TWI466930B - Method for manufacturing porous sheet and porous sheet manufactured by the method - Google Patents

Description

Method for producing porous plate and porous plate prepared by using same

The present invention relates to a method for preparing a multi-well plate using supercritical fluid extraction (SFE), and a porous plate obtained by the method.

The present application claims priority to Korean Patent Application No. 10-2009-0051, 598, filed on Jan. 10, 2009, the entire disclosure of which is hereby incorporated by reference.

Chemical mechanical polishing (CMP) processes are used in the fabrication of microelectronic devices to form flat surfaces on semiconductor wafers, field emission displays, and many other microelectronic substrates. For example, the fabrication of semiconductor devices typically involves the formation of various process layers, the selective removal or patterning of such layers, and the deposition of additional process layers on the surface of a semi-conductive substrate to form a semiconductor crystal. circle. The process layer can include, for example, an insulating layer, a gate oxide layer, a conductive layer, and a metal or glass layer. It is generally desirable that the surface of the uppermost layer of the process layer is preferably flat in a particular step of the wafer process, i.e., flat for deposition of subsequent layers.

A chemical mechanical polishing (CMP) process is used to planarize the process layer, wherein a deposition material (eg, a conductive or insulating material) is ground and removed to planarize the wafer for subsequent processing steps.

In a typical chemical mechanical polishing (CMP) process, a wafer is inverted onto a carrier in a CMP apparatus. The carrier is pushed forward and the wafer is directed downward toward a polishing pad. The carrier and the wafer are rotated on a rotating polishing pad on a polishing table of a CMP apparatus. A polishing composition (also referred to as a polishing slurry) is typically introduced between the rotating wafer and the rotating polishing pad during the polishing process. The abrasive composition typically comprises: an abrasive material that can interact with or dissolve a portion of the uppermost wafer layer, and a portion that physically removes the layer. The wafer and the polishing pad can be rotated in the same direction or in opposite directions, whichever is appropriate for the particular polishing process being performed. The carrier can also oscillate between the polishing pads on the grinding table.

The polishing pad used in the chemical mechanical polishing (CMP) process is manufactured using both soft and rigid mats, including: polymer-impregnated fabrics, microporous films, porous polymers. Cellular polymer foams, non-porous polymer sheets, and sintered thermoplastic particles.

A pad comprising a polyurethane resin impregnated into a polyester nonwoven fabric can be said to be a polymer-impregnated fabric polishing pad. The microporous polishing pad comprises a microporous urethane film coated on a substrate material. Such a polishing pad is a hermetic, porous film. The porous polymer foam polishing pad comprises a hermetic structure that is randomly and evenly distributed in all three-dimensional spaces.

Recently, in most of the polishing pads, a perforated plate having closed-pores is used on the pad, wherein the hole controls the fluidity of the slurry to improve process efficiency. Therefore, it is important to uniformly disperse the holes in the polishing pad.

An example of a method of producing a polishing pad is as described in Korean Patent No. 10-0191227, by adding hollow polymeric microelements to a polymeric matrix.

However, the hollow polymerizable micro-elements have a casing having a thickness of several micrometers, and it is problematic that such a casing will be scraped on an object to be polished (for example, a wafer during a chemical mechanical polishing (CMP) process). mark.

An object of the present invention is to provide a method for producing a porous plate, wherein a hole having excellent uniformity and dispersibility is formed, a generation of scratches during a process is reduced, and process efficiency is improved, and a method obtained by using the method is provided. Multiwell plate.

The present invention provides a method of making a multi-well plate comprising the steps of a) fabricating a polymer resin sheet comprising one of an object treated by supercritical fluid extraction dissolved in a supercritical fluid; and b) injecting the supercritical fluid into the The polymer resin sheet extracts the object subjected to supercritical fluid extraction treatment in the polymer resin sheet, thereby forming voids in the polymer resin sheet.

The present invention provides a porous plate produced in accordance with the manufacturing method of the present invention.

The present invention provides a polishing pad comprising one of the perforated plates of the present invention.

According to the present invention, there is provided a method of producing a perforated plate capable of forming pores having excellent uniformity and dispersibility in a sheet. In addition, holes can be formed without leaving a residue in the plate because the method is carried out by extracting a material dissolved in one of the supercritical fluids. Therefore, during the polishing process, scratches generated on a polishing object (wafer) due to residues can be reduced, and process efficiency can be improved.

A method of making a multi-well plate according to the present invention, comprising the steps of a) producing a polymer resin sheet comprising one of an object via a supercritical fluid boundary extraction process dissolved in a supercritical fluid; and b) injecting the supercritical fluid into the A polymer resin sheet for extracting the object subjected to supercritical fluid extraction treatment in a polymer resin sheet, thereby forming pores in the polymer resin sheet.

In the step a), the object subjected to supercritical fluid extraction treatment may be selected from the group consisting of: an aromatic compound, an aliphatic hydrocarbon, and a material of an aliphatic alcohol.

Here, examples of the aromatic compound may include naphthalene, anthracene, 1,2-benzophene, and pentacene. The aliphatic hydrocarbon may be a C ₇ to C ₁₀ aliphatic hydrocarbon, but is not limited thereto, and specific examples thereof may include mineral oil, octane, decane, and dodecane. Examples of the aliphatic alcohol may include heptanol, decyl alcohol, and dodecyl alcohol.

Among them, it is preferred that the object treated by supercritical fluid extraction may be naphthalene or octane, but is not limited thereto.

The object contained in the polymer resin sheet subjected to supercritical fluid extraction treatment may be round or oval, but is not limited thereto.

In the step a), the object treated by the supercritical fluid extraction may be contained in the polymer resin sheet in an amount of 5 to 50% by weight, and more preferably 20 to 40% by weight.

The polymer resin sheet of step a) may comprise a polymer resin selected from the group consisting of: polyurethane, thermoplastic elastomer, polyolefin, polycarbonate, polyvinyl alcohol, nylon, elastomer rubber, styrene Base copolymer, polyaromatic compound, fluoropolymer, polyimine, crosslinked polyurethane, crosslinked polyolefin, polyether, polyester, polyacrylate, elastomer polyethylene, polytetrafluoroethylene , polyethylene terephthalate, polyarylene, polystyrene, polymethylmethacrylate, copolymers thereof, block copolymers thereof, mixtures thereof, And a group of blends thereof. Here, the polyurethane resin is an optimum material for forming the polishing pad because of its excellent abrasion resistance. Further, a polyurethane resin having one of desired physical properties can be easily obtained by changing its raw material composition. Such properties of the polyurethane resin are suitable for forming the polishing pad.

Step a) may comprise the step a1) mixing the mixture of the supercritical fluid extraction treated with a polymer resin or a precursor, and a2) the hardening step a1).

In step a1), the mixed environment of the object and the polymer resin or precursor subjected to supercritical fluid extraction may vary depending on the impeller speed and the reactor temperature in a reactor. In addition, a hardener can be used simultaneously during the mixing process. Here, the impeller speed and the reactor temperature can be individually controlled, but a preferred impeller speed can be 200 to 3000 rpm and a preferred reactor temperature can be 40 to 70 °C.

In the step a1), one or more chain extenders may be further added, which are selected from the group consisting of: 1,4-butanediol, 4,4'-methylenebis(2-chloroaniline), ethylene glycol, 1, 2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 2,2,4-trimethylpentanediol, hydroquinone, bis(2-hydroxyethyl)hydroquinone, 4,4'-dihydroxybiphenyl, bisphenol A, bisphenol F, and mixtures thereof Group.

In step a2), the hardening process can be carried out at 70 to 100 ° C for 4 to 48 hours.

In the step a), in the case of using a polyurethane resin to produce a sheet, the polyurethane may be elongated from an organic polyisocyanate, a polyurethane prepolymer, a polyalcohol compound and a chain. Prepared by the agent.

Herein, it may include: 1 to 20% by weight of organic polyisocyanate, 10 to 88% by weight of polyurethane prepolymer, 10 to 88% by weight of polyol compound and 1 to 50% by weight of chain extender .

Examples of the organic polyisocyanate may include: an aromatic diisocyanate (e.g., 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2, 2'2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate (4 , 4'-diphenylmethane diisocyanate), 1,5-naphthalene diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate, and M-xylylene diisocyanate; aliphatic diisocyanates (eg ethylenediisocyanate, 2,2,4-diisocyanate trimethylhexa) Methyl (2,2,4-trimethylhexamethylene diisocyanate) and 1,6-hexamethylene diisocyanate); and cycloaliphatic diisocyanates (eg 1, 4-cyclohexane diisocyanate e), 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, hydrogenated m-xylylene diisocyanate, and hail Norbornane diisocyanate. A mixture of one or two or more kinds thereof may be used. However, the organic polyisocyanate is not limited thereto.

The organic polyisocyanate contains not only the above-mentioned diisocyanate compound but also a polyfunctional (trifunctional or more) polyisocyanate compound. As the polyfunctional isocyanate compound, a series of diisocyanate adduct compounds of Desmodule-N (manufactured by Bayer Ltd.) or under the trade name of Duranat (Asahi Kasei Corporation) are commercially available.

The polyol compound is exemplified by high molecular weight polyalcohols (eg, polyether polyols, polyester polyols, polycarbonate polyols, and acryl polyols. In addition to high molecular weight polyols, low molecular weight polyols are also used. Such a polyol compound may be used in a mixture of two or more kinds. However, the polyol compound is not limited thereto.

The ratio of the organic polyisocyanate, the polyol compound, and the chain extender varies depending on the molecular weight of each compound or the use and desired properties of the polyurethane produced by such a compound (e.g., a polishing pad). In order to obtain a polishing pad having one of the desired abrasive properties, the number of isocyanates of the organic polyisocyanate may preferably range from 0.95 to the total number of functional groups of the polyol compound and the chain extender (the number of activated hydrogen groups of the hydroxyl group, the amine group, etc.). To 1.15, and more preferably from 0.99 to 1.10. Meanwhile, the ratio of the high molecular weight component to the low molecular weight component in the polyhydric alcohol compound can be determined by the desired properties of the polyurethane to which it is produced.

In the step a), in the case of using a polyurethane resin to produce a sheet, the matrix-based polyurethane resin can be applied by an urethane technique (for example, a melt method, a solution method or the like). ) made. In view of cost and operating environment, the melting method is preferred.

Any one of the one-shot and prepolymer methods can be applied to the manufacture of polyurethanes. However, in terms of the physical properties of the obtained polyurethane, a prepolymer method in which an isocyanate terminal prepolymer of one of an organic polyisocyanate and a polyol compound is synthesized in advance and a chain extender is This reaction.

Also, if it is suitable for the present invention, and can also be used in the production of polyurethanes by a prepolymer process, any commercially available isocyanate end made from organic polyisocyanates and polyalcohol compounds can be used. Prepolymer. Isocyanate terminal prepolymers having a molecular weight of from about 800 to 5,000 are suitable in terms of processibility and physical properties.

In the prepolymer process, the isocyanate terminal prepolymer is a compound containing an isocyanate group, and the chain extender (polyalcohol compound if necessary) is a compound containing an activated hydrogen group. In the one-shot process, the organic polyisocyanate is a compound containing an isocyanate group, and the chain extender and the polyalcohol compound are a compound containing an activated hydrogen group.

In the manufacture of polyurethanes, stabilizers (such as antioxidants, surfactants, lubricants, pigments, fillers, antistatic agents, and other additives) can be added to the polyurethane storage solution, if desired.

In the step b), the method of injecting the supercritical fluid into the polymer resin sheet produced in the step a) can be carried out by including a pressurized gas jet using a high pressure to advance the supercritical fluid into the polymer resin sheet. Implemented by the process.

The injection of the supercritical fluid in step b) into the polymer resin sheet will be described in detail.

Herein, the supercritical fluid refers to a material which has the characteristics of both liquid and gas at normal temperature and pressure, and is at a critical state higher than the supercritical point, that is, one of the liquids at a high temperature and a high pressure cannot be distinguished. The gas is called a supercritical point because a chemical can no longer be evaporated.

The supercritical flow system is produced by increasing the temperature and pressure of the gas, which is sufficient to maintain the fluid in a supercritical state.

The gas can be a hydrocarbon, a chlorofluorocarbon, a hydrochlorofluorocarbon (e.g., chlorofluorocarbon), nitrogen, carbon dioxide, carbon monoxide, or a combination thereof.

Preferred gases are non-flammable gases, such as gases without C-H bonds. More preferably, the gas is nitrogen, carbon dioxide or a combination thereof. More preferably, the gas is carbon dioxide or a gas containing carbon dioxide.

It is preferred to convert the gas into a supercritical gas before injecting the polymer resin sheet.

If the gas is carbon dioxide, the temperature exceeds 31 ° C and the pressure ranges from 7 MPa (about 1000 psi) to 35 MPa (about 5000 psi) (eg, 19 MPa (about 2800 psi) to 26 MPa (about 3800 psi)).

The supercritical fluid of step b) may preferably comprise one or more selected from the group consisting of supercritical carbon dioxide, supercritical isobutane, supercritical butane, supercritical propane, supercritical pentane, and supercritical nitrogen.

Step b) is carried out at a pressure of one of 50 to 300 atm and a temperature of 25 to 120 ° C, and preferably at a pressure of one of 70 to 200 atm and a temperature of 30 to 80 ° C. Step b) is one of the supercritical device implementations known in the art.

In step b), a supercritical fluid extraction method can be carried out by mixing with acetone, an alcohol or the like.

Here, when the supercritical fluid is injected, the solvent may be simultaneously added, or the solvent may be previously placed in a supercritical reactor, followed by a mixing process. The solvent may vary depending on the object comprising the polymeric resin sheet treated by supercritical fluid extraction. For example, acetone, alcohol or hexane is a material that dissolves the object treated by supercritical fluid extraction well.

Specifically, when the supercritical fluid of step b) is injected into the polymer resin sheet produced in step a), the supercritical fluid dissolves the object contained in the polymer resin sheet subjected to supercritical fluid extraction, thus in step a A hole is formed in the manufactured polymer resin sheet without residue. Here, the formed hole may be a closed hole, wherein the closed hole refers to a hole that is not connected to one of the other holes.

In the step b), the pores formed in the polymer resin sheet may be round or oval, but are not limited thereto.

In the step b), the pores formed in the polymer resin sheet may have an average diameter of 80 μm or less, preferably 5 to 50 μm, and more preferably 10 to 30 μm. Here, the average diameter of the holes is an average of the lines passing through the center of the circle.

In the step b), the plate having the pores formed therein may have a density of 0.5 to 1 g/cm ³ , preferably 0.6 to 1 g/cm ³ , more preferably 0.7 to 0.9 g/cm ^{3 .} .

In the step b), the sheet having the pores formed therein may have a porosity of 50% or less, preferably 10 to 50%, more preferably 20 to 40. One of the porosity.

Specifically, according to the present invention, the pores can be formed in the polymer resin sheet without residue (see Fig. 2). However, in the known high pressure gas foaming method, when the foaming process is carried out by injection into the hardened (i.e., crosslinked) polyurethane, there is a problem that the degree of hardening may not be due to the degree of hardening. produce. In polyurethanes that do not crosslink or have a low coefficient, the foaming is produced via pressurized gas jet, but in practice, it does not exhibit properties suitable for CMP mats. When the foaming process is carried out by a pressurized gas method with a polyurethane having a high degree of hardening, foaming does not occur, or the polymerizable matrix can be destroyed (see Fig. 4).

Meanwhile, the present invention provides a porous plate manufactured by the above method.

The perforated plate of the present invention can be used as a polishing pad. The perforated plate can be used as a polishing pad, and the singular and plural porous plate stacks are combined for use as a polishing pad. Further, other films attached to the perforated plate can be used as a polishing pad.

Hereinafter, the present invention will be described in detail in conjunction with FIG.

As shown in Fig. 1, the prepolymer of the polyurethane is mixed with the aliphatic hydrocarbon, naphthalene or fish oil dissolved in the supercritical fluid and well dispersed. This prepolymer mixed solution is reacted with 1,4-butanediol or 4,4'-methylenebis(2-chloroaniline) as a chain extender to form a polymer chain. The composition was hardened in an oven at 100 ° C for 4 hours to 6 hours and formed into a desired shape through a mold. The hardened polyurethane is placed in a supercritical device to extract a solute. Here, CO ₂ can be used as a supercritical fluid, and supercritical fluid extraction can be carried out by mixing with acetone or an alcohol. Specifically, a material such as acetone or an alcohol is placed in a polyurethane plate to be simultaneously extracted. That is, a suitable amount of acetone, alcohol or supercritical fluid extraction apparatus is placed, followed by closing the supercritical fluid extraction equipment, followed by injection of a desired CO ₂ pressure. Alternatively, simultaneously inject CO ₂ into the supercritical device.

[Example of invention]

Hereinafter, the present invention will be described in more detail with examples.

Example 1

In Example 1, the prepolymer and octane were first mixed with each other to prepare a mixed solution. L325 (manufactured by Chemtura, NCO% 9.17%) is used as a prepolymer, and octane is used as an object treated by supercritical fluid extraction (dissolved in a supercritical fluid), ie, as a porogen .

First, 1000 g of prepolymer and 400 g of octane were placed in a 50 ° C reactor and mixed with each other for 5 minutes. In this case, octane is dispersed in the prepolymer to form a spherical droplet in the prepolymer. Thereafter, MOCA (methylenebis(2-chloroaniline), methylenebis (2-chloroaniline)) was added thereto, followed by mixing. The prepared polyurethane mixture was poured into a mold and gelled at room temperature for 1 hour, followed by oven hardening at 100 ° C for 24 hours.

The hardened polyurethane mixture was cut at a thickness of 3 mm and placed in a supercritical fluid extraction apparatus. The temperature of the supercritical fluid extraction apparatus was set at 45 ° C, and carbon dioxide was pressurized into the apparatus, and the pressure was maintained at 150 bar. The mixture was maintained in the apparatus for 1 hour followed by reduced pressure. The polyurethane sample was taken out of the apparatus, left at room temperature for 1 hour, and then placed in a 100 ° C oven for 1 hour.

The prepared sample had a density of 0.802 g/cm ³ and a hardness of 50 Shore D. A SEM photograph of this sample is shown in Figure 2. The storage modulus and tan delta of the sample are shown in Figure 3.

Specifically, when a porous plate is produced by supercritical fluid extraction (SFE) according to the present invention, pores can be formed without leaving a residue in the plate because the method is dissolved in the supercritical fluid by extraction. Implemented as one of the materials. Therefore, the generation of scratches on an abrasive object due to the residue of the board during the polishing process can be reduced, and the process efficiency can be improved.

Example 2

In Example 2, the prepolymer and MOCA were first mixed, followed by mixing with octane.

First, L325 (manufactured by Chemtura, NCO% 9.17%) 1000 g as a prepolymer was placed in a reactor, and the temperature was maintained at 50 °C. The previously dissolved MOCA 260 g was placed and mixed at 1000 rpm for 30 seconds, followed by mixing octane 400 g with it.

The prepared polyurethane mixture was poured into a mold and gelled at room temperature for 30 minutes, followed by oven hardening at 100 ° C for 16 hours.

The hardened polyurethane mixture was cut at a thickness of 3 mm and placed in a supercritical fluid extraction apparatus. The temperature of the supercritical fluid extraction apparatus was set at 40 ° C, and carbon dioxide was pressurized into the apparatus, and the pressure was maintained at 100 bar. The mixture was maintained in the apparatus for 2 hours, followed by reduced pressure. The polyurethane sample was taken out of the apparatus, left at room temperature for 1 hour, and then placed in a 100 ° C oven for 1 hour.

Example 3

In Example 3, in order to manufacture a pad having a high modulus, H ₁₂ MDI was added.

The experiment was carried out in the same manner as in Example 1, except that H ₁₂ MDI was added to L325 to prepare a prepolymer having an NCO % of 9.7%. The storage modulus and tan delta of the mat produced in Example 3 are shown in Fig. 3.

Example 4

In Example 4, in order to manufacture a pad having a high modulus, H ₁₂ MDI was added.

The experiment was carried out in the same manner as in Example 1, except that H ₁₂ MDI was added to L325 to prepare a NCO% 11% prepolymer. The storage modulus and tan delta of the mat produced in Example 4 are shown in Fig. 3.

Example 5

In Example 5, in order to manufacture a pad having a high modulus, H ₁₂ MDI was added.

The experiment was carried out in the same manner as in Example 1, except that H ₁₂ MDI was added to L325 to prepare a NCO% 12% prepolymer. The storage modulus and tan delta of the pad produced in Example 5 are shown in Fig. 3.

Example 6

First, 1000 g of prepolymer and 300 g of octane were placed in a 50 ° C reactor and mixed with each other for 2 minutes. In this case, octane and dodecane are dispersed in the prepolymer to form spherical droplets (1 to 100 microns) in the prepolymer. Thereafter, MOCA (methylenebis(2-chloroaniline), methylenebis (2-chloroaniline)) was added thereto, followed by mixing. The prepared polyurethane mixture was poured into a mold and gelled at room temperature for 1 hour, followed by oven hardening at 100 ° C for 24 hours. After the hardening process, the experiment was carried out in the same manner as in Example 1. The holes of the resulting mat have a diameter of one of 10 to 70 microns.

Example 7

The hardened backing sheet was placed in the supercritical fluid extraction apparatus in the same manner as in Example 1. The temperature and pressure were maintained at 50 ° C and 150 bar, respectively. After 1 hour, the pressure was removed, and the plate removed, and the CO ₂ is removed from the oven at 100 deg.] C completely. The resulting pad had a density of 0.75 g/cm ³ .

The experimental results (storage modulus and tan delta) of Example 1 and Examples 3 to 5 are shown in Figure 3, and the storage modulus and tan delta measurement method of Figure 3 will be detailed. Narrative. The storage modulus and the tan delta were measured using a DMA8000 (manufactured by PerkinElmer) at a frequency of 1.5 Hz and an amplitude of 0.05 mm, and scanned at a temperature of -10 ° C to 100 ° C.

As shown in Fig. 3, the storage modulus and the tan delta of the sample (NCO% 9.17%) prepared in Example 1 were 396.5 MPa at 25 °C.

The storage modulus of the sample, which was increased by the addition of H ₁₂ MDI with NCO% to 9.7, 11 or 12%, was 446.8, 580.3, 698.4 MPa, respectively, indicating that an increase in NCO% improved the storage modulus.

Meanwhile, as shown in FIG. 3, the tan delta tendency tends to decrease as the storage modulus increases.

Control case

First, 1000 g of L325 (manufactured by Chemtura, NCO% 9.17%) 1000 g as a prepolymer was placed in a 50 ° C reactor and mixed for 5 minutes. Thereafter, MOCA (methylenebis(2-chloroaniline)), 260 g of methylenebis (2-chloroaniline) was added thereto, followed by mixing. The prepared polyurethane mixture was poured into a mold and gelled at room temperature for 1 hour, followed by oven hardening at 100 ° C for 24 hours.

The hardened polyurethane mixture was cut at a thickness of 3 mm and placed in a supercritical foaming apparatus. The temperature of the supercritical foaming apparatus was set at 45 ° C, and carbon dioxide was pressurized into the apparatus, and the pressure was maintained at 150 bar. The mixture was maintained in the apparatus for one hour and then depressurized. The polyurethane sample was taken out of the apparatus, left at room temperature for 1 hour, and then placed in a 100 ° C oven for 1 hour.

An SEM photograph of one of the plates according to the comparative example was obtained. Therefore, cracks were found, as shown in FIG. The results show that once the polyurethane having a high degree of hardening is foamed by the pressurized gas method, the polymerizable matrix is destroyed as shown in FIG.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a diagram depicting a method of making a multi-well plate in accordance with the present invention.

Figure 2 is a SEM photograph of one of the perforated plates according to Example 1 of the present invention.

Fig. 3 is a graph showing the experimental results of Example 1 and Examples 3 to 5.

Figure 4 is a SEM photograph of one of the perforated plates according to the comparative example.

(The figure is a flow chart, so there is no component symbol)

Claims (13)

A method of making a multi-well plate comprising the steps of: a) fabricating a polymer resin sheet comprising one of an object treated by supercritical fluid extraction dissolved in a supercritical fluid; and b) injecting the supercritical fluid into the polymer a resin sheet for extracting the object subjected to supercritical fluid extraction treatment in the polymer resin sheet, thereby forming a void in the polymer resin sheet, wherein the object subjected to supercritical fluid extraction treatment comprises an aromatic selected from: One or more of a compound, an aliphatic hydrocarbon, and an aliphatic alcohol. The method of claim 1, wherein the polymer resin sheet of step a) comprises a polymer resin selected from the group consisting of polyurethane, thermoplastic elastomer, polyolefin, polycarbonate, Polyvinyl alcohol, nylon, elastomer rubber, styrene-based copolymer, polyaromatic compound, fluoropolymer, polyimine, cross-linked polyurethane, cross-linked polyolefin, polyether, polyester, poly Acrylate, elastomeric polyethylene, polytetrafluoroethylene, polyethylene terephthalate, polyarylene, polystyrene, polymethylmethacrylate, A group of copolymers, block copolymers thereof, mixtures thereof, and blends thereof. The method of claim 1, wherein the step a) comprises: step a1) mixing the object treated by supercritical fluid extraction with a polymer resin or a precursor; and a2) a mixture of the hardening step a1) . The method of claim 3, wherein in step a1), one or more chain extenders are further added, which are selected from the group consisting of: 1,4-butanediol, 4,4'-methylenebis(2-chloroaniline), ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,6-hexanediol, neopenta Glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 2,2,4-trimethylpentanediol, hydroquinone, bis(2-hydroxyethyl)hydroquinone, 4 a group consisting of 4'-dihydroxybiphenyl, bisphenol A, bisphenol F, and mixtures thereof. The method of claim 3, wherein in the step a2), the hardening process is carried out at 70 to 100 ° C for 4 to 48 hours. The method of claim 1, wherein in the step a), the object subjected to supercritical fluid extraction is contained in the polymer resin sheet in an amount of 5 to 50% by weight. The method of claim 1, wherein the supercritical fluid comprises: supercritical carbon dioxide, supercritical isobutane, supercritical butane, supercritical propane, supercritical pentane, and One or more of supercritical nitrogen. The method of claim 1, wherein the step b) is carried out at a pressure of 50 to 300 atm and a temperature of 25 to 120 °C. The method of claim 1, wherein in the step b), the pores formed in the polymer resin sheet have an average diameter of 80 μm or less. The method of claim 1, wherein in the step b), the plate having the pores formed in the polymer resin sheet has a density of 0.5 to 1 g/cm ³ . The method of claim 1, wherein in step b), the polymer resin sheet having the pores has a porosity of 50% or less. A porous plate manufactured by the method of any one of claims 1 to 11. A polishing pad comprising the porous plate of claim 12 of the patent application.