleaning liquid suction pump 52 is, for example, an air cylinder mechanism including a cylinder 521 and a piston 522 disposed inside the cylinder 521, and the piston 522 is connected to a suction source (not shown). Further, a space formed by the lower surface and side surface of the cylinder 521 and the lower surface of the piston 522 is a storage chamber 510 that can contain the cleaning liquid 500.

A cleaning liquid nozzle 50 connected to a cleaning liquid suction pump 52 is positioned above the wafer 11, and with the tip 53 of the cleaning liquid nozzle 50 in contact with the cleaning liquid 500 accumulated on the upper surface 110 of the wafer 11, the cleaning liquid is The cleaning liquid 500 stored on the upper surface 110 of the wafer 11 is sucked out using the suction pump 52 .

Specifically, the upper surface of the piston 522 is sucked using a suction source (not shown) connected to the piston 522, and the upper surface of the piston 522 is pulled up in the +Z direction. Then, the pressure inside the storage chamber 510 becomes negative pressure, and a suction force is generated in the storage chamber 510, and the generated suction force is transmitted to the cleaning liquid nozzle 50. As a result, the cleaning liquid 500 deposited on the upper surface 110 of the wafer 11 is sucked in from the cleaning liquid nozzle 50 and accommodated in the storage chamber 510.

Next, using the cleaning liquid suction pump 52, the cleaning liquid 500 sucked into the storage chamber 510 of the cleaning liquid suction pump 52 is returned to the upper surface 110 of the wafer 11.

Specifically, the suction source is stopped and the suction force acting on the piston 522 is removed. Then, for example, the piston 522 descends in the -Z direction due to its own weight, and the cleaning liquid 500 contained in the storage chamber 510 receives a pressing load from the piston 522 and is pushed out of the storage chamber 510, passing through the cleaning liquid nozzle 50 and spraying the wafer. 11.

In this way, using the cleaning liquid suction pump 52, sucking up the cleaning liquid 500 accumulated on the upper surface 110 of the wafer 11 and returning the sucked cleaning liquid 500 to the upper surface 110 of the wafer 11 are repeated. This causes the cleaning liquid 500 to flow on the top surface 110 of the wafer 11, and the top surface 110 is cleaned.

Note that when supplying the cleaning liquid 500 to the upper surface 110 of the wafer 11, a cleaning liquid supply source (not shown) is connected to the cleaning liquid nozzle 50, and the cleaning liquid 500 is supplied from the cleaning liquid supply source to the upper surface 110 of the wafer 11. Alternatively, an appropriate amount of cleaning liquid 500 may be stored in advance in the storage chamber 510 of the cleaning liquid suction pump 52, and the cleaning liquid 500 may be supplied to the upper surface 110 of the wafer 11.
Note that the cleaning liquid 500 is replaced with a new cleaning liquid 500 for each wafer 11. Therefore, when cleaning is not being performed, the storage chamber 510 either stores an appropriate amount of new cleaning liquid 500 or is left empty.

5 Mask Removal Step After cleaning the upper surface 110 of the wafer 11, the mask formed on the upper surface 110 of the wafer 11 is removed.
First, the wafer support 3 is removed from the cleaning liquid bottle 92 and attached to the mask removal liquid bottle 93, as shown in FIG.

Here, the mask removal liquid bottle 93 is configured similarly to the etching liquid bottle 91. The mask removal liquid bottle 93 has an opening 931.

After the wafer support 3 is attached to the mask removal liquid bottle 93, the first liquid 601 is supplied to the upper surface 110 of the wafer 11 from a first liquid source (not shown). The first liquid 601 is an alcohol-based mask removal liquid.
When the first liquid 601 is supplied to the upper surface 110 of the wafer 11 , the first liquid 601 is accumulated on the upper surface 110 of the wafer 11 due to surface tension acting on the upper surface 110 of the wafer 11 .

Note that, of the first liquid 601 supplied to the upper surface 110 of the wafer 11, that which overflows from the outer peripheral edge of the wafer 11 is collected inside the mask removal liquid bottle 93.

After supplying the first liquid 601 to the upper surface 110 of the wafer 11, the first liquid nozzle 615 is positioned above the wafer 11.

Here, the first liquid suction pump 61 is connected to the first liquid nozzle 615.
The first liquid nozzle 615 and the first liquid suction pump 61 are configured similarly to the etching liquid nozzle 40 and the etching liquid suction pump 42. The first liquid suction pump 61 is, for example, an air cylinder mechanism including a cylinder 611 and a piston 612 disposed inside the cylinder 611, and the piston 612 is connected to a suction source (not shown).

By positioning the first liquid nozzle 615 above the wafer 11 while the first liquid 601 is being supplied to the upper surface 110 of the wafer 11, the tip 616 of the first liquid nozzle 615 supplies the upper surface 110 of the wafer 11. The liquid is applied to the first liquid 601.

Next, the first liquid 601 accumulated on the upper surface 110 of the wafer 11 is sucked using the first liquid suction pump 61 .

Specifically, the upper surface of the piston 612 is sucked using a suction source (not shown) connected to the piston 612, and the upper surface of the piston 612 is pulled up in the +Z direction. Then, the pressure inside the storage chamber 610 becomes negative pressure, and a suction force is generated in the storage chamber 610, and the generated suction force is transmitted to the first liquid nozzle 615. As a result, the first liquid 601 deposited on the upper surface 110 of the wafer 11 is sucked through the first liquid nozzle 615 and accommodated in the storage chamber 610.

Moisture on the upper surface 110 of the wafer 11 is removed by supplying the first liquid 601 to the upper surface 110 of the wafer 11 and removing it by suction.

Next, the first liquid nozzle 615 is separated from above the wafer 11. Then, a second liquid 602 is supplied to the upper surface 110 of the wafer 11 from a second liquid source (not shown). The second liquid 602 is a type of mask removal liquid, and is, for example, acetone.
When the second liquid 602 is supplied to the upper surface 110 of the wafer 11 , the second liquid 602 is accumulated on the upper surface 110 of the wafer 11 due to surface tension acting on the upper surface 110 of the wafer 11 .

Note that, of the second liquid 602 supplied to the upper surface 110 of the wafer 11, the liquid that overflows from the upper surface 110 of the wafer 11 is collected inside the mask removal liquid bottle 93.

After supplying the second liquid 602 to the upper surface 110 of the wafer 11, the second liquid nozzle 625 is positioned above the wafer 11.

Here, the second liquid suction pump 62 is connected to the second liquid nozzle 625. The second liquid nozzle 625 and the second liquid suction pump 62 are configured similarly to the etching liquid nozzle 40 and the etching liquid suction pump 42. The second liquid suction pump 62 is, for example, an air cylinder mechanism including a cylinder 621 and a piston 622 disposed inside the cylinder 621, and the piston 622 is connected to a suction source (not shown).

By positioning the second liquid nozzle 625 above the wafer 11 while the second liquid 602 is stored on the upper surface 110 of the wafer 11, the tip 626 of the second liquid nozzle 625 supplies the second liquid 602 to the upper surface 110 of the wafer 11. The liquid is applied to the second liquid 602.

Next, the second liquid 602 stored on the upper surface 110 of the wafer 11 is sucked out using the second liquid suction pump 62 .
Specifically, the upper surface of the piston 622 is sucked using a suction source (not shown) connected to the piston 622, and the upper surface of the piston 622 is pulled up in the +Z direction. Then, the pressure inside the storage chamber 620 becomes negative pressure, and a suction force is generated in the storage chamber 620, and the generated suction force is transmitted to the second liquid nozzle 625. As a result, the second liquid 602 deposited on the upper surface 110 of the wafer 11 is sucked through the second liquid nozzle 625 and accommodated in the storage chamber 620.

Further, the suction source is stopped and the suction force acting on the piston 622 is removed. As a result, the piston 622 descends in the -Z direction due to its own weight, and the second liquid 602 contained in the storage chamber 620 receives a pressing load from the piston 622 and is pushed out of the storage chamber 620. In this way, the second liquid 602 contained in the storage chamber 620 is returned to the upper surface 110 of the wafer 11 through the second liquid nozzle 625.

By repeatedly supplying and sucking the second liquid 602 using the second liquid suction pump 62, a flow of the second liquid 602 is generated on the upper surface 110 of the wafer 11, and a liquid is formed on the upper surface 110. Mask is removed.

Note that if the second liquid 602 accumulated on the upper surface 110 of the wafer 11 is repeatedly sucked up and the sucked second liquid 602 is sent to the upper surface 110 of the wafer 11, impurities may be mixed into the second liquid 602. May be contaminated. Therefore, after repeating the suction and delivery of the second liquid 602 a predetermined number of times, the second liquid 602 is replaced with a new one, and then the suction and delivery of the second liquid 602 is restarted.
Note that the second liquid 602 that has not been used repeatedly a predetermined number of times may be stored in the storage chamber 620 and waited until the next mask removal starts, and may be used in the next mask removal.

6 Drying Process Finally, the wafer 11 is dried using the drying apparatus 8 shown in FIG.

The drying device 8 includes a holding table 80, a rotating means 87 for rotating the holding table 80, and a connecting member 86 for connecting the holding table 80 and the rotating means 87.

The holding table 80 includes a suction section 82 and a frame 81 that supports the suction section 82. The frame body 81 is formed to have a smaller diameter than the inner frame portion 340 of the wafer support 3 shown in FIG. The upper surface of the suction section 82 is a holding surface 820 that holds the wafer 11, and the holding surface 820 is formed flush with the upper surface 810 of the frame 81. Further, the suction section 82 is connected to a suction source (not shown).

The holding table 80 is surrounded by an annular bottom plate 84 . The holding surface 820 and the upper surface 810 of the frame body 81 are arranged at a height higher than the upper surface 840 of the bottom plate 84.

As shown in FIG. 10, a plurality of pairs of support columns 85 are erected on the upper surface of the bottom plate 84. As shown in FIG. The support column pair 85 is formed from two support columns 850. The legs 31 of the wafer support 3 can be sandwiched between the two support columns 850.

When drying the wafer 11, the wafer support 3 is first removed from the mask removal liquid bottle 93 shown in FIG.
Then, as shown in FIG. 9, the wafer support 3 supporting the wafer 11 is placed on the holding table 80. As a result, the holding table 80 penetrates the inner frame 340 of the wafer support 3, the wafer 11 is supported on the holding surface 820, and the lower surface of the main body 30 of the wafer support 3 is brought into contact with the upper surface 840 of the bottom plate 84. Supported.
At this time, as shown in FIG. 10, the legs 31 of the wafer support 3 are inserted between the two support columns 850 to fix the wafer support 3.

With the wafer 11 placed on the holding surface 820, a suction means (not shown) connected to the suction section 82 of the holding table 80 is operated to suction the wafer 11 placed on the suction section 82. . As a result, the wafer 11 placed on the holding surface 820 of the suction section 82 is suction-held onto the holding surface 820.

In this state, the holding table 80 is rotated using the rotating means 87. As a result, the wafer 11 held on the holding surface 820 rotates, and the liquid remaining on the upper surface 110 of the wafer 11 (for example, the first liquid 601 and the second liquid 602) is vaporized, and the wafer 11 is Top surface 110 is dried.

As described above, when etching the wafer 11, the etching liquid suction pump 42 is used to suck up the etching liquid 400 accumulated on the upper surface 110 of the wafer 11, and the etching liquid 400 that has been sucked out is supplied again to the upper surface 110 of the wafer 11. By doing so, the etching rate can be increased. Further, scattering of the etching liquid 400 can be suppressed. Furthermore, the use of the etching solution 400 can be reduced.
When cleaning the wafer 11, the cleaning liquid suction pump 52 is used to repeatedly suck and supply the cleaning liquid 500, thereby increasing the cleaning speed and shortening the time required to clean the wafer 11. Further, it is possible to suppress the cleaning liquid 500 from scattering. Furthermore, the amount of cleaning liquid 500 can be saved.
When removing the mask from the wafer 11, the second liquid suction pump 62 is used to repeatedly suck and supply the second liquid 602, thereby increasing the mask removal speed and shortening the time required to remove the mask from the wafer 11. Further, it is possible to suppress the second liquid 602 from scattering. Furthermore, the second liquid 602 can be omitted.

When the chemical liquid such as the etching liquid 400 is suppressed from scattering from the upper surface 110 of the wafer 11, it is not necessary to provide a cover for preventing chemical liquid scattering on the wafer support 3, the etching liquid bottle 91, etc. The device can be made more compact.

11: Wafer 110: Upper surface 3: Wafer support 30: Main body 31: Feet 32: Fastener 33: Ring portion 34: Base portion 35: Support column 340: Inner frame portion 341: Connecting portion 342: Outer frame portion 343: Hole Part 40: Etching liquid nozzle 400: Etching liquid 41: Etching liquid supply source 42: Etching liquid suction pump 410: Accommodation chamber 421: Cylinder 422: Piston 43: Tip 50: Cleaning liquid nozzle 500: Cleaning liquid 52: Cleaning liquid suction pump 510: Accommodation Chamber 521: Cylinder 522: Piston 53: Tip 61: First liquid suction pump 601: First liquid 602: Second liquid 610: Storage chamber 611: Cylinder 612: Piston 615: First liquid nozzle 616: Tip 620: Storage chamber 62: Second liquid suction pump 621: Cylinder 622: Piston 625: Second liquid nozzle 626: Tip 8: Drying device 80: Holding table 81: Frame body 810: Top surface 82: Suction part 820: Holding surface 84: Bottom plate 840: Upper surface 85: Support column pair 850: Support column 86: Connecting member 87: Rotating means 91: Etching liquid bottle 910: Upper surface 911: Opening 92: Cleaning liquid bottle 921: Opening 93: Mask removal liquid bottle 931: Opening

Claims (3)

A wet etching method for etching the upper surface of a wafer using an etching solution,
an etching solution supply step of collecting the etching solution on the upper surface of the wafer due to surface tension;
Using an etching liquid suction pump that communicates with a nozzle whose tip is immersed in the etching liquid stored on the top surface of the wafer and is capable of suctioning the etching liquid stored on the top surface of the wafer, it is applied to the top surface of the wafer using surface tension. Sucking up the accumulated etching solution and returning the sucked up etching solution from the etching solution suction pump to the upper surface of the wafer are repeated to generate a flow of the etching solution on the upper surface of the wafer, thereby etching the upper surface of the wafer. etching process and
a cleaning step of cleaning the top surface of the wafer after the etching step;
wet etching methods including; The washing step is
A cleaning liquid supply process that collects the cleaning liquid on the top surface of the wafer due to surface tension;
Using a cleaning liquid suction pump that communicates with a nozzle whose tip is immersed in the cleaning liquid accumulated on the upper surface of the wafer and is capable of sucking the cleaning liquid accumulated on the upper surface of the wafer, the cleaning liquid accumulated on the upper surface of the wafer due to surface tension is used. Repeating sucking up the cleaning liquid and returning the sucked cleaning liquid from the cleaning liquid suction pump to the upper surface of the wafer to generate a flow of the cleaning liquid on the upper surface of the wafer .
The wet etching method according to claim 1. After the cleaning step, a mask removing step of removing a mask formed on the upper surface of the wafer is included,
The mask removal step is
a mask removal liquid supply step in which the mask removal liquid is accumulated on the upper surface of the wafer due to surface tension;
Using a mask removal liquid suction pump that communicates with a nozzle whose tip is immersed in the mask removal liquid stored on the top surface of the wafer and is capable of suctioning the mask removal liquid stored on the top surface of the wafer, the wafer is removed by surface tension. The flow of the mask removing liquid on the upper surface of the wafer is repeated by sucking up the mask removing liquid accumulated on the upper surface and returning the sucked mask removing liquid to the upper surface of the wafer from the mask removing liquid suction pump. cause
The wet etching method according to claim 1.

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