KR102111592B1 - Injection type wafer wetting device - Google Patents

Abstract

The present invention relates to a wafer wetting device used in a chemical mechanical polishing process, the holder for supporting the wafer; A liquid discharging unit for discharging and supplying liquid from the edge of the wafer to an upper surface of the wafer, but discharging the liquid at a pressure sufficient to remain on the surface of the wafer without ejecting the liquid out of the wafer; By including, by discharging the liquid from the edge of the wafer to the upper surface of the wafer at a low water pressure, the discharged pure water stays on the surface of the wafer and sequentially fills and covers the surface of the wafer, thereby maintaining the wet state of the wafer. Is not dipping in the liquid, and at the same time, while maintaining a standby state where the handler and the like can hold the wafer immediately, it can prevent the pure water from splashing out to the surroundings, thereby preventing the damage of peripheral parts and keeping the wafer wet. An injection-type wafer wetting device is provided.

Description

Spraying wafer wetting device {INJECTION TYPE WAFER WETTING DEVICE}

The present invention relates to a wafer wetting device used in connection with a chemical mechanical polishing process, and more particularly, to a wafer wetting device capable of maintaining a wafer in a wet state while the wafer cannot be dipping.

The chemical mechanical polishing (CMP) device is used for wide area planarization to remove the height difference between the cell area and the peripheral circuit area due to irregularities on the wafer surface generated by repeatedly performing masking, etching, and wiring processes during the semiconductor device manufacturing process, and for forming a circuit. This is a device used to precisely polish the surface of the wafer in order to improve the surface roughness of the wafer due to the separation of the contact/wiring film and the highly integrated device.

In such a CMP device, the carrier head presses the wafer to perform a polishing process with the polishing surface of the wafer facing the polishing pad before and after the polishing process, and at the same time, when the polishing process ends, the wafer is directly and indirectly It moves to the next process in the state of holding by vacuum adsorption.

Recently, in order to perform a more sophisticated chemical mechanical polishing process, a method in which a chemical mechanical polishing process is performed on wafers under different polishing conditions in a plurality of polishing plates has been proposed. According to the chemical mechanical polishing system according to Korean Patent Registration No. 10-1188579, a configuration in which a wafer carrier moves in a state of holding a wafer to perform chemical mechanical polishing processes step by step in a plurality of polishing plates, respectively.

On the other hand, while the chemical mechanical polishing process is performed, the polishing surface of the wafer must be kept wet, and when the polishing surface of the wafer is dried, the wafer is damaged, causing a fatal defect that cannot be used to manufacture a semiconductor device. Therefore, in a case where the chemical mechanical polishing process is performed in multiple stages on a large number of polishing plates, thorough management is required to keep the wafer wet.

On the other hand, since the wafer on which the chemical mechanical polishing process is performed on the polishing platen is supplied with any one or more of slurry and pure water, there is no problem in maintaining the wet state of the wafer. And, as proposed by the present applicant through the recent patent application No. 2013-65084, for a wafer to be moved onto a polishing platen, the wafer can be maintained in a wet state by immersing the wafer in pure water to maintain the wet state. .

However, in the loading unit for loading a wafer into a wafer carrier, or in an unloading unit in which a chemical mechanical polishing process is completed and moved to a cleaning process, there is a case where the wafer has to wait for a certain time. That is, in the loading unit and the unloading unit, the waiting time is relatively short, but the unloading unit must wait in the loading unit until the wafer is mounted on the wafer carrier or until it is separated from the wafer carrier and transported to the cleaning process by the handler. To wait on. However, if the polishing surface of the wafer is dried while the wafer is waiting in the loading unit and the unloading unit, a serious problem is caused that the wafer is damaged, and in the loading unit and the unloading unit, a handler or a wafer carrier must be able to grip the wafer. There is a limitation that the wafer cannot be immersed in pure water.

To solve this problem, similar to the wafer cleaning apparatus shown in FIGS. 1 and 2, pure water is jetted onto the surface of the wafer W held by the holder 10 from the pure water jet unit 20 (99d). ) To find a way to keep the wafer's surface wet. In the drawings, 18, which is not described, is a connection part of the holder 10, and 19, which is not shown in the figure, is a support. However, as shown in FIGS. 1 and 2, when the wafer wetting device 1 is constructed similarly to the general spraying cleaning device, the pure water spraying unit (H) at a height H of about 100 mm from the plate surface of the wafer W ( 20), in order to keep the wafer W in a wet state by dividing pure water from the pure water spraying unit 20, the pure water sprayed from the pure water spraying unit 20 is placed on the surface of the wafer W. After reaching, a problem is caused that the parts, such as a sensor that bounces around (99d') and detects whether or not the wafer w is mounted, are damaged.

Therefore, except for the dipping method in which the wafer W is immersed in pure water, the surface of the wafer W is maintained in a wet state, but it prevents moisture from reaching components such as sensors disposed around, so as not to be broken or damaged. There is a great need for a wafer wetting device.

The present invention was created under the above-mentioned technical background, and the object of the present invention is to provide a wafer wetting device capable of maintaining a wafer in a wet state without being dipping, since it must be transferred by a handler or a wafer carrier after the wafer is mounted. Is done.

At the same time, the present invention aims to keep the wafer in a wet state while preventing splash of pure water into the surroundings to prevent damage to peripheral components.

In addition, an object of the present invention is to maintain a wet state over the entire surface of the wafer mounted on the holder.

In addition, an object of the present invention is to maintain a state that can be gripped immediately by a handler or the like while maintaining the wet state of the wafer.

In order to achieve the above object, the present invention, a holder for supporting the wafer; A liquid discharging unit for discharging and supplying liquid from the edge of the wafer to an upper surface of the wafer, but discharging the liquid at a pressure sufficient to remain on the surface of the wafer without ejecting the liquid out of the wafer; It provides a wetting device for a wafer, characterized in that comprises a.

In applying the liquid to the surface of the wafer, it is not sprayed on the surface of the wafer at high pressure, but rather discharges the liquid at a low water pressure at which the liquid discharged from the edge of the wafer can stay on the surface of the wafer. This is to maintain the wet state of the wafer by covering the surface of the wafer.

Through this, while the wafer is dipping into the liquid, it does not maintain a wetting state, while a handler or the like is maintained in a standby state capable of holding the wafer immediately, while preventing liquid splashing on components such as peripheral sensors of the wafer, the surface of the wafer Will be able to remain wet.

Here, it is preferable that the liquid discharged by the liquid discharge unit is deionized water in which an unexpected chemical reaction does not occur on the surface of the wafer.

Then, the liquid discharge unit discharges pure water from the edge of the wafer, but discharges pure water at a pressure sufficient to reach the plate surface of the wafer without reaching the center of the wafer. By reaching the plate surface of the wafer at such a low water pressure, the amount of pure water collected on the plate surface of the wafer is gradually increased, thereby maintaining the wetting state of the wafer in a form in which pure water spreads over the entire surface of the wafer.

Preferably, the liquid discharge unit discharges pure water at a low water pressure as described above, but it is preferable to discharge it in a horizontal direction and supply it to the plate surface of the wafer. Through this, pure water can be supplied to the surface of the wafer more widely even at low water pressure, and it is possible to reliably prevent the pure water splashing out from the surface of the wafer.

For example, the liquid ejecting unit has a discharge port located at a low height within 30 mm from the top surface of the wafer, and discharges pure water in an approximately horizontal direction while maintaining an angle within 10 degrees with respect to the plate surface. It is possible to obtain an effect of maintaining a wet state over the entire surface of the wafer while maintaining a state in which the wafer can be gripped immediately without splashing of pure water.

The wafer wetting device configured as described above is used in any one or more of a loading unit for mounting a wafer in a chemical mechanical polishing system in which a plurality of polishing plates are subjected to a chemical mechanical polishing process and an unloading unit for transferring the wafer to a cleaning process. The wafer surface is wet while waiting for the wafer to be unloaded or loaded into the wafer carrier by a handler without damaging components such as surrounding sensors due to the fact that pure water does not splash outside to wet the wafer. Can be maintained.

The term'horizontal direction' and similar terms described in the present specification and claims not only refer to a direction forming an angle of 90 degrees to the gravitational direction, but are also defined to include all angles in a range that can be regarded as being substantially horizontal. I will do it.

According to the present invention, by discharging the liquid from the edge of the wafer to the upper surface of the wafer at a low water pressure, the discharged pure water stays on the surface of the wafer and sequentially fills and covers the surface of the wafer, thereby maintaining the wet state of the wafer, Is not dipping into the liquid, and at the same time, while maintaining a standby state where the handler and the like can hold the wafer immediately, it can prevent the pure water from splashing out to the surroundings, thereby preventing damage to the peripheral parts and keeping the wafer wet. Advantageous effects can be obtained.

1 is a perspective view showing the configuration of a typical wafer cleaning apparatus,
Figure 2 is a front view of Figure 1,
Figure 3 is a perspective view showing the configuration of a wafer wetting device according to an embodiment of the present invention,
4 is a view for explaining the discharge direction of pure water,
Figure 5 is a plan view of Figure 3,
Figure 6 is a front view of Figure 3,
Figure 7 is a perspective view showing the liquid discharge unit of Figure 3,
Fig. 8 is a longitudinal sectional view of the liquid ejecting unit of Fig. 7,
9A to 9G are photographs taken in a state according to the operation sequence of the wafer wetting device of FIG. 3.

Hereinafter, the spray type wafer wetting device 100 used in the chemical mechanical polishing process according to an embodiment of the present invention will be described in detail. However, in describing one embodiment of the present invention, the same or similar reference numerals are assigned to the same or similar configurations as the conventional configuration, and the description thereof will be omitted to clarify the gist of the present invention.

Figure 3 is a perspective view showing the configuration of a wafer wetting device according to an embodiment of the present invention, Figure 4 is a view for explaining the discharge direction of pure water, Figure 5 is a plan view of Figure 3, Figure 6 is a front view of Figure 3 , FIG. 7 is a perspective view showing the liquid ejecting unit of FIG. 3, FIG. 8 is a longitudinal sectional view of the liquid ejecting unit of FIG. 7, and FIGS. 9A to 9G are photographs of a state in accordance with the operation sequence of the wafer wetting device of FIG. It is a picture.

As shown in the drawing, the spray-type wafer wetting device 100 used in the chemical mechanical polishing process according to an embodiment of the present invention includes a holder 110 supporting the wafer W and an edge of the wafer W It is composed of a liquid discharge unit 120 to discharge the pure water 99 at a low pressure on the upper surface of the wafer W so that the upper surface of the wafer W is filled with pure water and becomes wet.

The holder 110 is formed in such a way that the wafer W is mounted on the support surface 110s to support the wafer W so that the top surface of the wafer W can be exposed. Accordingly, when the upper surface of the wafer is wetted by the pure water 99, the entire upper surface of the wafer is covered by the pure water 99.

And, the holder 110 is formed of two or more spaced apart from each other, a handler (not shown) formed as a robot arm or the like through the space of the holder 110 at any time, the wafer (W) mounted on the holder 110 Make it a state that can be gripped. That is, as shown in FIG. 3, the wafer W may be mounted by two wide support surfaces 110s, and as shown in FIG. 9A, holders are disposed at 90-degree intervals, thereby increasing the number of holders. It may be supported by mounting the wafer (W) with a small support surface.

The holder 110 may be fixed in place, but when the wafer W is seated on the holder 110, some of the holders 110 move in the left-right direction 110d so that the wafer W is the holder 110 ). Even in this case, when the side surface 110k of the holder 110 shown in FIG. 7 comes into contact with the edge of the wafer W, the wafer W is always moved by stopping the movement 110d of the holder 110. Can be mounted in a certain position.

The liquid discharge unit 120 is disposed outside the edge of the wafer W, receives pure water from the pure water supply unit 125 through the supply pipe 122, and lowers the pure water 99 on the upper surface of the wafer W. Spray with pressure. That is, when the wafer W is mounted on the holder 110, the liquid discharge unit 120 sprays pure water 99 toward the plate surface of the wafer W so that the upper surface of the wafer W is covered with pure water. .

At this time, all of the pure water 99 discharged from the liquid discharge unit 120 is controlled so that the discharge pressure is low enough to reach and stay on the plate surface of the wafer W. Preferably, the pure water discharged from the liquid discharge unit 120 is It is controlled to fall 55 to the wafer plate surface of an area not reaching the center line 88 of the wafer W shown in FIG. 4.

In addition, the liquid discharge unit 120 may be formed with one discharge port 121 for discharging pure water 99, but as shown in FIG. 3, so that the upper surface of the wafer W becomes wet within a shorter time. The pure water 99 is discharged to spread radially from the discharge port 121.

That is, in the liquid discharge unit 120, as shown in FIG. 8, a passage 120x of pure water supplied from the supply pipe 122 is formed therein, and while communicating with the passage 120x, a plurality of communication passages are formed in different directions. The discharge port 121 is provided. At this time, the spraying range between the outermost discharge ports 121 is preferable in that it does not exceed 150 degrees to prevent splashing of pure water out of the wafer W.

In addition, although not shown in FIGS. 3 and 4, as illustrated in FIG. 7, the liquid discharge unit 120 may be positioned at one side of the holder 110. Through this, it is easy to position the liquid discharge unit 120 outside the edge of the wafer W.

At the same time, the discharge direction of the pure water 99 discharged by the liquid discharge unit 120 is coincident with the horizontal surface 77 or discharged in a substantially horizontal direction with the horizontal surface 77 and an inclination angle α of 10 degrees or less. It is desirable to do. Further, even if the discharge direction of the pure water 99 discharged from the liquid discharge unit 120 is sprayed in a direction coinciding with the horizontal surface 77, the discharge pressure of the pure water 99 is low, so the dropping point 55 is the wafer ( The pure water discharged to the wafer W by the discharge pressure does not splash outside without leaving the upper surface of W).

Through this, even if the discharge pressure of the pure water 99 discharged from the liquid discharge unit 120 is adjusted low, the pure water dropped on the plate surface of the wafer W is not spread by the discharge pressure, but is discharged thereafter and discharged from the wafer. It is pushed by the pure water falling on the plate surface and spreads over the entire plate surface of the wafer W, so that the entire plate surface of the wafer W becomes wet.

That is, when pure water starts to be discharged from the liquid discharge unit 120 disposed in the state shown in FIG. 9A as shown in FIG. 9B, all pure water discharged on the plate surface of the wafer W is accumulated and the discharge pressure of pure water By this, it does not stick out of the wafer W. In addition, when more pure water is discharged and accumulated on the plate surface of the wafer W, the area covered with pure water on the plate surface of the wafer W gradually increases, as shown in FIG. 9C, and the wafer ( Pure water is covered on the entire surface of W). At this time, the pure water applied on the wafer W does not fall out of the wafer W in a state in which a portion of the surface of the wafer W is covered by the surface tension, and the entire surface of the wafer W is made of pure water. After being covered, it is pushed by the pure water 99 which is additionally discharged from the liquid discharge unit 120 and falls in a form overflowing to the outside of the wafer W (Fig. 9E). Then, the pure water falling out of the wafer is collected by the recovery container and discharged.

Therefore, the entire surface of the wafer W is discharged at a low pressure, and the wetting state is maintained in a state covered with all the pure water 99 supplied to the plate surface. The sensor that detects whether or not it is seated 110 may fundamentally prevent damage by moisture, and since the wafer W is not deep-dipped, the handler can grip the edge of the wafer W at any time. Remains intact.

The wafer wetting device 100 according to an embodiment of the present invention configured as described above has advantages when applied to a loading unit or an unloading unit disclosed in a chemical mechanical polishing system according to Korean Patent Registration No. 10-1188579 Is maximized. That is, in order to perform a chemical mechanical polishing process in multiple stages on a plurality of polishing plates while the wafer carrier is moving, a loading unit for loading the wafer into the wafer carrier and an unloading unit for unloading the wafer after the chemical mechanical polishing process has ended. The wafer wetting device 100 configured as described above does not adopt a dipping method for immersing the wafer W in a liquid such as pure water, while the wafer is held in the wafer. Chemical mechanical polishing is performed in a multi-step chemical mechanical polishing process, as it can prevent (W) from being gripped immediately and prevent damage or failure of parts vulnerable to moisture such as sensors placed around the wafer by splashing pure water outside the wafer. Suitable for loading or unloading units of the system.

That is, the wafer wetting device 100 according to the present invention configured as described above discharges liquid at a low water pressure from the edge of the wafer to the top surface of the wafer W, so that the discharged pure water 99 of the wafer W By maintaining the wet state of the wafer W by staying on the surface and sequentially filling and covering the surface of the wafer W, while the wafer W is not dipping in the liquid, at the same time, a handler or the like can immediately grip the wafer While maintaining the standby state, and maintaining the wet state while controlling the pure water so that the pure water does not splash out to the surroundings, an advantage of preventing the surroundings from becoming dirty or the failure of peripheral parts is obtained.

The present invention has been exemplarily described through preferred embodiments, but the present invention is not limited to such specific embodiments, and various forms within the scope of the technical idea suggested in the present invention, specifically, the scope of the claims. Can be modified, changed, or improved.

W: Wafer 110: Holder
110s: support surface 120: liquid discharge unit
121: discharge port 99: pure water

Claims (9)

A holder supporting the wafer;
Dispensing and supplying pure water at a horizontal surface and an inclination angle of 10 degrees or less from the edge position of the wafer to the top surface of the wafer, but falling to the surface of the wafer without sticking out of the wafer and reaching the surface of the wafer A liquid discharge unit for discharging pure water under water pressure;
Containing, the pure water discharged by the liquid discharge unit does not stick out of the wafer, stays on the surface of the wafer, and is pushed by pure water that is discharged thereafter and falls on the surface of the wafer, so that the wafer surface In a form in which the area covered by pure water gradually increases, the pure water discharged over the entire surface of the wafer is spread and fills the surface of the wafer in order to maintain the wet state of the wafer, and the entire surface of the wafer is pure water. A wafer wetting device characterized in that it is further discharged after being covered by and is pushed by pure water supplied to the surface of the wafer to drop in the form overflowing out of the wafer.
delete According to claim 1,
The liquid discharge unit discharges pure water in a horizontal direction and supplies it to the plate surface of the wafer.
According to claim 1,
The holder is placed on the wafer so that the edge of the wafer is all exposed, characterized in that the wetting device of the wafer.
The method of claim 4,
The holder is placed on the wafer so that the edge of the wafer is all exposed, characterized in that the wetting device of the wafer.
According to claim 1,
The liquid is deionized water, characterized in that the wafer wetting device.
According to claim 1,
The liquid discharging unit is equipped with a plurality of discharge ports for discharging pure water in various directions.
The method of claim 1 or any one of claims 3 to 7,
The liquid discharge unit is a wafer wetting device, characterized in that the discharge port is located at a height within 30 mm from the top surface of the wafer.
The method of claim 1 or any one of claims 3 to 7,
The wafer wetting device is characterized in that it is used in any one or more of a loading unit for mounting a wafer in a chemical mechanical polishing system in which a chemical mechanical polishing process is performed on a plurality of polishing plates and an unloading unit for transferring the wafer to a cleaning process. Wafer wetting device.

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