KR20090123397A - Apparatus for cleaning wafer - Google Patents

Abstract

PURPOSE: A wafer cleaning device is provided to prevent wafer separation and damage due to the rise of a cleaning solution in a cleaning bath using a wafer separation preventing material closely attaching a plurality of upper sides of the wafers. CONSTITUTION: A cleaning bath(10) receives a cleaning solution cleansing a plurality of wafers(W). A guide(18) includes a plurality of slots receiving the wafers vertically in the bottom of the cleaning bath. A robot arm(20) moves the wafers vertically received in the guide. A plurality of chucks(30) are driven by a robot arm, support both sides of the lower part of the wafer, and grips a plurality of wafers. A wafer separation prevention material(40) closely attaches the plurality of upper sides of the wafers griped by the chucks.

Description

Wafer cleaning device {apparatus for cleaning wafer}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to semiconductor manufacturing equipment, and more particularly, to a wafer cleaning apparatus for cleaning wafers.

In general, semiconductor devices are manufactured by depositing and patterning thin films that perform various functions on the wafer surface to form various circuit geometries. The unit process for manufacturing such a semiconductor device is an impurity ion implantation step of injecting impurity ions of Group 3B (eg B) or Group 5B (eg P or As) into the semiconductor, and forming a material film on the semiconductor substrate. A thin film deposition process, an etching process for forming the material film in a predetermined pattern, and a planarization process (CMP: Chemical Mechanical Polishing) to remove the step by polishing the surface of the wafer collectively after depositing an interlayer insulating film on the wafer. The process can be divided into several unit processes such as wafer and chamber cleaning processes for removing impurities.

Accordingly, in order to manufacture a semiconductor device, the above-described various unit processes may be selectively and repeatedly performed. In this process, many contaminants are generated. Therefore, in this field, a wafer cleaning process for removing such contaminants is essentially performed along with a pre / post process.

Typically, the wafer cleaning process is a state in which a plurality of wafers are put in a cleaning tank containing a cleaning liquid for cleaning the wafers. At the bottom of the cleaning bath, a wafer guide is formed to insert and hold a plurality of wafers vertically into a plurality of slots. A robot arm for moving a plurality of wafers is formed at an upper portion of the cleaning tank, and a plurality of chucks coupled to the robot arm to hold the plurality of wafers are formed.

The plurality of chucks may be held while supporting the plurality of wafer outer peripheral surfaces facing each other to cause the robot arm to move the plurality of wafers.

However, the conventional wafer cleaning apparatus has a problem in that the production yield is reduced because the wafer may be separated from the plurality of chucks by the rise of the cleaning liquid such as bubbles generated in the cleaning tank and the wafer may be broken.

An object of the present invention for solving the above problems is to provide a wafer cleaning apparatus that can increase or maximize the production yield by preventing the wafer held by the plurality of chuck to be separated and broken.

A wafer cleaning apparatus according to an aspect of the present invention for achieving the above object, the cleaning tank for containing a cleaning liquid for cleaning a plurality of wafers; A guide in which a plurality of slots are formed to vertically receive the plurality of wafers at the bottom of the cleaning tank; A robot arm for moving the plurality of wafers received perpendicularly to the guide; A plurality of chucks driven by the robot arm and holding the plurality of wafers by supporting both sides of the lower sides of the plurality of wafers facing each other; And a wafer escape preventing body for closely contacting the upper portions of the plurality of wafers held by the plurality of chucks.

Here, the wafer departure preventing body preferably includes an adhesion bar formed in a direction crossing the top of the plurality of wafers vertically received in the slot.

According to the present invention, it is possible to prevent wafer detachment and breakage due to the rise of the cleaning liquid in the cleaning tank by using the wafer release prevention body that closely adheres the plurality of wafers held by the plurality of chucks, thereby increasing the production yield. Or you can maximize the effect.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a cross-sectional view schematically showing a wafer cleaning apparatus according to an embodiment of the present invention, Figures 2 and 3 are a perspective view and a side view showing the robot arm and the wafer departure prevention body of Figure 1, Figures 4 and 5 6 and 7 are cross-sectional views illustrating the vertical connection bar of FIG. 1, and FIGS. 8 to 11 are side views illustrating the wafer transfer process of the wafer cleaning apparatus of FIG. 1. to be.

1 to 3, the wafer cleaning apparatus of the present invention may perform the cleaning process in the cleaning tank 10 filled with the cleaning liquid 16 for cleaning the plurality of wafers W. As shown in FIG. Here, the plurality of wafers W are positioned vertically by the plurality of slots (19 in FIG. 8) formed in the guide 18 at the bottom of the cleaning tank 10.

The cleaning tank 10 is a container for storing the cleaning liquid 16. For example, the cleaning tank 10 may include a plurality of wafers W and a main cleaning tank 12 formed to sufficiently immerse the plurality of wafers W in the cleaning liquid 16, and the main cleaning tank 12. It consists of an auxiliary cleaning tank (14) for auxiliary collecting the three semen 16 overflowing. Generally, the washing tank 10 means the main washing tank 12, and the washing liquid 16 collected from the auxiliary washing tank 14 is circulated and supplied to the main washing tank 12. Although not shown, the cleaning liquid 16 circulation rod or the cleaning liquid 16 circulation line in which a plurality of injection holes for ejecting the cleaning liquid 16 is formed at the bottom of the guide 18 formed at the bottom of the main cleaning tank 12. .

 The cleaning liquid 16 is formed of a solution for removing contaminants such as organic substances caused on the surfaces of the plurality of wafers W introduced into the cleaning tank 10 or etching a thin film having a predetermined thickness formed on the plurality of wafers W. . For example, the cleaning liquid 16 includes a strong acid such as sulfuric acid, nitric acid, hydrofluoric acid, or the like, and may further include deionized water for diluting the strong acid. When the cleaning process using the cleaning liquid 16 is completed, a plurality of wafers W are transferred to the outside of the cleaning tank 10.

Therefore, the plurality of wafers W having been cleaned in the cleaning tank 10 may be transferred to another cleaning tank 10 or a drying apparatus by the robot arm 20.

The robot arm 20 may insert the plurality of chucks 30 in the cleaning tank 10 to hold the plurality of wafers W. FIG. The robot arm 20 may hold or unhold the plurality of wafers W while rotating the plurality of chucks 30 in opposite directions. The plurality of chucks 30 may hold the plurality of wafers W by supporting both sides of the lower portions of the plurality of wafers W standing vertically while facing each other. For example, each of the plurality of chucks 30 includes a fixing bar 32 fixed to the robot arm 20, and an upper pedestal 34 and a lower pedestal supporting the plurality of wafers W at the ends of the fixing bar 32. 36). The upper pedestal 34 and the lower pedestal 36 are formed to have the same or similar position as the radius of curvature of the plurality of wafers W. As shown in FIG. Although not shown, the upper pedestal 34 and the lower pedestal 36 are provided with a plurality of grooves into which the outer circumferential surfaces of the plurality of wafers W are inserted.

Accordingly, the plurality of chucks 30 are supported by the plurality of grooves formed in the upper pedestal 34 and the lower pedestal 36 while supporting the lower portions of the plurality of wafers W standing vertically. It is possible to hold the plurality of wafers W by preventing them.

On the upper end of the plurality of wafers W supported by the plurality of chucks 30, a wafer escape preventing body 40 is formed to closely contact the plurality of wafers W. The wafer detachment prevention body 40 may prevent the wafer W from jumping upward as the upper surface of the plurality of disk-shaped wafers W closely adheres toward the plurality of chucks 30. In particular, when the wafer escape preventing body 40 is to hold and move the plurality of wafers W by using the plurality of chucks 30 in the cleaning tank 10 filled with the cleaning liquid 16, the cleaning liquid ( The wafer W may be lifted by a large amount of bubbles generated at 16 and may be prevented from falling out of the plurality of chucks 30 and falling to one side. Since the anti-wafer release body 40 may be immersed in or close to the cleaning solution 16 contained in the cleaning bath 10, the wafer leaving prevention body 40 is coated with a Teflon material having excellent corrosion resistance from the cleaning solution 16.

 Therefore, in the wafer cleaning apparatus according to the embodiment of the present invention, the plurality of chucks 30 are attached to each other by closely contacting the upper ends of the plurality of wafers W in the direction of the plurality of chucks 30 using the wafer departure preventing body 40. The wafer W can be prevented from escaping.

For example, the wafer detachment prevention body 40 is in contact with the upper end of the plurality of wafers W, the contact bar 42 for closely contacting the plurality of wafers W to the bottom, and the contact bar 42 to the wafer W. And a connecting bar 44 positioned to match the upper end and connected to the robot arm 20. Here, the adhesion bar 42 is formed in the direction crossing the several wafer W. As shown in FIG. For example, the contact bar 42 is formed in a curved elliptical cross section having the same or similar radius of curvature as the plurality of wafers W outer peripheral surfaces while contacting the plurality of wafers W outer peripheral surfaces as shown in FIGS. 4 and 5. . In addition, the adhesion bar 42 is formed to have the same or similar length as the upper pedestal 34 and the lower pedestal 36 constituting the plurality of chucks 30 because they must be collectively contacted with the upper ends of the plurality of wafers W. . Although not shown, the contact bar 42 has a plurality of grooves into which edges of the plurality of wafers W are inserted. Here, the plurality of grooves of the contact bar 42 are formed in parallel with the plurality of grooves formed in the upper pedestal 34 and the lower pedestal 36 of the plurality of chucks 30.

As described above, the connection bar 44 is formed to position the contact bar 42 at the top center of the plurality of wafers W so that the contact bar 42 closely adheres the plurality of wafers W to the bottom. have. For example, the connection bar 44 may be mounted to the cradle 46 mounted on both sides of the robot arm 20, and the contact bar 44 may be disposed at a position corresponding to the center of the cradle 46 and the centers of the upper ends of the plurality of wafers W. And a plurality of vertical connecting bars 48 for positioning 42. Here, the holder 46 is formed to be fixed regardless of the rotation of the robot arm 20 for rotating the plurality of chuck (30). Therefore, the portion where the robot arm 20 and the cradle 46 are connected may be treated with a bearing.

The vertical connection bar 48 is formed between the holder 46 and the contact bar 42. As the contact bar 42 adheres to the upper ends of the plurality of wafers W, a predetermined level of compressive force is applied in the longitudinal direction. Is applied. In this case, when the vertical connection bar 48 is fixed in the longitudinal direction, the plurality of wafers W may be damaged. Therefore, the vertical connection bar 48 is one-dimensional restrained movement of the contact bar 42 in the vertical direction, that is, as the contact bar 42 is raised and lowered so as to press the contact bar 42 at a predetermined level of pressure. It must be formed.

The vertical connection bar 48 may be divided into a cylinder 50 or a folder 60. First, as shown in FIG. 6, the vertical connecting bar 48 in the form of a cylinder 50 is formed to vertically raise and lower the contact bar 42 by contraction and expansion of the inserted structure. In general, the cylinder 50 comprises a piston 54 and a head 52. As the piston 54 moves inside the head 52, the contact bar 42 may move together.

Of course, the directions of the head 52 and the piston 54 may be interchanged with each other. In this case, the cylinder 50 may expand while falling vertically by the load of the contact bar 42 itself, and the plurality of wafers W may be contracted while pushing up the contact bar 42. The cylinder 50 can adjust the contraction and expansion distance freely. The release preventing body does not need to adjust the contraction distance, but if it is desired to adjust the expansion distance, the contact bar 42 by using a distance adjuster 70 such as an adjustment screw inserted into the head 52 of the cylinder 50. It is possible to adjust the moving distance of.

In addition, the cylinder 50 may further provide a constant pressure in addition to the load of the contact bar 42. Various materials may be inserted into the head 52 of the cylinder 50 to adjust the adhesion pressure of the adhesion bar 42. For example, the cylinder 50 may comprise a hydraulic cylinder, an air cylinder, an electric cylinder, or a spring cylinder.

Therefore, the wafer cleaning apparatus according to the embodiment of the present invention uses the cylinder 50 to closely contact the upper part of the plurality of wafers W supported by the plurality of chucks 30 with a predetermined load or to a predetermined pressure. This can prevent the wafer W from being separated.

As shown in FIG. 7, the vertical connection bar 48 in the form of a folder 60 may repeatedly perform contraction and expansion while the structures crossing each other are folded or unfolded. The folder 60 has a plurality of vertical rivets 64, 66 when the plurality of horizontal rivets 62 facing each other are retracted, and when the plurality of horizontal rivets 62 are close, the plurality of vertical rivets 64 , 66 is formed to raise and lower the contact bar 42 while being expanded. Accordingly, the plurality of horizontal rivets 62 and the plurality of vertical rivets 64 and 66 can contract and expand exclusively with each other. Here, the upper vertical rivet 64 of the plurality of vertical rivets 64 and 66 formed in the folder 60 is coupled to the cradle 46, the lower vertical rivet 66 is coupled to the top of the contact bar 42 do.

Similarly, the lowering position of the contact bar 42 can be determined by adjusting the distance at which the horizontal rivets 62 are close. For example, the folder 60 has a horizontal rivet by installing a distance adjuster 70 such as an adjustment screw between the horizontal rivet 62 and the vertical rivets 64 and 66 or in a portion extending beyond the vertical rivets 64 and 66. The approaching distance of 62 can be limited, and the distance by which the close bar 42 descends can be adjusted. The folder 60 closely adheres the contact bars 42 to the plurality of wafers W under load. On the other hand, although not shown, the vertical movement of the contact bar 42 may be controlled by a driving device driven to adjust the distance between the plurality of horizontal rivets 62 at the upper or lower portion of the upper vertical rivet 64. .

Therefore, the wafer cleaning apparatus according to the embodiment of the present invention, the wafer escape preventing body 40 which closely adheres the upper portions of the plurality of wafers W between the holding and holding the plurality of wafers W. ) Can be used to prevent the separation and damage of the wafer (W) to increase or maximize the production yield.

On the other hand, the adhesion of the plurality of wafers (W) by the load of the adhesion bar 42 is as follows.

As shown in FIG. 8, first, when the cleaning process of the plurality of wafers W mounted on the guide 18 in the cleaning tank 10 is completed, the inside of the cleaning tank 10 is opened by the robot arm 20. A plurality of chucks 30 are inserted into the furnace. Here, the robot arm 20 may have a plurality of wafers W at the center of the plurality of chucks 30 in the cleaning tank 10 and lower the plurality of chucks 30. At this time, the vertical connection bar 48 of the wafer detachment preventing body 40 is fully inflated until it contacts the upper ends of the plurality of wafers W.

As shown in FIG. 9, the plurality of chucks 30 inserted into the cleaning tank 10 are inserted to a depth below the outer circumferential surface of the lower portion of the plurality of wafers W, and then support each of the plurality of wafers W. Getting closer. Here, the plurality of chucks 30 are lowered by the robot arm 20, and the vertical connection bar 48 is contracted after the contact bar 42 contacts the upper ends of the plurality of wafers W. As shown in FIG. When the plurality of chucks 30 is lowered, the vertical connecting bar 48 is contracted to the maximum.

As shown in FIG. 10, the robot arm 20 is raised to a set height so that the plurality of chucks 30 support the lower portions of the plurality of wafers W. As shown in FIG. As the plurality of chucks 30 are lifted by the robot arm 20, the lower portions of the plurality of wafers W are supported and closely adhered by the wafer detachment preventer 40 from the top, so that the plurality of wafers W do not fall down. Can be moved.

As shown in FIG. 11, the robot arm 20 finally moves the plurality of wafers W out of the cleaning tank 10 so that the plurality of wafers W cleaning or drying process may be subsequently performed. Can be.

As described above, in the present invention, the plurality of wafers are prevented by using the wafer escape preventing body 40 which closely contacts the plurality of wafers W at the upper end of the plurality of wafers W supported by the plurality of chucks 30. The effect of preventing the separation of two wafers W can be expected.

The wafer cleaning apparatus according to the preferred embodiment of the present invention has been described above. However, this is only one preferred embodiment presented for achieving the object of the present invention, the structure may be changed as many as possible without departing from the spirit of the present invention. For example, in the present embodiment, the wafer escape preventing body 40 has been described as being formed of the contact bar 42 and the connection bar 44. In addition to the structure, the wafer W supported by the plurality of chucks 30 is provided. A structure for bringing the wafer W into close contact with the bottom of the top may be applied.

In addition, the present embodiment has been described that the wafer leaving preventing body 40 is coated with a Teflon material, it can be made of any material having any corrosion resistance or durability to the cleaning liquid 16, of course.

The above description of the embodiments is merely given by way of example with reference to the drawings in order to provide a more thorough understanding of the present invention and should not be construed as limiting the invention. In addition, for those skilled in the art, various changes and modifications may be made without departing from the basic principles of the present invention.

1 is a cross-sectional view schematically showing a wafer cleaning apparatus according to an embodiment of the present invention.

2 and 3 are a perspective view and a side view showing the robot arm and the wafer escape prevention body of Figure 1;

4 and 5 are a cross-sectional view and a side view showing the adhesion bar of the wafer escape preventing body of FIG.

6 and 7 are cross-sectional views showing the vertical connecting bar of FIG.

8 to 11 are side views illustrating a wafer transfer process of the wafer cleaning apparatus of FIG. 1.

* Description of the symbols for the main parts of the drawings *

10: cleaning tank 20: robot arm

30: Chuck 40: Wafer departure prevention body

50: cylinder 60: folder

70: distance adjuster

Claims (11)

A cleaning tank containing a cleaning liquid for cleaning a plurality of wafers; A guide in which a plurality of slots are formed to vertically receive the plurality of wafers at the bottom of the cleaning tank; A robot arm for moving the plurality of wafers received perpendicularly to the guide; A plurality of chucks driven by the robot arm and holding the plurality of wafers by supporting both sides of the lower sides of the plurality of wafers facing each other; And And a wafer escape preventing body for closely contacting the upper portions of the plurality of wafers held by the plurality of chucks. The method of claim 1, The wafer escape preventing body includes a contact bar formed in a direction crossing the upper portion of the plurality of wafers vertically received in the slot. The method of claim 2, And the adhesion bar has an elliptic cross section bent in the same or similar shape to the outer circumferential surface of the plurality of wafers. The method of claim 2, And the adhesion bar has a plurality of grooves into which edges of the plurality of wafers are inserted. The method of claim 2, The wafer escape preventing body is coupled to the robot arm, the wafer cleaning apparatus, characterized in that it comprises a connection bar for supporting the close bar. The method of claim 5, wherein The close contact bar and the connection bar is a wafer cleaning apparatus, characterized in that the coating treatment of Teflon material. The method of claim 5, wherein The connecting bar includes a cradle coupled to the robot arm, and a vertical connecting bar supporting the close bar while being vertically connected to the fixed bar. The method of claim 7, wherein And said vertical connecting bar comprises a cylinder or a folder. The method of claim 8, And the cylinder includes a hydraulic cylinder, an air cylinder, an electric cylinder, or a spring cylinder for lifting up and down the contact bar. The method of claim 8, And the folder includes a plurality of horizontal rivets and a plurality of vertical rivets that are contracted and expanded exclusively from each other. The method of claim 7, wherein The vertical connection bar is a wafer cleaning apparatus, characterized in that it comprises a regulator for adjusting the lifting range of the close contact bar.

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