KR20220009864A - Polishing pad including porous protruding pattern and polishing apparatus including the same - Google Patents

Abstract

The present invention provides a polishing pad for improving polishing rate and reducing manufacturing cost at the same time by including a porous protrusion pattern, and a polishing apparatus including the same. The polishing pad comprises: a support layer; and a pattern layer which is directly disposed on the support layer and includes a protrusion pattern having a plurality of pores. The pores contributes to increase a circumference length on a plane of the protrusion pattern. The circumference length of a polishing surface formed by the protrusion pattern per unit area ranges from 1.0 mm/mm^2 to 50.0 mm/mm^2.

Description

A polishing pad including a porous protrusion pattern, and a polishing apparatus including the same

The present invention relates to a polishing pad including a protruding pattern formed on a polishing surface, and a polishing apparatus including the same. More particularly, it relates to a polishing pad including a protruding pattern having porosity to improve a polishing rate and reduce manufacturing cost, and a polishing apparatus including the same.

In general, a chemical mechanical polishing (CMP) process is involved for manufacturing a high-integration circuit device such as a semiconductor or a display. In the chemical mechanical polishing process, a polishing target substrate, for example, a wafer substrate, is brought into pressure contact with a rotating polishing pad, and polishing is performed using a chemical reaction with a slurry at the same time. The chemical mechanical polishing process mainly aims to planarize the surface to be polished or to remove unnecessary layers.

The characteristics of the polishing process may be expressed in terms of a removal rate (RR), non-uniformity (NU), scratch of the polishing object, and planarization of the polishing object. Among them, the polishing rate is one of the most important characteristics of the polishing process, and the main factors are the polishing surface morphology (topography) of the polishing pad, the slurry composition, and the temperature of the polishing platen.

A conventional polishing apparatus is configured to include a conditioner to maintain the surface of the polishing pad, that is, the polishing surface characteristics. The conditioner may be positioned eccentrically with respect to the axis of rotation of the polishing pad, and the conditioner may be configured to be in contact with the polishing surface of the polishing pad. Cutting particles made of diamond or the like are disposed on a surface of the conditioner in contact with the polishing pad, and an uneven structure may be formed or maintained on the surface of the polishing pad by the cutting particles. That is, in the course of the polishing process, the conditioner continuously polishes the polishing surface of the polishing pad to maintain the surface roughness of the polishing pad at a certain level or more, and the polishing apparatus including the polishing pad has an approximately constant polishing rate. can be made to indicate

However, as the polishing process is performed, the polishing pad is continuously worn, and the uneven structure of the surface and the uneven surface roughness may occur. If the surface roughness is too small, there is a problem in that the actual contact area actually in contact with the substrate to be polished increases or the flow of the polishing liquid slurry becomes difficult. On the other hand, if the surface roughness is excessively large, the required flatness may not be satisfied due to non-uniform contact with the polishing target substrate, and scratches may occur on the polishing target. The unevenness of the polishing surface is a factor that shortens the life and durability of the polishing pad.

In particular, as pattern substrates such as semiconductors are highly integrated, the above problems may be exacerbated. For example, in order to form a shallow trench isolation (STI) structure for high integration of semiconductors, a degree of planarization at the level of global planarization is required, and the polishing process may directly affect semiconductor properties.

However, in the case of a conventional polishing pad, there is a problem in that it is vulnerable to defects such as dishing and erosion due to durability problems. can cause Therefore, there is an urgent need for the development of a polishing pad applicable to a case requiring a high level of planarity, such as a shallow trench isolation process.

Accordingly, an object of the present invention is to provide a polishing pad capable of exhibiting a stable morphology or topography of a polishing surface despite the continued polishing process. Another object of the present invention is to provide a polishing pad that has excellent polishing rate and uniformity, and can improve the use efficiency of the polishing liquid slurry.

Further, it is an object to provide a polishing pad capable of controlling the polishing rate according to a polishing object from a factor newly discovered as being capable of affecting the polishing rate.

At the same time, it is to provide a polishing pad that can be manufactured at a lower cost in spite of the improved polishing properties as described above.

Another object of the present invention is to provide a polishing apparatus including a polishing pad which has excellent polishing rate and uniformity and can improve the use efficiency of polishing liquid slurry.

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

A polishing pad according to an embodiment of the present invention for solving the above problems includes a support layer; and a pattern layer disposed directly on the support layer, the pattern layer including a protrusion pattern having a plurality of pores, wherein the pores contribute to an increase in a perimeter length in a plane of the protrusion pattern, and the protrusion pattern per unit area The peripheral length of the polishing surface to be formed is in the range of ^{1.0 mm/mm 2} to 50.0 mm/mm ^{2 .}

The rigidity of the pattern layer may be greater than that of the support layer.

In a plan view, a ratio of the area occupied by the pores to the total area of the upper surface of any one protrusion pattern may be 10% to 50%.

In addition, the peripheral length of any one of the protruding patterns may be 4 to 50 times the minimum width of the any of the protruding patterns.

The circumferential length of the polishing surface formed by the protruding pattern per unit area may be in the range of 0.1 to 1.0 times the reciprocal of the minimum width of a certain protruding pattern.

The circumferential length of any protrusion pattern may be increased by 1.5 to 3.5 times compared to the circumferential length when the first void does not exist.

The minimum width of the protrusion pattern may be 20 μm or more, and the average diameter of the pores may be in the range of 10 μm to 150 μm.

In a plan view, the area occupied by the pores per unit area may be 0.5% to 20%.

In a plan view, the actual polishing area of the protruding pattern may be 5% to 30% per unit area.

In addition, the voids may include a third void that is positioned on the side surface of the protrusion pattern to form a side groove of the protrusion pattern, contributes to an increase in the lateral area, and affects the flow of the slurry during the polishing process.

The average diameter of the third pores may be in the range of 20 μm to 150 μm.

The porosity of the support layer may be different from the porosity of the pattern layer.

A polishing apparatus according to an embodiment of the present invention for solving the above another problem is a polishing platen configured to rotate; and a polishing pad disposed on the polishing platen.

A method of manufacturing a polishing pad according to an embodiment of the present invention for solving another problem includes: determining a contact pressure required for polishing and a planar shape and length element of a protruding pattern; determining a polishing area of the protruding pattern in contact with the polishing target substrate in consideration of the contact pressure; determining a circumferential length per unit area of the protrusion pattern in consideration of the contact pressure and the determined polishing area; and manufacturing a pattern layer including the protruding pattern.

The pattern layer may include a protrusion pattern having a plurality of pores, and the pores may contribute to an increase in a perimeter of the protrusion pattern. The voids can contribute to an increase in the circumferential length of the protruding pattern, and also serve to reduce the polishing area, so that the real contact pressure can be improved under the same polishing load.

In addition, in the step of manufacturing the pattern layer, the length element of the manufactured protrusion pattern may be greater than the determined length element.

Before the step of manufacturing the pattern layer, the step of determining the size of the pores included in the protrusion pattern may be further included.

Details of other embodiments are included in the detailed description.

According to embodiments of the present invention, it is possible to stably maintain the surface roughness or topography of the polished surface despite the continuous polishing process, and to improve the polishing rate and polishing uniformity. In addition, even if the surface of the object to be polished has a fine curve, it is possible to follow the curve in the vertical direction along the curve of the surface of the object, thereby improving the polishing rate and polishing uniformity.

In addition, the polishing rate can be controlled from factors such as the pattern structure of the polishing pad surface, the length of the pattern, and the contact surface of the pattern, and the use of the slurry through the shape and arrangement of the unique protruding pattern according to the embodiments of the present invention can improve efficiency

Moreover, as described above, while elements such as the structure, length, and/or contact area of the protruding pattern are configured to satisfy within a predetermined range, the protruding pattern has a pore size of a specified size so that the edge forming the pores is the perimeter of the protruding pattern may contribute to the increase. Accordingly, it is possible to achieve simplification of process equipment for forming the protruding pattern, and contribute to reduction in manufacturing cost of the polishing pad and the polishing apparatus.

Effects according to the embodiments of the present invention are not limited by the contents exemplified above, and more various effects are included in the present specification.

1 is a perspective view of a polishing apparatus according to an embodiment of the present invention.
FIG. 2 is a plan layout of the polishing pad of FIG. 1 ;
3 is an enlarged perspective view showing an enlarged portion A of FIG. 2 .
4 is a plan view illustrating an arrangement of the protrusion pattern of FIG. 2 .
FIG. 5 is an enlarged perspective view showing an enlarged protrusion pattern of FIG. 2 .
6 is a cross-sectional view taken along line BB′ of FIG. 2 .
7 is a schematic diagram illustrating a state in which the polishing pad of FIG. 2 is in contact with a polishing target substrate, and FIG. 8 is a schematic diagram compared with FIG. 7 .
9 is another schematic diagram illustrating a state in which the polishing pad of FIG. 2 is in contact with a polishing target substrate, and FIG. 10 is a schematic diagram compared with FIG. 9 .
11 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.
12 to 18 are plan views illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to still another exemplary embodiment of the present invention.
19 is an image showing the results according to Experimental Example 1.
20 and 21 are images showing results according to Experimental Example 2.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only the embodiments allow the disclosure of the present invention to be complete, and those of ordinary skill in the art to which the present invention pertains. It is provided to fully inform the person of the scope of the invention, and the present invention is only defined by the scope of the claims. That is, various changes may be made to the embodiments presented by the present invention. It should be understood that the embodiments described below are not intended to limit the embodiments, and include all modifications, equivalents, and substitutes thereto.

The size, thickness, width, length, etc. of the components shown in the drawings may be exaggerated or reduced for convenience and clarity of description, so that the present invention is not limited to the illustrated form.

Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.

Spatially relative terms 'above', 'upper', 'on', 'below', 'beneath', 'lower', etc. As illustrated, it may be used to easily describe a correlation between one element or components and another device or components. Spatially relative terms should be understood as terms including different orientations of the device when used in addition to the orientations shown in the drawings. For example, when an element shown in the drawing is turned over, an element described as 'below or beneath' of another element may be placed 'above' of the other element. Accordingly, the exemplary term 'down' may include both the direction of the bottom and the top.

In this specification, 'and/or' includes each and every combination of one or more of the recited items. The singular also includes the plural, unless the phrase specifically states otherwise. As used herein, 'comprises' and/or 'comprising' does not exclude the presence or addition of one or more other components in addition to the stated components. Numerical ranges indicated using 'to' indicate numerical ranges including the values stated before and after them as lower and upper limits, respectively. 'About' or 'approximately' means a value or numerical range within 20% of the value or numerical range recited thereafter.

In this specification, the first direction (X) means an arbitrary direction in a plane, and the second direction (Y) means another direction intersecting the first direction (X) in the plane. In addition, the third direction Z means a direction perpendicular to the plane. Unless otherwise defined, 'plane' means a plane to which the first direction (X) and the second direction (Y) belong. In addition, unless otherwise defined, 'overlapping' means that the components overlap in the third direction (Z) in the plane view.

As used herein, the term 'protrusion pattern' refers to a structure having a shape protruding from a certain reference plane. The planar arrangement of the pattern may be regular or irregular. A plurality of protrusion patterns are gathered to form a cluster pattern of a specific shape, and even when the cluster patterns are substantially regularly arranged, the term protrusion pattern means any one of a plurality of protrusion patterns forming one cluster pattern can be used as

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of a polishing apparatus according to an embodiment of the present invention.

Referring to FIG. 1 , the polishing apparatus 1 according to the present embodiment includes a polishing platen 10 connected to a rotating shaft and a polishing pad 11 disposed on the polishing platen 10 , and the polishing pad 11 . ) may further include a nozzle 60 and/or a carrier 40 for supplying the slurry 70 on the polishing surface. Although the present invention is not limited thereto, in the polishing apparatus 1 according to the present embodiment, a conditioner for adjusting the surface roughness of the polishing surface of the polishing pad 11 may be unnecessary.

The abrasive platen 10 is configured in a substantially circular plate shape and can rotate, for example, in a counterclockwise direction. Further, the polishing platen 10 can stably support the polishing pad 11 thereon. That is, the abrasive platen 10 may provide a function such as a rotary table.

The polishing pad 11 may be disposed on the polishing platen 10 . An upper surface of the polishing pad 11 in contact with the polishing target substrate 50 may form a polishing surface. Although not shown in FIG. 1 , fine-sized patterns and/or trenches may be formed on the polishing surface, that is, the upper surface of the polishing pad 11 . The shape, morphology or topology of the polishing surface of the polishing pad 11 will be described later in detail with FIG. 2 and the like.

The polishing target substrate 50 may be in a fixed position by being eccentric with the rotation axis of the polishing platen 10 or the rotation axis of the polishing pad 11 . The polishing target substrate 50 may be in a state of being fixed by the carrier 40 connected to the rotation shaft and rotating by the carrier 40 . The rotation direction of the polishing target substrate 50 may be the same as the rotation direction of the polishing pad 11 , but the present invention is not limited thereto, and the rotation direction of the polishing target substrate 50 and the polishing pad 11 is opposite. It could be a direction. The polishing target substrate 50 to be polished in contact with the polishing pad 11 may be, for example, a semiconductor wafer substrate or a display substrate, but the present invention is not limited thereto.

The nozzles 60 may be spaced apart from the polishing pad 11 to supply the slurry 70 to the polishing surface of the polishing pad 11 . In the present specification, the term 'slurry' may be used to have substantially the same meaning as abrasive liquid or abrasive particles. The slurry 70 flows on the polishing surface of the polishing pad 11 by centrifugal force generated by the rotation of the polishing pad 11 , and at least a portion of the slurry 70 penetrates between the polishing pad 11 and the polishing target substrate 50 . It can contribute to polishing through chemical reactions.

Hereinafter, the polishing pad 11 will be described in more detail with further reference to FIGS. 2 to 6 . FIG. 2 is a plan layout of the polishing pad of FIG. 1 ; 3 is an enlarged perspective view showing an enlarged portion A of FIG. 2 . 4 is a plan view illustrating an arrangement of the protrusion pattern of FIG. 2 . FIG. 5 is an enlarged perspective view showing an enlarged protrusion pattern of FIG. 2 . 6 is a cross-sectional view taken along line B-B' of FIG. 2 .

2 to 6 , the polishing pad 11 according to the present embodiment may have a substantially circular shape in a plan view. Also, the polishing pad 11 may include a support layer 100 and a pattern layer 200 disposed on the support layer 100 . The upper surface of the pattern layer 200 may form a polishing surface as a whole. The support layer 100 and the pattern layer 200 may each include a material having a predetermined flexibility.

In an exemplary embodiment, the strength, rigidity, and/or hardness of the support layer 100 may be less than that of the pattern layer 200 . That is, the support layer 100 may have greater flexibility and a smaller modulus of elasticity than the pattern layer 200 . The elastic modulus is meant to include a loss modulus and/or a storage modulus.

Through this, when the surface of the polishing target substrate 50 has a fine curve, when the planarization characteristic required for the polishing target substrate 50 is high, and/or even when the polishing pad 11 has a fine curve, the polishing pad The protrusion pattern 230 formed on the upper surface of (11) may be in close contact along the curvature of the polishing target substrate 50 to perform polishing. That is, the polishing pad 11 may follow the surface of the polishing target substrate 50 . This will be described later in conjunction with FIG. 7 and the like.

The support layer 100 and the pattern layer 200 may be made of the same or different materials. As a non-limiting example, the support layer 100 and the pattern layer 200 may include substantially the same polymer material. Examples of the polymer material include (poly) urethane (PU), (poly) (meth) acrylate ((poly) (meth) acrylate), (poly) epoxy, acrylo Nitrile butadiene styrene (ABS), (poly) etherimide ((poly) etherimide), (poly) amide ((poly) amide), (poly) propylene ((poly) propylene), (poly) butadiene ((poly) butadiene ), polyalkylene oxide, (poly) ester ((poly) ester), (poly) isoprene ((poly) isoprene), (poly) styrene ((poly) styrene), (poly) ethylene ( (poly)ethylene), (poly)carbonate ((poly)carbonate), polyfluorene, polyphenylene, polyazulene, polypyrene, polynaphthalene, poly-p-phenylenevinylene, polypyrrole, polycarbazole, poly indole, polyaniline, or combinations thereof. The rigidity of the support layer 100 and the pattern layer 200 may be controlled through the degree of crosslinking of the polymer material, but the present invention is not limited thereto.

The support layer 100 may have a substantially circular shape in a plan view, and may provide a function of supporting the pattern layer 200 thereon. The lower limit of the minimum thickness T1 of the support layer 100 may be about 1 mm or more, or about 2 mm or more, or about 3 mm or more. When the thickness of the support layer 100 is smaller than the above range, the support layer 100 may not exhibit sufficient elasticity or strain, and it may be difficult for the polishing pad 11 to follow the curve of the substrate 50 to be polished. The upper limit of the thickness of the support layer 100 is not particularly limited, but may be, for example, about 5 mm or less, or about 4 mm or less. In the present specification, when a plurality of upper and lower limits of a numerical range are described, the numerical range disclosed herein is a numerical range between any upper limit arbitrarily selected from among a plurality of upper limits and a lower limit of any one arbitrarily selected from among a plurality of lower limits. should be understood as disclosing.

In some embodiments, the porosity of the support layer 100 may be different from the porosity of the pattern layer 200 to be described later. As a non-limiting example, the support layer 100 may have a higher porosity than the pattern layer 200 to be described later, specifically, the protrusion pattern 230 . For example, the porosity of the support layer 100 may be about 1.3 times or more, or about 1.4 times or more, or about 1.5 times or more of the porosity of the pattern layer 200 . As described above, the support layer 100 may have greater flexibility than the pattern layer 200 . In order to implement this, the type of material, physical properties, etc. may be controlled, but may also be controlled using the porosity. However, the present invention is not limited thereto, and in another embodiment, the porosity of the support layer 100 may be smaller than the porosity of the pattern layer 200 .

The pattern layer 200 may be disposed on the support layer 100 . In an exemplary embodiment, the pattern layer 200 may be directly disposed on the support layer 100 without a separate bonding layer. The pattern layer 200 may include a base 210 and a plurality of protruding patterns 230 disposed on the base 210 . A plurality of protrusion patterns 230 may be spaced apart from each other on the base 210 .

The base 210 and the protrusion pattern 230 are integrally and continuously formed without a physical boundary, and may be made of the same material. In another embodiment, the base 210 and the protrusion pattern 230 may have a physical boundary and may be made of different materials. In this case, the strength, rigidity, and/or hardness of the base 210 may be smaller than that of the protrusion pattern 230 .

The base 210 may be a portion overlapping the plurality of protruding patterns 230 spaced apart from each other in the third direction (Z). In addition, the base 210 may be a portion that occupies most of an area corresponding to the polishing pad 11 in a plan view and covers the support layer 100 . Alternatively, the base 210 may mean the remaining portion of the pattern layer 200 excluding the protrusion pattern 230 to be described later.

The lower limit of the maximum thickness T2 of the base 210 may be about 0.01 mm or more, or about 0.05 mm or more, or about 0.1 mm or more, or about 0.5 mm or more, or about 1.0 mm or more. When the thickness of the base 210 is smaller than the above range, it may be difficult for the polishing pad 11 to follow the curve of the substrate 50 to be polished. The upper limit of the thickness of the base 210 is not particularly limited, but may be, for example, about 3.0 mm or less, or about 2.5 mm or less, or about 2.0 mm or less, or about 1.5 mm or less.

The plurality of protrusion patterns 230 may be disposed on one base 210 . The protrusion pattern 230 may be a portion that forms the uppermost level of the polishing pad 11 and forms a polishing surface. That is, even when the pattern layer 200 has a multi-stage structure, the protruding pattern 230 may mean a protruding portion contributing to actual polishing.

In an exemplary embodiment, the protrusion pattern 230 may have a substantially rectangular shape in a plan view, but the present invention is not limited thereto. In addition, the protrusion pattern 230 may have a substantially rectangular shape, and may not overlap the trenches 300 to be described later in the third direction (Z). For example, the protrusion pattern 230 is not formed at a position overlapping the trench 300 , or the already formed protrusion pattern 230 may be removed and processed using a laser or the like.

In addition, although FIG. 2 illustrates a state in which the plurality of protrusion patterns 230 are substantially regularly arranged in a plan view, in another embodiment, the plurality of protrusion patterns 230 are substantially irregularly arranged, or arbitrary may have a random arrangement of In another embodiment, the plurality of protrusion patterns 230 may be gathered to form one cluster pattern, and the cluster patterns may be arranged substantially regularly. In this case, the plurality of protrusion patterns 230 in a certain cluster pattern may be arranged with regularity.

In the present embodiment, the protrusion patterns 230 may be repeatedly arranged along at least two directions to form a regular arrangement. For example, the protrusion patterns 230 may be repeatedly arranged with substantially the same spacing along the first direction X and the second direction Y to be approximately arranged in a matrix.

The size of the protrusion pattern 230 may be a major factor affecting a polishing rate, a polishing non-uniformity NU, and the like of the polishing pad 11 . The inventors of the present invention have completed the present invention by confirming that the polishing rate can be controlled by the circumferential length and/or area of the protruding pattern 230 .

In an exemplary embodiment, in a plan view, the polished area occupied by the protruding pattern 230 , or the actual polished area, that is, the area occupied by the upper surface of the protruding pattern 230 , is about 1.0% or more and 80% or less of the total area, or about 1.0% or more and 70% or less, or about 1.0% or more 60% or less, or about 1.0% or more 50% or less, or about 1.0% or more 45.0% or less, or about 1.0% or more 40% or less, or about 1.0% or more 35 % or less, or about 1.0% or more and 30% or less, or about 3.0% or more and 30.0% or less, or about 5.0% or more and 30.0% or less, or about 10.0% or more and 30.0% or less. That is, the lower limit of the polishing area with respect to the total area may be about 1.0%, or about 3.0%, or about 5.0%. The upper limit of the abrasive area to the total area may be about 80%, or about 70%, or about 60%, or about 50%, or about 45%, or about 40%, or about 35%, or about 30%. .

As used herein, the term 'polishing area' or 'actual polishing area' refers to an area where the upper end of the protrusion pattern 230 comes into contact with the substrate 50 to be polished and contributes to polishing. That is, it means an area occupied by a portion forming the maximum height in the pattern layer 200 of the polishing pad 11 . The polishing area may be calculated as the sum of the upper areas of the protruding patterns 230 with respect to the total area of the polishing pad 11 . The sum of can also be used with substantially the same meaning.

Also, as will be described later, the protrusion pattern 230 may have a first void P1 and a second void P2 that contribute to an increase in the peripheral length of the edge. In this case, the area occupied by the above-described protrusion pattern 230 may mean an area excluding the area occupied by the first void P1 and the second void P2 . The first gap P1 and the second gap P2 will be described in detail later.

For example, as shown in FIG. 4 , when the planar shape of a certain protrusion pattern 230 is an approximately square shape with one side length W, the planar area occupied by the protrusion pattern 230 is W×W It may be an area excluding the area occupied by the first void P1 and the second void P2 . Accordingly, the area S occupied by the protrusion pattern 230 may be slightly smaller than W×W. Specifically, the polishing area S formed by any one protrusion pattern 230 may be (W×W)−(area occupied by the first void + area occupied by the second void).

As another example, when the planar area occupied by any one protrusion pattern 230 is expressed as S, the ratio of the polishing area to the total planar area of the polishing pad 11 may be expressed as S×n. have. Here, n is the total number of protrusion patterns 230 included in the polishing pad 11 .

As another example, the ratio of the polishing area may be expressed as an area occupied by the protrusion patterns 230 belonging to the verification target area with respect to an arbitrary verification target area of the polishing pad 11 . In this case, when the area to be checked (eg, inspection area) is the x-axis and the area occupied by the protrusion pattern 230 in that case is the y-axis, the ratio of the polishing area is expressed as a slope of the graph. may be

When the above-described ratio (%) of the polishing area is within the above range, an excellent polishing rate is exhibited, and polishing characteristics such as a polishing rate can be controlled by changing the arrangement, shape, and/or size of the protruding pattern 230 . In addition, when the polishing area is too large, the polishing rate may decrease.

On the other hand, in a unit area of a plane view, for example, 1 mm ² , the perimeter length per unit area formed by the planar perimeter of the protrusion pattern 230 is about 1.0 mm/mm ² or more and 250.0 mm/mm ² or less, or about 1.0 mm/ mm ² or more 200.0mm / mm ² or less, or about 1.0mm / mm ² or more 150.0mm / mm ² or less, or about 1.0mm / mm ² or more 100.0mm / mm ² or less, or about 1.0mm / mm ² or more 50.0mm /mm ² or less, or about 1.0 mm/mm ² or more and 30.0 mm/mm ² or less, or about 1.0 mm/mm ² or more and 25.0 mm/mm ² or less, or about 1.0 mm/mm ² or more and 20.0 mm/mm ² or less; or about 1.0mm / mm ² or more 16.0mm / mm ² or less, or about 1.0mm / mm ² or more 10.0mm / mm ² or less, or about 3.0mm / mm ² or more 10.0mm / mm ² or less, or about 5.0mm / mm ² or more and 10.0 mm/mm ² or less.

As used herein, the term 'perimeter length per unit area' refers to an outer length formed by the polishing area of the protruding patterns 230 per ^{unit area (1 mm 2 ).}

For example, if it is assumed that the entire rectangle shown in FIG. 4 has ^{an area of 1 mm 2} , the perimeter length per unit area may be expressed as four protruding patterns×L. Here, L denotes a perimeter length formed by any one protrusion pattern 230 . For example, L may be somewhat larger than 4 sides×W. This is because, as described above, the first void P1 and the second void P2 cause an increase in the circumferential length of the protruding pattern 230 . That is, in the present specification, the circumferential length of the protruding pattern 230 is a closed curve formed by an edge including the first void P1 of the protruding pattern 230 having an arbitrary shape on a plane as well as an outer edge. It is formed including the circumferential length of the second air gap (P2) located inside the.

As another example, the perimeter length per unit area may be expressed as a perimeter length formed by the protrusion pattern 230 belonging to the confirmation object area with respect to an arbitrary confirmation object area of the polishing pad 11 . In this case, when the area to be checked (eg, inspection area) is the x-axis and the total perimeter length formed by the protrusion pattern 230 in that case is the y-axis, the perimeter per unit area is the slope of the graph may be expressed as

When the above-described peripheral length per unit area (mm/mm ² ) is in the above range, an excellent polishing rate may be exhibited. This will be described later along with experimental examples and the like.

In an exemplary embodiment in which the protrusion pattern 230 is substantially rectangular in plan view, the maximum width Wmax of the protrusion pattern 230 may be formed in a substantially diagonal direction. On the other hand, the minimum width W of the protrusion pattern 230 may correspond to the length of any one side. In the present specification, the minimum width of the protrusion pattern means the width of the portion having the smallest length among the length, width or width on a plane of any one protrusion pattern 230 that is physically separated and spaced apart from other protrusion patterns. do. In addition, the minimum width means the minimum length required to be controlled in the process and/or process equipment for forming the protrusion pattern 230, and may mean the shortest distance between one point and another point, excluding the length increased by the gap. have.

The maximum width Wmax of the protrusion pattern 230 may vary depending on the planar shape of the protrusion pattern 230 , but, for example, the maximum width Wmax of the protrusion pattern 230 is about 1.0 mm or less, or about 0.8 mm or less. , or about 0.5 mm or less, or about 0.3 mm or less.

The minimum width of the protrusion pattern 230 may correspond to the length W of one side. The lower limit of the minimum width W of the protrusion pattern 230 is about 20 μm or more, or about 30 μm, or more, or about 40 μm or more, or about 50 μm or more, or about 60 μm or more, or about 70 μm or more, or about 80 μm or more, or about 90 μm or more, or about 100 μm or more. The upper limit of the minimum width W is not particularly limited, but may be less than the maximum width Wmax.

The height H of the protrusion pattern 230 may affect the polishing characteristics and durability of the polishing pad 11 . The minimum height H of the protrusion pattern 230 means the shortest vertical distance from the upper surface of the base 210 to the upper end of the protrusion pattern 230 . The minimum height H of the protrusion pattern 230 is about 0.01 mm or more and 1.5 mm or less, or about 0.01 mm or more and 1.0 mm or less, or about 0.01 mm or more and 0.5 mm or less, or about 0.01 mm or more and 0.3 mm or less, or about 0.01 mm or more and 0.2 mm or less, or about 0.01 mm or more and 0.1 mm or less.

The height H of the protrusion pattern 230 may be correlated with the minimum width W of the protrusion pattern 230, for example, if the height H of the protrusion pattern 230 exceeds 1.5 mm. When the polishing pad 11 rotates and comes into close contact with the substrate 50 to be polished, inclination or distortion in a planar direction, for example, in any direction within the plane to which the first direction (X) and the second direction (Y) belong, is may occur and may not be able to fully perform the designed abrasion. On the other hand, if the height H of the protruding pattern 230 is less than 0.01 mm, the life of the polishing pad 11 may be too short due to damage or abrasion occurring at the top of the protruding pattern 230 as the polishing process is repeated. can

As described above, the protrusion pattern 230 may have porosity and a plurality of pores P. The plurality of voids P may include a first void P1 , a second void P2 , and a third void P3 .

The first void P1 is exposed on the upper surface of the protrusion pattern 230 , and is located at the edge of the protrusion pattern 230 in a plan view and refers to a void contributing to an increase in the circumferential length L . That is, the first void P1 may form a recess at the edge of the plane of the protrusion pattern 230 . The first gap P1 may have a shape such as a circular arc or an elliptical arc in a plan view.

The second void P2 is exposed on the upper surface of the protruding pattern 230, that is, the polishing surface, and the first void ( It may be the same as P1). On the other hand, the second void P2 is not a shape forming an indentation like the first void P1, but is an approximately circle, an ellipse, or a closed curve shape such as a distorted circle or oval shape from a plan view point of the first void P1. is different from

In an exemplary embodiment, in a plan view, the area occupied by the pores exposed on the upper portion of the protrusion pattern 230 with respect to the entire upper surface of any one protrusion pattern 230, that is, the first void P1 and the second void ( The proportion of the area occupied by P2) is about 10% to 80%, or about 10% to 70%, or about 10% to 60%, or about 10% to 50%, or about 20% to 40%, or about 25 % to 35%.

In other words, in any one of the protruding patterns 230 , the polishing area S formed by the aforementioned one protruding pattern is about 20% to 90% of the apparent area of the one protruding pattern, for example, (W×W). %, or between about 30% and 90%, or between about 40% and 90%, or between about 50% and 90%, or between about 60% and 80%, or between about 65% and 75%.

The first voids P1 and the second voids P2 may be substantially uniformly distributed. When too many first voids P1 and second voids P2 are formed, that is, when the arrangement density is too high, too many first voids P1 located at the edge may be formed. In this case, the upper surface of the protruding pattern 230 , that is, the polished surface may not have a complete shape, and durability may be reduced, such as the protruding pattern 230 is collapsed during the polishing process. On the other hand, when the first and second pores P1 and P2 are too small, an increase in the length of the edge of the protrusion pattern 230 may be insignificant.

In the process of manufacturing the polishing pad 11 including the protruding pattern 230 having porosity according to the present embodiment, first, the contact pressure required for polishing and the planar shape and length elements of the protruding pattern 230 are determined, , the size of the pores P included in the protrusion pattern 230 may be determined. In addition, a polishing area, ie, an upper area, of the protrusion pattern 230 may be determined in consideration of the contact pressure. Then, the perimeter length per unit area of the protruding pattern 230 is determined in consideration of the determined contact pressure and the polishing area, and accordingly, the polishing pad 11 including the pattern layer 200 including the protruding pattern 230 is manufactured. can do.

In this case, as described above, it is not easy to simultaneously control the factors affecting the polishing rate, that is, the ratio of the polishing area of the protruding pattern 230 and the perimeter length per unit area. In particular, there is a limit in increasing the perimeter length per unit area in a state in which the required polishing area is determined. If the perimeter length is increased by changing the pattern shape, it may cause a reduction in the polishing area, or at least increase the manufacturing cost due to a reduction in the minimum width of the pattern.

However, according to the present embodiment, it is possible to relatively easily achieve an increase in the perimeter length per unit area while substantially maintaining the polishing area using the pores P of the protrusion pattern 230 . When the first void P1 and the second void P2 have the area ratio of the first void P1 and the second void P2 as described above, the first void P1 and the second void P2 causing an increase in the circumferential length do not exist Compared to that, the circumferential length of the protrusion pattern 230 according to the present embodiment having the first void P1 may be increased by about 1.5 times to 3.5 times, or about 2.0 times to 3.0 times, or about 2.2 times to 2.7 times.

In addition, some differences may occur depending on the planar shape of the protrusion pattern 230 , but as in the present embodiment, the protrusion pattern 230 has edges extending in the first direction (X) and the second direction (Y). In this case, the total perimeter length of any one protrusion pattern 230 is about 4 to 50 times, or about 5 to 50 times, or about 8 to 40 times the minimum width W of the protruding pattern 230 . , or about 10 to 30 times, or about 15 to 25 times.

Alternatively, the circumferential length formed by the protrusion pattern 230 per unit area is about 0.1 to 1.0 times, or about 0.2 to 0.9 times, or about 0.3 the reciprocal of the minimum width W of any one of the protruding patterns 230 . times to 0.8 times.

Meanwhile, as described above, the lower limit of the ratio of the polishing area occupied by the protruding patterns 230 to the total area of the polishing pad 11 is about 1.0%, or about 3.0%, or about 5.0%, or about 10%, and the upper limit is about 10%. may be about 80%, or about 70%, or about 60%, or about 50%, or about 45%, or about 40%, or about 35%, or about 30%.

In this case, the ratio of the area occupied by the first voids P1 and the second voids P2 to the total area of the polishing pad 11 , or the area occupied by the first voids P1 and the second voids P2 per unit area The proportion of may be about 0.01% to 25%, or about 0.5% to 20%, or about 1.0% to 15%.

Although the present invention is not limited thereto, in some embodiments, voids may exist in the remaining portion of the pattern layer 200 except for the protruding pattern 230 , that is, on the surface of the base 210 . However, according to the definition of the first void P1 and the second void P2 described above, the area occupied by the first void P1 and the second void P2 excluding the void on the surface of the base 210 and the inspection area (units) area) or the ratio of the total area of the polishing pad 11 may be within the above range.

In addition to the ratio of the upper area (ie, the actual polished area) of the protruding pattern 230 and the perimeter per unit area as factors affecting the polishing rate, the inventors of the present invention found that the protruding pattern 230 is a predetermined The element in the case of having the pores (P) larger than the size was discovered and the present invention was completed. That is, the area occupied by the pores P as described above, the area occupied by the pores P with respect to the total area, and the area ratio of the upper area of the protrusion pattern 230 excluding the area occupied by the pores P are When it is within the above range, excellent polishing properties may be exhibited.

The first void P1 and the second void P2 may have substantially the same size. Since the first void P1 is located at the edge of the protrusion pattern 230 and does not have a complete circular or elliptical shape, the size (eg, diameter, particle size) of the first void P1 is determined by the first void P1 . ) may be understood as a size corresponding to twice the radius of curvature of the arc formed, but the present invention is not limited thereto. If the first void P1 and the second void P2 have an elliptical or distorted shape rather than a perfect circle shape, the size of the void is the diameter of an imaginary circle corresponding to the area of the void in the shape of an ellipse, that is, equivalent diameter.

The size of the pores P, that is, the distribution range of the diameter and the average diameter may both affect the polishing rate, but in particular, the average diameter may be a very important factor. As described above, the arrangement density or density of the pores P may also affect the edge shape and durability of the protrusion pattern 230 , but may also affect the average diameter of the pores P.

In an exemplary embodiment, the average diameter of the pores P is about 10 μm to 150 μm, or about 20 μm to 150 μm, or about 30 μm to 130 μm, or about 50 μm to 110 μm, or about 60 μm to 100 μm.

When the average diameter of the pores P is too large, for example, the plurality of first pores P1 are not located on any one side forming the minimum width of the protrusion pattern 230 but one on any one side. Only three to three levels of the first voids P1 may be located, or even the size of the first voids P1 may be greater than the length of any one side of the protrusion pattern 230 . In this case, it is difficult to exhibit an effect of substantially increasing the circumferential length, and a reduction in the polishing area of the protruding pattern 230 may be caused. Also, the difference between the area excluding only the area of the first voids P1 from the upper area of the protruding pattern 230 and the area excluding the entire area of the voids P from the upper area of the protruding pattern 230 increases, It may not show the designed polishing rate.

On the other hand, when the average diameter of the pores P is too fine, the durability of the protrusion pattern 230 may be deteriorated due to the first pore P1 positioned at the edge of the protrusion pattern 230 , and a polishing defect may occur.

Despite the difference in the average diameter of the pores P, the arrangement density and distribution of the pores, such as the area occupied by the pores P, may be configured as described above to improve the intended polishing properties.

Although the present invention is not limited thereto, the diameter distribution of the pores P including the first pores P1 and the second pores P2 is about 1 μm to 500 μm, or about 5 μm to 400 μm, or It may be in the range of about 80 μm to 300 μm.

In some embodiments, a side surface of the protrusion pattern 230 may have a third void P3 . That is, the third void P3 refers to a void exposed only on the side surface of the protrusion pattern 230 , not on the top surface. At least some of the plurality of pores included in the protrusion pattern 230 may be exposed to a side surface of the protrusion pattern 230 to form a recessed groove.

The groove of the side surface of the protruding pattern 230, that is, the third void P3, is not exposed to the upper surface of the protruding pattern 230, that is, the polishing surface, and the first void ( It has a difference from P1) and the second void P2.

A predetermined separation distance may be provided between the protruding patterns 230 adjacent to each other. The polishing liquid, that is, the slurry 70, flows through the separation space and may affect polishing properties. If the slurry flow path between the protrusion patterns 230 is too small, a problem such as partial agglomeration of the slurry 70 may occur. There is a limit to controlling the separation distance between the protrusion patterns 230 having a predetermined shape, and this may cause a reduction in the area of the upper portion of the protrusion patterns 230 .

The side surface of the protrusion pattern 230 according to the present embodiment has a predetermined groove formed by the third cavity P3, and the groove may be used to contribute to an increase in the flow of the slurry 70 . Since the size of the third void P3 and the like have been described together with the first void P1 and the second void P2 , the overlapping description will be omitted. For example, the average diameter of the third pores P3 may be in the range of about 20 μm to 150 μm, or about 30 μm to 130 μm, or about 50 μm to 110 μm, or about 60 μm to 100 μm.

Meanwhile, although the present invention is not limited thereto, when the polishing process is performed using the polishing pad 11 according to the present embodiment, the protrusion pattern 230 is cut from the upper end and the height H of the protrusion pattern 230 gradually increases. can be lowered At this time, the height of the protrusion pattern 230 is lowered, the third void P3 is exposed, and may be changed to the above-described first void P1 .

As described above, the first void P1 and the second void P2 contribute to an increase in the peripheral length of the edge of a certain protrusion pattern 230 , and may also affect the polishing area formed by the protruding pattern 230 . have. In addition, the third pore P3 may be exposed on the side surface of the protrusion pattern 230 to affect the flow of the slurry 70 .

In manufacturing the polishing pad 11 , for example, when the circumferential length of the protruding pattern 230 is controlled after determining the polishing area in design, the size of the protruding pattern 230 is very limited. In addition, when the protrusion pattern 230 is formed in detail in order to secure a sufficient circumferential length, it causes an increase in manufacturing cost.

However, as in the present embodiment, when the protrusion pattern 230 forms pores, a perimeter length greater than the calculated perimeter may be formed. Therefore, even if the manufacturing cost is increased as in the prior art, when the protrusion pattern 230 is formed in detail, a larger increase in the circumferential length can be achieved. For example, the circumferential length of the protruding pattern 230 of the actually manufactured polishing pad 11 may be greater than the initially determined circumferential length per unit area. On the other hand, even if a larger protrusion pattern 230 is formed than in the prior art, that is, even if the manufacturing cost is reduced, there is an advantage in that the perimeter length of the conventional level can be secured.

Hereinafter, the trench 300 of the polishing pad 11 will be described. One surface of the polishing pad 11 , for example, the upper surface of FIG. 6 may have a trench 300 . The trench 300 may perform a channel function for transporting and discharging the slurry 70 dropped on the upper surface of the polishing pad 11 . If necessary, the term 'trench' used herein may be used interchangeably with terms such as a channel, a groove, and a groove.

The trench 300 may include a first trench 310 having a linear shape extending in the first direction (X), the second direction (Y), and/or diagonally. The first trench 310 may have a shape extending in a radial direction from the center of the circular polishing pad 11 . FIG. 2 illustrates a case in which eight first trenches 310 inclined in the first direction (X), the second direction (Y), and 45 degree directions are formed. Accordingly, the polishing pad 11 may be divided into eight sectoral regions having a central angle of approximately 45 degrees. At least a portion of the first trenches 310 of the polishing pad 11 according to the present embodiment may be extended in the arrangement direction of the protrusion patterns 230 , that is, in the first direction (X) and the second direction (Y). have. However, the present invention is not limited thereto.

The first trench 310 may induce the slurry 70 to move or flow in the radial outer direction of the polishing pad 11 due to centrifugal force generated according to the rotation of the polishing pad 11 . Through this, even when the nozzle 60 does not move and the slurry 70 is dripped, the slurry 70 can be applied to the entire surface of the polishing pad 11, and excessive aggregation is prevented in a part. It is possible to improve the utilization efficiency of the slurry. In some embodiments, the first trench 310 may be configured to increase in depth toward the outer direction.

In addition, the trench 300 may further include a second trench 320 arranged in a concentric circle with respect to the center of the circular polishing pad 11 . 2 illustrates a case in which there are three second trenches 320, of course, the present invention is not limited thereto. Any second trench 320 may be provided to intersect the plurality of first trenches 310 . The second trench 320 may induce the slurry 70 to move or flow in the rotational direction of the polishing pad 11 , ie, the circumferential direction, due to centrifugal force generated according to the rotation of the polishing pad 11 .

Although the present invention is not limited thereto, preferentially, the slurry 70 flowing in the outer direction of the polishing pad 11 through the first trench 310 rotates the polishing pad 11 by the second trench 320 . direction can flow. Accordingly, forming the maximum width of the first trench 310 larger than the maximum width of the second trench 320 may be advantageous in terms of preventing agglomeration of the slurry 70 .

6 illustrates a case in which the first trench 310 (and the second trench) has a depth substantially equal to the thickness T2 of the base 210 . Accordingly, the upper surface of the support layer 100 may be partially exposed through the trench 300 . However, the present invention is not limited thereto, and in another embodiment, the depth of the trench 300 is smaller than the thickness of the base 210 , and thus the support layer 100 may not be exposed. In another embodiment, the depth of the trench 300 is greater than the thickness of the base 210 , and accordingly, the support layer 100 may also have a shape partially having the trench.

In addition, in the present embodiment, the first trench 310 and the second trench 320 impart a predetermined fluidity to each pattern layer 200 , and the protruding pattern 230 of the polishing pad 11 as described above. It can be made to follow along the curvature of this polishing object substrate 50. As shown in FIG.

That is, the upper surface of the support layer 100 may be partially exposed by the first trench 310 and the second trench 320 , and the pattern layer 200 may be spaced apart from each other based on the first trench 310 . have. That is, the base 210 that is partitioned based on the first trench 310 and the like may be disposed on one support layer 100 . Accordingly, it is possible to have fluidity in the plane direction by the pressure in the third direction (Z) applied to the pattern layer 200 , and to make vertical tracking along the curved surface of the substrate 50 to be polished more flexible. can

To this end, in some embodiments, the maximum depth of the trench 300 , for example, the maximum depth of the first trench 310 may be greater than the height H of the protrusion pattern 230 . In the exemplary embodiment in which the trench 300 is formed in the pattern layer 200 , the maximum depth of the first trench 310 is greater than the height of the protruding pattern 230 is the flowability of the pattern layer 200 and the substrate to be polished. It can be advantageous in terms of following.

Hereinafter, follow characteristics and polishing characteristics of the polishing pad 11 according to the present embodiment will be described with further reference to FIGS. 7 to 10 .

7 is an exemplary schematic diagram illustrating a state in which the polishing pad 11 is in contact with the substrate 50 to be polished, and FIG. 8 is a state in which the polishing pad polished by a conventional conditioner is in contact with the substrate 50 to be polished. It is an exemplary schematic diagram shown.

First, referring to FIG. 7 , when the lower surface of the substrate 50 to be polished has a fine curve, the polishing pad 11 according to the present embodiment has sufficient flexibility in the vertical direction, for example, gravity, as the support layer 100 has sufficient flexibility. Elastic deformation in the direction may be possible. Through this, the upper surface of the protruding pattern 230 forming the polishing surface can be in close contact with the curved surface of the polishing target substrate 50 , and the slurry is evenly distributed between the pattern layer 200 and the polishing target substrate 50 , and excellent polishing rate can be achieved.

In addition, the portion in which the polishing target substrate 50 convexly protruding to the lower side is in contact with the polishing pad 11 is where the polishing target substrate 50 concavely indented relatively upward is in contact with the polishing pad 11 . A relatively greater pressure can be applied compared to the part, thereby minimizing the polishing non-uniformity (NU) and achieving uniform polishing.

In particular, the polishing pad 11 according to the present embodiment forms the rigidity of the pattern layer 200 greater than that of the support layer 100 , so that when the polishing pad 11 is pressed against the substrate 50 to be polished, the pattern layer 200 . ), the deformation degree of the support layer 100 may be greater than that of the protrusion pattern 230 and the base 210 . As a non-limiting example, the pattern layer 200 may be configured such that only the support layer 100 is flexibly deformed while causing substantially no deformation or minimal deformation. If the protrusion pattern 230 has excessive flexibility and is easily deformed by vertical pressure, the polishing area of the protrusion pattern 230 is deformed, and the intended polishing rate is not exhibited due to shape deformation such as inclination in the horizontal direction. may not be

Therefore, the support layer 100, not the pattern layer 200, is deformed to follow the curve of the surface of the substrate 50 to be polished, and at the same time, an excellent polishing rate can be exhibited. Although the present invention is not limited thereto, as a non-limiting example, the maximum rate of change in the plane direction with respect to the vertical pressure of the pattern layer 200 including the protruding pattern 230 , or the material constituting the pattern layer 200 . The material may be selected so that it is about 20.0% or less, or about 15.0% or less, or about 10.0% or less, or about 5.0% or less.

On the other hand, referring further to FIG. 8 , in the case of the conventional polishing pad 11 ′, uniform roughness is exhibited over the entire surface of the polishing pad 11 ′ despite the surface roughness being maintained by a conditioner (not shown). It is substantially difficult to clean, and thus, it is impossible to adhere to the polishing target substrate 50 having a curved surface, thereby increasing polishing non-uniformity and even causing scratch defects.

9 is another exemplary schematic view showing a state in which the polishing pad 11 is in contact with the substrate 50 to be polished, and FIG. 10 is a state in which the polishing pad polished by a conventional conditioner is in contact with the substrate 50 to be polished. It is an exemplary schematic diagram showing. 9 and 10 illustrate a case in which the polishing target substrate 50 includes a device pattern 50b disposed on a base substrate 50a and an overcoat layer 50c thereon. The device pattern 50b may be a wiring pattern made of metal or an active pattern including a semiconductor material, but is not particularly limited.

First, referring to FIG. 9 , when the overcoating layer 50c having a very fine degree of curvature or step is located on the lower surface of the substrate 50 to be polished, the polishing pad 11 according to the present embodiment is The top of the pattern layer 200 may have a uniform height and the overcoat layer 50c may be uniformly planarized. That is, by selectively polishing only the overcoat layer 50c protruding convexly to the lower side, and minimizing physical pressure on the overcoat layer 50c concave in the upper side relatively, damage to the element of the substrate 50 to be polished Global planarization can be achieved without Therefore, the polishing pad 11 according to the present embodiment may be applicable to the STI structure process or the like. This will be described later along with experimental examples.

On the other hand, referring further to FIG. 10 , in the case of the conventional polishing pad 11 ′, it is practically difficult to exhibit uniform roughness over the entire surface, and in some cases, it is polished up to the overcoat layer 50c that is relatively concavely indented upward. can be done Accordingly, the device of the polishing target substrate 50 may be damaged or only a degree of partial planarization may be achieved, so it is not suitable for use in a precision planarization process.

Hereinafter, other embodiments of the present invention will be described. However, a description of a configuration identical to or extremely similar to that of the polishing pad 11 according to the above-described embodiment will be omitted, which can be clearly understood by those skilled in the art from the description of the accompanying drawings and detailed description. will be. It goes without saying that a polishing apparatus to which a polishing pad according to other embodiments is applied can be easily conceived.

11 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 11 , the protrusion pattern 232 of the pattern layer 202 of the polishing pad 12 according to the present embodiment has an approximately '+' shape rather than a rectangular shape in a plan view, as shown in FIG. 4 and the like. It is different from the polishing pad according to the example.

The plurality of protrusion patterns 232 may be disposed on the base 210 . As described above, the protrusion patterns 232 may be repeatedly arranged along at least two directions to form an approximately regular arrangement. For example, the protrusion patterns 232 may be repeatedly arranged with the same spacing in the first direction (X) and the second direction (Y). Although not shown in the drawings, at least some of the first trenches (not shown) extending in the radial direction may be substantially parallel to the arrangement direction of the protrusion patterns 232 , but the present invention is not limited thereto.

The protrusion pattern 232 may have an approximately '+' shape. Specifically, the extension portions 232p may be extended in the same first direction (X) and second direction (Y) as the arrangement direction based on an arbitrary point. Accordingly, the protrusion pattern 232 may have four indentations 232v in the upper left portion, the upper right portion, the lower right portion, and the lower left portion in a plan view.

In this case, the maximum width Wmax of the protrusion pattern 232 may be expressed as the length of the two extension portions 232p extending in substantially opposite directions. On the other hand, the minimum width Wmin of the protrusion pattern 232 may be expressed as a width of a certain extension portion 232p.

As described above, a certain protrusion pattern 232 has a first void P1 and a second void P2 contributing to an increase in the circumferential length. In addition, although not shown in the drawings, the protrusion pattern 232 may have a third void (not shown) located on the side surface.

The size of the protrusion pattern 232 may affect the polishing rate of the polishing pad 12 , the polishing non-uniformity, and the like. In the case of the protrusion pattern 232 having a substantially regular cross shape as in the present embodiment, the perimeter length per unit area of the protrusion pattern 232 may be substantially the same as in the embodiment of FIG. 4 . On the other hand, a polishing area different from that of FIG. 4 may be provided, and a degree of freedom in design may be secured by using the shape of the protrusion pattern 232 as in the present embodiment.

In addition, when a certain protrusion pattern 232 has the indentation 232v as in the present embodiment, the slurry (not shown) flowing on the upper surface of the polishing pad 12 rides on the upper surface of the protruding pattern 232 in the opposite direction. can form a flowing structure. That is, the flow of the slurry is trapped and/or controlled by the indentation of the protruding pattern 232 as well as the upper surface of the base 210, so that it can be configured to forcibly flow to the upper surface of the protruding pattern 232, Through this, it is possible to increase the utilization efficiency of the slurry.

12 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 12 , the protrusion pattern 233 of the pattern layer 203 of the polishing pad 13 according to the present embodiment has an approximately pivoted '+' shape in a plan view according to the embodiment of FIG. 11 . It is different from a polishing pad. That is, the protrusion pattern 233 may have an approximately 'X' shape in a plan view. In this specification, the '+' shape and the 'X' shape may be regarded as the same shape except for the pivoted point.

As described above, a certain protrusion pattern 233 has a first void P1 and a second void P2 contributing to an increase in the circumferential length. In addition, although not shown in the drawings, the protrusion pattern 233 may have a third void (not shown) located on the side surface.

The protrusion pattern 233 has extension parts 233p extending based on an arbitrary point, and the extending direction of the extension part 233p is the arranging direction of the protrusion patterns 233 , that is, It may be a direction crossing the first direction (X) and the second direction (Y). In addition, the maximum width Wmax of the protrusion pattern 233 is expressed as the sum of the lengths of the two extension portions 233p, and the minimum width Wmin is expressed as the width of a certain extension portion 233p as described above. A circumferential length and a planar area per unit area of the protrusion pattern 233 according to the present exemplary embodiment may be substantially the same as those of the exemplary embodiment of FIG. 11 .

When the protrusion pattern 233 is pivoted on a plane as in the present embodiment, the indentation portion 233v is positioned on one side and the other side of the protrusion pattern 233 in the first direction (X) and on one side and the other side in the second direction (Y). can make it Although the present invention is not limited thereto, the slurry may have a large tendency to move in a radial direction due to centrifugal force generated by rotation of the polishing pad 13 . In addition, the radial direction at a certain position may substantially coincide with the first direction (X). Accordingly, when the indentations 233v are arranged as in the present embodiment, the flow structure of the slurry can be strengthened, and the polishing efficiency can be improved.

13 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 13 , the point that the plurality of protruding patterns 234 of the pattern layer 204 of the polishing pad 14 according to the present embodiment together form a protruding pattern group 234N is the polishing according to the embodiment of FIG. 12 . It is different from the pad.

Any one of the protrusion patterns 234 may have the same shape as in the embodiment of FIG. 4 and the like. On the other hand, the plurality of protrusion patterns 234 may be adjacent to each other to form a protrusion pattern group 234N. The plurality of protrusion pattern clusters 234N may be regularly arranged in the first direction (X) and the second direction (Y).

Any one protrusion pattern group 234N includes a plurality of protrusion patterns 234 , and the plurality of protrusion patterns 234 may be approximately regularly arranged in any one protrusion pattern group 234N. 13 illustrates a case in which one protrusion pattern group 234N includes five protrusion patterns 234 .

As described above, any protrusion pattern 234 means a unit structure having a shape independent of each other, and even when the protrusion pattern clusters 234N are regularly arranged, the terms minimum width, maximum width, etc. used herein are any one It should be understood as referring to the protrusion pattern 234 of

The protrusion pattern cluster 234N may have an approximately 'X' shape as a whole. Any one protrusion pattern group 234N may have a recess 234v formed by adjacent protrusion patterns 234 . The protrusion patterns 234 may be in a diagonally abutting state, but the present invention is not limited thereto.

Each of the protrusion patterns 234 may have a first void P1 and a second void P2 that contribute to an increase in the circumferential length. In addition, although not shown in the drawings, each of the protrusion patterns 234 may have third voids (not shown) located on the side surfaces.

In this embodiment, the maximum width Wmax of the protrusion pattern 234 is expressed as a length in the diagonal direction of the protrusion pattern 234 having a substantially rectangular shape, and the minimum width Wmin of the protrusion pattern 234 is one side of the protrusion pattern 234 . It can be expressed as a length.

In this embodiment, in providing the protruding pattern group 234N having the overall shape as shown in FIG. 12, one protruding pattern group 234N is composed of a plurality of protruding patterns 234 to increase the perimeter length. have. In this case, a polishing area substantially the same as or similar to that of the embodiment of FIG. 12 is provided, but the perimeter length per unit area may be further increased. In this way, design freedom can be secured.

14 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 14 , the protrusion pattern 235 of the pattern layer 205 of the polishing pad 15 according to the present embodiment includes a first protrusion pattern 235a and a second protrusion pattern 235b having different shapes. This is different from the polishing pad according to the embodiment of FIG. 13 .

The first protrusion pattern 235a is located at an approximate center of the protrusion pattern group 235N, and may have substantially the same shape as the protrusion pattern according to the exemplary embodiment of FIG. 4 . On the other hand, the second protrusion pattern 235b is arranged to surround the first protrusion pattern 235a and may have an approximately 'X' shape.

The plurality of protrusion pattern clusters 235N may be regularly arranged along the first direction X and the second direction Y. 14 illustrates a case in which one protrusion pattern group 235N includes one first protrusion pattern 235a and four second protrusion patterns 235b. The protrusion pattern cluster 235N may have an approximately 'X' shape as a whole. Any one protrusion pattern group 235N may have a recess 235v formed by one adjacent first protrusion pattern 235a and two second protrusion patterns 235b. Any of the second protruding patterns 235b and the first protruding patterns 235a may be in a state in which they contact each other in a diagonal direction, but the present invention is not limited thereto.

Any one of the second protrusion patterns 235b may include four extension parts 235p extending from a certain point. As the second protrusion pattern 235b has an approximately 'X' shape, each of the second protrusion patterns 235b may also form a detailed indentation. The detailed indentation allows the flowing slurry to flow along the upper surface of the protrusion pattern 235 in the opposite direction, thereby further improving the use efficiency of the slurry.

Each of the first protrusion pattern 235a and the second protrusion pattern 235b may have a first void P1 and a second void P2 that contribute to an increase in circumferential length. Also, although not shown in the drawings, the first protrusion pattern 235a and the second protrusion pattern 235b may each have third voids (not shown) positioned on the side surfaces.

In the present embodiment, the maximum width Wmax-a of the first protrusion pattern 235a may be expressed as a diagonal length of a substantially rectangular pattern, and the minimum width Wmin-a may be expressed as a length of one side. On the other hand, the maximum width Wmax-b of the second protrusion pattern 235b is expressed as the sum of the extension lengths of the two extension portions 235p extending in opposite directions, and the minimum width Wmin-b is the extension portion 235p. ) can be expressed as the width of

According to the present embodiment, while providing a smaller polishing area compared to the polishing pad of FIG. 13 , it is possible to provide a larger peripheral length per unit area than the polishing pad of FIG. 13 . In this way, design freedom can be secured.

15 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 15 , at least a portion of the protrusion pattern 236 of the pattern layer 206 of the polishing pad 16 according to the present embodiment has an approximately 'X' shape, and at least another part has a '+' shape. The point is different from the polishing pad according to the embodiment of FIG. 14 . Accordingly, the protrusion patterns 236 in any one protrusion pattern group 236N may be spaced apart from each other. When a plurality of protrusion patterns 236 are spaced apart from each other within a certain protrusion pattern group 236N, a path through which large particles or impurities in the slurry pass may be provided. That is, the particles that cause damage to the substrate to be polished do not flow to the upper surface of the protrusion pattern 236 but pass through the separation space, thereby further improving the polishing properties.

The protrusion pattern clusters 236N may be regularly arranged in the first direction (X) and the second direction (Y). The protrusion pattern cluster 236N may have an approximately 'X' shape as a whole. Any one protrusion pattern group 236N may have a recess 236v formed by adjacent protrusion patterns 236 .

Any one protrusion pattern 236 may have a plurality of extension parts 236v.

Meanwhile, each of the protrusion patterns 236 may have a first void P1 and a second void P2 that contribute to an increase in the circumferential length. In addition, although not shown in the drawings, each of the protrusion patterns 236 may have third voids (not shown) located on the side surfaces.

In the present embodiment, the minimum width Wmin of the protrusion pattern 236 may be expressed as the width of any extension portion 236p.

16 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 16 , the protrusion pattern group 237N of the pattern layer 207 of the polishing pad 17 according to the present embodiment is composed of nine protrusion patterns 237 which is the same as the polishing pad according to the embodiment of FIG. 15 . that is different. In the present embodiment, the minimum width Wmin of the protrusion pattern 237 may be expressed as the width of one extension 237p of any protrusion pattern 237 .

The protrusion pattern 237 according to the present embodiment has a shape substantially similar to that of FIG. 15 , but may be provided to provide a larger circumferential length.

17 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 17 , the arrangement direction of the plurality of protrusion pattern groups 238N of the pattern layer 208 of the polishing pad 18 according to the present embodiment, and the protrusion patterns 238 in a certain protrusion pattern group 238N The different arrangement directions are different from the polishing pad according to the embodiment of FIG. 16 .

That is, the plurality of protrusion pattern clusters 238N may be arranged in the first direction X and the second direction Y. Each protrusion pattern 238 may be arranged in a direction crossing the first direction (X) and the second direction (Y). More specifically, the protrusion pattern cluster 238N may have an overall pivoted shape.

According to the present embodiment, the arrangement density of the protrusion pattern 238 or the protrusion pattern group 238N may be increased, and the polishing area per unit area or the perimeter length per unit area may be controlled. For example, compared to the case where the arrangement direction of the protrusion pattern clusters and the extension direction of each protrusion pattern cluster, that is, the arrangement direction of the unit protrusion patterns are the same as shown in FIG. can be higher

18 is a plan view illustrating an arrangement of protruding patterns of a polishing pad of a polishing apparatus according to another embodiment of the present invention.

Referring to FIG. 18 , the arrangement direction of the protruding pattern clusters 239 of the pattern layer 209 of the polishing pad 19 according to the present embodiment intersects the first direction (X) and the second direction (Y). The point is different from the polishing pad according to the embodiment of FIG. 17 .

As described above, the first direction X and the second direction Y may be substantially parallel to a direction in which some of the first trenches (not shown) extending in the radial direction extend. That is, in the polishing pad 19 according to the present embodiment, the arrangement direction of the protrusion pattern groups 239N and the arrangement direction of the protrusion patterns 239 in any one protrusion pattern group 239N are the extension directions of the first trenches. and may be in a different direction.

18 illustrates a case in which the arrangement direction of the protrusion pattern clusters 239N and the arrangement direction of the protrusion patterns 239 are substantially the same, however, in another embodiment, both directions may cross each other.

Hereinafter, the present invention will be described in more detail with reference to specific preparation examples, comparative examples and experimental examples.

Preparation Example 1: Preparation of a polishing pad having a protruding pattern

A protrusion pattern having the same shape as in FIG. 18 was formed. In this case, the area occupied by the protrusion pattern was made to be about 10.0% of the total area. The minimum width of the protrusion pattern was about 20 μm. The formation method of the protrusion pattern used laser processing. In addition, the pattern layer had porosity, and the average particle size of the pores was 10 μm and the volume ratio was about 25%.

In addition, various polishing pads were prepared by adjusting the pattern size to control the perimeter length.

Preparation Example 2: Preparation of a polishing pad having a protruding pattern

A polishing pad having the same shape as in Preparation Example 1 was manufactured, except that the minimum width of the protrusion pattern was formed to be about 60 μm. In addition, various polishing pads were prepared by adjusting the pattern size to control the perimeter length.

Preparation Example 3: Preparation of a polishing pad having a protruding pattern

A polishing pad having the same shape as in Preparation Example 2 was prepared, except that the pores had an average particle size of 20 μm and a volume ratio of about 40%. In addition, various polishing pads were prepared by adjusting the pattern size to control the perimeter length.

Preparation Example 4: Preparation of a polishing pad having a protruding pattern

A polishing pad having the same shape as in Preparation Example 2 was prepared except that the pores had an average particle size of 40 μm and a volume ratio of about 40%. In addition, various polishing pads were prepared by adjusting the pattern size to control the perimeter length.

Preparation Example 5: Preparation of a polishing pad having a protruding pattern

A polishing pad having the same shape as in Preparation Example 2 was prepared, except that the pores having an average particle size of 100 μm and a volume ratio of about 30% were used.

Preparation Example 6: Preparation of a polishing pad having a protruding pattern

A polishing pad having the same shape as in Preparation Example 2 was prepared, except that the pores having an average particle size of 200 μm and a volume ratio of about 20% were used.

Experimental Example 1: Polishing rate according to perimeter length per unit area

The effect of the perimeter length per unit area on the polishing rate characteristics was confirmed using the polishing pads according to Preparation Examples 1 to 4. ^{About 1mm/mm 2} , about 2mm/mm ² , about 3mm/mm ² , about 4mm/mm ² , about 5mm/mm ² , about 6mm by adjusting the size of the pattern while maintaining about 10% of the polishing area /mm ² , about 7mm/mm ² , about 8mm/mm ² , about 10mm/mm ² , about 15mm/mm ² , about 25mm/mm ² Various polishing pads having a peripheral length were prepared. At this time, the minimum width and pore conditions of the pattern maintained the conditions presented in Preparation Examples 1 to 4.

For the polishing experiment, an 8-inch oxide wafer and TSO-12 (Soulbrain), a slurry for oxide, were used. The apparent contact pressure was 150 g/cm ² . The apparent contact pressure (Pa) may be defined as a value obtained by dividing the total load applied to the substrate to be polished by the carrier by the area of the substrate to be polished. The rotation speed of the polishing pad was fixed at 61 rpm.

And the results are shown in FIG. 19 . Referring to FIG. 19 , it can be seen that the polishing rate increases as the perimeter length per unit area of the protruding pattern increases. However, it can be seen that the increase in the polishing rate is not linear, but gradually decreases and slows down as the circumferential length increases, and converges to a predetermined value. For example, it is expected that the polishing efficiency will converge within about 50 mm/mm ^{2 .}

Through this, it was confirmed that the polishing rate could be controlled according to the area ratio and the perimeter length.

In particular, comparing Preparation Examples 2 to 4, in which the minimum width of the protrusion pattern is about 60 μm, it can be seen that the polishing rate gradually increases even when the circumferential length is the same as the average particle size of the pores increases. Comparing Preparation Example 1 with Preparation Examples 3 and 4, it can be seen that Preparation Examples 3 and 4 exhibit a higher polishing rate than Preparation Example 1 having a smaller minimum width of the protrusion pattern.

Experimental Example 2: Polishing rate according to voids

Using the polishing pads according to Preparation Examples 1 to 5, the effect of the average size of the pores on the characteristics on the polishing rate was confirmed. The circumferential length of the polishing pad was fixed to ^{15 mm/mm 2 .} As a comparative example, an IC1010 pad manufactured by Dow, a commercial polishing pad, was used.

The polishing conditions were with a, the polishing pressure and the rotational speed of the pad in one of 61rpm, 93rpm one of 150g / cm ² and 300g / cm ² was expressed by the product of the horizontal axis represents the rotation speed and pressure. And the results are shown in FIGS. 20 and 21 .

Referring to FIGS. 20 and 21 , when the protrusion pattern has the same minimum width, it can be seen that the polishing rate increases as the size of the pores increases. In particular, comparing Preparation Example 1 and Preparation Example 3, Preparation Example 3 exhibited a high level of polishing rate despite having a larger minimum width. On the other hand, it was confirmed that the polishing efficiency of the polishing pads according to Preparation Examples 3 to 5 of the present invention was further increased as the polishing conditions of the higher level, that is, the polishing rate and the polishing pressure were increased.

In the case of Preparation Example 6 in which the average particle size of the pores was 200 μm, the pattern shape was collapsed due to the pores, and it was difficult to maintain the polishing area at 10%. In addition, in the case of Preparation Example 6, the measured polishing rate was low, and damage to the polishing substrate was observed, so that it could be determined that polishing was not performed.

In the above, the embodiment of the present invention has been mainly described, but this is only an example and does not limit the present invention. It will be appreciated that various modifications and applications not exemplified above are possible.

Therefore, it should be understood that the scope of the present invention includes changes, equivalents or substitutes of the technical ideas exemplified above. For example, each component specifically shown in the embodiment of the present invention may be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

1: Polishing device
10: abrasive platen
11: polishing pad
40: carrier
50: substrate to be polished
60: nozzle
70: slurry
100: support layer
200: pattern layer
210: base
230: pattern layer
300: trench

Claims (15)

support layer; and
A pattern layer disposed directly on the support layer, including a pattern layer including a protruding pattern having a plurality of pores,
The voids contribute to an increase in the perimeter length on a plane of the protrusion pattern, and the perimeter length of the polishing surface formed by the protrusion pattern per unit area is in the range of ^{1.0 mm/mm 2} to 50.0 mm/mm ^{2 .} According to claim 1,
A polishing pad having a rigidity of the pattern layer greater than a rigidity of the support layer. According to claim 1,
In a planar view, the ratio of the area occupied by the voids to the total area of the upper surface of any one protrusion pattern is 10% to 50%. 2. The method of claim 1
The perimeter length of any one protrusion pattern is 4 to 50 times the minimum width of the any protrusion pattern. 2. The method of claim 1
A polishing pad in which the circumferential length of the polishing surface formed by the protruding pattern per unit area is in the range of 0.1 to 1.0 times the reciprocal of the minimum width of a certain protruding pattern. 2. The method of claim 1
The circumferential length of any protruding pattern is 1.5 times to 3.5 times greater than the circumferential length when the first void is not present. 2. The method of claim 1
The minimum width of the protrusion pattern is 20㎛ or more,
The average diameter of the pores is in the range of 10㎛ to 150㎛ polishing pad. 2. The method of claim 1
In a planar view, the area occupied by the voids per unit area is 0.5% to 20% of the polishing pad. 9. The method of claim 8
In a planar view, the actual polishing area of the protruding pattern per unit area is 5% to 30% of the polishing pad. 2. The method of claim 1
The pores are located on the side surface of the protrusion pattern to form a side groove of the protrusion pattern, and include a third cavity that contributes to an increase in the side area and affects the flow of the slurry during the polishing process, wherein the average of the third pores A polishing pad having a diameter in the range of 20 μm to 150 μm. 2. The method of claim 1
The porosity of the support layer is different from the porosity of the pattern layer. an abrasive platen configured to rotate; and
A polishing apparatus comprising the polishing pad according to claim 1 disposed on the polishing platen. determining a contact pressure required for polishing and a planar shape and length component of the protruding pattern;
determining a polishing area of the protruding pattern in contact with the polishing target substrate in consideration of the contact pressure;
determining a circumferential length per unit area of the protrusion pattern in consideration of the contact pressure and the determined polishing area; and
Method of manufacturing a polishing pad comprising the step of manufacturing a pattern layer including the protrusion pattern. 14. The method of claim 13,
The pattern layer includes a protruding pattern having a plurality of pores, and the pores contribute to an increase in the perimeter of the protruding pattern,
In the manufacturing of the pattern layer, the length element of the manufactured protrusion pattern is larger than the determined length element. 14. The method of claim 13,
Before the step of manufacturing the pattern layer, the method of manufacturing a polishing pad further comprising the step of determining the size of the voids contained in the protrusion pattern.

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