KR20110060155A - Apparatus for high pressure cleaning and cleaning methods using the same - Google Patents

Abstract

PURPOSE: A high pressure dressing device and a dressing method using the same are provided to smoothly clean a polishing pad by easily controlling a distance between a polishing pad and a nozzle. CONSTITUTION: A high pressure dressing device comprises a nozzle unit(110) and a mobile robot(120). The nozzle unit faces a polishing pad of a top surface plate and a polishing pad(12,22) of a bottom surface plate and sprays high pressure water. The mobile robot is connected to the nozzle unit and selectively moves the nozzle unit between the top surface plate and the bottom surface plate. The distance between the nozzle unit and the polishing pad is controlled. The nozzle unit includes a spray cap with a spray hole.

Description

High pressure dressing apparatus and dressing method using the same {Apparatus for high pressure cleaning and cleaning methods using the same}

The present invention relates to a high pressure dressing apparatus and a dressing method using the same, and more particularly, a high pressure for smoothly cleaning the polishing pad by adjusting the height of the nozzle to easily adjust the distance between the polishing pad and the nozzle for polishing both sides of the wafer. A dressing apparatus and a dressing method using the same.

In general, in a silicon wafer manufacturing method, a polishing process is performed to improve the flatness of a silicon wafer (hereinafter referred to as a “wafer”), where the polishing process is typically performed by using a double-side polishing apparatus. Is polishing.

Referring to FIG. 1, the double-sided polishing apparatus 1 includes a lower plate 10 having a polishing pad 12 attached to an upper surface thereof, a polishing pad 22 attached to a lower surface thereof, and rotating the wafer W from above. The upper plate 20 and the carrier 50 is installed between the lower plate 10 and the upper plate 20 and the wafer (W) is mounted.

At this time, the polishing pads 12 and 22 used in the polishing process of the wafer W are polishing pads in which polymers are impregnated into felts (nonwoven fabrics).

More specifically, the inner gear 30 (internal gear) is provided on the outer circumference of the lower plate 10, and the sun gear 40 is installed at the center of the upper plate 20. The internal gear 30 and the sun gear 40 are respectively rotated in opposite directions as the lower plate 10 and the upper plate 20 rotate in opposite directions.

The carrier 50 has a substantially disc shape, and gears are formed at an outer circumference thereof to be engaged with the sun gear 40 and the internal gear 30. The carrier 50 is provided with a mounting hole (not shown) for mounting the wafer (W). Therefore, the wafer W is in close contact with the polishing pad 22 of the upper plate 20 and the polishing pad 12 of the lower plate 10 in a state where the wafer W is mounted on the carrier 50.

Meanwhile, a nozzle (not shown) for supplying a slurry (hereinafter referred to as a “polishing liquid”) in which abrasive particles and various additives are mixed is provided on the upper surface of the upper surface plate 20, and the upper surface plate 20 is provided. ) Is provided with an inlet (not shown) penetrated so that the polishing liquid supplied through the nozzle flows into the lower plate 10 side. That is, the polishing liquid is supplied through the inlet when the wafer W is polished. Accordingly, the wafer W in close contact with the polishing pads 12 and 22 is mechanically and chemically polished by a frictional force and a polishing liquid caused by relative movement.

That is, when the double-side polishing apparatus 1 is operated, the lower plate 10 and the upper plate 20 are rotated in opposite directions by a driving source (not shown), and the internal gear 30 and the sun gear 40 are also rotated. In conjunction with this, they are rotated in opposite directions. By the rotation of the internal gear 30 and the sun gear 40, the carrier 50 rotates and rotates to polish the wafer W by the polishing liquid and the high pressure working pressure.

As the polishing process proceeds as described above, as the number of polishing and polishing time of the wafer W increases, the surface of the polishing pads 12 and 22 becomes uneven to cause the flatness of the wafer W to deteriorate. do.

For example, polishing by-products (polishing liquid residue, polishing pad residue, silicon particles, etc.) generated during the polishing operation of the wafer W by the polishing liquid and the polishing pads 12 and 22 are the polishing pads 12 (22). Agglomeration and adhesion to the surface layer and the inner layer of) may cause a glazing phenomenon in which the reactive surface area of the polishing pads 12 and 22 is reduced. That is, the portion where the by-products are agglomerated and fixed by the glazing phenomenon is vitrified to cause the surface of the polishing pads 12 and 22 to be deformed, thereby causing the flatness of the wafer W to deteriorate.

Thus, the double-side polishing apparatus 1 performs dressings for cleaning the polishing pads 12 and 22 provided on the lower plate 20 and the upper plate 10.

The dressing method includes polishing pads 12 and 22 attached to each lower plate 10 and the upper plate 20 for 4 minutes every run after 40 minutes of polishing in both surfaces of the wafer W. A high pressure dressing device for spraying high pressure water with a high pressure is used to remove the abrasive by-products adhered to the polishing pads 12 and 22.

The high pressure dressing apparatus includes a spray nozzle for spraying high pressure water on the polishing pads 12 and 22 and a high pressure water supply unit for supplying high pressure water to the spray nozzle.

The high pressure dressing device is positioned between the upper plate 20 and the lower plate 10 from which the carrier 50 is removed, and the polishing pads 12 and 22 attached to each lower plate 10 and the upper plate 20. It is made to spray high pressure water of high pressure.

In this case, when the polishing pads 12 and 22 are cleaned using the spray nozzles, the polishing pads 12 may be disposed according to the distance between the spray nozzles and the upper plate 20 and the distance between the spray nozzles and the lower plate 10. Differences arise in the cleaning power for cleaning (22). That is, as shown in FIG. 2, the cleaning power decreases as the high-pressure water injected from the injection nozzle 2 moves away from the injection nozzle 2, and the cleaning power increases as it approaches the injection nozzle 2. Therefore, the distance between the injection nozzle 2 and the surface plate (lower surface plate and upper surface plate) should be adjusted to be the same.

In addition, since the number of polishing by-products of the wafer W and the amount of polishing by-products agglomerate and adhere to the polishing pads 12 and 22 are different, the distance between the jet nozzle and the surface plate is adjusted to adjust the polishing pad 12. Abrasive by-products attached to (22) should be removed.

However, when the distance between the injection nozzle and the surface plate is necessary, it is inconvenient to request the manufacturer of the double-side polishing apparatus 1 to adjust the lower limit of the upper surface plate 20.

In addition, there is an inconvenience that the distance between the spray nozzle and the surface plate should be adjusted to smoothly remove the polishing by-products by increasing or decreasing the cleaning power according to the degree of aggregation and sticking of the polishing by-products adhered to the polishing pads 12 and 22.

However, the adjustment of the distance position between the spray nozzle and the surface plate is predetermined and fixed at the time of set-up of the double-side polishing apparatus due to the time and cost problem, and the adjustment is almost impossible after that.

Therefore, if the cleaning is insufficient, the polishing by-products remain in the polishing pads 12 and 22 to worsen the flatness of the wafer W, and the life of the polishing pads 12 and 22 due to the glazing phenomenon. There is a problem that is shortened.

The present invention has been made to solve the above problems, a high-pressure dressing device and a dressing method using the same high pressure dressing that can spray the high pressure water by selectively adjusting the distance between the upper and lower polishing pad and the spray nozzle The purpose is to provide.

Another object of the present invention is to provide a high-pressure dressing device and a dressing method using the same, which smoothly removes the polishing by-products adhered to the polishing pad to improve the flatness of the wafer, as well as increase the use time of the polishing pad. have.

In order to achieve the above object, the high-pressure dressing apparatus of the present invention is a high-pressure dressing apparatus for cleaning the polishing pad attached to the upper and lower plates, respectively, attached to the upper surface of the lower surface and the polishing pad attached to the upper surface plate. A nozzle unit facing the polishing pad to spray high pressure water; And a moving robot connected to the nozzle unit to selectively move the nozzle unit between an upper plate and a lower plate, wherein the nozzle unit is configured to adjust a distance between each polishing pad attached to the upper plate and the lower plate. It is done.

Preferably, the nozzle unit has an injection cap having an injection hole, the injection cap is screwed to the upper tube and the lower tube of the nozzle unit, by rotating the injection cap and the distance between the upper plate and the injection cap, the lower plate and the injection cap You can adjust the distance between each.

Another nozzle unit according to the present invention further comprises an injection cap having a spray hole, the injection cap is coupled to slide in the upper tube and the lower tube of the nozzle portion, by moving the injection cap and the distance between the top plate and the injection cap, The distance between the lower plate and the injection cap can be adjusted.

High pressure dressing method for achieving the above object, the step of adjusting the interval between the top plate and the lower plate to the nozzle insertable interval; Moving the nozzle unit between an upper plate and a lower plate by a mobile robot; Adjusting the height of the nozzle unit so that the distance between the polishing pad and the nozzle unit attached to the upper and lower plates is closer or further away from each other; And cleaning each polishing pad by spraying high pressure water through the nozzle unit.

Preferably, the nozzle unit has an injection cap having an injection hole formed therein, the injection cap is coupled to be screwed or slid to the upper tube and the lower tube of the nozzle unit, by rotating or moving the injection cap between the top plate and the injection cap The distance and the distance between the lower plate and the injection cap can be adjusted respectively.

The high pressure dressing apparatus and the dressing method using the same according to the present invention have the following effects.

First, since the height of the nozzle can be selectively adjusted easily, it is possible to eliminate the inconvenience of adjusting the distance between the upper and lower plates and the nozzle by moving the upper plate.

Second, as the height of the nozzle portion is adjusted, the cleaning power for cleaning the polishing pad can be conveniently adjusted. That is, the smooth cleaning process may be performed in accordance with the increase in the number of polishing operations and the increase in polishing by-products as the polishing time passes.

Third, it is possible to easily remove the polishing by-products aggregated and adhered to the polishing pad to prevent vitrification of the polishing pad, thereby improving the service life of the polishing pad and improving the flatness of the wafer.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

Figure 3 is a side view schematically showing a high pressure dressing apparatus according to a preferred embodiment of the present invention, Figures 4 and 5 are views showing the operating state of the nozzle unit provided in the high pressure dressing device, respectively.

The high-pressure dressing apparatus 100 according to the present invention is a polishing pad 12 of the lower plate 10 and the upper plate 20 of the double-side polishing device 1 for polishing both sides of the wafer (W) shown in FIG. 22) for cleaning. Since the double-sided polishing apparatus 1 has been described above, a detailed description thereof will be omitted.

Hereinafter, the polishing pads 12 and 22 attached to the lower plate 10 and the upper plate 20 of the double-side polishing device 1 using the high pressure dressing apparatus 100 will be described. do.

3 to 5, the high pressure dressing apparatus 100 is provided to spray high pressure water onto each polishing pad 12 and 22 attached to the lower plate 10 and the upper plate 20 and has a height. It is provided with a nozzle unit 110 to be controlled, and a mobile robot 120 connected to the nozzle unit 110 to selectively move the nozzle unit 110 between the lower plate 10 and the upper plate 20.

The nozzle unit 110 is formed to face the polishing pad 12 attached to the upper surface of the lower plate 10 and the polishing pad 22 attached to the lower surface of the upper plate 20, respectively. That is, the nozzle unit 110 is made to spray high pressure water to the upper side and the lower side.

More specifically, the nozzle unit 110 is a transfer pipe 111 to move the high-pressure water, the lower pipe 112 and the upper pipe 114 formed by extending the lower end and the upper end of the transfer pipe 111, respectively, And, the injection pipe 115 is provided on the upper tube 114 and the lower tube 112, respectively.

The transfer pipe 111 is connected to a high pressure water supply unit (not shown) for supplying high pressure water. Accordingly, the high pressure water transferred to the transfer pipe 111 is injected through the lower pipe 112 and the upper pipe 114.

On the other hand, the injection cap installed in the lower pipe 112 is called the lower cap 116, the injection cap installed in the upper pipe 114 is called the upper cap 118, the lower cap 116 and the upper cap 118 Collectively referred to as the injection cap (115). The lower cap 116 and the upper cap 118 is formed with a spray hole 117 is injected with high pressure water.

The injection cap 115 is screwed to the lower tube 112 and the upper tube 114 is made to adjust the distance to the polishing pad 12, 22 as it is rotated. That is, threads 112 'and 114' are formed in the lower tube 112 and the upper tube 114, respectively, and the lower cap 116 and the upper cap 118 have the lower tube 112 and the upper tube ( Threads 116 ′ and 118 ′ are formed that are screwed into 114. Accordingly, the lower cap 116 and the upper cap 118 are moved in a direction away from or close to the polishing pads 12 and 22 according to the rotation direction, respectively. For example, when the upper cap 118 is rotated counterclockwise, it is closer to the polishing pad 22 of the upper plate 20, and when the upper cap 118 is rotated clockwise, the polishing pad 22 of the upper plate 20 Away.

On the other hand, in the present specification, the nozzle unit 110 is made of a screw type is shown and described that the distance to the polishing pad 12, 22 is adjusted, but is not limited to this, as shown in Figure 6, sliding type Consisting of the polishing pads 12, 22 can be adjusted to the distance.

Referring to FIG. 6, the nozzle unit 210 includes a transfer pipe 211 through which high pressure water is moved, a lower tube 212 formed by extending end portions of the transfer pipe 211 toward the lower side and the upper side, and an upper tube ( 214 and an injection cap 215 consisting of a lower cap 216 installed to slide in the lower tube 212 and an upper cap 218 installed to slide in the upper tube 214.

Here, guide grooves 212 'and 214' are formed in the lower tube 212 and the upper tube 214, respectively, and the guide grooves 212 'are formed in the lower cap 216 and the upper cap 218, respectively. Protrusions 216 'and 218' inserted into 214 'are formed. That is, the lower cap 216 and the upper cap 218 are made so as not to be separated from the lower tube 212 and the upper tube 214 and are slid in the longitudinal direction of the guide grooves 212 ′ and 214 ′ so that the polishing pad ( 12) (22) is moved in the direction away from or close to.

On the other hand, the sliding type injection cap 215 is preferably made to have a plurality of injection caps different in length from the upper surface formed with the injection hole to the lower surface formed with the projections (216 ', 218'). This is to adjust the cleaning power according to the length of the injection cap 215 sliding during injection, the longer the length of the injection cap 215 is closer to the surface plate, the shorter the length of the injection cap 215 and the surface plate The distance is far away. Therefore, the injection cap 215 may be replaced according to circumstances to implement a desired cleaning force.

3 to 5, the mobile robot 120 includes a robot arm 122 for moving the nozzle unit 110.

More specifically, the mobile robot 120 moves the nozzle unit 110 located at the outside of the lower plate 10 and the upper plate 20 between the lower plate 10 and the upper plate 20. At this time, when the nozzle unit 110 is moved between the lower plate 10 and the upper plate 20, the lower tube 112 and the upper tube 114, respectively, the polishing pad 12 and the lower plate 10 The polishing pad 22 of the upper surface plate 20 is in a state spaced apart from each other.

In addition, the mobile robot 120 reciprocates the nozzle unit 110 located between the lower plate 10 and the upper plate 20 from the edge of the lower plate 10 and the upper plate 20 to the center. That is, the nozzle unit 110 is reciprocated by the robot arm 122.

The mobile robot 120 is provided with a conventional driving means such as a servo motor, a hydraulic motor, which is moved according to the rotational motion of the belt, pneumatic and hydraulic cylinder, cam or gear, and is connected to the robot arm 122 to the robot The arm 122 is driven. At this time, the robot arm 122 is made to clean the polishing pads 12 and 22 by moving in a straight and curved trajectory in the edge side direction of the lower plate 10 and the upper plate 20. This drive is controlled by a computer program. Since the mobile robot 120 is moved to a designated position by using the computer program, and the technique of reciprocating the robot arm 122 is already known, a detailed description thereof will be omitted.

On the other hand, unexplained reference numeral 'V' is a conventional valve for adjusting the flow rate, pressure, etc. of the fluid.

Next, a method of cleaning the polishing pads 12 and 22 using the high pressure dressing apparatus 100 as described above will be described with reference to FIGS. 3 to 5.

First, the wafer W is polished a predetermined number of times or a predetermined time using the wafer double-side polishing apparatus 1 shown in FIG. 1, and then the wafer W is mounted to clean the polishing pads 12 and 22. Remove the carrier 50. In this process, the upper surface plate 10 of the double-sided polishing apparatus 1 is moved upward to maintain the gap in which the nozzle unit 110 can be moved between the lower surface plate 10 and the upper surface plate 20. The moving distance of the upper plate 20 is set up in advance.

Subsequently, the nozzle unit 110 is moved between the lower plate 10 and the upper plate 20 by the mobile robot 120. At this time, the injection cap 115 of the nozzle unit 110 is spaced apart at regular intervals so as not to contact the polishing pads 12 and 22 of the lower plate 10 and the upper plate 20.

Subsequently, the injection cap 115 is moved in a direction approaching or away from the polishing pads 12 and 22. Here, since the high pressure water injected from the injection cap 115 occurs in the cleaning power according to the injection distance, the injection cap 115 is selectively moved according to the cleaning power for cleaning the polishing pads 12 and 22. You have to. For example, at the beginning of the polishing process, since there are relatively fewer polishing by-products than the latter part of the polishing process, the height of the injection cap 115 is decreased to decrease the cleaning power, and then the polishing pads 12 and 22 are cleaned, and the polishing by-products are increased. In the latter half of vitrification, it is preferable to increase the height of the injection cap 115 to narrow the distance to the polishing pads 12 and 22 and to increase the cleaning power to clean the glass nitriding.

Meanwhile, the distance between the lower cap 116 installed on the lower tube 112 and the polishing pad 12 of the lower plate 10 and the polishing pad of the upper cap 118 and the upper plate 20 installed on the upper tube 114 Since the distance to the 22 may be different from each other, the installation heights of the lower cap 116 and the upper cap 118 should be adjusted so that the distances from the polishing pads 12 and 22 are the same.

The installation height of the injection cap 115 is adjusted by rotation or sliding. That is, the installation height is adjusted by rotating the screw type injection cap 115 shown in FIGS. 4 and 5, or the installation height is adjusted by moving the injection type cap 215 of the sliding type shown in FIG. 6.

When the installation height of the injection caps 115 and 215 is adjusted, the high pressure water is sprayed onto the polishing pads 12 and 22 to be cleaned. At this time, the upper plate 20 and the lower plate 10 is rotated, the nozzle unit 110 is reciprocated from the edge of the lower plate 10 and the upper plate 20 to the center by the mobile robot 120 The polishing pads 12 and 22 are made to be cleaned.

The dressing method as described above may be programmed to stop the double-side polishing operation of the wafer and to clean the polishing pad after a predetermined time reaches the set number of times, or after a predetermined time.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto and is intended by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalents of the claims to be described.

The present invention will be described in detail with reference to the following drawings, but these drawings illustrate preferred embodiments of the present invention, and the technical concept of the present invention is not limited to the drawings and should not be interpreted.

1 is a perspective view schematically showing a double-side polishing apparatus for polishing both sides of a wafer.

2 is a view showing a difference in cleaning power according to the injection distance of the nozzle.

Figure 3 is a side view showing a high pressure dressing device according to a preferred embodiment of the present invention.

4 and 5 are cross-sectional views showing the operating state of the nozzle unit provided in the high pressure dressing device, respectively.

Figure 6 is a cross-sectional view showing another nozzle portion provided in the high-pressure dressing device according to a preferred embodiment of the present invention.

Claims (5)

In the high pressure dressing apparatus for cleaning the polishing pad attached to the upper and lower plates respectively, A nozzle unit provided to spray high pressure water so as to face a polishing pad attached to a lower surface of the upper plate and a polishing pad attached to an upper surface of the lower plate; And And a mobile robot connected to the nozzle unit to selectively move the nozzle unit between an upper plate and a lower plate. The nozzle unit is a high-pressure dressing device, characterized in that the distance between the upper and lower polishing pads attached to the lower plate is made to be adjusted. The method of claim 1, The nozzle unit has an injection cap formed with a spray hole, The injection cap is screwed to the upper tube and the lower tube of the nozzle portion, the high-pressure dressing device, characterized in that by rotating the injection cap to adjust the distance between the upper plate and the injection cap, and the distance between the lower plate and the injection cap, respectively . The method of claim 1, The nozzle unit further includes an injection cap in which the injection hole is formed, The injection cap is coupled so as to slide in the upper tube and the lower tube of the nozzle unit, by moving the injection cap to adjust the distance between the top plate and the injection cap, and the distance between the lower plate and the injection cap, respectively, characterized in that the high pressure dressing Device. Adjusting an interval between the upper and lower plates to an interval at which the nozzle unit can be inserted; Moving the nozzle unit between an upper plate and a lower plate by a mobile robot; Adjusting the height of the nozzle unit so that the distance between the polishing pad and the nozzle unit attached to the upper and lower plates is closer or further away from each other; And And spraying the high pressure water through the nozzle unit to clean each polishing pad. 5. The method of claim 4, The nozzle unit has an injection cap formed with a spray hole, The injection cap is screwed or slidably coupled to the upper tube and the lower tube of the nozzle unit, by rotating or moving the injection cap to adjust the distance between the upper plate and the injection cap, and the distance between the lower plate and the injection cap, respectively High pressure dressing method, characterized in that.

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