JPH11111822A - Wafer-chucking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer-chucking device for applying chemical solution uniformly to the rear face of a wafer. SOLUTION: A wafer-chucking device 1 has a solution container 20. A solution (LQ) made of a chemical is stored in the solution container 20. A chucking main member 10 made up of a floating and sinking member 12 and a clip pin 30 is put in the solution (LQ). The chucking main member 10 is movable vertically by controlling the quantity of air in an air-accumulating part 16 formed in the floating and sinking member 12. When the chucking main member 10 is raised and a wafer (W) comes out of the solution (LQ), the wafer (W) is released from the clip pins 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer chuck device, and more particularly, to a wafer chuck device for performing wet processing of a wafer in a single wafer manner.

[0002]

2. Description of the Related Art FIGS. 8 to 10 show a conventional mechanical chuck type wafer chuck apparatus. Among these figures, FIG. 8 is a plan view of a conventional wafer chuck apparatus, and is a view showing the mounted wafer through. FIG.
Is a sectional view of the same, and FIG. 10 is an enlarged perspective view of the clamp pin.

As can be seen from FIG. 8, a wafer W is held by clamp pins 70 in the wafer chuck device. The wafer chuck device includes a rotating ring 7
2 is provided. The rotating ring 72 includes an inner peripheral ring 74 provided on the center side, an outer peripheral ring 76 provided on the outer peripheral side at an interval, and a connecting portion 78 connecting the inner peripheral ring 74 and the outer peripheral ring 76. And from. The rotating ring 72 is connected to the clamp shaft 80.
It is rotatable around.

The outer peripheral ring 76 is provided with a clamp pin 70. As can be seen from FIG. 10, a step 71 is formed on each of the clamp pins 70. The stepped portion 71 has a lower flat portion 71a and a higher flat portion 7a.
1b. The lower flat portion 71a is
The flat portion 71a faces the inner peripheral side, and the wafer W
Is listed.

[0005] Each of the clamp pins 70 has a central shaft 7.
3 is rotatable. That is, FIG.
As can be seen from each of the clamp pins 70,
The connecting lever 82 is connected.
Operates, the clamp pin 70 rotates. As can be seen from FIG. 9, these connecting levers 82 are connected to a clamp shaft 80 at the center of the wafer chuck device. The rotation of the clamp shaft 80 is transmitted to the clamp pin 70 via the connection lever 82. That is, the clamp shaft 80 is a rotation drive source of the clamp pin 70.

[0006] The wafer W is carried by the robot carrying mechanism, and is mounted inside these clamp pins 70. By rotating the clamp pins 70 with the wafer W mounted thereon, the clamp pins 70 are rotated.
Is gradually reduced, and the wafer W is positioned. That is, the step 71 of the clamp pin 70
The wafer W is positioned by holding down the outer peripheral end surface of the wafer W by means of.

[0007]

In the above-described wafer chuck device, a resin material or the like is used as a material of the clamp pins 70 in order to avoid damage to the wafer W. However, for other parts, a metal material or the like is used to secure rigidity during rotation. For this reason, there is a problem that these metal materials and the like cause heavy metal contamination on the wafer W during long-term use.

Further, since the connecting lever 82, which is a mechanism for transmitting rotation to the clamp pin 70, is located on the back side of the wafer W, a chemical solution or the like can be continuously supplied to the front surface of the wafer W, but cannot be continuously supplied to the back surface. There's a problem. That is, as can be seen from FIG.
The chemical liquid 86 can be continuously supplied by the chemical liquid nozzle 84a. On the other hand, the connecting lever 8
2, the chemical liquid 86 can be supplied only intermittently from the chemical liquid nozzle 84b. That is, the supply of the chemical liquid 86 to the back surface of the wafer W is intermittent. Therefore, the wafer W
There is a problem that the application of the chemical solution 86 on the back surface of the substrate becomes uneven. In particular, in an etching process using an etchant, the unevenness is a cause of failure of electrical characteristics, which is the most important point in quality.

In addition, when performing the chemical treatment, the chemical 86 supplied to the wafer W spreads in the outer peripheral direction of the wafer W by centrifugal force due to the rotational movement of the wafer W. For this reason,
The chemical liquid 86 jumps out of the wafer W, and the processing cup 88
Collides with and mist. In order to prevent the chemical liquid 86 from bouncing off at the time of collision, the processing cup 88 is provided with measures such as providing an inclined portion 88a at the collision portion of the chemical liquid 86. In addition, measures such as providing an exhaust device 90 for absorbing mist are taken. However, these countermeasures have a problem that the mist cannot always be removed to a sufficient extent. There is also a problem that the mist remaining in the processing cup 88 becomes a contamination source at the time of washing with water.

[0010] Further, since the sliding portion exists on the clamp shaft 80 and the like, there is a problem that the sliding portion becomes a dust generation source.

The present invention has been made in view of these problems, and an object of the present invention is to provide a wafer chuck device that can apply a chemical solution or the like uniformly and stably to the front and back surfaces of a wafer W. With the goal. Further, it is another object of the present invention to provide a clean wafer chuck device in which the generation of dust is eliminated by eliminating a sliding portion.

[0012]

In order to solve the above-mentioned problems, a wafer chuck device according to the present invention is provided with a liquid tank capable of storing a liquid, and is provided in the liquid tank and moves up and down in the liquid. A floating / sinking member, which rises by storing gas in a gas reservoir provided inside and descends by removing gas from the gas reservoir, and a floating / sinking member provided in the floating / sinking member. A plurality of clamp pins for holding or releasing an outer peripheral edge portion of the wafer, and the crank pin holds the wafer when the floating member descends and the clamp pin is submerged in the liquid. The wafer is opened when the floating member rises and the clamp pin is out of the liquid.

By doing so, the wafer is processed in the liquid in the liquid tank, and the liquid is uniformly attached to both the front and back surfaces of the wafer, so that a high-quality wafer without processing unevenness is manufactured. It was made.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a first embodiment of the present invention, the entirety of a chuck body on which a wafer is mounted is immersed in a liquid in which a liquid chemical is dissolved in a liquid tank, so that the liquid is uneven on both the front and back surfaces of the wafer. The wafer is exposed to the outside of the liquid and made detachable by controlling the buoyancy of the chuck main body while allowing the wafer to adhere to the wafer. This will be described in more detail below with reference to the drawings.

FIG. 1 is a view showing a cross section of the wafer chuck apparatus, and FIG. 2 is a view showing a plane viewed from above, omitting the liquid inside.

As can be seen from FIG. 1, the wafer chuck apparatus 1 includes a chuck body 10 and a liquid tank 20. In the liquid tank 20, a liquid LQ composed of a desired chemical liquid is stored. The entire chuck body 10 submerges in the liquid LQ.

The chuck body 10 includes a floating member 12. As can be seen from FIG. 2, the floating member 12 has a cylindrical shape. That is, the through hole 14 is formed at the center of the floating member 12. The through holes 14 allow the liquid LQ to flow up and down, activating the flow of the liquid LQ in the vicinity of the back surface of the wafer W.

On the upper side of the floating member 12, a clamp pin 3 is provided.
0 (1) to 30 (4) are provided. That is, the clamp pins 30 are provided at 90 ° intervals on the circumference of the floating
(1) to 30 (4) are provided. As can be seen from FIG. 1, these clamp pins 30 (1) to 30 (4)
Are formed with concave portions 32, respectively. The wafer W is locked in the recess 32. Clamp pin 3
The shaft 34 penetrates through the lower part of 0 (1) to 30 (4). This shaft 34 allows the clamp pin 30
(1) to (4) are rotatably mounted on the floating member 12. Clamp pins 30 (1) to 30 (4)
A space 36 which functions like a floating bag is formed in the upper part of the above. The space 36 is filled with a material having a low specific gravity. In the present embodiment, an inert gas is sealed. This space 32 allows the clamp pin 30
(1) to 30 (4) obtain buoyancy. The clamp pins 30 (1) to 30 (4) hold the wafer W by this buoyancy. That is, the clamp pin 30
The buoyancy of (1) to 30 (4) indicates that the wafer W
This force is a force that holds the outer peripheral edge of the wafer W.

The gas reservoir 1 is provided on the outer periphery of the floating member 12.
6 are formed. That is, the upper portion of the floating member 12 has a folded shape, and the gas reservoir 16 is formed so as to surround the outer periphery of the through hole 14 in the floating member 12. By changing the gas accumulation amount in the gas accumulation section 16, the floating
Buoyancy adjustment. The adjustment of the amount of accumulated gas is performed by the pump 40. That is, by supplying gas to the gas reservoir 16 by the pump 40, the floating member 12 rises, and conversely, by discharging gas from the gas reservoir 16 by the pump 40, the floating member 12 descends. Has become.

The upper part of the floating member 12 has a permanent magnet 1
8 are provided. That is, the permanent magnet 18 is embedded in the thick portion of the upper part of the floating member 12.

At the lower part of the floating member 12, a blade 19 is provided. That is, on the outer peripheral side of the floating member 12,
A plurality of blades 19 are provided at equal intervals along the vertical direction.

As can be seen from FIG. 2, the liquid tank 20 is a cylindrical member having a bottom. The inner diameter of the liquid tank 20 is slightly larger than the outer diameter of the floating member 12 in the chuck body 10 described above.

As can be seen from FIG. 1, a permanent magnet 22 is embedded in the thick portion of the upper portion of the liquid tank 20. The permanent magnet 22 is arranged so as to have a polarity that repels the permanent magnet 18 provided on the chuck body 10 described above. The chuck body 10 is positioned at the center of the liquid tank 20 by this repulsive force. That is, the position of the chuck body 10 is held by the repulsive force of the permanent magnet 18 incorporated in the chuck body 10 and the permanent magnet 22 incorporated in the liquid tank 20.

A pump 42 is provided on the lower right side of the liquid tank 20 in the figure. The pump 42 is a pump that ejects the liquid LQ, and sends the liquid LQ
By causing Q to collide, the chuck body 10 is rotated. This makes it possible to rotate the wafer W while holding it in the liquid.
The liquid LQ that collides with the blades 19 is the same liquid LQ as the liquid LQ stored in the liquid tank 20. In addition,
A gas such as an inert gas is spouted from the pump 42 and the blade 1
By hitting 9, a rotational force can be generated. That is, it is possible to rotate the floating member 12 of the chuck body 10 by colliding a liquid or a gaseous fluid with the blade 19.

Next, the operation of the wafer chuck device 1 will be described. As can be seen from FIG.
In a state where 0 is completely submerged in the liquid, the wet processing is performed on the wafer W. In this wet processing, the chuck body 10 is in a rotating state or a stationary state. That is, by controlling supply and discharge of gas by the pump 40, the chuck body 10 is controlled.
Is held in the liquid LQ, and by controlling the ejection of the pump 42, the chuck body 10 rotates or stands still. However, it can be said that the wet processing while rotating the chuck body 10 has better uniformity.

Thereafter, in order to dry the wafer W, the wafer W needs to be taken out of the liquid and exposed. Therefore, as can be seen from FIG.
To supply the gas to the air reservoir 16 to float the chuck body 10. When the chuck body 10 floats, the wafer W reaches above the liquid level L1. The height of the floating is determined by the distance between the wafer W and the clamp pins 30.
The heights (1) to 30 (4) do not protrude from the upper side of the liquid tank 20. That is, the clamp pins 30 (1) to
The upper end of (4) is a height that does not become higher than the height L2 of the upper end of the liquid tank 20. At this time, the clamp pins 30 (1) to 30 (4) are still holding the wafer W. This is because the space 36 is still located in the liquid LQ.

The pump 42 is driven while the wafer W is in the atmosphere. Then, the chuck body 1
0 starts rotation, and accordingly, the wafer W also rotates. The liquid LQ adhering to the wafer W by this rotation
Protrudes outward in the circumferential direction to cut off the liquid LQ on the wafer W. That is, the wafer W can be dried. The liquid LQ that has popped out at this time is:
It collides with the inside of the side wall of the liquid tank 20. Therefore, the liquid LQ
Does not scatter outside the liquid tank 20.

Next, when the wafer W is transferred to the chuck body 10, as shown in FIG. 4, the chuck body 10 is further raised. That is, the pump 40 is driven in the same manner as described above, and the gas is further supplied to the air reservoir 16, so that the chuck body 10
Is raised further. At this time, the height of the chuck body 10 is such that the wafer W comes out of the liquid tank 20. That is, the chuck main body 10 is raised so that the wafer W is higher than the height L2 of the upper end of the liquid tank 20.

At this time, the clamp pins 30 (1) to 30 (1) to 30
(4) rotates, and the attachment / detachment of the wafer W becomes possible. That is, when the chuck body 10 is raised, the clamp pins 30 (1) to 30 (4) become higher than the liquid level L1. Thus, the clamp pins 30 (1) to 30 (1) to 30
When (4) comes out of the liquid LQ, these clamp pins 3
The buoyancy of 0 (1) to 30 (4) becomes zero. That is, the space 36 does not serve as a floating bag. For this reason, the clamp pins 30 (1) to 30 (4) rotate by the weight of the upper portion, and the clamp pins are released.

On the other hand, when the wafer W is held in the liquid LQ by lowering the chuck body 10, the gas in the gas reservoir 16 is exhausted. That is, as can be seen from FIG. 4, the wafer W is set on the chuck body 10 and the gas in the gas reservoir 16 is evacuated. Then, as can be seen from FIG. 1, the chuck body 10 descends. At this time, the clamp pins 30 (1) to 30 (4) gradually close due to the buoyancy described above, and are in a state of holding the wafer W. This makes it possible to hold the wafer W in the liquid LQ.

Table 1 summarizes the relationship between the operation contents described above and the state of the chuck body 10.

[0032]

[Table 1] As described above, according to the present embodiment, since the processing of the wafer W is performed in the liquid LQ, it is possible to manufacture the wafer W without processing unevenness such as a chemical solution. That is,
Since the single-wafer wet processing is performed in the liquid, a chemical solution or the like can be uniformly attached not only on the front surface but also on the rear surface of the wafer W, and a high quality wafer W without processing unevenness can be obtained.
Can be manufactured.

Further, since a sliding portion such as a rotating shaft in the chuck body 10 can be eliminated, extremely clean processing can be performed. That is, generation of dust due to the presence of the sliding portion can be eliminated.

Moreover, since the chuck body 10 rotates while sinking in the liquid LQ, the chuck body 10 does not need to be as rigid as the conventional one. Therefore, the chuck main body 10 can be made of a non-metallic material, and contamination of the wafer W by heavy metals or the like can be prevented.

Further, the chuck body 10 can be rotated in a non-contact state with the liquid tank 20 by the repulsive force of the permanent magnet 18 embedded in the chuck body 10 and the permanent magnet 22 embedded in the liquid tank 20. . In addition, the rotation allows the liquid LQ in the liquid tank 20 to be stirred.

(Second Embodiment) In a second embodiment of the present invention, the ring-shaped liquid tank in the above-described first embodiment is modified into two guide-shaped liquid tanks provided in parallel. Thereby, the wafer W can be transferred and moved in or on the liquid. This will be described in more detail with reference to FIG.

FIG. 5 is a plan view of a wafer chuck device according to the second embodiment. In FIG. 5, a liquid in which a chemical solution or the like is mixed is omitted. As can be seen from FIG. 5, the liquid tank 50 is composed of two parallel guides 52. That is, in the above-described first embodiment, the liquid tank 20 is formed in a ring shape, but in the present embodiment, the liquid tank 50 is formed in a gutter shape. Two guides 5
A plurality of permanent magnets 54 are buried in 2 and 52, respectively. The permanent magnet 54 is connected to the floating member 12 described above.
Are disposed so as to repel the permanent magnet 18 buried therein. The chuck body 10 moves at the center position of the liquid tank 50 by the permanent magnet 54 and the permanent magnet 18. That is, the chuck body 10 is
It moves in a non-contact state. The other points are configured in the same manner as in the first embodiment, and a detailed description thereof will be omitted here.

As described above, according to the second embodiment, since the liquid tank 50 is formed in a gutter shape, the position of the chuck body 10 during rotation of the chuck body 10 in or on the liquid is not changed. The chuck body 10 can be transported and moved. For example, by creating a flow in the liquid LQ in the liquid tank 50, the chuck body 10 can be transported on this flow. Thereby, the wafer W held by the chuck body 10 can be transferred. With this configuration, a complicated and expensive transfer mechanism for the wafer W is not required, and an inexpensive system configuration can be realized.

In the present embodiment, the chuck body 10 can be moved while rotating by driving the pump 42 described above. That is, simultaneous operation of rotation and movement can be performed as a composite operation.

(Third Embodiment) A third embodiment of the present invention is an application example using the wafer chuck apparatus according to the first embodiment described above, and it is possible to simultaneously ultrasonically clean both surfaces of a wafer. This was used as an ultrasonic cleaning device. This will be described in more detail with reference to FIG.

As can be seen from FIG. 6, the third embodiment is
Applying the wafer chuck device according to the first embodiment,
This was used as an ultrasonic cleaning device. That is,
An ultrasonic vibrator 60 is provided on the liquid bottom side of the ring-shaped liquid tank 20. An ultrasonic vibration nozzle 62 is provided above the liquid surface.

With this configuration, the front and back surfaces of the wafer W can be simultaneously subjected to ultrasonic cleaning.

(Fourth Embodiment) In a fourth embodiment of the present invention, a liquid exchange mechanism for exchanging the liquid stored in the liquid tank is provided in the wafer chuck device of the first embodiment described above. This is a single processing tank type processing process in which a plurality of chemical solutions are processed.

Table 2 summarizes the contents of this processing process.

[0045]

[Table 2] As can be seen from Table 2, in step 1, the wafer W is delivered. That is, the chuck body 1
0 is raised to the highest position, and the processed wafer W
And the wafer W before processing is mounted. At this time, the liquid LQ in the liquid tank 20 is changed from pure water to the chemical liquid A.

Next, in step 2, a chemical treatment is performed. That is, the chuck body 10 is sunk to the lowest position and immersed in the liquid LQ. Thereby, the wafer W can be treated with the chemical solution A. As can be seen from the above description, in this chemical treatment, the chuck body 10 can be rotated,
You can also not rotate.

Next, in step 3, dilution and pure water treatment are performed. That is, the liquid LQ in the liquid tank 20 is changed from the chemical solution A to pure water. At this time, the height of the chuck body 10 is unchanged. That is, it is held in the liquid LQ.

Next, in step 4, the chemical treatment is performed again. That is, the liquid LQ is replaced with the chemical solution B from pure water. Also at this time, the chuck body 10 is held in the liquid LQ. Here, various chemicals can be used for the liquids A and B. Considering RCA cleaning as a typical example, a mixed solution of sulfuric acid and hydrogen peroxide solution, a mixed solution of ammonia water and hydrogen peroxide solution, a mixed solution of hydrochloric acid and hydrogen peroxide solution, or a dilute hydrofluoric acid solution can be given. Can be In addition, ozone water, ion water, and the like are also conceivable.

Next, in step 5, dilution and pure water treatment are performed again. That is, the liquid LQ in the liquid tank 20 is changed from the chemical solution B to pure water. Also at this time, the chuck body 10 is held in the liquid LQ.

Next, in step 6, the wafer W is dried. That is, as shown in FIG. 3, the chuck main body 10 is slightly lifted above the liquid level L1 and rotated. The wafer W is dried by this rotation. Thus, one process is completed, and the processes from step 1 described above are repeated. In this embodiment, the case of the process using two types of chemicals, ie, chemicals A and B, has been described. However, one type, three types, four types, etc. may be used. In the above-mentioned chemical solution treatment and pure water treatment, M
Simultaneous cleaning with ultrasonic waves in the Hz band can also be performed.

As described above, according to the fourth embodiment of the present invention, by replacing the liquid LQ in the liquid tank 20,
The wafer chuck apparatus 1 shown in FIG. 1 enables processing using a chemical solution and cleaning processing using pure water. Moreover, the liquid L
By replacing Q with a different chemical solution, the wafer W can be treated with a plurality of chemical solutions. Further, in the chemical liquid processing in steps 2 and 4, since the wafer W is in the liquid LQ, even if the wafer W is rotated, the problem that the chemical liquid is mist and scatters can be eliminated. The wafer W is rotated when drying is performed in Step 6, but since pure water is attached to the wafer W at that time, there is no problem of slight mist formation.

(Fifth Embodiment) In a fifth embodiment of the present invention, the liquid tank of the above-described second embodiment is formed in a donut shape so that wafers can be circulated, and the liquid tank is formed by a plurality of shutters. This is a multi-processing tank type processing process in which a plurality of chemical liquids can be processed by being divided into sub liquid tanks.

FIG. 7 is a view showing a wafer chuck device according to the fifth embodiment. Table 3 summarizes the contents of this processing process in a table.

[0054]

[Table 3] As shown in FIG. 7, the wafer chuck device 1 according to the present embodiment includes a donut-shaped liquid tank 50.
The liquid tank 50 has a plurality of shutters ST. In this embodiment, four shutters ST are provided, thereby forming four sub-liquid tanks. Then, the chuck body 10 circulates clockwise in the liquid tank 50.

As can be seen from Table 3, in step 1, the wafer W is delivered. That is, the chuck body 10 is lifted up to the highest position, removed from the wafer W after processing, and mounted on the wafer W before processing.

Next, in step 2, the chuck body 10 is moved. That is, open the shutter ST,
The chuck body 10 is moved to the next auxiliary liquid tank, and the shutter S is moved.
Close T. In addition, along with this movement, the chuck body 1
0 is sunk to the lowest position and immersed in the liquid LQ.

Next, in step 3, a chemical treatment is performed. That is, the chemical solution A is stored in the sub-liquid tank in step 3, whereby the wafer W can be processed with the chemical solution A. As can be seen from the above description, in this chemical treatment, the chuck body 10 can be rotated or not.

Next, in step 4, the chuck body 10 is moved. That is, open the shutter ST,
The chuck body 10 is moved to the next auxiliary liquid tank, and the shutter S is moved.
Close T. During this movement, the chuck body 10
The height is unchanged. That is, it is held in the liquid LQ.

Next, in step 5, pure water treatment is performed. In other words, pure water is stored in the sub-liquid tank in step 5, so that the wafer W can be cleaned.

Next, in step 6, the chuck body 10 is moved. That is, open the shutter ST,
The chuck body 10 is moved to the next auxiliary liquid tank, and the shutter S is moved.
Close T. During this movement, the chuck body 10
The height is unchanged. That is, it is held in the liquid LQ.

Next, in step 7, the chemical solution processing is performed again. In other words, the chemical solution B is stored in the sub-liquid tank in step 7, so that the chemical solution processing can be performed.
Here, as the liquids A and B, it is possible to use various chemicals similar to those in the above-described fourth embodiment.

Next, in step 8, the chuck body 10 is moved. That is, open the shutter ST,
The chuck body 10 is moved to the next auxiliary liquid tank, and the shutter S is moved.
Close T. During this movement, the chuck body 10
The height is unchanged. That is, it is held in the liquid LQ.

Next, in step 9, pure water treatment is performed again. That is, pure water is stored in the sub-liquid tank in step 9, and thus, a cleaning process can be performed. Also during this pure water treatment, the chuck body 10 is held in the liquid LQ.

Next, in step 10, the wafer W is dried. That is, as shown in FIG. 3, the chuck main body 10 is slightly lifted above the liquid level L1 and rotated. The wafer W is dried by this rotation. Thus, one process is completed, and the processes from step 1 described above are repeated. In this embodiment, the case of the process using two types of chemicals, ie, chemicals A and B, has been described. However, one type, three types, four types, etc. may be used. In this case, the number of the shutters ST is adjusted according to the type of the required chemical solution. Simultaneous cleaning with ultrasonic waves in the MHz band is also possible in the chemical solution treatment and the pure water treatment.

As described above, according to the fifth embodiment of the present invention, the same effects as those of the above-described fourth embodiment can be obtained. That is, it becomes possible to treat the wafer W with a plurality of chemicals, and it is possible to eliminate the problem that the chemicals are mist and scatter.

Further, since the liquid tank 50 is formed in a donut shape, the chuck body 10 can be circulated and used as it is. That is, the circulating use of the chuck body 10 becomes possible. However, even if the liquid tank 50 does not have to have a donut shape, it is sufficient if a separate collecting function of the chuck body 10 is provided.

The present invention is not limited to the above embodiment, but can be variously modified. For example, the number of the clamp pins 30 is not limited to four, but may be six, eight, or the like. Further, the permanent magnets 18 and 22 are not always necessary, and may be omitted as long as the wafer W and the chuck body 10 have a structure that can withstand some impact.

[0068]

As described above, according to the wafer chuck apparatus of the present invention, since the processing of the wafer is performed in the liquid in the liquid tank, the liquid is uniformly attached to both the front and back surfaces of the wafer. And a high-quality wafer without processing unevenness can be manufactured.

[Brief description of the drawings]

FIG. 1 is a sectional view of a wafer chuck device according to a first embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a diagram for explaining the operation of the wafer chuck device when drying a wafer.

FIG. 4 is a view for explaining the operation of the wafer chuck device when a wafer is attached / detached.

FIG. 5 is a sectional view of a wafer chuck device according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a state in which the wafer chuck device according to the first embodiment of the present invention is applied as an ultrasonic cleaning device.

FIG. 7 is a plan view showing a wafer chuck device according to a fifth embodiment.

FIG. 8 is a plan view of a conventional wafer chuck device.

FIG. 9 is a sectional view of the same.

FIG. 10 is a perspective view showing a conventional clamp pin.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wafer chuck apparatus 10 Chuck main body part 12 Floating and sinking member 14 Through hole 16 Gas reservoir part 18 Permanent magnet 19 Blade 20 Liquid tank 22 Permanent magnet 30 Clamp pin 32 Depression 34 Shaft 40 Pump 42 Pump

Claims (6)

[Claims] 1. A liquid tank capable of storing a liquid, and a floating / sinking member provided in the liquid tank and capable of moving up and down in the liquid, wherein a gas reservoir provided therein is provided. An ascending and descending member, which rises by storing gas and descends by removing gas from the gas reservoir, and a plurality of clamp pins, which are provided on the ascending and descending member and hold or open the outer peripheral edge portion of the wafer; The crankpin holds the wafer when the floating member descends and the clamp pin is submerged in the liquid, and when the floating member rises and the clamp pin comes out of the liquid. A wafer chuck device, wherein the wafer is released. 2. The wafer chuck apparatus according to claim 1, further comprising a pump for supplying and exhausting gas to and from the gas reservoir. 3. The clamp pin has a space for generating buoyancy in the clamp pin. When the clamp pin is submerged in the liquid, the buoyancy is used for the wafer. 3. When the clamp pin is out of the liquid, the wafer is opened using the weight of the clamp pin itself, the wafer being opened. 2. The wafer chuck device according to item 1. 4. The floating member is provided with a blade along a vertical movement direction of the floating member, and the floating member is rotated by colliding a fluid with the blade. The wafer chuck device according to claim 1. 5. The liquid tank has a bottomed cylindrical shape, and has a liquid exchange mechanism for exchanging liquid stored in the liquid tank, and a plurality of liquids are exchanged by exchanging the liquid. The wafer chuck device according to claim 1, wherein processing by a chemical solution is possible. 6. A liquid tank in which permanent magnets are buried and the floating members are also buried in permanent magnets, and these permanent magnets are arranged in polarities repelling each other. The wafer chuck device according to claim 5, wherein: