KR20230092626A - Polishing pad containing uniformly distriputed liquid pores and method for manufacturing the same - Google Patents

Abstract

The present invention is a polymer matrix; liquid microelements dispersed and embedded in the polymer matrix; and a polishing layer including pores defined by the liquid microelements and opened to the surface of the polishing surface by separation of the liquid microelements, wherein the liquid microelements contain a compound containing a hydrophobic group and a hydrophilic group. It provides a polishing pad and a manufacturing method thereof, characterized in that it comprises.

Description

Polishing pad containing uniformly distributed liquid pores and method for manufacturing the same}

The present invention relates to a polishing pad including uniformly distributed liquid pores and a manufacturing method thereof.

The chemical mechanical planarization / polishing (CHEMICAL MECHANICAL PLANARIZATION / CHEMICAL MECHANICAL POLISHING, hereinafter referred to as CMP) process is a process introduced for global planarization of semiconductor devices, and the trend is for large-diameter wafers, high integration, miniaturization of line widths, and multi-layered wiring structures. As a result, it is emerging as a more important process.

In the CMP process, polishing speed and flatness are important, and they are determined by the process conditions of polishing equipment and the polishing slurry and polishing pad, which are consumable members used. In particular, the polishing pad uniformly distributes the supplied polishing slurry on the wafer while in contact with the surface of the wafer, and allows a physical removal action to occur by the abrasive particles inside the polishing slurry and the surface protrusions of the polishing pad.

At this time, the surface of the polishing pad in direct contact with the wafer should be kept saturated with the polishing slurry so that the polishing slurry flows smoothly. To this end, techniques for forming fine holes (eg, pores) on the surface of the polishing pad are disclosed in US Patent No. 5,578,362, Korean Patent Publication No. 2001-2696, and Korean Patent Publication No. 2001-55971.

As such, it is very important to maintain a state in which the polishing slurry is saturated in the polishing pad in order to increase the role and performance of the polishing pad in the CMP process. Therefore, various grooves are formed on the polishing pad to form a large flow of slurry, and in addition, fine holes are formed on the surface of the polishing pad by opening the microporous material as described above.

Although technology has been developed in the direction of attempting to form various patterns in relation to the groove formation, the porous pore technology for forming fine holes is limited to using a specific pore formation method.

That is, each of the conventional pore forming methods has advantages and disadvantages, and in the actual CMP process, the process is adjusted and used in consideration of these advantages and disadvantages.

However, as fineness and sophistication are increasingly required in the semiconductor manufacturing process, there is a growing demand for developing a technology for creating more advanced porous pores on the polishing pad.

Korean Patent Publication No. 10-2001-2696

The present invention has been made to solve the above problems of the prior art, and provides excellent polishing uniformity and polishing rate during a chemical mechanical planarization / polishing (CMP) process by including uniformly distributed liquid pores, An object of the present invention is to provide a polishing pad capable of providing excellent polishing characteristics with improved wettability and a manufacturing method thereof.

In addition, the present invention can uniformly collect and supply the polishing slurry, thereby achieving polishing uniformity, enabling in-situ flatness inspection without forming a separate transparent window, and preventing scratches on the surface to be polished. It is an object of the present invention to provide a polishing pad that does not generate and a manufacturing method thereof.

In order to achieve the above object, the present invention

polymer matrix;

liquid microelements dispersed and embedded in the polymer matrix; and

A polishing layer including pores defined by the liquid microelements and opened to the surface of the polishing surface by separation of the liquid microelements;

The liquid microelements provide a polishing pad containing a compound containing a hydrophobic group and a hydrophilic group.

In addition, the present invention

a) mixing a material for forming a liquid microelement with a material for forming a polymer matrix;

b) gelling and curing the mixture to form a polymer matrix and liquid microelements embedded in the polymer matrix; and

c) processing the product manufactured in step b) into a shape of a polishing pad;

The liquid microelement-forming material includes a compound containing a hydrophobic group and a hydrophilic group, and a method for manufacturing a polishing pad is provided.

The polishing pad of the present invention includes uniformly distributed liquid pores, thereby providing excellent polishing uniformity and polishing speed during a chemical mechanical planarization/polishing (CMP) process, and providing excellent polishing characteristics due to improved wettability. do.

In addition, it is possible to uniformly collect and supply the polishing slurry, so that polishing uniformity can be achieved, flatness can be inspected in situ without forming a separate transparent window, and scratches cannot be generated on the surface to be polished. provides an effect that does not

In addition, the present invention provides a method for manufacturing a polishing pad capable of efficiently manufacturing the polishing pad.

1 is a cross-sectional view of a polishing pad according to an embodiment of the present invention;
2 is a schematic diagram of a polishing apparatus equipped with the polishing pad of FIG. 1;
3 is an enlarged image of a cross section of a polishing layer of a polishing pad according to an embodiment of the present invention;
Figure 4 is a graph showing the measured ramp up performance of the polishing pad according to the present invention,
5 is a graph showing the polishing performance of the polishing pad according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. Like reference numerals have been assigned to like parts throughout the specification.

It should be understood that when a component is referred to as being “connected to, provided with, or installed” to another component, it may be directly connected or installed to the other component, but other components may exist in the middle. .

In the present invention, the meaning of "including ~~" means that other components may be included in addition to certain components included, but also means a case consisting of only one of the above components without other components.

A conventional polishing pad including liquid-phase pores has a problem in that the ramp-up is insufficient compared to a polishing pad including gas-phase pores because the liquid microelements embedded in the polishing layer are non-uniformly distributed in the polymer matrix. That is, due to the non-uniform distribution as described above, the speed at which pores are replaced by the polishing slurry on the polishing surface is delayed, and accordingly, the speed at which the process temperature is reached is slow.

Therefore, the present invention is characterized by solving the above problem and providing a polishing pad in which liquid microelements are uniformly distributed in a polymer matrix.

1 is a cross-sectional view of a polishing pad according to an embodiment of the present invention, and FIG. 2 is a schematic view of a polishing apparatus equipped with the polishing pad of FIG. 1 .

As shown in FIG. 1 , the polishing pad 100 of the present invention includes a polymer matrix 120; liquid microelements 141 dispersed and embedded in the polymer matrix; and a polishing layer 120 including; and pores 141' defined by the liquid microelements and opened to the surface of the polishing surface by separation of the liquid microelements,

The liquid microelements 141 are characterized by including a compound containing a hydrophobic group and a hydrophilic group.

In the above, the meaning that the pores 141' are defined by the liquid microelements and opened by the separation of the liquid microelements means that the liquid microelements embedded in the abrasive layer 120 leak to the outside. This means that the area where was left as a pore 141 to capture certain substances from the outside.

As the polishing layer 120 of the polishing pad 100 is worn during the polishing process, the embedded liquid microelements 141 are continuously exposed to the polishing layer surface 160 to form pores 141', which form the polishing slurry ( 13) is replaced by Therefore, since only the polymer matrix exists on the polishing surface 160, uneven wear of the polishing pad 100 does not occur, and the silicon wafer 7 to be polished can be uniformly polished. That is, since a polymer having high hardness does not exist on the surface of the polishing layer, the wafer is not scratched.

In one embodiment of the present invention, the polishing layer surface 160 may be further formed with textures or patterns including flow channels that facilitate the transfer of the polishing slurry.

In one embodiment of the present invention, the polishing pad 100 may further include a support layer 110 supporting the polishing layer 120 . As shown in FIGS. 1 and 2 , the support layer 110 is a portion for attaching the polishing pad 100 to the platen 3 . The support layer 110 is composed of a material having restorability in response to a force that presses the silicon wafer 7, which is an object to be polished, loaded on the head 5 facing the platen 3, and the polishing layer 120 formed thereon. ) with a uniform elastic force corresponding to the silicon wafer 7. Therefore, it is mainly made of a non-porous solid homogeneous elastic material, and has a lower hardness than the abrasive layer 120 formed thereon.

In addition, at least a part of the supporting layer 110 is transparent or translucent, so that the light beam 170 used to detect the flatness of the surface to be polished can pass through. In FIG. 2, the wafer 7 on which a film to be polished such as a metal or insulating layer is formed is exemplified as a subject to be polished, but various substrates such as a substrate on which a TFT-LCD is to be formed, a glass substrate, a ceramic substrate, and a polymer plastic substrate are to be polished. Of course, it can be used as a target. In some cases, the polishing pad 100 may be formed without the supporting layer 110 .

In addition, although FIG. 2 shows a case where the shape of the polishing pad 100 is circular to be suitable for the rotary polishing device 1, it can be transformed into various shapes such as rectangular and square depending on the shape of the polishing device 1 is of course

In the polishing pad 100 of the present invention, the polishing layer 120 is a portion that directly contacts the wafer 7 to be polished, as shown in FIG. 2 . The polishing layer 120 is preferably formed of a material insoluble in the polishing slurry 13, which is a chemical solution for planarization. For example, as shown in FIG. 2 , the polishing slurry 13 supplied through the nozzle 11 of the polishing equipment 1 may be formed of a material that cannot penetrate.

The polymer matrix 130 constituting the polishing layer 120 may be a hydrophilic polymer matrix, a hydrophobic polymer matrix, or a composite polymer matrix having both hydrophilic and hydrophobic properties.

The polymer matrix is, for example, polyurethane, polyether, polyester, polysulfone, polyacrylic, polycarbonate, polyethylene, polymethyl methacrylate, polyvinyl acetate, polyvinyl chloride, polyethylene imine, polyether sulfone, poly It may be any one selected from the group consisting of ether imide, polyketone, melamine, nylon, fluorocarbon and the like, or a mixture thereof. Among these, those made of polyurethane are preferred. Polyurethane can be obtained from a two-component, low-viscosity liquid urethane composed of an isocyanate prepolymer and a curing agent. The polyurethane may be finally formed by reacting a polyurethane prepolymer with a curing agent.

As the curing agent, amines such as 4,4-methylene-bis(2-chloroaniline) (hereinafter referred to as MOCA) or various polyether-based and polyester-based polyols may be used. The physical properties of the polyurethane can be controlled by various combinations of components.

Of course, the above-described polishing layer may be composed of various materials other than those described above.

The hydrophilic polymer matrix constituting the polymer matrix 130 may be one in which a hydrophilic compound is introduced by chemical bonding or mixing with a material for forming the polymer matrix.

The hydrophilic compound is composed of polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, sorbitol fatty acid ester, etc. It may be any one selected from the group or a mixture thereof.

In the present invention, the "alkyl" means a substituted or unsubstituted alkyl group having 2 to 15 carbon atoms.

As the hydrophilic compound, polyethylene glycol having a weight average molecular weight of 200 to 10,000 may be preferably used.

The hydrophilic polymer matrix may preferably include, for example, a material formed by chemically bonding or mixing an isocyanate prepolymer and 1 to 20 parts by weight of a hydrophilic compound based on 100 parts by weight of the isocyanate prepolymer.

In one embodiment of the present invention, the polishing layer 120 may further include pores formed by injection of an inert gas, a capsular foaming agent, and a chemical foaming agent.

The inert gas may mean a chemically stable gas because its valence is '0', such as helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), etc. included in these inert gases. Furthermore, the inert gas corresponds to any gas that does not react with the polymer matrix, for example, does not participate in the urethane reaction, such as N2, in addition to elements of group 8 on the periodic table.

The foaming agent is mixed with a predetermined raw material and generates a large amount of bubbles by vaporization or reaction by heat, and can be largely divided into chemical foaming agents and physical foaming agents.

Since the chemical foaming agent foams in carbon dioxide generated by reaction with water by using the activity of the isocyanate group, water is used as the foaming agent, and the physical foaming agent mixes gas or uses a decomposition type or evaporation type foaming agent to increase the reaction heat. It does not participate in the polymer reaction because it forms bubbles by raising it. Since the types and characteristics of these foaming agents are already known, a detailed description thereof will be omitted.

In one embodiment of the present invention, the liquid microelements 141 may be included in an amount of 5 to 60% by weight, preferably 20 to 50% by weight, based on the total weight of the polishing layer 120, and more preferably It may be included in 20 to 40% by weight. When the amount of the liquid microelements exceeds 60% by weight, the size of the liquid microelements 140 increases, and as a result, the size of the pores 141' formed on the pad surface 160 increases. In this case, a relatively high polishing rate is exhibited due to the large amount of collected polishing slurry particles, but this makes precise polishing difficult, and when the polishing slurry contains non-uniformly large particles, the large particles of the polishing slurry are collected to cause scratches on the wafer. can In addition, when the amount of the liquid microelements 141 is less than 5% by weight, the size of the liquid microelements 141 is reduced, and consequently, the size of the pores 141' formed on the pad surface 160 is reduced. When the size of the pores 14' is reduced, the amount of collected polishing slurry particles is small, enabling precise polishing and filtering large particles included in the polishing slurry without capturing them, thereby reducing the occurrence of scratches on the wafer. However, an excessive amount of liquid material leaks out during processing, making it difficult to handle the molding, and the manufactured polishing pad has a disadvantage in that it exhibits a low polishing rate.

In one embodiment of the present invention, the polishing layer 120 may include the polymer matrix 160 in an amount of 25 to 50% by weight based on the total weight of the polishing layer. In addition, the polishing layer 120 may contain 25 to 50% by weight of a curing agent as components other than the liquid microelements and the polymer matrix.

In one embodiment of the present invention, the liquid microelements may be uniformly distributed in the polymer matrix and may have a spherical shape. However, the shape of the liquid microelements is not limited to the spherical shape, and may be variously formed such as an elliptical shape or an amorphous shape.

In one embodiment of the present invention, the average diameter of the liquid microelements and the pores may be 1 μm to 60 μm. The average diameter is preferably 5 to 40 μm, and may be more preferably 10 to 30 μm. When the average diameter is within the above range, it is most suitable for collecting and supplying the abrasive slurry 13. However, the diameter may vary depending on the type of abrasive slurry 13 used, and the size of the embedded liquid microelements 141 may also vary accordingly.

In one embodiment of the present invention, it may be preferable that the liquid microelement is a water-soluble liquid material dissolved in a polishing solution.

The liquid microelements include a compound containing a hydrophobic group and a hydrophilic group, and the compound may preferably have a molecular weight of 300 to 5,000.

In one embodiment of the present invention, the compound containing the hydrophobic group and the hydrophilic group may be a compound formed by an ester reaction between a fatty acid and a hydrophilic compound. The esterification reaction may be performed in the absence of a solvent or under a solvent, and as the solvent, a hydrocarbon compound having a boiling point of 120° C. or higher and not containing active hydrogen may be preferably used, but is not limited thereto.

The fatty acid may be any one selected from the group consisting of acetic acid, laurylic acid, oleic acid, palmitic acid, stearic acid, linoleic acid, and the like, or a mixture thereof.

The hydrophilic compound is composed of polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, sorbitol fatty acid ester, etc. It may be any one selected from the group or a mixture thereof.

As the hydrophilic compound, polyethylene glycol having a weight average molecular weight of 200 to 4,000 may be preferably used.

In one embodiment of the present invention, the compound containing the hydrophobic group and the hydrophilic group has 1 to 95% by weight, preferably 2 to 50% by weight, more preferably 5 to 20% by weight of the hydrophilic group in the molecule. may be %.

When the weight of the hydrophilic group is less than 1% by weight, the phase separation of the liquid pore material does not occur, which is not effective in forming pores. In addition, if it exceeds 95% by weight, it is not preferable because problems such as reduction in polishing holding power and shortened lifespan occur due to a decrease in abrasion resistance of the polishing pad.

In addition, in the compound including the hydrophobic group and the hydrophilic group, the weight of the hydrophobic group in the molecule may be 5 to 99% by weight, preferably 50 to 98% by weight, and more preferably 80 to 95% by weight.

If the weight of the hydrophobic group is less than 5% by weight, it is not preferable because abrasion problems occur, and if it exceeds 99% by weight, it is not preferable because the problem of pore formation, polishing uniformity, polishing rate, and wettability are lowered .

In one embodiment of the present invention, the compound including the hydrophobic group and the hydrophilic group may be, for example, a compound represented by Formula 1 below.

[Formula 1]

In Formula 1 above

n may be 5 to 300,

The R ₁ and R ₂ are the same as or different from each other, and may each independently be a substituted or unsubstituted alkyl group having 1 to 17 carbon atoms, an alkenyl group, or an alkynyl group.

In the present invention, when liquid microelements are formed using the compound containing the hydrophobic group and the hydrophilic group, the principle of improving the wetting property will be described as follows.

As shown in the figure above, for example, when a polyurethane prepolymer is used as the polymer matrix material of the polishing layer, as shown above, a hydrophilic group is included in the polymer matrix structure. Therefore, when the hydrophilic group is also included in the liquid microelement material, the dispersion of the liquid microelements can be improved, and the wettability of the polishing pad is also improved.

In addition, the present invention

a) mixing a material for forming a liquid microelement with a material for forming a polymer matrix;

b) gelling and curing the mixture to form a polymer matrix and liquid microelements embedded in the polymer matrix; and

c) processing the product manufactured in step b) into a shape of a polishing pad;

The liquid microelement-forming material relates to a method for manufacturing a polishing pad including a compound containing a hydrophobic group and a hydrophilic group.

All of the contents of the polishing pad described above may be equally applied to the manufacturing method. Therefore, descriptions of overlapping contents are omitted.

In step a), the material for forming the polymer matrix may include, for example, a material formed by chemically bonding or mixing an isocyanate prepolymer and 1 to 20 parts by weight of a hydrophilic compound based on 100 parts by weight of the isocyanate prepolymer. there is.

Specifically, the material for forming the polymer matrix may be a polyurethane prepolymer.

The compound including the hydrophobic group and the hydrophilic group may be a compound formed by esterification of a fatty acid and a hydrophilic compound.

The fatty acid may be any one selected from the group consisting of acetic acid, laurylic acid, oleic acid, palmitic acid, stearic acid, linoleic acid, and the like, or a mixture thereof.

The hydrophilic compound is composed of polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, sorbitol fatty acid ester, etc. It may be any one selected from the group or a mixture thereof.

Step b) includes a process of injecting a mixture of a material for forming a polymer matrix and a material for forming liquid microelements into a mold having a predetermined shape to gel and harden the mixture. The gelation reaction may proceed for 5 to 30 minutes at 80 to 90 ° C, and the curing reaction may proceed for 20 to 24 hours at 80 to 120 ° C, but the specific process temperature and time may vary in order to find optimal conditions. Of course it can be.

Step c) includes a process of processing the cured product into a predetermined shape. The processing includes demolding, cutting, surface processing, and cleaning. Specifically, first, the cured reactant is taken out of the mold and cut to have a predetermined thickness, shape, and shape, and surface processing and cleaning may be performed by a known method. Meanwhile, it is also possible to form the abrasive layer 120 in a sheet shape by a known method in the field of polymer sheet manufacturing, such as casting and extrusion molding, in order to improve productivity.

The machining process may include a process of forming grooves of various shapes on the surface of the polishing layer 120 to allow the polishing slurry 13 to be evenly supplied to the working surface of the polishing layer 120 .

The liquid microelements 141 on the surface of the polishing layer 160 are eluted by the cleaning process, and open pores 141' are distributed on the surface of the polishing layer 160. At this time, it is preferable to perform the cleaning process using a cleaning solution that prevents the eluted liquid microelements 141 from remaining on the surface 160 of the polishing layer.

Although the polishing pad 100 can be completed with only the polishing layer 120 prepared above, if necessary, the support layer 110 is manufactured by a method widely known in the field of manufacturing the polishing pad 100 and the support layer 110 The polishing pad 100 may be completed by combining the polishing layer 120 with the polishing layer 120 .

Hereinafter, examples will be described in detail to explain the present invention in detail. However, the embodiments according to the present invention can be modified in many different forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

Examples 1 - 4 and Comparative Examples 1 - 3: Manufacture of polishing pads

Step 1) Production of polyurethane prepolymer

80 g of TDI (toluene diisocyanate) and 400 g of H12MDI (4,4'-diisocyanato dicyclohexylmethane) were added and the temperature was maintained at about 30°C. Here, 320 g of PTMG (Poly (tetramethylene ether) glycol, Mw: 1000) was dividedly added twice, and the reaction temperature was maintained at about 70 ° C. Thereafter, 120 g of polyethylene glycol (Mw: 2000) and 140 g of polypropylene (Mw: 1000) were added and reacted while maintaining the temperature at 80 °C.

Thereafter, 30 g of 1,4-butylene glycol was added and reacted at 80° C. to prepare a polyurethane prepolymer having an NCO of 11.5 to 12.5%.

Step 2) Manufacture of polishing pad

A hydrophobic liquid microelement material (Formula 3) composed of the polyurethane prepolymer and hydrocarbon prepared in step 1, a hydrophilic liquid microelement material (Formula 4), and a liquid microelement material containing hydrophilic and hydrophobic groups (Formula 2), MOCA (4,4-methylenenis (2-chloroaniline) as a curing agent was mixed in the composition ratio shown in Table 1 below to prepare a cake, and the cake was injected into a square mold, gelled for 30 minutes, and then heated to 100 ° C. Cured in an oven for 20 hours.

The cured product prepared above was taken out of the mold, cut and washed to prepare a polishing pad.

[Formula 2]

In the above formula, n is 50.

In the case of a weight ratio (95 / 5) of the hydrophobic part and the hydrophilic part, n is 10 (Example 1).

In the case of a weight ratio (90 / 10) of the hydrophobic part and the hydrophilic part, n is 20 (Example 2).

In the case of a weight ratio (80 / 20) of the hydrophobic part and the hydrophilic part, n is 50 (Example 3).

In the case of a weight ratio (50 / 50) of the hydrophobic part and the hydrophilic part, n is 100 (Example 4).

[Formula 3]

[Formula 4]

In the above formula, n is 50.

liquid microelement material Liquid microelement material content (% by weight) Weight ratio of Prepolymer/MOCA Hydrophobic or hydrophilic liquid microelement material Liquid microelement material containing hydrophilic and hydrophobic groups Comparative Example 1 Formula 3
(hydrophobic) - 40 100/38 Comparative Example 2 Formula 3 (hydrophobic) - 25 100/38 Comparative Example 3 Formula 4 (hydrophilic) - 25 100/38 Example 1 - Formula 2 Weight ratio of hydrophobic and hydrophilic groups
(95/5) 25 100/38 Example 2 - Formula 2 Weight ratio of hydrophobic and hydrophilic groups
(90/10) 25 100/38 Example 3 - Formula 2 Weight ratio of hydrophobic and hydrophilic groups
(80/20) 25 100/38 Example 4 - Formula 2 Weight ratio of hydrophobic and hydrophilic groups
(50/50) 25 100/38

Note) MOCA: 4,4-methylenenis (2-chloroaniline

Experimental Example 1: Evaluation of Physical Properties of Polishing Pad

Physical properties of the polishing pads prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were measured as follows, and the results are shown in Table 2.

(1) hardness measurement

The hardness of the polishing pad was measured using a durometer (ASKER, shore D).

(2) Pore size measurement

FE-SEM (scanning electron microscope, manufactured by JEOL) was used to

The size of the pores was measured.

(3) Evaluation of wetting

The polishing pad was mounted on a CMP evaluation device, and surface wetting was visually observed during break-in by the disk under the supply of DI water to evaluate the wetting property.

liquid pore material Pad Hardness (D) Pore size (㎛) Need Break in time
[Wetting property, visual confirmation] Hydrophobic liquid pore material Liquid pore material containing hydrophilic and hydrophobic groups Comparative Example 1 Formula 3 - 54 31 20min Comparative Example 2 Formula 3 - 57 25 20min Comparative Example 3 formula 4 - 56 5 2min Example 1 - Weight ratio of hydrophobic part and hydrophilic part of Formula 2
(95/5) 56 30 5min Example 2 - Weight ratio of hydrophobic part and hydrophilic part of Formula 2
(90/10) 56 23 5min Example 3 - Weight ratio of hydrophobic part and hydrophilic part of Formula 2
(80/20) 56 17 3min Example 4 - Weight ratio of hydrophobic part and hydrophilic part of Formula 2
(50/50) 56 10 2min

Experimental Example 2: Performance evaluation of polishing pad

The polishing pads prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were mounted in CMP evaluation equipment and their performance was evaluated under the conditions shown in Table 3 below.

Equipment GnP-Poli762 300mm Polisher Wafer Pressure [psi] R-ring 5.0 Membrane 3.8 Rotation[rpm] Platen 93 Carrier 87 Conditioner Load [lbf] 6 Rotation[rpm] 85 Sweep [cycle/min] 14 Type 80C1 (Saesol) Slurry Flow[ml/min] 240 SP6700@Cabot (1:2, 4%H ₂ O ₂₎

(1) Ramp up evaluation

Ramp up was measured by measuring the real-time pad surface temperature during the CMP process of 1 min under the CMP conditions of Table 3 above. The measurement results are shown in FIG. 4 .

(2) Evaluation of polishing performance

Using a tungsten (W) wafer, the wafer thin film thickness before and after CMP was measured when the CMP process was performed for 1 min under the CMP conditions of Table 3 above, and the polishing performance was calculated from the thickness change rate. The measurement results for the polishing performance are shown in FIG. 5 .

Claims (23)

polymer matrix;
liquid microelements dispersed and embedded in the polymer matrix; and
A polishing layer including pores defined by the liquid microelements and opened to the surface of the polishing surface by separation of the liquid microelements;
The liquid microelements include a compound containing a hydrophobic group and a hydrophilic group. According to claim 1,
The polishing pad according to claim 1 , wherein the polymer matrix is a hydrophilic polymer matrix, a hydrophobic polymer matrix, or a composite polymer matrix having both hydrophilic and hydrophobic properties. According to claim 2,
The hydrophilic polymer matrix is a polishing pad, characterized in that a hydrophilic compound is introduced into the material for forming the polymer matrix by chemical bonding or mixing. According to claim 3,
The hydrophilic polymer matrix comprises a material formed by chemically bonding or mixing an isocyanate prepolymer and 1 to 20 parts by weight of a hydrophilic compound based on 100 parts by weight of the isocyanate prepolymer. According to claim 3 or 4,
The hydrophilic compound is composed of polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, and sorbitol fatty acid ester. A polishing pad, characterized in that any one selected from the group or a mixture thereof. According to claim 5,
The polishing pad, characterized in that the hydrophilic compound is polyethylene glycol having a weight average molecular weight of 200 to 10,000. According to claim 1,
The polishing pad, characterized in that the liquid microelement is included in 5 to 60% by weight with respect to the total weight of the polishing layer. According to claim 1,
The polishing pad, characterized in that the surface of the polishing surface is worn or ground by a polishing process, and the embedded liquid microelements are separated from the surface to form continuously opened pores. According to claim 1,
The polishing pad, characterized in that the embedded liquid microelements are spherical microelements uniformly distributed in the polymer matrix. According to claim 1,
The polishing pad, characterized in that the average diameter of the liquid microelements and the pores are 1㎛ to 60㎛. According to claim 1,
The polishing pad, characterized in that the liquid microelement is a water-soluble liquid material dissolved in a polishing solution. According to claim 1,
The polishing pad, characterized in that the compound containing the hydrophobic group and the hydrophilic group has a molecular weight of 300 to 5,000. According to claim 1,
The polishing pad, characterized in that the compound containing the hydrophobic group and the hydrophilic group is a compound formed by an ester reaction of a fatty acid and a hydrophilic compound. According to claim 13,
The abrasive pad, characterized in that the fatty acid is any one selected from the group consisting of acetic acid, laurylic acid, oleic acid, palmitic acid, stearic acid, and linoleic acid, or a mixture thereof. According to claim 13,
The hydrophilic compound is composed of polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, and sorbitol fatty acid ester. A polishing pad, characterized in that any one selected from the group or a mixture thereof. According to claim 13,
The hydrophilic group comprises a polyethylene glycol derivative having a weight average molecular weight of 200 to 4,000. According to claim 13,
The polishing pad, characterized in that the weight of the hydrophilic group in the molecule of the compound containing the hydrophobic group and the hydrophilic group is 1 to 95% by weight. According to claim 17,
The polishing pad, characterized in that the weight of the hydrophobic group in the molecule of the compound containing the hydrophobic group and the hydrophilic group is 1 to 95% by weight. a) mixing a material for forming a liquid microelement with a material for forming a polymer matrix;
b) gelling and curing the mixture to form a polymer matrix and liquid microelements embedded in the polymer matrix; and
c) processing the product manufactured in step b) into a shape of a polishing pad;
The method of manufacturing a polishing pad according to claim 1 , wherein the liquid microelement-forming material includes a compound containing a hydrophobic group and a hydrophilic group. According to claim 19,
The material for forming the polymer matrix comprises a material formed by chemically bonding or mixing an isocyanate prepolymer and a hydrophilic compound in an amount of 1 to 20 parts by weight based on 100 parts by weight of the isocyanate prepolymer. According to claim 19,
The method of manufacturing a polishing pad, characterized in that the compound containing the hydrophobic group and the hydrophilic group is a compound formed by an ester reaction of a fatty acid and a hydrophilic compound. According to claim 21,
The method of manufacturing a polishing pad, characterized in that the fatty acid is any one selected from the group consisting of acetic acid, laurylic acid, oleic acid, palmitic acid, stearic acid, and linoleic acid, or a mixture thereof. According to claim 21,
The hydrophilic compound is composed of polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, and sorbitol fatty acid ester. Method for producing a polishing pad, characterized in that any one selected from the group or a mixture thereof.

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