KR20040023943A - A Wafer Cleaning Device - Google Patents

Abstract

PURPOSE: A single processor capable of simultaneously cleaning double sides of a wafer is provided to precisely control the rotation speed of the wafer by directly delivering the rotation force of a motor to a wafer chuck and by preventing a chemical supply pipe and a lower spray nozzle from being affected by the rotation during a cleaning process. CONSTITUTION: The wafer chuck fixes the circumference of the wafer(10). The wafer chuck is directly connected to a chuck drive motor(21) by a rotation axis(22) to transfer the rotation force from the lower part. Upper and lower spray nozzles(27,33) are located on and under the wafer to spray chemicals or deionized water. A chemical liquid exhaust cup is installed in the periphery of the wafer to collect and exhaust the chemicals or the deionized water that is induced according to the rotation.

Description

Single wafer cleaning device capable of simultaneous cleaning on both sides {A Wafer Cleaning Device}

The present invention relates to a single wafer cleaning apparatus that can be cleaned and dried at the same time the upper and lower portions of the wafer by the injection nozzles formed on the upper and lower portions of the wafer. More specifically, the direct drive motor and the wafer chuck by the rotating shaft formed with a cavity The present invention relates to a single wafer cleaning apparatus capable of simultaneously cleaning both sides through which a chemical liquid drainage tube can be installed through a cavity while directly transmitting rotational force.

Generally, in the semiconductor manufacturing process, deposition, etching, coating of photoresist, developing, removing asher, and the like of the insulating material and the metal material are repeated several times. Patterning) is made, and as the process progresses, foreign matters that are not completely removed by etching or removing the asher remain in the wafer. A process for removing such foreign matters is a cleaning process using deionized water or chemical.

Meanwhile, the wafer cleaning apparatus is largely divided into a batch processor and a single processor, and the batch cleaning apparatus is 25 sheets or 50 pieces at a time as shown in FIGS. 4A and 4B. A chemical bath 102, a rinse bath 103, a dry bath 104, and a dry bath of a size capable of processing a hawk are arranged in series to form a bath. The foreign material is removed while staying for a predetermined time, and the upper and lower portions of the wafer 10 are simultaneously cleaned, and at the same time, there is an advantage of processing a large capacity.

In particular, the single wafer cleaning apparatus, as shown in FIGS. 5A and 5B, moves the wafer 10 to a wafer chuck 117 (Chuck) in a small chamber 113 (Chamber) capable of processing a single wafer 10. After the fixation is performed, the chemical liquid or pure water flows through the nozzle 119 (Nozzle) from the upper portion of the wafer 10 by rotating the wafer 10 by a motor. Pure water or the like is diffused to the upper portion of the wafer 10 to remove foreign substances.There is a separate wafer direction reversing device 116 to selectively clean the upper or lower portion of the wafer 10, which is a batch cleaning device. Compared with the small size of the device and the homogeneous cleaning effect is an advantage.

In this manner, the conventional batch cleaning device is composed of a plurality of tubs 102, 103, 104, (Bath) of a size that can accommodate 25 or 50 sheets at the same time, the size of the device is very large, and the wafer ( As the large diameter of 10) increases, the size of the tank increases, and thus the size of the apparatus and the amount of the chemical liquid are increased, and at the same time, the foreign matter that is separated from the adjacent wafer 10 in the wafer 10 being cleaned in the chemical liquid tank 102 is in progress. There is a problem of reattaching.

In the conventional single wafer cleaning apparatus, the chemical dispense position is limited to one direction, so that both surfaces cannot be cleaned at the same time. When the wafer 10 is changed twice, the cleaning is necessary for cleaning. Time is doubled and workability is inferior.

Meanwhile, a method of spraying a chemical liquid in a horizontal direction to the space between the wafer 10 and the wafer chuck 117 in the lower portion of the wafer 10 may be considered as a method of simultaneously cleaning both sides, but in this case, the chemical liquid In order to be delivered to the center of the rotating wafer 10, a high injection pressure is required, and the injected chemical liquid collides with the wafer pin so that the chemical liquid is difficult to be uniformly sprayed on the lower portion of the wafer 10. It is easy to produce process defects.

Therefore, in order to perform double-sided cleaning, chemical liquids must be directly injected to the lower part of the wafer 10 to minimize defects in various processes and to increase the cleaning efficiency of the lower part of the wafer 10.

However, the injection of the chemical liquid from the bottom through the wafer chuck 117 that is connected to the rotating shaft 118 and rotated during cleaning can be very difficult to solve this problem, the Korean Patent Publication No. 2000-77317 The disclosed technology.

It describes a cleaning device having cleaning nozzles (spray nozzles) for spraying the cleaning liquid to the upper and lower portions of the wafer 10 as a device for cleaning both sides, the lower cleaning nozzle is a wafer through a pipe-shaped through hole The cylindrical pipe is connected to the wafer chuck while the wafer chuck is connected to the motor by the belt and rotates.

This technology makes it possible to clean both sides of the wafer at the same time.However, this technology has the fluctuation of the shaft and the torque and the rotational speed due to the backlash, and the corrosive chemicals are used. There is a disadvantage that the corresponding structure for preventing corrosion of various mechanical parts including a motor becomes very complicated.

Therefore, it can be said to be inadequate for use in equipment requiring precision, and the rotation speed of the cleaned wafer is further deteriorated as the belt is worn out due to continuous use, and the accuracy of the process cannot be reached. There is a problem that must be replaced after a certain period of use.

However, in this technology, the rotational force of the motor is transmitted by the permanent magnets corresponding to the ends of the upper and lower wafer chucks. When the motor is rotated at a high speed, sudden acceleration and deceleration may occur. There is a problem that can not be used in equipment that requires precision at high speed.

The present invention is to solve the problems as described above, while transmitting the rotational force of the motor directly to the wafer chuck to stabilize the cleaning of the wafer while passing through the chemical supply pipe through the cavities of the wafer chuck and the rotating shaft through the chemical solution supply pipe and the lower portion during cleaning It is an object of the present invention to provide a single wafer cleaning apparatus capable of simultaneously cleaning both sides of the nozzle which is not affected by the rotation so that the rotational speed of the wafer can be precisely controlled.

1 is a general conceptual view of a wafer cleaning apparatus according to the present invention.

2 is a front view of a wafer cleaning apparatus according to the present invention.

3 is a front view of a wafer chuck portion of the wafer cleaning apparatus according to the present invention.

4a and 4b are a perspective view and a cross-sectional view taken along line A-A of the batch cleaning device according to the prior art.

5A and 5B are a perspective view and a cross-sectional view taken along line B-B of the sheet cleaning apparatus according to the prior art.

Explanation of symbols on the main parts of the drawings

10: wafer 21: chuck drive motor

22: axis of rotation 23: wafer chuck

24: shaft cavity 25: wafer arm

26: chuck cavity 27: upper injection nozzle

28: upper nozzle arm 29: upper nozzle driving portion

30: chemical liquid drainage cup 31: chemical liquid drainage tube

32: chemical liquid exhaust pipe 33: lower part four nozzle

34: chemical liquid supply pipe 35: chemical liquid discharge passage

36: cup lift 37,38: internal and external drug injection sphere

39: chemical liquid injection hole 40: gripper

41: gripper groove 42: gripper

43: gripper jaw 44: wafer seat

45 controller 47 chemical liquid tube

48: pure water pipe 49: dry gas pipe

The present invention for achieving the above object, the wafer chuck to fix the circumference of the wafer, the rotary shaft directly connecting the wafer chuck and the chuck drive motor to transmit the rotational force of the lower side, and the upper and lower parts of the wafer so that the chemical or pure water can be injected The upper and lower partial nozzles formed at the position, and the chemical liquid drainage cup formed around the wafer to collect and discharge the chemical liquid or pure water introduced in accordance with the rotation is characterized in that it is made.

In addition, the shaft and the center of the wafer chuck is characterized in that the axial cavity and the chuck cavity are penetrated directly to each other so that the chemical liquid supply pipe is penetrated and connected to the lower part four nozzles so that the chemical is injected regardless of the rotation of the chuck drive motor.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the single wafer cleaning apparatus of the present invention includes a gripper 40 for supporting the wafer 10 to transmit the rotational force of the chuck drive motor 21 to the wafer 10. The wafer chuck 23 is connected to the lower portion through the wafer arm 25, and the upper and lower partial nozzles 27 and 33 for spraying the cleaning chemical and the pure water are disposed on the upper and lower sides of the wafer 10. The chemical liquid drainage cup 30 is formed around the wafer chuck 23 so as to be positioned and discharge and exhaust the used chemical liquid.

Therefore, the rotary shaft 22 is connected to the lower end of the wafer chuck 23 so that the rotational force transmitted to the rotary shaft 22 by the rotation of the chuck driving motor 21 is directly transmitted to the wafer chuck 23 and rotated. do.

In addition, the chuck cavity 26 is vertically formed in the center of the wafer chuck 23 so as to penetrate the wafer chuck 23 below the lower part yarn nozzle 33 so that at least one chemical liquid supply pipe 34 is connected thereto. The shaft cavity 24 is formed in the center of the rotation shaft 22 connected to the chuck driving motor 21, and the chuck cavity 26 is connected to the shaft cavity 24.

In addition, a plurality of wafer arms 25 capable of supporting the wafer 10 are connected to the upper portion of the wafer chuck 23, and the wafer seating portions 44 of the wafer arms 25 contact the wafer 10. The gripper groove 41 is formed to allow the chemical liquid to flow down during the cleaning operation while minimizing the area.

A gripper 40 is positioned at each end of the wafer arm 25, and a gripper jaw 43 having a gripper weight 42 is formed at an end of the gripper 40.

In addition, when the rotation of the wafer chuck 23 is stopped, that is, when the wafer 10 is being conveyed, the gripper jaw 43 is opened while the gripper weight 42 is directed downward, and the wafer chuck 23 is being rotated. That is, during the cleaning operation, the gripper jaw 43 is pushed down by the centrifugal force toward the outside of the wafer chuck 23 so that the wafer 10 is supported without any mechanical device. It is fixed.

Meanwhile, the lower partial nozzle 33 and the chemical liquid supply pipe 34 are separated from the wafer chuck 23 and the rotating shaft 22 so that the lower chuck 23 is rotated by the chuck driving motor 21. ) Can be injected in a fixed position.

In addition, the chemical liquid supply pipe 34 connected to the lower part nozzle (33) is divided into chemical liquid, pure water and dry gas pipe (not shown), the dry gas is to use a high temperature nitrogen gas capable of temperature control.

In addition, as shown in FIG. 5, the lower partial nozzle 33 has an internal chemical liquid injection port 37 in which the chemical liquid is injected from the lower part of the wafer 10 to the center, and an external chemical liquid injection port in which the chemical liquid is injected between the center and the outer shell of the wafer. 38 is connected.

As shown in FIG. 1, the upper injection nozzle 27 is positioned on the upper portion of the wafer 10, and the upper nozzle arm 28 connected to the upper injection nozzle 27 is an upper nozzle driving part 29. It is connected to the upper nozzle arm 28, the chemical liquid supply pipe 34 for supplying the chemical liquid to the upper injection nozzle 27 is connected to the upper injection nozzle (27).

In addition, the chemical liquid supply pipe 34 of the upper injection nozzle 27 is divided into a chemical liquid pipe 47, a pure water pipe 48 and a dry gas pipe 49, the dry gas is a high temperature nitrogen gas or nitrogen gas and temperature control Use a gas mixed with alcohol (IPA).

In addition, the upper nozzle driving unit 29 is configured to be capable of linear reciprocating motion and shanghai movement, thereby moving the upper injection nozzle 27 from the center of the wafer 10 to the outside of the wafer 10, and the chuck driving motor 21. Chemical liquid, pure water, or dry gas may be sprayed on the wafer 10 rotated by the whole evenly.

In addition, as shown in FIG. 1, the chemical liquid draining cup 30 has an annular chemical liquid discharge passage 35 surrounding the outside of the wafer 10 so as to reduce the possibility of a process failure caused by uneven exhaust pressure around the wafer 10. ) Is loaded up and down, and each of the chemical liquid discharge passage 35 is open to the area adjacent to the outer periphery of the wafer 10, but all the remaining parts are closed.

In addition, the chemical liquid drainage cup 30 is connected to one side of the chemical liquid drainage pipe 31 in which the chemical liquid is discharged and the chemical liquid exhaust pipe 32 in which the vaporized chemical liquid is discharged, respectively, while reducing the possibility of contamination that may occur due to the mixing of the chemical liquids. Of course, the discharge path may be set differently according to the kind of the chemical liquid sprayed on the wafer 10 to be connected to the cup elevator 36 capable of reusing and collecting and reusing the chemical liquid.

Referring to the operation of the single wafer cleaning apparatus of the present invention as shown in Figure 1 and 2, after the wafer 10 is mounted on the gripper 40, the cup linear motor (not shown) is the controller ( When driven by 45), the chemical liquid drainage cup 30 moves vertically to fit the height of the chemical liquid drainage port 39 suitable for the chemical liquid to be used to surround the outside of the wafer chuck 23.

In addition, the wafer chuck 23 connected to the rotating shaft 22 is rotated by the driving of the chuck driving motor 21, and the gripper weight 42 of the gripper 40 moves outwardly of the wafer chuck 23 by centrifugal force. The end of the gripper jaw 43 is pressed down while being directed toward the wafer 10 so that the wafer 10 rotates while being fixed to the wafer chuck 23.

In addition, when the rotation of the wafer 10 reaches the desired rotational speed, the upper nozzle linear motor (not shown) is driven by the controller 45, and the upper nozzle arm 28 is horizontally moved so that the upper injection nozzle 27 is moved. When positioned at the center of the wafer 10, the chemical liquid is injected onto the wafer 10 through the upper injection nozzle 27.

In addition, the upper injection nozzle 27 moves the chemical liquid on the wafer 10 while horizontally reciprocating from the center of the wafer 10 to the outside along the upper nozzle arm 28 by adjusting the upper nozzle linear motor (not shown). Spray it evenly.

At this time, the chemical liquid supply pipe 34 of the lower part four nozzle 33 is also opened, and the chemical liquid is injected into the lower part of the wafer 10 by the lower part four nozzle 33, and the chemical liquid is injected by the rotational force of the wafer 10. Spread evenly across the bottom of the).

In addition, the ejected chemical liquid causes a chemical reaction on the surface of the wafer 10 to clean the wafer 10. When the cleaning operation is completed, the upper nozzle chemical liquid pipe 43 and the lower part nozzle nozzle supply pipe 34 are closed to remove the chemical liquid. Supply is interrupted.

In addition, a suck-back valve (not shown in the drawing) of the upper injection nozzle 27 is operated to prevent unnecessary chemicals from falling during the movement of the upper nozzle arm 28, thereby remaining the chemical liquid at the end of the upper injection nozzle 27. Is removed.

Then, the wafer chuck 23 rotates at a high speed, and the chemical liquid on the wafer 10 is pushed out of the wafer 10 and discharged through the chemical liquid drain port 39 outside the wafer 10.

In addition, when the cleaning operation is completed, the pure liquid liquid drainage port 39 of the chemical liquid drainage cup 30 moves to match the height of the wafer 10, and the upper and lower partial nozzles 27 and 33 have a pure water pipe 48. While the water is opened, pure water is injected into upper and lower portions of the wafer 10, and a rinsing operation is performed to remove all the chemical liquid used for the cleaning operation from the wafer 10, and the pure water used for the rinsing operation is a chemical liquid drain hole 39 Is discharged through).

On the other hand, when the rinse operation is completed, the supply of pure water is stopped and the chemical liquid drain port 39 for the dry gas moves to the height of the wafer 10, and then the horizontally moved upper nozzle dry gas pipe (not shown) is opened. Dry gas is injected onto the wafer 10.

In addition, the pure water on the surface of the wafer 10 is pushed by the sprayed dry gas, and the pure water is removed from the surface of the wafer 10 when the upper injection nozzle 27 is gradually moved outward from the center of the wafer 10. The top drying process (10) is completed.

On the other hand, when the drying process is completed, the wafer chuck 23 stops rotating, and when the gripper weight 42 of the gripper 40 is directed downward by gravity, the gripper jaw 43 is out of the wafer 10, The chemical liquid drainage cup 30 is lowered to complete the washing operation.

In the wafer type wafer cleaning apparatus of the present invention as described above, since the wafer is directly driven by the motor and the wafer is washed at the front and the back, the process can be greatly shortened, and the rotational force of the motor is transmitted to the wafer without loss. Therefore, a precise cleaning operation can be made, and in particular, unlike the conventional technology of transmitting rotational force by using a belt (Belt) it is unnecessary to replace parts by wear, thereby reducing the maintenance cost of the device.

In addition, the upper nozzle drive unit is configured to linearly reciprocate and move up and down to move the upper nozzle from the center of the wafer to the outside of the wafer, and with a small amount of cleaning chemicals for the wafer rotating for the motor, Chemical liquid, pure water or dry gas can be sprayed evenly over the entire area, so a small amount of cleaning liquid can provide sufficient cleaning effect, thereby reducing the manufacturing cost of using the chemical liquid.

In addition, the discharge passage of the chemical liquid drainage cup has a spiral structure to reduce the possibility of process failure due to the fluctuations in the exhaust pressure around the wafer, and the discharge passage is loaded up and down, and connected to an elevator that can move up and down to the wafer. The discharge route can be set differently according to the type of chemicals to be sprayed, so that it is possible to reduce the possibility of contamination caused by mixing the chemicals, and to collect, purify and reuse the discharged chemicals.

Claims (5)

The wafer chuck 23 fixing the circumference of the wafer 10, the rotating shaft 22 directly connecting the wafer chuck 23 and the chuck driving motor 21 to transmit the lower rotational force, and the chemical or pure water Upper and lower partial nozzles 27 and 33 positioned on the upper and lower portions of the wafer 10 to be sprayed, and a chemical liquid drainage formed around the wafer 10 to collect and discharge the chemical or pure water introduced by rotation. Single wafer cleaning apparatus capable of simultaneous cleaning on both sides, comprising a cup (30). According to claim 1, wherein the rotating shaft 22 and the center of the wafer chuck 23, the chemical supply pipe 34 is penetrated and connected to the lower part nozzle 33, the chemical solution is irrespective of the rotation of the chuck drive motor 21 Single-sided wafer cleaning apparatus capable of simultaneous cleaning on both sides, characterized in that the axial cavity (24) and the chuck cavity (26) to be penetrated so that the injection is directly connected to each other. The lower chemical injection nozzle (37) of claim 1, wherein the lower partial injection nozzle (33) is injected from the lower portion of the wafer (10) to the center portion, and the outer chemical liquid injection hole (38) is injected between the center and the outside of the wafer (10). Single-sided wafer cleaning apparatus capable of simultaneous cleaning on both sides, characterized in that formed separately. According to claim 1, wherein the chemical liquid drainage cup 30 is a chemical liquid discharge passage 35 of the spiral structure is loaded up and down, the chemical liquid drainage pipe 32 and the chemical liquid exhaust pipe 31 for discharging the vaporized chemical liquid Single wafer cleaning apparatus capable of simultaneous cleaning on both sides characterized in that the connection is formed. The cup lift 36 of claim 1, wherein the chemical liquid draining cup 30 is movable up and down so as to match a corresponding height according to the chemical liquid, the rinse liquid, and the dry gas used to clean the wafer 10. Single wafer cleaning apparatus capable of simultaneous cleaning on both sides, characterized in that connected to.