KR100879761B1 - Chemical mechanical polishing apparatus and polishing pad dressing method using the same - Google Patents

Abstract

A chemical mechanical polishing apparatus and a polishing pad dressing method using the same are disclosed. Chemical mechanical polishing apparatus according to the present invention is a turntable rotatably installed; A soft polishing pad attached to the turn table for polishing the surface of the wafer and in contact with the wafer; A polishing head rotatably disposed above the polishing pad to fix the wafer at a lower portion thereof, and to reciprocate in a direction approaching and spaced apart from the polishing pad to contact and press the wafer to the polishing pad; And a dresser polishing layer rotatably disposed above the polishing pad and attached to a lower portion of the dresser polishing layer for controlling the surface characteristics of the polishing pad, and reciprocating in a direction approaching and spaced apart from the polishing pad, And a dresser for contacting and pressing the layer to the polishing pad, wherein the dresser polishing layer is a layer in which a plurality of diamond particles are fixed to the edge of the dresser bottom in a ring type.

Description

Chemical mechanical polishing apparatus and polishing pad dressing method using same {Apparatus for chemical mechanical polishing and method of dressing using the same}

Fig. 1 shows the shape of each polishing pad immediately after replacement and after the dummy wafer polishing, in the case where the dummy wafer polishing is performed for 40 minutes by applying the conventional method immediately after the polishing pad replacement.

2 is a schematic configuration diagram of a chemical mechanical polishing apparatus according to the present invention.

3 is a front view showing in detail the dresser and the polishing pad of the apparatus of FIG.

4 illustrates a polishing pad and a wafer shape according to the diamond shape and size of the dresser polishing layer provided in the apparatus of FIG. 2.

FIG. 5 shows the polishing pad and wafer shape according to the dresser and polishing pad rotation speed in the apparatus of FIG. 2.

Figure 6 shows the polishing pad shape change with glazing occurrence and dressing.

Figure 7 shows the wafer polishing rate change with glazing occurrence and dressing.

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

10 ... Chemical mechanical polishing device 100 ... Turn table

200 ... polishing pad 300 ... polishing head

400 ... dresser 410 ... dresser polishing layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical mechanical polishing (CMP) apparatus, and more particularly, to a CMP apparatus for wafer manufacture.

In general, in the process of manufacturing a bare silicon wafer for semiconductor device manufacturing, a slicing process of cutting cylindrical silicon (ingot) into individual wafers is performed. In slicing, diamond blades are used or piano wires called wire saws are used. At this time, since irregularities exist on the cut wafer surface, the planarization process must be performed.

In addition, the semiconductor device manufacturing process includes a deposition process for forming a thin film layer on the wafer and an etching process for forming a fine circuit pattern on the thin film layer. These processes are repeated until the required circuit pattern is formed on the wafer, and there are many steps on the surface of the wafer. In addition, as the semiconductor devices are highly integrated, the line width of the circuit is reduced, and more wirings are stacked on one chip, thereby increasing the step height depending on the position inside the chip. Steps make it difficult to evenly apply the metallization layer in subsequent processes, so a planarization process is required to remove them.

As described above, in planarizing the surface of the bare silicon wafer and the wafer on which the pattern is formed, a method using a CMP apparatus capable of obtaining excellent flatness in not only a narrow region but also a wide region is mainly used.

Generally, a CMP apparatus consists of a polishing head, a turn table, and a polishing pad supported by the turn table. The polishing head fixes the wafer so that the polishing surface of the wafer faces the polishing pad and presses onto the polishing pad. During polishing, an abrasive slurry, such as a colloidal silica slurry, is provided between the polishing pad and the wafer on the polishing pad, and chemical components in the polishing slurry react with the wafer surface to form a reaction layer. Create This reaction layer is physically removed by the polishing head and the polishing pad rotating each other about their respective drive shafts, thereby rubbing the wafer polishing surface attached on the polishing head and the polishing pad in close contact with each other.

However, the surface of the polishing pad is adhered to the wafer reactant, slurry particles, foreign matter, etc. after vitrification by high pressure and temperature (so-called glazing), and the relative movement distance between the polishing pad and the wafer depending on the position of the polishing pad. Uneven surface deformation occurs due to the difference, which degrades the polishing rate, flatness, surface roughness, and the like in the wafer polishing characteristics. Therefore, polishing pad dressing that maintains the polishing rate of the wafer through polishing pad glazing removal and polishing pad surface shape control and improves flatness and surface roughness is essential.

In particular, the polishing pad used in the CMP device for wafer manufacturing is a soft polishing pad, in which a polyester felt structure is impregnated with polyurethane. Due to the nature of the manufacturing process, the polishing pad thickness, Differences occur in various properties, such as compression rate and hardness, which may adversely affect wafer polishing property control. Therefore, in order to control non-uniform polishing pad surface characteristics at the beginning of using the polishing pad, the polishing pad surface is compressed to a uniform shape by a dummy wafer, ceramic plate, etc. according to the type of polishing process (so-called seasoning). The wafers for production are being polished. This also applies to prolonged downtime or sudden variations in wafer polishing characteristics during use of the polishing pad. In addition, each time polishing is completed, high-pressure deionized water (DIW) injection is performed to remove wafer reactants, slurry particles, and foreign substances remaining on the surface of the polishing pad.

Conventionally, the contact pressure of the polishing surface in the polishing pad surface characteristics control by the dummy wafer or the ceramic plate is 260 gf / cm 2, the rotation speed of the wafer and the polishing pad is 120 RPM, the polishing slurry flow rate is 0.7 L / min, and the polishing time is 40 minutes (Pad: SUBA 800M2, CMP equipment: POLI-500). Fig. 1 shows the shape of each polishing pad immediately after replacing the polishing pad and after performing the dummy wafer polishing when the dummy wafer polishing is performed for 40 minutes by applying such a conventional method. In FIG. 1, the x axis represents the length from the polishing pad center to the polishing pad outer peripheral direction and the y axis represents the polishing pad profile.

As can be seen from Fig. 1, in the case of applying the conventional method, the polishing pad profile is not significantly different immediately after replacing the polishing pad and after performing the dummy wafer polishing for 40 minutes. That is, the conventional method for controlling the polishing pad shape according to the polishing of the dummy wafer (or ceramic plate) has a small difference in the shape of the polishing pad before and after the work, so that the polishing pad shape control effect is small.

In addition, the high pressure DIW spraying performed immediately after each polishing delays the polishing pad glazing occurrence time and reduces the amount of glazing generation. However, it is not possible to prevent the deterioration of wafer polishing characteristics due to the glazing occurrence because the glazing generated is not removed. .

Polishing pads used in CMP devices for semiconductor device manufacturing are hard IC-based polishing pads, which perform a dressing operation to cut the polishing pad surface with a dresser to return it to its original state when the surface of the polishing pad is deformed or blocked by CMP. do. However, when a dresser for manufacturing a semiconductor is used to dress a soft polishing pad used in a wafer polishing process, the polishing pad may be over-weared, resulting in damage to the fiber structure on the surface and deterioration of the function of the polishing pad. Therefore, dressing of the soft polishing pad requires a dresser which has less wear and less damages the polishing pad surface than the dresser applied to the conventional IC series polishing pad.

It is an object of the present invention to provide a CMP apparatus capable of performing appropriate and effective dressing operations in place of dummy wafer (or ceramic plate) polishing and DIW spraying on soft polishing pads.

It is another object of the present invention to provide a method for dressing a soft polishing pad using such a CMP apparatus.

In order to achieve the above object, the CMP apparatus according to the present invention comprises a turn table rotatably installed; A soft polishing pad attached to the turn table for polishing the surface of the wafer and in contact with the wafer; Rotatably disposed above the polishing pad to fix the wafer at a lower portion thereof, and to reciprocate in a direction approaching and spaced apart from the polishing pad to contact and press the wafer to the polishing pad. Polishing head; And a dresser polishing layer rotatably disposed above the polishing pad and attached to a lower portion of the dresser polishing layer for controlling surface characteristics of the polishing pad, and reciprocating in a direction approaching and spaced apart from the polishing pad. And a dresser for contacting and pressing the dresser polishing layer to the polishing pad, wherein the dresser polishing layer is a layer in which a plurality of diamond particles are fixed to an edge of the bottom of the dresser in a ring type.

Here, the diamond particles are MBG 680 or MBE 925 and the size is Mesh 80 ~ 140, or the shape is MBG 660 and the size is preferably Mesh 170 ~ 230.

In order to achieve the above another object, the dressing method according to the present invention is a soft polishing pad dressing method using a CMP apparatus according to the present invention, comprising: rotating the turn table to rotate the polishing pad; And rotating the dresser by contacting and pressing the dresser against the polishing pad.

At this time, the pressure applied by the dresser to the polishing pad is 20 to 60 gf / cm 2, the dressing time is 3 to 15 minutes, the rotational speed ratio of the dresser to the rotational speed of the polishing pad is 0.25 to 0.75, and the polishing Pad rotational speed is preferably 90 ~ 150 RPM. The method may further include supplying deionized water to the polishing pad before and after performing the dressing. The polishing slurry or deionized water is supplied during the dressing, and the flow rate of the polishing slurry or deionized water at this time is preferably 1 to 2 L / min.

As such, the present invention provides a CMP apparatus having a dresser suitable for the soft polishing pad dressing of the CMP process for wafer fabrication, and derives the diamond size and shape of the dresser polishing layer provided in the dresser, Prevents wear and controls polishing pad surface shape and roughness, ultimately improving wafer polishing properties. The present invention also derives dressing operating conditions (dressing pressure, time, rotational speed) suitable for improving wafer polishing properties. When glazing occurs in the polishing pad during the wafer polishing process, the polishing process may be improved through a method of improving polishing pads and wafer polishing characteristics through dressing using the derived dressing operating conditions.

Hereinafter, the present invention will be described in detail by explaining a CMP apparatus and a dressing method according to a preferred embodiment of the present invention with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only this embodiment is to complete the disclosure of the present invention, those skilled in the art to which the present invention belongs It is provided to fully inform the scope of the invention, and the invention is defined only by the scope of the claims. Like numbers refer to like elements throughout the drawings and the specification.

2 is a schematic diagram of a CMP apparatus 10 according to the present invention.

Referring to FIG. 2, the CMP apparatus 10 according to the present invention includes a turn table 100, a polishing pad 200, a polishing head 300, a dresser 400, a polishing slurry supply unit 600, and the like.

The turn table 100 is rotatably installed and has its own drive shaft 101 at the bottom, and although not shown in the drawing, a rotation means for rotating the drive shaft 101 is mounted at the bottom of the drive shaft 101, for example, a motor. And rotation speed control is possible.

The polishing pad 200 has a circular shape and is attached onto the turn table 100 by an adhesive. The upper surface 210, which is the polishing surface of the polishing pad 200, mechanically polishes the wafer W by direct contact with the wafer W. The polishing pad 200 here is a soft polishing pad.

Exemplary soft polishing pads may be impregnated with polyester in a polyester felt tissue. It may also be a felt sheet of fibers containing micro porous elastomer.

The polishing head 300 is disposed on the polishing pad 200 so that the surface of the wafer W to be polished faces the polishing pad upper surface 210 so that the wafer W is fixed to the lower surface thereof and polished. The wafer W is pressed on the pad 200. More specifically, the method of fixing the wafer W to the polishing head 300 generally uses wax, which is a kind of adhesive, or a backing film and a wafer attached to the polishing head 300. The surface tension by water is used between (W). The driving shaft 301 is coupled to the upper portion of the polishing head 300 and the driving shaft 301 is connected to a motor (not shown) to rotate the polishing head 300 and control the rotation speed. In addition, the drive shaft 301 is also connected to a reciprocating means, for example, a linear motor (not shown) to reciprocate the polishing head 300 in a direction away from the direction approaching the polishing pad 200.

Figure 3 is a front view showing in more detail the dresser 400 and the polishing pad 200 portion of the CMP apparatus 10 according to the present invention.

2 and 3 together, the dresser 400 is rotatably disposed above the polishing pad 200, and the driving shaft 401 is coupled to the upper portion of the dresser 400, and the driving shaft 401 is connected to a motor (not shown). Is connected, the dresser 400 rotates and the rotation speed can be controlled. In addition, the drive shaft 401 is also connected to a reciprocating means, for example, a linear motor (not shown) to reciprocate the dresser 400 in a direction away from a direction approaching the polishing pad 200. The overall role of this role is illustrated and referred to herein as the rotary part 500.

A dresser polishing layer 410 corresponding to the polishing pad upper surface 210 is attached below the dresser 400. The dresser 400 contacts and presses the dresser polishing layer 410 to the polishing pad 200. Here, the dresser polishing layer 410 is a layer in which a plurality of diamond particles are fixed to the edge of the bottom of the dresser 400 in a ring type.

In the present invention, the polishing pad according to the size, shape and dressing pressure (downward force applied to the polishing pad 200 by the dresser 400) of the diamond particles of the dresser polishing layer 410, the dressing time, the polishing slurry flow rate, etc. The polishing amount of the upper surface 210 may be variously implemented, and the shape of the polishing pad upper surface 210 may be variously implemented according to the rotational speeds of the dresser 400 and the polishing pad 200. The dressing may also remove the glazing formed on the polishing pad upper surface 210 during polishing.

In order to improve the wafer polishing characteristics by controlling the surface shape and the roughness of the polishing pad without causing excessive wear of the polishing pad, as in the experimental example described later, when the diamond shape of the dresser polishing layer 410 is MBG 680 or MBE 925 If the diamond size is Mesh 80 ~ 140 and the diamond shape is MBG 660, the diamond size should be Mesh 170 ~ 230.

(* Diamond shape: 7 types of MBG 300, 600, 610, 620, 640, 660, 680, etc.The larger the number, the rounder the shape, and the smaller the number, the rougher shape. MBE 925 Has an intermediate shape between MBG 660 and 680. MBG stands for Metal Bonding for Grind, which is a diamond for precision grinding made by DI, and MBE stands for Metal Bonding for Electroplating. Diamond.)

(* Diamond size, expressed in mesh units. Mesh represents the mesh size, which represents the number of meshes within 1 inch (25.4mm). The larger the mesh, the smaller the mesh size and the particles that can enter the mesh. Smaller.)

During dressing of the polishing pad 200 using the dresser 400, the CMP apparatus 10 according to the invention may further be provided with a device for supplying a rinsing liquid such as DIW.

Hereinafter, the operation of the CMP apparatus 10 according to the present invention having the above-described configuration will be described.

The wafer W is fixed to the polishing head 300 and transferred onto the polishing pad 200 to start the polishing process. The polishing slurry supply unit 600 supplies a liquid polishing slurry 610 onto the polishing pad 200. The polishing slurry supplied over the polishing pad 200 is spread along the polishing pad 200 by the rotation of the turntable 100, and is supplied between the wafer W and the polishing pad 200.

In this state, the polishing head 300 is disposed on one side from the center of the polishing pad 200 and rotates about its drive shaft 301 with the wafer W fixed. In addition, the polishing pad 200 is rotated together about the drive shaft 101 of the turn table 100 by the rotation of the turn table 100. Therefore, in a state where the wafer W and the polishing pad 200 are in contact with each other, the wafer W is rubbed against the polishing pad upper surface 210 by the relative movement of the polishing head 300 and the polishing pad 200. Polishing of W) proceeds.

As the polishing proceeds, the polishing pad upper surface 210 may be glazed due to high pressure and temperature of the wafer reactant, slurry particles, and foreign matter, and the polishing pad 200 and the wafer ( Uneven surface deformation occurs due to the difference in relative movement distance between W). In the present invention, the dressing process using the dresser 400 may be performed after or simultaneously with polishing to maintain the polishing rate of the wafer through polishing pad glazing and shape control, and improve flatness and surface roughness. In addition, after controlling the surface of the polishing pad 200 to a uniform shape by first performing a dressing process using a dresser 400 and seasoning to control non-uniform polishing pad surface characteristics at the beginning of using the polishing pad 200. Polishing may also be performed on the production wafer.

Operation of the dresser 400 in the CMP apparatus 10 soon becomes the polishing pad dressing method according to the present invention. The dressing process is started by the dresser 400 pressing-contacting the dresser polishing layer 410 to the polishing pad 200. Before performing the dressing, DIW may be supplied onto the polishing pad 200 and rinsed. The polishing slurry supply 600 may supply a liquid polishing slurry 610 over the polishing pad 200 during dressing. Alternatively, DIW can be fed during dressing using a separate device as mentioned above. The dresser 400 is disposed on one side from the center of the polishing pad 200 and rotates about its drive shaft 401. In addition, the polishing pad 200 is rotated together about the drive shaft 101 of the turn table 100 by the rotation of the turn table 100. Therefore, in the state where the dresser polishing layer 410 and the polishing pad 200 are in contact with each other, the dresser polishing layer 410 is rubbed by the relative movement of the dresser 400 and the polishing pad 200, thereby causing the surface of the polishing pad 200 to be polished. Dressing.

When the diamond shape of the dresser polishing layer 410 is MBG 680 or MBE 925 and the diamond size is Mesh 80 to 140, and the diamond shape is MBG 660 and the diamond size is Mesh 170 to 230, the polishing pad and wafer polishing characteristics are improved. Suitable dressing pressure is 20 ~ 60gf / ㎠, dressing time is 3 ~ 15 minutes, the rotational speed ratio of the dresser 400 to the rotational speed of the polishing pad 200 is 0.25 ~ 0.75, the rotational speed of the polishing pad 200 is It is preferable that it is 90-150 RPM, and the flow volume of DIW or polishing slurry is 1-2 L / min. After the dressing is performed, rinsing may be performed by feeding DIW onto the polishing pad 200.

Experimental Example 1

Polishing characteristics according to the diamond shape and size of the dresser polishing layer 410 were verified.

As shown in Table 1, four types of dresser polishing layers 410 used for the verification were indicated by # 1- # 4. In the dressing experiment conditions using the dresser polishing layers 410, the dressing pressure was 60 gf / Cm 2, dresser and polishing pad rotation speeds were 60 RPM and 120 RPM, dressing time was 5 minutes, and DIW flow rate was 1.4 L / min.

Factors for evaluating the polishing characteristics include the roll-off value and the flatness of the wafer. In general, when the polishing is performed through the rotational movement, the polishing object tends to be polished more than the center portion. Accordingly, the polished wafer has a convex shape of the wafer because the thickness of the edge is smaller than the thickness of the center portion, which is called a rolloff, and is a numerical value for measuring the convexity of the wafer. The convex shape causes the rolloff value to be positive. Flatness is a standardized value such as Total Thickness Variation (TTV) representing the difference between the maximum and minimum thicknesses of the wafer, and Local Thickness Variation (LTV) representing the local thickness difference, and SBIR, which is standardized in the SEMI MI. (site backside ideal range).

In this experiment, the polishing pad profile for each dresser polishing layer, roll off before application and after 5 minutes dressing, and SBIR were measured. The results are shown in Table 1.

As a result of the verification, as shown in Table 1 under the conditions of MBE 925, mesh 100 (# 1), MBG 660, mesh 170 (# 4), polishing pads did not occur and showed excellent wafer flatness. No wafer scratches occurred after polishing under all conditions.

4 shows the polishing pad and wafer shape according to the diamond shape and size of the dresser polishing layer.

In FIG. 4, the polishing pad profile and the wafer shape are flat when the MBE 925 and the mesh 100 (# 1) conditions are applied as compared to the polishing pad profile and the wafer shape before the dressing application, and the MBE 925 and the mesh 60 (# 2) conditions are applied. The polishing pad profile is much flatter and the wafer shape can be seen to be concave.

Experimental Example 2

The polishing characteristics of the dresser and the polishing pad (turn table) were verified.

As shown in Table 2, the rotation speeds of the dresser and the polishing pad used for the verification were four pairs indicated by # 5- # 8, and the dresser polishing layer 410 was evaluated as MBE 925, mesh which was evaluated as excellent in Experimental Example 1. 100 (# 1) was used, the dressing pressure was 60 gf / cm 2, the dressing time was 10 minutes, and the DIW flow rate was 1.4 L / min.

In this experiment, the polishing pad profiles, roll-offs before and after 10-minute dressing, and SBIR were measured for each rotational speed pair, and the results are shown in Table 2.

As a result of the verification, when the dresser's rotational speed ratio to the rotational speed of the polishing pad was 0.5 (# 6), wafer flatness was the best.

5 shows the polishing pad and wafer shape according to the dresser and polishing pad rotation speed.

In FIG. 5, the polishing pad profile and the wafer shape are flat when the dresser rotation speed 60 RPM and the polishing pad rotation speed 120 RPM (# 6) conditions are applied as compared to the polishing pad profile and the wafer shape before the dressing application, and the dresser rotation speed 120 RPM, Polishing Pad Rotation The polishing pad profile is much concave and wafer shape is convex when applying 60 RPM (# 7) conditions.

As a result of all the experimental results, when the diamond shape and size specified in Experimental Example 1 were applied, the dressing pressure suitable for improving the polishing pad and wafer polishing characteristics was 20 to 60 gf / cm 2, the dressing time was 3 to 15 minutes, It was found that the ratio of the rotational speed of the dresser to the rotational speed was 0.25-0.75, the rotational speed of the polishing pad was 90-150 RPM, and the flow rate of the polishing slurry or DIW was 1-2 L / min. In addition, when the dresser rotational speed ratio to the rotational speed of the polishing pad was 0.5, the wafer flatness was found to be the best.

Experimental Example 3

If glazing occurs on the surface of the polishing pad during polishing, polishing is performed by applying a dressing method applying diamond shape, size, and dressing operating conditions excellent in wafer flatness without the occurrence of polishing pad excessive wear derived in Experimental Examples 1 and 2 above. By removing the glazing of the pad surface, the polishing pad shape and the polishing rate, surface roughness, and scratch incidence rate of the wafer can be restored before the glazing occurrence.

6 shows the polishing pad shape change with glazing occurrence and dressing.

Referring to FIG. 6, the polishing pad is relatively flat immediately after the polishing pad is replaced. However, when the wafer is polished for 3 hours, glazing occurs and the polishing pad flatness is deteriorated. When the dressing method according to the present invention is applied to the polishing pad in which the glazing is generated, it can be seen that the shape of the polishing pad is recovered before the glazing occurs.

As described above, when dressing is performed using the CMP apparatus according to the present invention, the polishing pad shape is changed to be more uniform and flat than when the dressing is not performed as before, or when polishing is performed with a dummy wafer or a ceramic plate. Therefore, after grinding, the wafer shape becomes more concave to achieve flatness improvement due to reduced wafer edge rolloff. In other words, by performing diamond dressing on the soft polishing pad, wafer flatness quality can be improved through polishing pad shape control.

Figure 7 shows the wafer polishing rate change with glazing occurrence and dressing.

Referring to FIG. 7, the polishing rate is 0.9 μm / min immediately after the polishing pad is replaced, but the polishing rate is rapidly decreased to 0.25 μm / min after performing wafer polishing for 3 hours. This is because of the occurrence of glazing as seen in FIG. 6, and when the dressing method according to the present invention is applied to the polishing pad in which the glazing is generated, it can be seen that the polishing rate is restored to 0.95 μm / min or more.

In the above, the present invention has been described in detail with reference to preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications are possible by those skilled in the art within the technical idea of the present invention. Is obvious. For example, in addition to the soft polishing pad used for the polishing process for wafer fabrication, the polishing pad and wafer polishing characteristics are applied to the same polyurethane-based MH polishing pad as the IC polishing pad for semiconductor CMP by applying the dressing pressure, time, and rotation speed specified in the present invention. Can improve.

Embodiments of the invention have been considered in all respects as illustrative and not restrictive, including the scope of the invention as indicated by the appended claims rather than the detailed description therein, the equivalents of the claims and all modifications within the means. I want to.

The CMP apparatus and dressing method according to the invention are particularly optimized to prevent over-wear of the soft polishing pad.

According to the present invention, when glazing occurs on the surface of the polishing pad, the diamond dressing is performed, unlike the existing high-pressure DIW injection, thereby eliminating the glazing, and thus the polishing pad shape, wafer roughness, surface roughness, and scratch incidence rate are reduced. Recover before glazing occurs. Therefore, it is possible to reduce the expendable consumable cost, increase the wafer polishing rate, and reduce the scratch defect rate according to the life of the polishing pad. In addition, it is possible to reduce the deterioration of wafer polishing characteristics due to the non-uniform polishing pad surface in the polishing step, which is a wafer final processing process.

In addition, the polishing pad seasoning effect can be obtained by applying the conditions of the dressing method specified in the present invention for seasoning at the beginning of use of the polishing pad. This has the advantage that the desired polishing pad surface characteristics can be controlled in a short time than seasoning using a dummy wafer or ceramic plate.

Claims (6)

A turn table rotatably installed; A soft polishing pad attached to the turn table for polishing the surface of the wafer and in contact with the wafer; Rotatably disposed above the polishing pad to fix the wafer at a lower portion thereof, and to reciprocate in a direction approaching and spaced apart from the polishing pad to contact and press the wafer to the polishing pad. Polishing head; And It is rotatably disposed above the polishing pad and attached to the lower portion of the dresser polishing layer for controlling the surface characteristics of the polishing pad, and reciprocating in a direction approaching and spaced apart from the polishing pad, A dresser for contacting and pressing the dresser polishing layer to the polishing pad, The dresser polishing layer is a layer in which a plurality of diamond particles are fixed to the edge of the bottom of the dresser in a ring type, and the diamond particles are MBG 680 or MBE 925 and have a mesh size of 80 to 140 or a MBG 660 and size. Chemical mechanical polishing apparatus characterized in that the mesh 170 ~ 230. delete A soft polishing pad dressing method using the chemical mechanical polishing apparatus of claim 1, Rotating the polishing pad by rotating the turn table; And Rotating the dresser by contacting and pressing the dresser against the polishing pad, The pressure applied by the dresser to the polishing pad is 20 to 60 gf / cm 2, the dressing time is 3 to 15 minutes, the rotational speed ratio of the dresser to the rotational speed of the polishing pad is 0.25 to 0.75, and the polishing pad rotational speed is Dressing method, characterized in that 90 ~ 150 RPM. 4. The dressing method of claim 3, further comprising supplying deionized water to the polishing pad before and after performing the dressing. The dressing method according to claim 4, wherein the polishing slurry or deionized water is supplied during the dressing, and the flow rate of the polishing slurry or the deionized water is 1-2 L / min. delete

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