KR101070394B1 - Method for producing cvd pad conditioner dull to change of pressure and cvd pad conditioner produced thereby - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conditioner for a CMP pad used in a chemical mechanical polishing (CMP) process, which is essentially applied in a semiconductor device manufacturing process. More specifically, a polishing pad according to a pressure change during conditioning The present invention relates to a pressure change insensitive CVD pad conditioner having a structure in which the amount of wear changes is small.

Description

Conditioning Pressure Change Insensitive CD Pad Conditioner Manufacturing Method and Pressure Change Insensitive CD Pad Conditioner Manufactured by the Method {METHOD FOR PRODUCING CVD PAD CONDITIONER DULL TO CHANGE OF PRESSURE AND CVD PAD CONDITIONER PRODUCED THEREBY}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conditioner for a CMP pad used in a chemical mechanical polishing (CMP) process, which is essentially applied in a semiconductor device manufacturing process. More specifically, a polishing pad according to a pressure change during conditioning The present invention relates to a method for manufacturing a pressure change insensitive CVD pad conditioner having a structure in which the amount of wear changes is small, and a pressure change insensitive CVD pad conditioner manufactured by the method.

The CMP technique used in semiconductor devices is used to planarize thin films such as insulating films and metal films formed on semiconductor wafers by CVD or the like.

In the planarization process using CMP technology, a polishing pad is attached to a rotating platen, and a carrier is held while holding a wafer whose carrier is a polishing object and supplying a slurry onto the pad. It is a processing method in which the surface plate and the carrier are moved relative to each other and polished while pressure is applied to the carrier.

Thus, in CMP technology for planarization, the uniformity of removal rate across the workpiece surface, such as wafers (polishing uniformity) is an important property. Among various factors for improving polishing uniformity, the surface state of the polishing pad may also be an important quantitative factor.

The desired surface condition of the polishing pad is achieved through conditioning of the polishing pad, which is performed by cutting the surface of the deformed pad with a conditioner to restore the worn or clogged pores of the polishing pad and the flattening of the broken polishing pad. Can be.

Here, the conditioning causes the pad conditioner to have a diamond-like grinder in contact with the polishing pad to scrape or rough the surface of the polishing pad, such that the surface state of the new polishing pad is optimized to an initial state with good retention of slurry, or In use, the slurry holding ability of the polishing pad is restored to maintain the polishing ability of the polishing pad.

As such, the conditioning process has the advantage of increasing the surface roughness of the polishing pad surface and opening up pores, but it causes the wear of the polishing pad to shorten its lifespan, and thus the polishing pad's life is dominant in the degree of conditioning. . That is because typically about 95% of the pad wear results from wear with the diamond conditioner, and only about 5% from contact with the workpiece is known.

On the other hand, as an example of a pad conditioner used to process and adjust the polishing pad, as described in Korean Patent No. 10-0387954, a plurality of polygonal pyramids protruding at a uniform height upwards are formed on the surface of the substrate, and A CVD pad conditioner having a structure in which a diamond layer is deposited by CVD on a surface has been developed. The CVD pad conditioner having the above structure can be used at a constant pressure, but the polishing pad is not properly conditioned when the PWR is not stable. In spite of not having a pad wear rate according to the change in the conditioning pressure, that is, the PWR (Pad Wear Rate) was increased or decreased.

The present inventors have completed the present invention as a result of research efforts to solve the above disadvantages and problems of the prior art.

Accordingly, an object of the present invention is to provide a pressure change insensitive CVD pad conditioner manufacturing method and a pressure change insensitive CVD manufactured by the method for improving the conditioning efficiency of the pad due to the structure that does not change the amount of pad wear according to the pressure change during conditioning It is to provide a pad conditioner.

Another object of the present invention is a method of manufacturing a pressure change insensitive CVD pad conditioner and a pressure change insensitive CVD pad manufactured by the method, which can prolong the life of the pad in the long term due to excellent conditioning efficiency, that is, constant maintenance efficiency. To provide a conditioner.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the present invention is a CVD pad conditioner composed of a substrate and a plurality of cutting tips protruding upward on the surface of the substrate, the size, height and number of the cutting tips to adjust It provides a method of manufacturing a pressure change insensitive CVD pad conditioner comprising the step.

In a preferred embodiment, the shape of the cutting tip is formed to have a structure in which a diamond layer is deposited by CVD on the surface of any one of a cylinder, a polygonal pillar, a truncated cone or a truncated pyramid.

In a preferred embodiment, the size of the plurality of cutting tips are 20 to 35um in length and width, respectively, the height is 40 to 60um, the number is adjusted to 2000 to 6000ea.

The present invention also provides a pressure change insensitive CVD pad conditioner, which is produced by the method of any one of claims 1 to 3.

In a preferred embodiment, a plurality of cutting tips are formed on the surface of the pressure change insensitive CVD pad conditioner having a size of 20 to 35 um, a height of 40 to 60 um, and a number of 2000 to 6000 ea, respectively.

The present invention has the following excellent effects.

First, according to the present invention, the conditioning efficiency of the pad may be improved due to the structure in which the pad wear amount is not largely changed according to the pressure change during conditioning.

In addition, according to the present invention, the life of the pad can be extended in the long term due to the excellent conditioning efficiency, that is, the constant maintenance efficiency.

1 is a graph of PWR measurement results according to pressure changes of Example conditioners 1 to 6 and Comparative Example conditioners 1 to 9 prepared according to Comparative Examples 1 to 9 prepared according to Examples 1 to 6 of the present invention;
2 is an enlarged view of a part of the PWR measurement result graph according to the pressure change shown in FIG. 1;
3 is a graph of PWR measurement results of Example conditioners 2, 7 and 8 and Comparative Example conditioners 10 and 11 prepared according to Comparative Examples 10 and 11 according to Examples 2, 7 and 8 of the present invention.

The terms used in the present invention were selected as general terms as widely used as possible, but in some cases, the terms arbitrarily selected by the applicant are included. In this case, the meanings described or used in the detailed description of the present invention are considered, rather than simply the names of the terms. The meaning should be grasped.

Hereinafter, with reference to the preferred embodiment shown in the accompanying drawings will be described in detail the technical configuration of the present invention.

However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Like reference numerals used to describe the present invention throughout the specification denote like elements.

The technical feature of the present invention is to minimize the width of PWR (PAD WEAR RATE) change due to pressure change by adjusting the size, height, and number of cutting tips formed on the surface of the CVD pad conditioner.

That is, when the size, height, and number of cutting tips formed in the CVD pad conditioner have a constant value, it is confirmed that the change in the PWR can be significantly reduced even if the pressure varies considerably.

Therefore, the pressure change insensitive CVD pad conditioner manufacturing method of the present invention is a CVD pad conditioner composed of a substrate and a plurality of cutting tips protruding upward on the surface of the substrate, the size, height and number of the cutting tips Adjusting the.

That is, the pressure-sensitive insensitive CVD pad conditioner of the present invention has a predetermined value and height of the cutting tip formed on its surface at the time of manufacture, it is preferable to be adjusted so that a certain number is formed, more preferably the size is horizontal And the length is 20 to 35um each, the height is 40 to 60um, the number is formed is adjusted to be processed to be 2000 to 6000ea.

Here, the size, height, and number of cutting tips were determined experimentally through countless experiments.

First, if the cutting tip size is less than 20um, the load received by one cutting tip will increase, and the tip may break during use, resulting in wafer scratches.If the cutting tip size is over 35um, the conditioning efficiency is small and high conditioning pressure is required to increase the PWR. Could go.

In addition, when the cutting tip height is less than 40um, the cutting tip height is low, so that the bottom surface of the tip is in contact with the pad, the conditioning efficiency is very low, and when it exceeds 60um, the PWR change with pressure is severe.

Lastly, in the case of the number of cutting tips, the larger the number of tips, the smaller the load per tip, which is stable, but if the number of tips is too large, a decrease in the conditioning efficiency occurred, which required an appropriate number of tips. The PWR change was large with the change, and exceeding 6000ea resulted in conditioning only under very high pressure, resulting in very low conditioning efficiency.

In addition, in the present invention, the shape of the cutting tip is preferably formed to have a structure in which a diamond layer is deposited by CVD on the surface of any one of a cylinder, a polygonal pillar, a truncated cone or a polygonal truncated cone, more preferably a polygonal truncated cone.

As described above, the pressure change insensitive pad conditioner manufactured by adjusting the size, height, and number of cutting tips formed on the surface of the CVD pad conditioner may have a pressure change range of 5 to 13 lbf during conditioning. The change in the pad wear amount is 15 to 20um / hr, thereby effectively increasing the conditioning efficiency, and the longevity of the pad can be increased in the long term due to the excellent conditioning efficiency, that is, the constant conditioning efficiency.

Example 1

On the surface of a disk-shaped substrate having a diameter of 4 inches, a polygonal pyramidal shaped cutting tip having a width of 35 x 35 um and a height of 50 um was formed by a known CVD pad conditioner manufacturing method at 1.95 mm spacing so that the number thereof was 2000ea. A pressure sensitive insensitive CVD pad conditioner 1 (“Example Conditioner 1”) was prepared.

Example 2

A pressure change insensitive CVD pad conditioner 2 (“Example Conditioner 2”) was prepared in the same manner as in Example 1 except that the number of cutting tips formed was 4000ea.

Example 3

A pressure change insensitive CVD pad conditioner 3 (“Example Conditioner 3”) was prepared in the same manner as in Example 1 except that the number of cutting tips formed was 6000ea.

Example 4

A pressure change insensitive CVD pad conditioner 4 (“Example Conditioner 4”) was prepared in the same manner as in Example 1 except that the width and length were set to 20 × 20 μm.

Example 5

A pressure change insensitive CVD pad conditioner 5 (“Example Conditioner 5”) was prepared in the same manner as in Example 2 except that the width and length were set to 20 × 20 μm.

Example 6

A pressure change insensitive CVD pad conditioner 6 (“Example Conditioner 6”) was prepared in the same manner as in Example 3 except that the width and length were set to 20 × 20 μm.

Example 7

A pressure change insensitive CVD pad conditioner 7 (“Example conditioner 7”) was prepared in the same manner as in Example 2 except that the height was 40 μm.

Example 8

A pressure change insensitive CVD pad conditioner 8 (“Example conditioner 8”) was prepared in the same manner as in Example 2 except that the height was 60 μm.

Comparative Example 1

Comparative Example Conditioner 1 was prepared in the same manner as in Example 1 except that the number of cutting tips formed was 1000ea.

Comparative Example 2

Comparative Example Conditioner 2 was prepared in the same manner as in Example 1 except that the number of cutting tips formed was 7000ea.

Comparative Example 3

Comparative Example Conditioner 3 was prepared in the same manner as in Comparative Example 1 except that the width and length were set to 20 × 20 μm.

Comparative Example 4

Comparative Example Conditioner 4 was prepared in the same manner as in Comparative Example 2, except that the width and length were set to 20 × 20 μm.

Comparative Example 5

Comparative Example Conditioner 5 was prepared in the same manner as in Comparative Example 1 except that the width and length were set to 50 × 50 um.

Comparative Example 6

Comparative Example Conditioner 6 was prepared in the same manner as in Comparative Example 5 except that the number of cutting tips formed was 2000ea.

Comparative Example 7

Comparative Example Conditioner 7 was prepared in the same manner as in Comparative Example 5 except that the number of cutting tips formed was 4000ea.

Comparative Example 8

Comparative Example Conditioner 8 was prepared in the same manner as in Comparative Example 5 except that the number of cutting tips formed was 6000ea.

Comparative Example 9

Comparative Example Conditioner 9 was prepared in the same manner as in Comparative Example 5 except that the number of cutting tips formed was 7000ea.

Comparative Example 10

Comparative Example Conditioner 10 was prepared in the same manner as in Example 2, except that the height was 30 μm.

Comparative Example 11

Comparative Example Conditioner 11 was prepared in the same manner as in Example 2, except that the height was 70 μm.

Experimental Example 1

Experiments were carried out to measure PWR according to the conditioning pressures (5 to 15 lbf) of Example Conditioners 1 to 6 and Comparative Example Conditioners 1 to 9, in particular depending on the size and number of cutting tips formed on the CVD pad conditioner. PWR variation was observed and the results are shown in Tables 1 to 3 and FIGS. 1 and 2.

Cutting tip size 35 * 35 * 50 (width X length X height) D / F Comparative Example Conditioner 1 Example Conditioner 1 Example Conditioner 2 Example Conditioner 3 Comparative Example Conditioner 2 5 22 4 0 0 0 7 36 14 3 0 0 9 55 28 12 2 0 11 71 49 25 10 One 13 99 63 41 20 5 15 135 91 59 45 11 D / F at 15um 6.21 8.56 11 D / F at 20um 7.86 10.21 13.02 D / F
margin
(15 ~ 20um / hr) Not applicable due to high conditioning efficiency 1.65 1.65 2.02 Not applicable due to low conditioning efficiency

Cutting tip size 20 * 20 * 50 (width X length X height) D / F Comparative Example Conditioner 3 Example Conditioner 4 Example Conditioner 5 Example Conditioner 6 Comparative Example Conditioner 4 5 25 9 5 2 0 7 37 17 12 7 0 9 53 24 18 15 3 11 68 31 24 23 5 13 81 41 33 30 10 15 109 53 46 39 14 D / F at 15um 5.26 6.46 7.76 D / F at 20um 7.88 9.65 10.26 D / F
margin
(15 ~ 20um / hr) Not applicable due to high conditioning efficiency 2.62 3.19 2.5 Conditioning efficiency
Small
Not applicable

Cutting tip size 50 * 50 * 50 (width X length X height) D / F Comparative Example 5 Comparative Example Conditioner 6 Comparative Example Conditioner 7 Comparative Example Conditioner 8 Comparative Example 9 5 26 10 0 0 0 7 69 37 0 0 0 9 210 83 0 0 0 11 416 320 5 0 0 13 554 450 8 4 0 15 649 562 16 11 2 D / F at 15um 4.97 D / F at 20um 5.73 D / F
margin
(15 ~ 20um / hr) Not applicable due to high conditioning efficiency 0.76 Not applicable due to low conditioning efficiency Not applicable due to low conditioning efficiency Not applicable due to low conditioning efficiency

Example conditioners manufactured by the pressure change insensitive CVD pad conditioner manufacturing method of the present invention from the above-described Tables 1 to 3 and FIGS. 1 and 2 are the pad wear amount according to the conditioning pressure by constantly adjusting the size and number of cutting tips Although it can be seen that the change in the size of the cutting tips and the size and the number of the out of the range of the present invention is sensitive to the pressure change it can be seen that the conditioning efficiency tends to be extremely reduced. Here, the disk D / F margin is a pressure range when showing a PWR of 15 ~ 20um / hr, a large value indicates that it is not sensitive to pressure changes.

Experimental Example 2

In order to determine the optimum height of the cutting tips formed in the CVD pad conditioner, Example Conditioners 2, Example Conditioners 7, Example Conditioners 8, Comparative Example Conditioners 10, and Comparative Example Conditioners 11 having the same size and number but different heights are formed. The experiment was performed to measure the PWR according to the conditioning pressure (5 to 15 lbf) of the PWR, and the variation of the PWR according to the cutting tip height was observed and the results are shown in Table 4 and FIG. 3.

Number of cutting tips 4000ea D / F Comparative Example 10 Example Conditioner 7 Example Conditioner 2 Example Conditioner 8 Comparative Example Conditioner 11 5 0 0 0 2 3 7 0 2 3 5 9 9 2 10 12 14 32 11 5 23 25 27 54 13 11 38 41 44 81 15 18 56 59 63 96 D / F at 15um 9 8.57 8.12 7.12 D / F at 20um 10.53 10.23 9.92 7.95 D / F
margin
(15 ~ 20um / hr) Not applicable due to low conditioning efficiency 1.53 1.66 1.8 0.83

The height of the cutting tip formed on the surface of the CVD pad conditioner of the present invention from Table 4 and Figure 3 is suitable for 40 to 60um, it can be seen that the conditioning efficiency is small or pressure-sensitive when out of a predetermined range.

The results of the above experiments show that the pressure change insensitive CVD pad conditioner with a constant size, a constant height, and a certain number of cutting tips according to the manufacturing method of the present invention changes the process pressure generated during conditioning due to a small change in the pad wear amount according to the pressure change. Nevertheless, the PWR value remains stable and can be used stably. As a result, when the pressure-sensitive insensitive CVD pad conditioner of the present invention is carried out in a polishing pad conditioning operation, there is an effect of maintaining a constant conditioning even with a small process change (pressure change).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, Various changes and modifications will be possible.

Claims (5)

In the CVD pad conditioner comprising a substrate and a plurality of cutting tips protruding upward on the surface of the substrate,
The cutting tip is formed to have a structure in which a diamond layer is deposited by CVD on a surface protruding in the shape of a cylinder, a polygonal pillar, a truncated cone or a truncated pyramid.
Including adjusting the size, height and number of the cutting tips,
Method for producing a pressure-sensitive insensitive CVD pad conditioner, characterized in that the change in pad wear amount in the pressure change range of 5 ~ 13 lbf when the condition is 15 to 20um / hr.
delete The method of claim 1,
The plurality of cutting tip size is 20 to 35um in width and length, respectively, 40 to 60um in height, the number of the pressure change insensitive CVD pad conditioner, characterized in that the number is adjusted to 2000 to 6000ea.
A pressure change insensitive CVD pad conditioner manufactured by the manufacturing method according to claim 1 or 3, wherein the pad wear variation ranges from 15 to 20 um / hr in a pressure change range of 5 to 13 lbf during conditioning.
The method of claim 4, wherein
The pressure change ratio of the pressure sensitive non-sensitized CVD pad conditioner is formed with a plurality of cutting tips having a size of 20 to 35 um, a height of 40 to 60 um, and a number of 2000 to 6000 ea, respectively, on the surface of the CVD pad conditioner. Sensitive CVD Pad Conditioner.

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