KR20220009877A - Chemical-mechanical polishing pad including porous protruding pattern and method for preparing the same using laser - Google Patents

Abstract

Provided are a chemical-mechanical polishing pad which improves a polishing rate, and at the same time, reduces manufacturing cost by having porous protruding patterns, and a manufacturing method using laser. The polishing pad comprises: a support layer; and a pattern layer disposed on the support layer and having protruding patterns having a plurality of pores. The protruding pattern has the pore exposed to a side surface, and a ratio of the sum of height occupied by side pores with respect to vertical height of the protruding pattern is disposed in a range of 10-50%.

Description

Chemical-mechanical polishing pad including porous protrusion pattern and manufacturing method thereof using laser

The present invention relates to a polishing pad including a protruding pattern formed on a polishing surface and a method for manufacturing the same. Specifically, it relates to a chemical-mechanical polishing pad capable of reducing manufacturing cost while improving a polishing rate by including a porous protrusion pattern and a manufacturing method using a laser.

In general, a chemical-mechanical polishing (CMP) process is used to manufacture high-integration circuit devices such as semiconductors and displays. 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 above a certain level, and the polishing apparatus including the polishing pad maintains 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 a semiconductor, 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 to be solved by the present invention is to provide a method capable of manufacturing a polishing pad including a porous protruding pattern having porosity in a more convenient way.

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 on the support layer, including a pattern layer including a protruding pattern having a plurality of pores, wherein the protruding pattern has pores exposed on the side surface, and the side pores with respect to the vertical height of the protrusion pattern The proportion of the sum of the heights they occupy is in the range of 10% to 50%.

The average diameter of the pores may be in the range of 20% to 40% of the vertical height of the protrusion pattern.

In addition, the pattern layer includes a base and the plurality of protrusion patterns disposed on the base, and the value obtained by subtracting the surface skewness (Rsk_pattern) of the protrusion pattern surface from the surface skewness (Rsk_base) of the upper surface of the base is less than 0 can be large

The pattern layer may include a base and the plurality of protrusion patterns disposed on the base, and the arrangement density of pores on the upper surface of the base may be smaller than the arrangement density of pores on the surface of the protrusion pattern.

The pattern layer may include a base and the plurality of protrusion patterns disposed on the base, and the base may have at least a partially recessed first trench.

In addition, the base may have pores exposed on the inner wall of the first trench, and the average diameter of the pores exposed on the inner wall of the first trench may be in the range of 30 μm to 150 μm.

In addition, the first trench may pass through the base, and an upper surface of the support layer may be at least partially exposed by the first trench.

The support layer is a second trench that is at least partially recessed, and may have a second trench connected to the first trench.

The base has pores exposed on the inner wall of the first trench, and the support layer has pores exposed on the inner wall of the second trench, wherein the average diameter of the pores of the inner wall of the second trench is , may be larger than the average diameter of pores of the inner wall of the first trench.

In addition, the first trench includes a plurality of radiation trenches extending radially from the center of the circular polishing pad, and concentric trenches having a concentric shape with respect to the center and connecting the plurality of radiation trenches, the width of the radiation trenches may be greater than the width of the concentric trench.

The first trench may not penetrate the base, and a surface roughness of a bottom surface of the first trench may be smaller than a surface roughness of an inner wall of the first trench.

A polishing pad according to another 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 method of manufacturing a polishing pad according to an embodiment of the present invention for solving the above other problems includes preparing a pattern layer having porosity; and partially removing the pattern layer using a laser, comprising: forming a base and a plurality of protruding patterns disposed on the base; removing it.

The partially removing the pattern layer may include forming a trench in the base, and may further include forming the trench to have pores exposed on an inner wall of the first trench.

Also, the partially removing the pattern layer may include forming a trench in the base, and may further include forming a trench penetrating the base.

In some embodiments, disposing the patterned layer on a support layer; and at least partially removing the support layer through a trench through the base.

A method of manufacturing a polishing pad according to another embodiment of the present invention for solving the above other problems 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.

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

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 substrate to be polished, 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 planar layout of a polishing pad according to another embodiment of the present invention.
12 is an enlarged perspective view showing an enlarged portion A of FIG. 11 .
13 is a cross-sectional view taken along line BB′ of FIG. 12 .
14 to 18 are cross-sectional views of a polishing pad according to still other embodiments of the present invention, respectively.
19 to 22 are views sequentially illustrating a method of manufacturing a polishing pad according to an embodiment of the present invention.

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 that intersects or is perpendicular to 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

In the present specification, surface roughness defined as skewness or surface skewness may mean a characteristic value indicating the direction and degree of asymmetry with respect to an average value. That is, in the case of surface roughness, when the surface skewness (Rsk) has a negative value, it means that the tendency of a surface in which a recessed portion is formed from an approximately or relatively flat surface is large. On the other hand, in the case of surface roughness, when the surface skewness has a positive value, it means that a surface having a portion protruding from an approximately or relatively flat surface tends to be large. In addition, when the surface skewness is 0, it means that the roughness is symmetrical up and down from the average value. You can refer to the image below for skewness.

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 nozzle 60 may be disposed on 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 protrusion pattern 230 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 T1 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 T2 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. In another embodiment, the protrusion pattern 230 may have an approximately '+' shape or an approximately 'X' shape in a plan view. In another embodiment, the plurality of protrusion patterns form a cluster with a predetermined regularity, and the cluster patterns may be arranged regularly or irregularly.

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.

In addition, as will be described later, the protrusion pattern 230 may have a first pore P1 and a second pore P2 contributing 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 pores P1 and the second pores P2. The first pore (P1) and the second pore (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 pores P1 and the second pores 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 pores + area occupied by the second pores).

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 again due to the reduction of the actual contact pressure and the restriction of the flow of the slurry.

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 quadrangle 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 pore P1 and the second pore 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 pores 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 pore (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.

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 that requires control in the process and/or process equipment for forming the protrusion pattern 230, and excluding the length increased by the pores, it can mean the shortest distance between one point and another point. 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 210s of the base 210 to the upper end of the protrusion pattern 230 .

The height H of the protrusion pattern 230 may have a correlation with the minimum width W of the protrusion pattern 230 . That is, when the width ratio of the protrusion pattern 230 on the vertical section becomes too large, the polishing pad 11 rotates and in the process of closely contacting the polishing target substrate 50 in a planar direction, for example, the first direction (X) and the second direction (Y). Inclination or distortion in any direction in the plane to which it belongs may occur, and the designed polishing may not be fully performed. On the other hand, when the height H of the protrusion pattern 230 is too small, the life of the polishing pad 11 may be too short due to damage or abrasion occurring at the top of the protrusion pattern 230 as the polishing process is repeated.

In view of the above, the minimum height H of the protruding pattern 230 is about 0.5 to 2.5 times, or about 0.6 to 2.0 times, or about 0.7 to 1.8 times, or about the minimum width of the protruding pattern 230. 0.8 times to 1.7 times, or about 0.9 times to 1.6 times, or about 1.0 times to 1.5 times.

As described above, the protrusion pattern 230 may have porosity and a plurality of pores P. The plurality of pores P may include a first pore P1 , a second pore P2 , and a third pore P3 . In this specification, the term 'pore' may be used interchangeably with terms such as 'void'.

The first pore 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 pore contributing to an increase in the circumferential length L. That is, the first pores P1 may form indentations at the edge of the plane of the protrusion pattern 230 . The first pore P1 may have a shape such as a circular arc or an elliptical arc in a plan view.

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

In an exemplary embodiment, in a plan view, the area occupied by the pores exposed on the top of the protrusion pattern 230 with respect to the entire upper surface of any one protrusion pattern 230, that is, the first pore P1 and the second pore ( 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 pores P1 and the second pores P2 may be approximately uniformly distributed. When too many first pores P1 and second pores P2 are formed, that is, when the arrangement density is too high, too many first pores 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 number of the first pores P1 and the second pores P2 is 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 protruding pattern 230 . In the case of having an area ratio of the first pores (P1) and the second pores (P2) as described above, the first pores (P1) and the second pores (P2) causing an increase in the circumferential length do not exist Compared to that, the circumferential length of the protruding pattern 230 according to the present embodiment having the first pores 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 pores P1 and the second pores P2 on the upper surface of the protrusion pattern to the total area of the polishing pad 11, or the first pores P1 and the second pores per unit area ( The proportion of the area occupied by P2) may be about 0.01% to 25%, or about 0.5% to 20%, or about 1.0% to 15%.

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 Excavated elements in the case of having the pores (P) larger than the size and came to complete the present invention. 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 excluding the area occupied by the pores P from the upper area of the protrusion pattern 230 are When it is within the above range, excellent polishing properties may be exhibited.

The first pore P1 and the second pore P2 may have substantially the same size. Since the first pores P1 are located at the edge of the protrusion pattern 230 and do not have a complete circular or oval shape, the size (eg, diameter, particle size) of the first pores P1 is determined by the first pores 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 pores (P1) and the second pores (P2) have an elliptical or distorted shape rather than a complete circle shape, the size of the pores is the diameter of the virtual circle corresponding to the area of the pores, such as an ellipse, that is, equivalent diameter.

The size of the pores P, that is, both the distribution range of the diameter and the average diameter may 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, a 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 pores P1 may be located, or even the size of the first pores 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. In addition, the difference between the area excluding only the area of the first pores P1 from the upper area of the protrusion pattern 230 and the area excluding the entire area of the pores P from the upper area of the protrusion pattern 230 increases, It may not show the designed polishing rate.

On the other hand, if the average diameter of the pores (P) is too fine, the durability of the protrusion pattern 230 may be deteriorated due to the first pores P1 located at the edge of the protrusion pattern 230 and may cause a polishing defect.

In spite of the difference in the average diameter of the pores (P), it is possible to improve the intended polishing properties by configuring the arrangement density and distribution of the pores, such as the area occupied by the pores (P), as described above.

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 third pores P3 . That is, the third pores P3 mean pores exposed only on the side surface, not on the upper surface of the protrusion pattern 230 . 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 protrusion pattern 230, that is, the third pore P3, is not exposed to the upper surface of the protrusion pattern 230, that is, the polishing surface, and the first pore ( It has a difference from P1) and the second pore 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 predetermined grooves formed by the third pores P3, and the grooves may be used to contribute to an increase in the flow of the slurry 70 . The size of the third pores (P3), etc. have been described together with the first pores (P1) and the second pores (P2), so the overlapping description will be omitted.

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 pore P3 is exposed, and may be changed to the above-described first pore P1 .

As described above, the size of the pores (P) is a very important factor in that it affects the polishing efficiency by causing an increase in the circumferential length on the polishing surface and a change in the polishing area by the pores (P1, P2) in a plan view. to be. In addition, in particular, in the case of the third pore P3 , it may be exposed to the side surface of the protrusion pattern 230 to affect durability of the protrusion pattern 230 .

In this view, on any cross-section, the ratio of the sum of the heights occupied by the third pores P3 to the vertical height H of the protrusion pattern 230 is about 10% to 50%, or about 15% to 50%, or from about 20% to 50%, or from about 20% to 45%, or from about 20% to 40%. Also, the average diameter of the third pores P3 may be in the range of about 5% to 15%, or about 10% to 15% of the height H of the protrusion pattern 230 .

When one diameter of the third pores (P3), or the sum of the diameters of the third pores (P3) is too large, the protrusion pattern 230 has too much fluidity in the third direction (Z), and/or the protrusion pattern ( 230) may be degraded. Therefore, it is preferable to make the sum of the diameter of one third pore P3 and the length in the third direction Z occupied by the plurality of third pores P3 arranged in the third direction Z within the above range. can

As described above, the first pores (P1) and the second pores (P2) contribute to an increase in the peripheral length of the edge of a certain protrusion pattern 230, and can also affect the polishing area formed by the protrusion pattern 230. have. In addition, the third pores 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.

In some embodiments, pores are substantially absent, a relatively small number, or a relatively small number of pores on the remaining portion of the pattern layer 200 except for the protrusion pattern 230 , that is, on the surface such as the upper surface 210s of the base 210 . Pores of any size may be present.

For example, the surface roughness Rsk_base defined as the skewness of the upper surface 210s of the base 210 is formed by the first pores P1 to the third pores P3 of the protrusion pattern 230 surface. It may be larger than the surface roughness (Rsk_pattern) defined by the skewness. The surface skewness of the surface of the protrusion pattern 230 may have a negative value, and the upper surface 210s of the base 210 may have a negative value, or 0 or a positive value.

Although the present invention is not limited thereto, when the pattern layer 200 of the polishing pad 11 is formed using a laser or the like, at least some of the pores are melted or collapsed in the process of irradiating the laser to the surface of the base 210 . This may be because the skewness of the upper surface 210s of the base can be adjusted in a positive direction rather than the skewness on the protrusion pattern 230 by using the feature. The surface roughness may be measured for an inspection area of about 0.1 mm ^{2 or more.}

Accordingly, a value obtained by subtracting the skewness Rsk_base of the upper surface of the base 210s from the skewness Rsk_pattern of the surface of the protrusion pattern 230, for example, the upper surface Rsk_pattern may have a positive value greater than zero. That is, the value of (Rsk_base - Rsk_pattern) > 0 may be the value of the surface state before applying the pad to polishing or during processing by applying the pad to polishing.

When the upper portion of the protrusion pattern 230 is manufactured to have negative skewness, the portion of the protrusion pattern 230 excluding the pores is flat. (50c) By increasing the skewness of the upper surface of the base 210s in a positive direction compared to the skewness of the protruding pattern 230 while at the same time improving the characteristics for flatly grinding the pattern, it is too deep in the upper surface of the base 210s. It is possible to improve the controllable properties so that the slurry flow is not stagnated by the pores or residual abrasive particles and abrasive by-products in the deep pores can be easily removed from the base 210 without stagnation.

For another example, the arrangement density of pores (not shown) located on the upper surface 210s of the base 210 is formed by the first pores P1 to the third pores P3 of the protrusion pattern 230 surface. may be smaller than their arrangement density. Specifically, with respect to the total area of the polishing pad 11, the ratio of the area occupied by the pores of the upper surface of the base 210 except for the first pores P1 and the second pores P2 is about 5% to 50%, or about 10% to 30%.

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, only the overcoating layer 50c protruding relatively downward convexly is selectively polished, and physical pressure is minimized on the overcoating layer 50c which is relatively concavely indented to the upper side, thereby damaging the elements 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, the description of the same or extremely similar configuration to the above-described embodiment will be omitted, and this will be clearly understood by those skilled in the art from the accompanying drawings.

11 is a planar layout of a polishing pad according to another embodiment of the present invention. 12 is an enlarged perspective view showing an enlarged portion A of FIG. 11 . 13 is a cross-sectional view taken along line B-B' of FIG. 12 .

11 to 13 , the polishing pad 12 according to the present embodiment is different from the above-described embodiment in that it has a trench 300 formed in the pattern layer 202 .

The trench 300 may serve as a channel for transporting and discharging the slurry, etc. dropped on the upper surface of the polishing pad 12 . 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 linear radiation trench 310 extending in the first direction (X), the second direction (Y), and/or diagonally. The radiation trench 310 may have a shape extending in a substantially radial direction from the center of the circular polishing pad 12 . 11 illustrates a case in which eight radiation trenches 310 inclined in the first direction (X), the second direction (Y), and 45 degrees are formed.

Accordingly, the polishing pad 12 may be divided into eight sectoral regions having a central angle of approximately 45 degrees. At least a portion of the radiation trench 310 of the polishing pad 12 according to the present embodiment may extend in the arrangement direction of the protrusion patterns 230 , that is, in the first direction (X) and the second direction (Y). . However, the present invention is not limited thereto.

The radiation trench 310 may induce the slurry to move or flow in the radial outer direction of the polishing pad 12 due to centrifugal force generated according to the rotation of the polishing pad 12 . Through this, even when the slurry is dropped without moving the nozzle of the polishing apparatus, the slurry can be applied to the entire surface of the polishing pad 12, and excessive agglomeration is prevented in a portion to improve the utilization efficiency of the slurry can do it In some embodiments, the radiation trench 310 may be configured to increase in depth toward the outer direction.

In addition, the trench 300 may further include a concentric circle trench 320 arranged in concentric circles with respect to the center of the circular polishing pad 12 . 11 illustrates a case in which the number of concentric trenches 320 is three, of course, the present invention is not limited thereto.

Any concentric trench 320 may be provided to intersect the plurality of radiation trenches 310 . The concentric trench 320 may induce the slurry to move or flow in the rotational direction of the polishing pad 12 , ie, the circumferential direction, due to centrifugal force generated according to the rotation of the polishing pad 12 .

Although the present invention is not limited thereto, the slurry that preferentially flows in the outer direction of the polishing pad 12 by the radiation trench 310 may flow in the rotational direction of the polishing pad 12 by the concentric trench 320 . have. Therefore, forming the maximum width of the radiation trench 310 larger than the maximum width of the concentric trench 320 may be advantageous in terms of preventing agglomeration of the slurry. As a non-limiting example, the width of the radiation trench 310 is in the range of about 0.1 mm or more and 3.0 mm or less, or about 0.3 mm or more and 2.5 mm or less, or about 0.5 mm or more and 2.0 mm or less, or about 1.0 mm or more and 1.5 mm or less. can be in

In an exemplary embodiment, the inner wall of the trench 300 formed in the patterned layer 202 may have exposed pores. The pores exposed on the inner wall of the trench 300 may be defined as the fourth pores P4 . The average diameter of the fourth pores P4 is in the range of about 10 μm to 150 μm, or about 20 μm to 150 μm, or about 30 μm to 150 μm, or about 50 μm to 130 μm, or about 60 μm to 100 μm. there may be

On the other hand, substantially no pores, a relatively small number, or a relatively small size of pores may exist on the base surface of the trench 300 .

For example, the surface skewness Rsk of the base surface of the trench 300 may be greater than the surface skewness Rsk formed by the fourth pores P4 of the inner wall of the trench 300 . The surface skewness of the inner wall surface of the trench 300 may have a negative value, and the basal surface may have a negative value, or 0 or a positive value. More specifically, a value obtained by subtracting the surface skewness of the inner wall from the surface skewness of the basal surface may have a positive value greater than zero.

For another example, the arrangement density of pores (not shown) located on the base surface of the trench 300 may be smaller than the arrangement density of pores formed by the fourth pores P4 of the inner wall of the trench 300 . Specifically, the ratio of the area occupied by the pores of the base surface of the trench 300 may be about 5% to 50%, or about 10% to 30%.

The depth D1 of the trench 300 may be smaller than the thickness of the base 210 , for example, the maximum thickness. Accordingly, the support layer 100 may not be visually recognized through the trench 300 and may be covered by the remaining pattern layer 202 . In this specification, the depth D1 of the trench 300 means the shortest vertical length from the reference plane, that is, the upper surface of the base 210 to the lowermost base surface of the trench 300 .

Also, the depth of the trench 300 , for example, the depth D1 of the radiation trench 310 may be greater than the maximum height of the protrusion pattern 230 . As will be described later, the trench 310 may contribute to the fluidity of the pattern layer 202 . Accordingly, it may be desirable for the trench 310 to have a sufficient depth in terms of fluidity of the pattern layer 202 and tracking of the substrate to be polished.

14 is a cross-sectional view of a polishing pad according to another embodiment of the present invention, and is a cross-sectional view showing the same position as in FIGS. 6 and 13 described above.

Referring to FIG. 14 , the polishing pad 13 according to the present embodiment is different from the above-described embodiment of FIG. 13 in that the upper surface of the support layer 100 is partially visible through the trench 313 .

The depth D1 of the trench, eg, the radiation trench 313 , may be substantially equal to the thickness, eg, the maximum thickness, of the base 210 . Accordingly, the upper surface of the support layer 100 may be exposed through the trench 313 .

In the present embodiment, the trench including the radiation trench 313 and/or the concentric trenches (not shown) imparts a certain fluidity to the pattern layer 203 , and the protruding pattern 230 of the polishing pad 13 as described above. ) may follow the curve of the substrate to be polished. That is, the upper surface of the support layer 100 may be partially exposed by the trench 313 , and the base 210 of the pattern layer 203 may be spaced apart from each other based on the radiation trench. Any one of the pattern layers 203 spaced apart from each other is the same as described above in that it has an approximately sectoral shape in plan view.

By the pressure in the third direction (Z) applied to the pattern layer 200 according to the base 210 that is partitioned based on the radiation trench 313 and the like on one support layer 100 and separated from each other and spaced apart from each other It is possible to have fluidity in the planar direction, and it is possible to more flexibly follow the vertical along the curved surface of the substrate to be polished.

In addition, the first pores (P1) to the third pores (P1) of the protrusion pattern 230, and the fourth pores (P4) of the base 210 have been described above, and thus overlapping descriptions will be omitted.

15 is a cross-sectional view of a polishing pad according to another embodiment of the present invention, and is a cross-sectional view showing the same position as in FIGS. 6 and 13 described above.

Referring to FIG. 15 , the polishing pad 14 according to this embodiment is different from the embodiment of FIG. 14 described above in that the support layer 100 also has a partially recessed trench.

In an exemplary embodiment, the patterned layer 204 may have a first trench 314 , and the support layer 100 may have a second trench 414 . A depth D1 of the first trench 314 may be substantially equal to a thickness of the base 210 . A depth D2 of the second trench 414 may be smaller than a thickness of the support layer 100 .

The first trench 314 and the second trench 414 may be connected to each other while overlapping each other in the third direction Z. The first trenches 314 and the second trenches 414 may each include the aforementioned radial trenches and/or concentric trenches.

The support layer 100 may have a second trench 414 and provide a channel through which the slurry flows. In some embodiments, the inner wall of the second trench 414 of the support layer 100 may or may not have pores as well. For example, the average diameter of pores (not shown) of the inner wall of the second trench 414 of the support layer 100 may be greater than the average diameter of the fourth pores P4 . For another example, the arrangement density of pores (not shown) on the inner wall of the second trench 414 may be greater than the arrangement density of the fourth pores P4 on the inner wall of the first trench 314 .

In addition, the first pores (P1) to the third pores (P1) of the protrusion pattern 230, and the fourth pores (P4) of the base 210 have been described above, and thus overlapping descriptions will be omitted.

16 is a cross-sectional view of a polishing pad according to another embodiment of the present invention, and is a cross-sectional view showing the same position as in FIGS. 6 and 13 described above.

Referring to FIG. 16 , the polishing pad 15 according to the present embodiment is different from the embodiment of FIG. 15 described above in that the support layer 100 is penetrated by a trench.

The pattern layer 205 has a first trench 315 and the support layer 100 has a second trench 415 , and the first trench 315 and the second trench 415 are connected to each other by overlapping with each other as described above. same. In this embodiment, the second trench 415 may completely penetrate the support layer 100 . That is, the depth D2 of the second trench 415 may be substantially the same as the thickness of the support layer 100 . Accordingly, other components (not shown) under the polishing pad 15 may be visually recognized through the trenches 315 and 415 .

In addition, the first pores (P1) to the third pores (P1) of the protrusion pattern 230, and the fourth pores (P4) of the base 210 have been described above, and thus overlapping descriptions will be omitted.

17 is a cross-sectional view of a polishing pad according to another embodiment of the present invention, and is a cross-sectional view showing the same position as in FIGS. 6 and 13 described above.

Referring to FIG. 17 , the polishing pad 16 according to the present embodiment is different from the above-described embodiment of FIG. 6 and the like in that the upper surface of the base 210 of the pattern layer 206 has pores.

18 is a cross-sectional view of a polishing pad according to another embodiment of the present invention, and is a cross-sectional view showing the same position as in FIGS. 6 and 13 described above.

Referring to FIG. 18 , the polishing pad 17 according to the present embodiment is different from the embodiment of FIG. 6 and the like in that the pattern layer 207 is formed in a protruding pattern without a base. That is, in the present embodiment, the plurality of protrusion patterns disposed on the support layer 100 may be spaced apart from each other and may not be physically connected.

Hereinafter, a method of manufacturing a polishing pad according to an embodiment of the present invention will be described. 19 to 22 are views sequentially illustrating a method of manufacturing a polishing pad according to an embodiment of the present invention. 19 to 22 are cross-sectional views showing positions corresponding to those of FIG. 6 and the like, respectively.

First, referring to FIG. 19 , a porous pre-pattern layer 200a is prepared. 19 illustrates a case in which the pre-patterned layer 200a is disposed on the support layer 100 , but the present invention is not limited thereto, and only the pre-patterned layer 200a may be prepared without the support layer 100 . .

The pre-pattern layer 200a may be in a pre-cured state to have a predetermined porosity. The average diameter of the pores P of the pre-patterned layer 200a may be in the range of about 10 μm to 150 μm. Also, the diameter distribution of the pores P may be in the range of about 1 μm to 500 μm, or about 5 μm to 400 μm, or about 80 μm to 300 μm.

Next, referring further to FIG. 20 , the pre-patterned layer 200a is at least partially removed using the laser L. The pattern layer 200b removed by the laser L may include a base 210 and a plurality of protruding patterns 230 disposed on the base 210 .

A side surface of the protrusion pattern 230 formed by the laser L may have third pores P3 . In addition, the upper surface of the protrusion pattern 230 has the first pores (P1) and the second pores (P2) as described above. On the other hand, the upper surface 210s of the base 210 formed by the laser L has substantially no pores, or a relatively small number of pores compared to the surface of the protruding pattern 230, or a relatively smaller size of pores. can have only This may be because the pores are collapsed due to partial melting of the pre-pattern layer 200a in the portion irradiated by the laser L, but the present invention is not limited thereto.

Next, further referring to FIG. 21 , the pattern layer 200c is partially removed using a laser L to form a trench 300a in the pattern layer 200c. Specifically, a trench 300a is formed in the base 210 of the pattern layer 200c.

The inner wall of the trench 300a formed by the laser L may have fourth pores P4 . On the other hand, the base surface of the trench 300a formed by the laser L has substantially no pores, or has a relatively small number of pores compared to the inner wall of the trench 300a, or only a relatively smaller size of pores. have.

Next, referring further to FIG. 22 , a first trench 300b penetrating the pattern layer 200d is formed using a laser L, and the support layer 100 is partially removed to form a second trench in the support layer 100 . (300c) is formed.

Although not shown in the drawings, in some embodiments, a second trench penetrating through the support layer 100 may be formed using a laser.

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.

100: support layer
200: pattern layer
210: base
230: pattern layer
P1: first pore
P2: second pore
P3: third pore

Claims (15)

support layer; And as a pattern layer disposed on the support layer, including a pattern layer comprising a protruding pattern having a plurality of pores,
The protrusion pattern has pores exposed on the side,
The ratio of the sum of the heights occupied by the side pores to the vertical height of the protrusion pattern is in the range of 10% to 50%. The method of claim 1,
The average diameter of the pores is in the range of 20% to 40% of the vertical height of the protrusion pattern. According to claim 1,
The pattern layer includes a base and the plurality of protruding patterns disposed on the base,
A polishing pad in which a value obtained by subtracting the surface skewness (Rsk_pattern) of the protruding pattern surface from the surface skewness (Rsk_base) of the upper surface of the base is greater than zero. The method of claim 1,
The pattern layer includes a base and the plurality of protruding patterns disposed on the base,
The arrangement density of the pores on the upper surface of the base is smaller than the arrangement density of the pores on the surface of the protruding pattern. According to claim 1,
The pattern layer includes a base and the plurality of protruding patterns disposed on the base,
wherein the base has an at least partially recessed first trench. 6. The method of claim 5,
the base has exposed pores on the inner wall of the first trench;
An average diameter of the pores exposed on the inner wall of the first trench is in the range of 30 μm to 150 μm. 7. The method of claim 6,
The first trench penetrates through the base, and an upper surface of the support layer is at least partially exposed by the first trench. 6. The method of claim 5,
wherein the support layer is an at least partially recessed second trench, the polishing pad having a second trench connected to the first trench. 9. The method of claim 8,
the base has exposed pores on the inner wall of the first trench;
The support layer has pores exposed on the inner wall of the second trench,
The average diameter of the pores of the inner wall of the second trench is larger than the average diameter of the pores of the inner wall of the first trench. 6. The method of claim 5,
The first trench includes a plurality of radiation trenches extending radially from the center of the circular polishing pad, and concentric circle trenches having a concentric shape with respect to the center and connecting the plurality of radiation trenches,
a width of the radiation trench is greater than a width of the concentric trenches. 6. The method of claim 5,
The first trench does not penetrate through the base,
The surface roughness of the base surface of the first trench is smaller than the surface roughness of the inner wall of the first trench. preparing a patterned layer having porosity; and
Partially removing the patterned layer using a laser, including forming a base and a plurality of protruding patterns disposed on the base, and partially removing the patterned layer to have pores exposed on the side surfaces of the protruding pattern A method of manufacturing a polishing pad comprising the step of: 13. The method of claim 12,
The partially removing the pattern layer may include forming a trench in the base, and further comprising forming a trench to have pores exposed on an inner wall of the first trench. 13. The method of claim 12,
The partially removing the pattern layer may include forming a trench in the base, and further comprising forming a trench penetrating the base. 15. The method of claim 14,
disposing the pattern layer on a support layer; and
and at least partially removing the support layer through a trench through the base.

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