KR101080572B1 - Polishing pad and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a polishing pad and a method of manufacturing the same. A polishing pad for performing a polishing process by moving in contact with a surface of an object to be polished according to the present invention, wherein the polishing pad comprises a polishing layer, and the polishing layer comprises a hydrophilic polymer matrix containing polyalkylene glycol ( Hereinafter referred to as a 'polyalkylene glycol-containing hydrophilic polymer matrix', and liquid microelements occupying a certain area within the polyalkylene glycol-containing hydrophilic polymer matrix, and the surface of the polishing layer has leaked liquid microelements. It is characterized in that the pores opened by the distribution.

Description

Polishing pad and manufacturing method thereof {POLISHING PAD AND MANUFACTURING METHOD THEREOF}

The present invention relates to a polishing pad and a method of manufacturing the same, and more particularly to a polishing pad having an improved surface properties and a method of manufacturing the same.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing pad and a method for manufacturing the same, and more particularly, to a polishing pad having a hydrophilic polymatrix and having an increased flatness.

Chemical mechanical planarization / chemical polishing (hereinafter referred to as CMP) process is a process introduced for global planarization of semiconductor devices, and it has a trend of large wafer size, high integration, finer line width, and multilayered wiring structure. As a result, it is emerging as a more important process.

The chemical mechanical polishing process (hereinafter referred to as CMP) is a process introduced for global planarization of semiconductor devices, and is becoming an important process according to the trend of large diameter, high integration, finer line width, and multilayered wiring structure.

Polishing speed and flatness are important in the CMP process, which are determined by the processing conditions of the polishing equipment and the polishing slurry and polishing pad, which are consumable members used. In particular, the polishing pad uniformly distributes the polishing slurry supplied in contact with the surface of the wafer on the wafer and causes physical removal 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 maintain the polishing slurry in a saturated state so that the polishing slurry flows smoothly. To this end, hollow polymeric microelements and micro hollow polymer bundles of cellular structures are incorporated into the polymer matrix to continuously collect fine pores that can collect and supply the polishing slurry on the polishing pad surface during the polishing process. Polishing pads to be formed are disclosed in US Pat. No. 5,578,362, Korean Patent Publication No. 2001-2696, Korean Patent Publication No. 2001-55971, and the like.

However, such a prior art has a problem in that the uniform collection and supply efficiency of the polishing slurry is inferior, so that the polishing target is uniformly polished by including spherical liquid microelements having a diameter of 5 to 60 μm in the polymer matrix of the polishing pad. Therefore, a technique has been proposed to perform a polishing process with high precision.

However, in order to exhibit the polishing efficiency over a certain level in the CMP process, not only the fine pores on the pad but also the roughness of the surface on the pad plays an important role. In the actual CMP process, a padding condition is performed by rubbing the pads with diamond discs before the CMP process, in order to activate the pads with high polishing surface roughness.

However, in most polishing pads, the polymer matrix is composed mainly of polytetramethylene glycol compound, which has the advantage of prolonging the life of the pad due to the excellent wear resistance of polytetramethylene glycol, but the roughness of the pad surface is not activated quickly. As a result, an initial pad stabilization time is required after the conditioning process in actual polishing process, which may act as a factor of lowering productivity and polishing performance.

US Pat. No. 6,641,471 also adds a separate process for activating the pad surface roughness during pad fabrication through shortening of the conditioning process time. This has the advantage that the roughness of the pad is activated early, but there is a disadvantage in that a separate operation for removing this due to the increase of the foreign matter on the pad as well as the increase in the manufacturing time and cost increase as the manufacturing process is increased.

Furthermore, when the spherical liquid microelements having a diameter of 5 to 60 µm are included in the polymer matrix of the polishing pad to enable uniform collection and supply of the polishing slurry, the liquid microelements are dispersed in the hydrophilic polymer matrix. Due to its properties, the pad life time is improved due to better wear resistance than a pad of a polymer matrix in which conventional polytetramethylene glycol is mainly used, but there is a problem in that the initial pad stabilization time required for the CMP process is further shortened. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to provide a polishing pad including a hydrophilic material to improve the precision during the polishing process and improving the flatness of the polishing layer and a method of manufacturing the same. .

In order to achieve the above object, a polishing pad performing a polishing process by moving in contact with a surface of an object to be polished according to the present invention, wherein the polishing pad includes a polishing layer, and the polishing layer is a polyalkylene glycol And a hydrophilic polymer matrix containing hereinafter (hereinafter referred to as a 'polyalkylene glycol-containing hydrophilic polymer matrix') and liquid microelements occupying a certain area in the polyalkylene glycol-containing hydrophilic polymer matrix. It characterized in that the pores are opened by the leakage of the liquid micro-elements are distributed.

In addition, in order to achieve the above object, the manufacturing method of the polishing pad according to the present invention comprises the steps of: mixing a hydrophilic material, a polyalkylene glycol compound and a liquid material to a material for forming a polymer matrix; Gelling and curing the resulting mixture to produce an abrasive layer with embedded liquid microelements; Processing the polishing layer to form a polishing pad on the surface of which pores opened by the leakage of the liquid microelements are distributed.

As described above, according to the present invention, the polishing pad is able to perform the polishing process with high precision due to the uniform collection and supply of the polishing slurry by the open pores of the microstructure, and continuously open during the polishing process. Since the pores are provided, the polishing performance is kept constant, and the composition of the pad is uniform at the polishing surface so that non-uniform wear of the pad does not occur so that the object to be polished can be uniformly polished.

Furthermore, since the surface of the polishing pad containing liquid microelements is composed of one component constituting the polymer matrix without high hardness components, the surface of the pad is uniformly worn and stable to use. Since there is no material and forms surface pores with a liquid material, there is no scratch generation of the wafer due to the micro element of the polymer material generated in the conventional pad, and the conventional powdery polymer because the liquid material is used in the manufacture of the polishing pad. The workability is superior to that of using the material.

In addition, by applying the hydrophilic polymer matrix, it is possible to uniformly mix the liquid material and the material for forming the polymer matrix without using a separate surfactant for dispersing the liquid material, there is no spillage of the liquid material during curing and pad manufacturing The reduction in the number of components required for the process can achieve cost savings due to the simplification of the manufacturing plant.

In addition, since the polyalkylene glycol component is included in the hydrophilic polymer mattress, the surface roughness which is advantageous for improving the polishing efficiency can be quickly formed, and the polishing rate can be improved as well as the pad stabilization time is shortened.

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

1 is a cross-sectional view of a polishing pad according to an embodiment of the present invention.

The polishing pad 100 according to the embodiment of the present invention as shown in the drawing is composed of a support layer 110 and the polishing layer 120. As shown in FIG. 2, the support layer 110 is a portion that allows the polishing pad 100 to adhere to the platen 3. The support layer 110 is made of a material having restorability in response to a force for pressing the silicon wafer 7 to be polished, which is loaded on the head 5 facing the platen 3, and the polishing layer 120 formed thereon. ) To support the silicon wafer 7 with a uniform elastic force. Therefore, it is mainly made of a non-porous solid uniform elastic material, the hardness is lower than the polishing layer 120 formed thereon.

In addition, at least a portion of the support layer 110 may be transparent or translucent to transmit the light beam 170 used to detect flatness of the surface to be polished. In FIG. 2, the wafer 7 on which a to-be-polished film is formed, such as a metal and an insulating layer, is illustrated as a target to be polished. Of course, it can be used as a target. In some cases, the polishing pad 100 may be configured without the support layer 110.

In addition, FIG. 2 illustrates a case in which the shape of the polishing pad 100 is circular so as to be suitable for the rotary polishing apparatus 1, but the shape of the polishing pad 100 may be modified in various shapes such as a rectangle and a square according to the shape of the polishing apparatus 1. Of course.

As shown in FIG. 2, the polishing layer 120 is a portion in direct contact with the wafer 7 to be polished. The polishing layer 120 has a predetermined region in the hydrophilic polymer matrix containing polyalkylene glycol (hereinafter referred to as 'polyalkylene glycol-containing hydrophilic polymer matrix') 130 and the polyalkylene glycol-containing hydrophilic polymer matrix 130. It is composed of a liquid microelement (hereinafter referred to as an embedded liquid microelement) 140 that is occupied and uniformly distributed. The polishing layer surface 160 in direct contact with the wafer 7 is uniformly arranged with a plurality of micropores 140 ′ defined and opened by the embedded liquid microelement 140.

Here, the pore 140 ′ is defined and opened by the embedded liquid microelement 140, and the liquid microelement 140 embedded in the polishing layer 120 leaks to the outside. This means that the region in which the 140 is included remains as the pores 140 ′ to capture certain substances from the outside.

Meanwhile, the polishing layer 120 forms a heterogeneous system composed of the polyalkylene glycol-containing hydrophilic polymer matrix 130 and the liquid microelements 140, whereby the polishing layer 120 is a silicon to be polished. It becomes translucent with respect to the light source 170 which can optically detect the surface state, ie flatness, of the wafer 7.

Therefore, the entire polishing pad 100 is composed of at least a portion of the transparent or semi-transparent support layer 110 and the entire semi-transparent polishing layer 120 and in-situ during the polishing process using the polishing pad 100. ), The flatness of the surface to be polished can be easily detected.

In addition, as the polishing pad 100 wears during the polishing process, the embedded liquid microelements 140 are continuously exposed to the polishing layer surface 160, which is replaced by the polishing slurry 13. Therefore, since only the polymer matrix is present on the polishing surface 160, the non-uniform wear of the polishing pad 100 does not occur and the silicon wafer 7 to be polished can be uniformly polished.

The polyalkylene glycol-containing hydrophilic polymer matrix 130 is preferably formed of a material that is 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 is formed of a material that cannot penetrate.

In addition, the polyalkylene glycol-containing hydrophilic polymer matrix 130 is preferably formed of a material capable of casting and extrusion.

For example, the polyalkylene glycol-containing hydrophilic polymer matrix 130 may be formed by chemical bonding or physical mixing between the polymer matrix forming material, the hydrophilic material, and the polyalkylene glycol compound.

The material of the polymer matrix produced by the material for forming the polymer matrix here is polyurethane, polyether, polyester, polysulfone, polyacryl, polycarbonate, polyethylene, polymethyl methacrylate, polyvinyl acetate, polyvinyl chloride, polyethylene It may correspond to any one selected from the group consisting of imines, polyether sulfones, polyether imides, polyketones, melamines, nylons and hydrocarbon fluorides or mixtures thereof.

Among these, the polymer matrix is preferably made of polyurethane. The polyurethane is obtained from a two-part, low viscosity liquid urethane consisting of an isocyanate prepolymer and a curing agent. Prepolymers encompass oligomers or monomers as precursors to the final polymer. Isocyanate prepolymers have an average of 2 or more isocyanate functional groups and have a content of 4 to 16% by weight of reactive isocyanates. Obtained by The isocyanate prepolymer reacts with a curing agent having an isocyanate reactive group to finally form a polyurethane. Here, as the curing agent, various polyols of amines such as 4, 4-methylene-bis (2-chloro aniline) (hereinafter MOCA) or polyether-based and polyester-based may be used. Polyurethane can control the physical properties by various combinations of components.

The polyalkylene glycol-containing hydrophilic polymer matrix 130 corresponds to a combination of a hydrophilic material and a polyalkylene glycol compound by a chemical method or a physical method in the polymer matrix.

Hydrophilic substances include polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkyl phenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, sorbitol fatty acid ester One selected from or a mixture thereof may be cited as an example.

The polyalkylene glycol compound may be any one selected from the group consisting of compounds in which alkylene oxide is added to a compound containing water or active hydrogen or a mixture thereof.

Here, the compound containing active hydrogen includes ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, butanediol, pentanediol, nucleic acid diol, decandiol, cyclonucleodiol diol, 3- Cyclonucleic acid-1,1-dimethanol, 4-methyl-3-cyclonucleic acid-1,1-dimethanol, 3-methylene-1,5-pentanediol, diethylene glycol, (2-hydrooxyethoxy) -1-propanol, 4- (2-hydrooxyethoxy) -1-butanol, 5- (2-hydroxypropoxy) -1-pantanol, 1- (2-hydroxymethoxy) -2-nucleic acid Ol, 1- (2-hydroxypropoxy) -2-octanol, 3-allyloxy-1,5-pentanediol, 2-allyloxymethyl-2-methyl-1,3-propanediol, glycerol , 1,2,6-nucleic acid triol, 1,1,1-trimethylolethane, 1,1,1, -trimethylolpropane, diethylene glycol, dipropylene glycol, panthaerythritol, sorbitol, sugar, lactose, Alphamethylglucoside, alphahydroxyglucoside, noblock resin, Phosphoric acid, benzenephosphoric acid, polyphosphoric acid, ethylenediamine, toluenediamine, diethylenetriamine, triethylenetetraamine, triethanolamine may be included at least any one, alkylene oxide is ethylene It may be one containing at least one of oxide, propylene oxide, butylene oxide.

The polyalkylene glycol compound preferably has a molecular weight of 200 to 10,000, and occupies a weight ratio of 1 to 50% based on the total weight of the polishing layer 120.

The plurality of pores 140 ′ and the embedded liquid unrequired element 140 arranged on the polishing layer surface 160 are intended to collect the polishing slurry 13 and to facilitate the supply to improve polishing uniformity. Thus, the pores 140 ′ of the polishing layer surface 160 and the embedded liquid microelements 140 are preferably uniformly distributed within the polyalkylene glycol-containing hydrophilic polymer matrix 130.

The embedded liquid microelement 140 is formed of a liquid material that is incompatible with the polyalkylene glycol-containing hydrophilic polymer matrix 130. The aliphatic mineral oil, aromatic mineral oil, silicone oil having no hydroxyl group at the molecular end, soybean oil, palm oil, palm oil , Cottonseed oil, camellia oil, hydrogenated oil, any one selected from the group consisting of or a mixture thereof may be used.

The embedded liquid microelement 140 is preferably formed by being dispersed in the polyalkylene glycol-containing hydrophilic polymer matrix 130 in a fine spherical shape. It is preferable that it is 1-30 micrometers, and, as for a spherical average diameter, it is more preferable that it is 2-10 micrometers. When the diameter of the sphere is in the above range, it is most suitable for the collection and supply of the polishing slurry 13. However, depending on the type of polishing slurry 13 used, the suitable spherical diameter may vary, and the size of the embedded liquid microelement 140 may also change accordingly.

The shape of the embedded liquid microelement 140, that is, the average diameter and the concentration of the spherical particles, is easily and variously controlled by changing the degree of hydrophilicity of the polyalkylene glycol-containing hydrophilic polymer matrix 130.

In addition, the shape of the embedded liquid microelement 140 is easily and variously controlled by the weight ratio of the liquid material. Preferably, the liquid material is mixed at 20 to 50% by weight, more preferably at 30 to 40% by weight, based on the total weight of the material for forming the polymer matrix, such as a polyurethane substrate, to produce the microelement in the desired form.

When the amount of the liquid material is 20% by weight or less, the size of the embedded liquid microelement 140 is increased, and as a result, the size of the pores 140 ′ formed on the pad surface 160 is increased. In this case, a large amount of particles of the polishing slurry 13 shows a relatively high polishing rate, but this makes it difficult to precisely polish the particles, and when the polishing slurry 13 contains non-uniformly large particles, large particles of the polishing slurry 13 Can be collected and scratch the wafer.

On the other hand, if the amount of the liquid material is more than 50% by weight, there is a disadvantage in that the pores 140 'of a large size are formed by coalescing between the microelements according to the increase in the concentration of the embedded liquid microelement 140.

That is, the size and concentration of the embedded liquid microelement 140 and the pores 140 ′ defined therein are variously controlled by the degree of hydrophilicity and / or the amount of the liquid material of the polyalkylene glycol-containing hydrophilic polymer matrix 130. Since this is possible, the polishing pad 100 having various polishing performances may be manufactured according to the type of the polishing target and / or the type of the polishing slurry 13.

The polishing layer surface 160 preferably further includes tissue or patterns including flow channels that facilitate the transfer of the polishing slurry 13.

Hereinafter, a process of manufacturing a polishing layer 120 of the polishing pad 100 according to an embodiment of the present invention will be described with reference to FIG. 3. The type of materials constituting the polishing layer 120 and the content ratio thereof are described above, and thus a detailed description thereof will be omitted.

First, materials for forming the polishing layer 120 are mixed (S100). Specifically, the liquid material is mixed with the polyalkylene glycol-containing hydrophilic polymer matrix 130 at a content ratio described above.

Here, the material for forming the polyalkylene glycol-containing hydrophilic polymer matrix 130 is a material produced by mixing a hydrophilic material and a polyalkylene glycol compound with the material for forming the polymer matrix.

Mixing preferably uses a dispersant to ensure that the liquid material is uniformly dispersed within the material for forming the polyalkylene glycol-containing hydrophilic polymer matrix 130. It is preferable to advance dispersion mixing by the stirring system.

Next, the gelation and curing reaction proceeds (S110). The mixture is injected into a mold of a predetermined shape to solidify through the gelation and curing process. The gelation reaction proceeds at 80 to 90 ° C. for 5 to 30 minutes, and the curing reaction is allowed to proceed at 80 to 120 ° C. for 20 to 24 hours. However, the specific process temperature and time may be variously changed to find the optimum conditions.

Finally, the resultant cured to a predetermined shape is processed (S120). Processing includes demolding, cutting, surface finishing and cleaning processes. First, the cured reactant is taken out of the mold and cut to have a predetermined thickness, shape and shape. It is a matter of course that the polishing layer 120 may be formed into a sheet by any method known in the art of polymer sheet manufacturing such as casting and extrusion molding to improve productivity. In addition, it is preferable to form various types of grooves 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.

Thereafter, the polishing layer 120 is completed through a washing process. During the cleaning process, the liquid microelements 140 of the polishing layer surface 160 are eluted to distribute pores 140 ′ open to the polishing layer surface 160. At this time, it is preferable to proceed with the cleaning process using a cleaning liquid so that the eluted liquid microelement 140 does not remain on the polishing layer surface 160.

Although the polishing pad 100 may be completed using only the polishing layer 120, if necessary, the support layer 110 may be manufactured by a method well known in the manufacturing process of the polishing pad 100, and the support layer 110 and the polishing layer ( 120 may be combined to complete the polishing pad 100.

More detailed information on the present invention will be described through comparison of the following specific experimental examples, and details not described herein will be omitted because those skilled in the art can sufficiently infer technically. Of course, the scope of the present invention is not limited by the following experimental examples.

First, a process generated according to the conventional method and a result generated by the process will be described with reference to <Experiment 1> and <Experiment 2> and FIG. 4.

Experimental Example 1

50 g of polytetramethylene glycol (molecular weight 1000), 50 g of polyethylene glycol (molecular weight 1000) and 52 g of toluene diisocyanate were added to a 2 l four-necked flask and reacted for 4 to 5 hours at a temperature of 70 to 80 ° C. It was set as%. The viscosity of the prepared isocyanate prepolymer was 6,900 cPs (25 ° C.).

Experimental Example 2

100 g of the isocyanate prepolymer of Experimental Example 1 and 46 g of mineral oil (hereinafter referred to as KF-70) (manufactured by Seojin Chemical Co., Ltd.) were uniformly mixed using a mechanical stirrer and left in a vacuum oven at 80 ° C. for 10 minutes to remove bubbles in the mixture. And the final temperature of the mixture was adjusted to 80 ° C. 33 g of MOCA, previously weighed and adjusted to 80 ° C., is poured into the mixture, mixed for 30 seconds at 3000 rpm using a mechanical stirrer, and immediately injected into a square mold. The injected reaction solution was gelled for 30 minutes and then cured in an oven at 100 ° C. for 20 hours. The prepared cured product was removed from the mold and the surface thereof was cut to prepare an abrasive layer 120 of the abrasive pad 100. After the prepared pad was polished for 10 minutes with a diamond disk, the surface roughness was Rp 30, Rv 25, and Rsm 230, and is shown in FIG. 4.

In FIG. 4A, the horizontal axis corresponds to the distance from the central axis of the polishing layer 120, and the vertical axis represents the height of the polishing layer surface 160. In FIG. 4B, the horizontal axis corresponds to the vertical axis of FIG. 4A, and the vertical axis of FIG. 4B corresponds to the number of irregularities corresponding to the height of each polishing layer surface 160.

Next, the process of generating the abrasive layer 120 and the resultant generated by the process according to an embodiment of the present invention will be described with reference to <Experiment 3> and <Experiment 4> and FIG. 5.

Experimental Example 3

65 g of polytetramethylene glycol (molecular weight 1000), 30 g of polypropylene glycol (molecular weight 1000), 5 g of polyethylene glycol (molecular weight 1000) and 53.7 g of toluene diisocyanate were added to a 2 l four-necked flask and 4 to 5 at a temperature of 70 to 80 ° C. After reacting for a time, the NCO content of the final product was 11.0%. The viscosity of the prepared isocyanate prepolymer was 6,600 cPs (25 ° C.).

Experimental Example 4

With the isocyanate prepolymer of Experimental Example 2, the polishing layer 120 of the polishing pad 100 was prepared in the same manner as in Experimental Example 2. After polishing for 10 minutes with a diamond disk in the same manner as in Experimental Example 6, the surface roughness was Rp 23, Rv 18, Rsm 180, it is shown in FIG.

FIG. 5 (a) corresponds to FIG. 4 (a) generated by the conventional method, and FIG. 5 (b) corresponds to FIG. 4 (b).

Comparing FIGS. 4 (a) and 5 (a), the surface roughness of the polishing layer 120 produced according to the present embodiment is advantageous to the polishing rate over the surface roughness of the polishing layer 120 produced by the conventional method. It can be seen that formed in the direction. That is, it can be seen that the surface roughness of the polishing layer 120 according to the present embodiment is formed with less variation and density.

This can be seen more clearly when comparing Fig. 4 (b) and Fig. 5 (b). In other words, the narrower the width on the graph, the smaller the surface unevenness is. Therefore, it can be seen that the polishing layer 120 according to the present embodiment can improve the polishing efficiency than the polishing layer 120 according to the conventional method. .

6 illustrates the effect of improving the polishing efficiency in more detail.

The figure shows the difference between the roughness of the polishing layer surface 160 and the number of polishing slurries 13 'reacting on the wafer.

That is, as the surface roughness of the polishing layer 120 contacting the wafer becomes rougher, the number of polishing slurries 13 'reacting on the wafer decreases (see FIG. 6 (a)), and the surface of the polishing layer 120 contacts the wafer. The higher the surface roughness, the greater the number of abrasive slurries 13 'reacting on the wafer (see Fig. 6 (b)).

As a result, it may be understood that the polishing efficiency may vary depending on the number of pores 140 ′ generated by the leakage of the liquid microelements 140 on the polishing layer surface 160 and the roughness of the polishing layer surface 160. .

Experimental Example 5

90 g of the isocyanate prepolymer of Experimental Example 3 and 46 g of KF-70 were mixed uniformly using a mechanical stirrer and left in a vacuum oven at 80 ° C. for 10 minutes to remove bubbles in the mixture, and the final temperature of the mixture was changed to 80 ° C. Adjusted. 10 g of polypropylene glycol (molecular weight 1000) was added to 30 g of MOCA previously weighed and adjusted to 80 ° C. to prepare a mixed solution, which was poured into the mixture and mixed at 3000 rpm for 30 seconds using a mechanical stirrer. Inject into the mold of. The injected reaction solution was gelled for 30 minutes and then cured in an oven at 100 ° C. for 20 hours. The prepared cured product was removed from the mold and the surface thereof was cut to prepare an abrasive layer 120 of the abrasive pad 100. An SEM image of the prepared abrasive layer 120 is shown in FIG. 7. It can be confirmed that there are open pores 140 'having an average diameter of about 10 to 20 μm on the surface of the polishing layer 160 of the manufactured pad, and the concentration of these pores 140' is 50 to 60 / 0.01 mm 2 degree was shown.

That is, the pores 140 ′ are exposed to the outside as the surface of the polishing layer 120 is polished, and thus the polishing slurry 13 may be collected and supplied.

As described above, the polishing pad 100 according to the exemplary embodiment of the present invention includes a hydrophilic polymer matrix containing polyalkylene glycol and liquid microelements 140 occupying a predetermined region in the hydrophilic polymer matrix. The polishing efficiency is improved by collecting and supplying the polishing slurry 13 of the pores 140 'according to the external exposure of the uniform liquid microelements 140, and the polishing pad 100 (i.e., the polishing layer 120) The roughness of the surface is evenly made by the conditioning process, and by the surface of which the roughness of the polishing pad 100 is even, the amount of polishing slurry 13 ′ reacting to the abrasive such as a wafer can be increased to further increase the polishing efficiency. That is, the work time can be shortened and the polishing efficiency can be increased.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. It is to be understood that such variations and modifications are intended to be included in the scope of the appended claims.

1 is a cross-sectional view of a polishing pad using a hydrophilic polymer matrix containing a polyalkylene glycol according to an embodiment of the present invention,

2 is a schematic view of a polishing apparatus equipped with the polishing pad of FIG. 1,

Figure 3 is a flow chart of the manufacturing process of the polishing layer of the polishing pad according to an embodiment of the present invention,

4 is a view showing the surface roughness of the polishing layer according to the conventional method (Experimental Example 1, Experimental Example 2),

5 is a view showing the surface roughness of the polishing layer according to the method (Experimental Example 3, Experimental Example 4) according to the present invention,

FIG. 6 is a view for explaining the amount of polishing slurry reacting to the polished material according to the surface roughness of the polishing layer.

7 is a SEM photograph of the polishing pad expression by the method (Experimental Example 5) according to the present invention.

* Explanation of symbols for the main parts of the drawings

1: polishing device 3: platen

5: head 7: silicon wafer

11: nozzle 13: polishing slurry

100: polishing pad 110: support layer

120 abrasive layer 130 polyalkylene glycol-containing hydrophilic polymer matrix 140 liquid microelement

140 ': pore 160: surface of abrasive layer

170: light beam

Claims (21)

A polishing pad for performing a polishing process by moving in contact with a surface to be polished, The polishing pad includes a polishing layer, The polishing layer includes a hydrophilic polymer matrix containing polyalkylene glycol (hereinafter referred to as a 'polyalkylene glycol-containing hydrophilic polymer matrix') and liquid microelements that occupy a certain area in the polyalkylene glycol-containing hydrophilic polymer matrix. Is composed by And polishing pores distributed on the surface of the polishing layer by leakage of the liquid microelements. The method of claim 1, The polyalkylene glycol-containing hydrophilic polymer matrix is a polishing pad, characterized in that formed by the chemical bonding or physical mixing between the polymer matrix-forming material, the hydrophilic material and the polyalkylene glycol compound. 3. The method of claim 2, The polyalkylene glycol compound is a polishing pad, characterized in that configured to have a molecular weight of 200 ~ 10,000. 3. The method of claim 2, The polyalkylene glycol compound is a polishing pad, characterized in that accounting for 1 to 50% by weight of the total weight of the polishing layer. 3. The method of claim 2, The polyalkylene glycol compound is a polishing pad, characterized in that any one or a mixture thereof selected from the group consisting of compounds in which alkylene oxide is added to a compound containing water or active hydrogen. The method of claim 5, Examples of the compound containing active hydrogen include ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, butanediol, pentanediol, nucleic acid diol, decandiol, cyclonucleodiol diol, and 3-cyclo Nucleic acid-1,1-dimethanol, 4-methyl-3-cyclonucleic acid-1,1-dimethanol, 3-methylene-1,5-pentanediol, diethylene glycol, (2-hydrooxyethoxy)- 1-propanol, 4- (2-hydrooxyethoxy) -1-butanol, 5- (2-hydrooxypropoxy) -1-pantanol, 1- (2-hydroxymethoxy) -2-nucleool 1- (2-hydroxypropoxy) -2-octanol, 3-allyloxy-1,5-pentanediol, 2-allyloxymethyl-2-methyl-1,3-propanediol, glycerol, 1,2,6-nucleic acid triol, 1,1,1-trimethylolethane, 1,1,1, -trimethylolpropane, diethylene glycol, dipropylene glycol, panthaerythritol, sorbitol, sugar, lactose, alpha Methylglucoside, Alphahydroxyglucoside, Noblock Resin, Pho A polishing pad comprising at least one of sporic acid, benzenephosphoric acid, polyphosphoric acid, ethylenediamine, toluenediamine, diethylenetriamine, triethylenetetraamine, and triethanolamine. The method of claim 5, The alkylene oxide is a polishing pad comprising at least one of ethylene oxide, propylene oxide, butylene oxide. 3. The method of claim 2, The hydrophilic material is a group consisting of polyethylene glycol, polyethylene propylene glycol, polyoxyethylene alkyl phenol ether, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, polyoxyethylene alkylamine ether, glycerin fatty acid ester, sugar fatty acid ester, sorbitol fatty acid ester Polishing pad, characterized in that any one or a mixture thereof. The method of claim 8, Wherein said hydrophilic polymer matrix comprises said hydrophilic material in a weight ratio of 1 to 20% relative to the total weight of the isocyanate prepolymer. The method of claim 1, And the liquid microelements are spherical in shape and have an average diameter of 1 to 100 um and are uniformly distributed in the hydrophilic polymer matrix. delete The method of claim 1, And the liquid microelements are included in a weight ratio of 10 to 60% relative to the total weight of the material for forming the polymer matrix. The method of claim 1, The liquid microelements are any one or a mixture thereof selected from the group consisting of aliphatic mineral oil, aromatic mineral oil, silicone oil having no hydroxyl group at the molecular end, soybean oil, palm oil, palm oil, cottonseed oil, camellia oil and hardened oil. The method of claim 1, The polishing pad, characterized in that the surface of the polishing layer is further formed with a tissue or pattern including a flow channel to facilitate the transport of the polishing slurry. The polishing pad according to claim 1, wherein the polishing layer is translucent to a light source for detecting a state of the surface to be polished. (a) mixing a hydrophilic material, a polyalkylene glycol compound, and a liquid material with a material for forming a polymer matrix; (b) gelling and curing the mixture produced in step (a) to produce an abrasive layer with embedded liquid microelements; (c) processing the polishing layer to form a polishing pad in which pores opened by leakage of the liquid microelements are formed on a surface thereof. The method of claim 16, The step (a) further comprises the step of producing a polyalkylene glycol compound having a molecular weight of 200 ~ 10,000. The method of claim 16, The method of claim 1, wherein the polyalkylene glycol compound is mixed in an amount of 1 to 50% by weight based on the total weight of the polishing layer. The method of claim 16, The step (a) further comprises the step of producing a polyalkylene glycol compound by mixing any one or selected from the group consisting of a compound in the form of alkylene oxide is added to a compound containing water or active hydrogen Method for producing a polishing pad. The method of claim 19, Examples of the compound containing active hydrogen include ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, butanediol, pentanediol, nucleic acid diol, decandiol, cyclonucleodiol diol, and 3-cyclo Nucleic acid-1,1-dimethanol, 4-methyl-3-cyclonucleic acid-1,1-dimethanol, 3-methylene-1,5-pentanediol, diethylene glycol, (2-hydrooxyethoxy)- 1-propanol, 4- (2-hydrooxyethoxy) -1-butanol, 5- (2-hydrooxypropoxy) -1-pantanol, 1- (2-hydroxymethoxy) -2-nucleool 1- (2-hydroxypropoxy) -2-octanol, 3-allyloxy-1,5-pentanediol, 2-allyloxymethyl-2-methyl-1,3-propanediol, glycerol, 1,2,6-nucleic acid triol, 1,1,1-trimethylolethane, 1,1,1, -trimethylolpropane, diethylene glycol, dipropylene glycol, panthaerythritol, sorbitol, sugar, lactose, alpha Methyl glucoside, alpha hydroxyglucoside, noblock resin, po Preparation of a polishing pad, characterized in that at least any one of poric acid, benzenephosphoric acid, polyphosphoric acid, ethylenediamine, toluenediamine, diethylenetriamine, triethylenetetraamine, triethanolamine is included Way. The method of claim 19, The alkylene oxide is a method for producing a polishing pad, characterized in that it comprises at least one of ethylene oxide, propylene oxide, butylene oxide.

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