TWI450811B - A storage tank and a polishing pad manufacturing method using the same - Google Patents

Description

Storage tank and polishing pad manufacturing method using the same Field of invention

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a storage tank for containing a resin composition, and more particularly to a storage tank which can be used for manufacturing a polishing pad from a resin composition having high viscosity or high thixotropic thixotropy property. Further, the present invention relates to a method of manufacturing a polishing pad which can perform flattening processing of a material requiring high surface flatness, such as a lens, a mirror, or the like, or a silicon wafer or a hard disk, with high stability and high polishing efficiency. A glass substrate, an aluminum substrate, and a general metal polishing process. The polishing pad of the present invention is particularly applicable to a step of planarizing an element such as an oxide layer and a metal layer formed thereon and before forming an oxide layer and a metal layer again. The steps.

Background of the invention

Representative examples of materials requiring high surface flatness include a disk of a single crystal germanium called a germanium wafer for manufacturing a semiconductor integrated circuit (IC, LSI). In the process of IC, LSI, etc., in order to form a reliable semiconductor junction with various thin films used to form a circuit, in the steps of laminating or forming an oxide layer or a metal layer, it is required that the surface be trimmed with high precision. flat. In this step of polishing, in general, the polishing pad is fixed to a rotatable supporting disk called a platen, and the workpiece of the semiconductor wafer or the like is fixed to the polishing pad. Then, by the movement of both sides, a relative speed is generated between the platform and the polishing pad, and then the abrasive slurry containing the abrasive grains is continuously supplied onto the polishing pad, thereby performing the grinding operation.

The polishing pad is preferably formed of a polyurethane foam. As a method for producing the polyurethane foam, for example, the following method has been proposed.

A method for producing a polyurethane foam has been proposed, in which a mold is placed at the bottom of a storage tank, and a polyurethane foam forming composition is injected into the mold from a valve provided at the bottom portion, and then injected. The polyurethane foam forming composition is reacted and cured to produce a polyurethane foam (Patent Document 1).

However, in the method of Patent Document 1, when the composition for forming a polyurethane foam has high viscosity or high thixotropic viscosity reducing property, liquid clogging occurs due to difficulty in discharging the composition from the valve; Alternatively, the raw material or the cured product adhering to the inside of the valve may be mixed into the composition to lower the quality of the product, or the air gap may easily occur when the composition is injected into the mold from the valve.

Moreover, a method of producing a resin molded body is provided, which comprises: a first step of introducing a raw material for forming a resin molded body into a storage tank; and flowing a raw material for forming a resin molded body into the storage tank into a molding die; The second step of curing is characterized in that the first step is performed in a state where the opening portion formed on the side surface of the sump is closed by the sill member, and the sill member is opened in the second step to open the opening The portion is opened, and the raw material for forming a resin molded body flows into the molding die that is disposed below the opening (Patent Document 2).

However, in the method of the patent document 2, when the raw material for forming a resin molded body has a high viscosity or a high thixotropic viscosity reducing property, there is a problem in that an air gap or the like easily occurs when the raw material for forming a resin molded body flows into the molding die. Further, since the raw material adhering to the inner wall of the sill member is likely to fall on the liquid surface, there is a problem that the resin molded body is liable to cause poor quality.

Advanced technical literature Patent literature

Patent Document 1: Japanese Patent No. 3455187

Patent Document 2: Japanese Patent Laid-Open Publication No. 2008-137355

It is an object of the present invention to provide a sump for producing an air-void and good quality polishing pad, a method of manufacturing the polishing pad using the sump, and a polishing pad obtained by the manufacturing method. Further, it is also an object of the invention to provide a method for producing a semiconductor device using the polishing pad.

The inventors of the present invention have repeatedly reviewed the above problems in order to solve the above problems, and as a result, have found that the above objects can be attained by the above-described storage tank and the manufacturing method, and the present invention has been completed.

In other words, the present invention relates to a storage tank for accommodating a resin composition, wherein the storage tank is formed by connecting two or more body members in a frame shape by a joint portion, and the joint portion is at least one joint portion. A switch member that connects adjacent body members to each other to be opened on both sides is provided, and at least one other connection portion is provided with a joint member that connects adjacent body members to each other in an open shape.

The general storage tank is composed of one body having no connection portion, but the storage tank of the present invention is configured by connecting two or more body members to a frame shape by a joint portion. Further, at least one of the connecting portions is provided with a switch member that connects the adjacent body members to each other to be opened to both sides, and the other at least one of the joint portions is provided with a link that connects the adjacent body members to each other in an open shape. member. According to this configuration, since the switch member can be opened and the adjacent body members are moved to each other to open to both sides, if the storage tank is provided in the mold, the resin composition accommodated in the sump can be poured from the side of the sump into the mold. .

In a preferred embodiment of the present invention, a storage tank formed by connecting three or more trunk members to a cylindrical shape by a connecting portion is provided, and the joint portions at one location are provided so that adjacent body members are mutually connected. The switch member that is opened to both sides is connected, and the other two joint portions are provided with a joint member that connects the adjacent body members to each other in an open shape. By forming the storage tank into a cylindrical shape, the resin material can be uniformly stirred and mixed in the storage tank, whereby a uniformly mixed resin composition can be prepared. In addition, in order to make the storage tank into a simple structure, the number of the body member and the connecting portion is preferably small. However, when the two body members are connected to each other in a cylindrical shape to form a storage tank, the switch member is opened. When the adjacent body members are moved to each other to open to both sides, it becomes difficult to fix the tank in the mold, which becomes complicated in the process. On the other hand, when the three trunk members are connected in a cylindrical shape to form a sump by the connecting portion, when the switch member is opened and the adjacent body members are moved to each other to open to both sides, the remaining one can be The body member is fixed in the mold and is ideal in the process.

Further, the present invention relates to a method of producing a polishing pad comprising the steps of producing an abrasive layer formed of a polyurethane resin, and the foregoing steps, comprising: step (A), which comprises a polyurethane resin composition Storing in the aforementioned storage tank provided in the mold; and step (B), opening the switch member which has been disposed in the storage tank, and moving the adjacent body members to open to each other, thereby making the polyamine in the storage tank The formate resin composition is cast into the mold; and the step (C) is to cure the cast polyurethane resin composition, thereby producing a polyurethane resin.

According to the above manufacturing method, even if the polyurethane resin composition has high viscosity or high thixotropic viscosity reducing property, the polyurethane resin composition in the storage tank can be poured into the mold by a simple operation. There is no air gap inside. Further, there is an advantage that the raw material adhering to the inner wall of the storage tank is not easily mixed into the polyurethane resin composition in the mold. As a result, a high quality polishing pad can be produced.

The step (A) may be a step of stirring a first component containing an isocyanato group-containing compound and a quinone-based surfactant in a storage tank in the presence of a non-reactive gas. The reactive gas is dispersed as fine bubbles to prepare a bubble dispersion, and the second component containing the active hydrogen-containing compound is mixed with the prepared bubble dispersion to prepare and store the polyurethane resin composition. According to this method, it is possible to produce a polishing pad composed of a polyurethane foam having fine bubbles without using hollow beads or the like.

Furthermore, the present invention relates to a method of fabricating a semiconductor device comprising the step of polishing a surface of a semiconductor wafer using the aforementioned polishing pad.

Simple illustration

Figure 1a is a plan view schematically showing the structure of the sump.

Figure 1b is a front elevational view schematically showing the structure of the sump.

Fig. 2a is a schematic view showing the structure of the connection portion of the storage tank at the time of opening.

Fig. 2b is a schematic view showing the structure of the joint portion of the sump at the time of occlusion.

Figure 3a is a schematic view showing the structure of the joint of the sump when it is open.

Figure 3b is a schematic view showing the structure of the joint of the sump at the time of occlusion.

Fig. 4a is a schematic cross-sectional view showing a state before the bottomless storage tank is placed in the mold.

Fig. 4b is a schematic cross-sectional view showing a state in which the bottomless storage tank is placed in the mold.

Fig. 5a is a schematic cross-sectional view showing a state before the bottomless storage tank is placed in the mold.

Fig. 5b is a schematic cross-sectional view showing a state in which the bottomless storage tank is placed in the mold.

Fig. 6a is a schematic plan view showing a state in which a storage tank containing a polyurethane resin composition is placed in a mold.

Fig. 6b is a schematic cross-sectional view taken along line A-A' of Fig. 6a.

Fig. 7a is a schematic plan view showing a state in which adjacent carcass members are moved to each other to be opened to both sides to cast the polyurethane resin composition in the sump into the mold.

Fig. 7b is a schematic cross-sectional view of A-A' of Fig. 7a.

Fig. 8a is a schematic plan view showing a state in which the polyurethane resin composition in the storage tank is poured into a mold.

Fig. 8b is a schematic cross-sectional view of A-A' of Fig. 8a.

Detailed description of the preferred embodiment

Embodiments of the present invention will be described with reference to the drawings. Figure 1a is a top plan view schematically showing the architecture of the sump of the present invention. Figure 1b is a front elevational view schematically showing the architecture of the sump of the present invention. In the storage tank 1 , two or more carcass members 2 are connected in a frame shape by the connecting portion 3 , and at least one of the connecting portions 3 is provided with a switch that connects adjacent carcass members 2 to each other to be opened to both sides. The member 4 is provided with a coupling member 5 that connects the adjacent trunk members 2 to each other in a door shape at at least one other connecting portion 3. Fig. 1a shows a storage tank 1 in which three body members 2 are connected in a cylindrical shape by a joint portion 3. The storage tank 1 is preferably cylindrical, but may be in the shape of a triangular cylinder, a quadrangular cylinder or a polygonal cylinder. Further, when the storage tank 1 has a cylindrical shape, it is preferable to be constituted by three carcass members 2, and it is preferable to form the three carcass members 2 having the same arc length. Although the storage tank 1 should have no bottom, it can also have a bottom. The switch member 4 is provided to maintain the closed state. The body member 2 provided with the switch member 4 may also be provided with a handle member 6 for making the body member 2 easy to switch.

Fig. 2a and Fig. 3a are schematic views showing the structure of the joint portion of the sump of the present invention at the time of opening. Fig. 2b and Fig. 3b are schematic views showing the structure of the joint portion of the sump of the present invention at the time of occlusion. The connecting portion 3 is provided with a connecting member 5 such as a hinge that connects the adjacent body members 2 to each other in an open shape. Further, in order to prevent liquid leakage, the connecting portion 3 is preferably provided with a sealing member 7 such as a foam or a non-foaming body, and preferably has a structure in which a surface seal or a line (dot) seal is applied by elastic deformation of the sealing member 7. .

The inner diameter of the storage tank 1 is preferably several times the outer diameter of the blade of the mixer, and the height of the storage tank 1 is preferably such that the resin composition stirred by the mixer does not overflow. The capacity of the storage tank 1 is not particularly limited, and is generally about 2 to 90 liters.

The sump of the present invention may also be provided with a mixer for modulating the resin composition.

Next, a method of manufacturing a polishing pad composed of a cured resin using the above-described storage tank will be described.

First, a storage tank is provided in the mold. When the storage tank has a bottom, it may be placed in the mold after the resin composition is stored in the storage tank. Fig. 4a and Fig. 5a are schematic cross-sectional views showing the state before the bottomless storage tank is placed in the mold. 4b and 5b are schematic cross-sectional views showing a state in which the bottomless storage tank is placed in the mold.

The outer peripheral surface of the bottom of the sump is preferably provided with an auxiliary member 8 for allowing the sump to be easily placed on the surface of the mold 12. In order to prevent leakage of liquid from the bottom, the auxiliary member 8 is preferably provided with a sealing member 9 such as a foam or a non-foam. In the case where the auxiliary member 8 is not provided, the sealing member 9 may be directly provided at the bottom of the sump. On the other hand, as shown in Fig. 5a, a sealing member 9 may be provided on the surface of the mold 12. As shown in Figs. 4b and 5b, by providing the sump in the mold, the sealing member 9 is elastically deformed to form a planar seal or a line (dot) seal.

Moreover, in order to reduce the frictional resistance between the bottom surface of the body member and the mold surface at the time of switching, the auxiliary member 8 of the two body members 2 which are opened to both sides is preferably provided with the frictional resistance reducing member 10 such as a fluorine-based resin plate.

Next, the resin composition is housed in a storage tank which is provided in the mold. Each of the raw materials may be placed in a storage tank, stirred and mixed to prepare a resin composition in the storage tank, or the resin composition prepared in advance may be put into a storage tank.

The resin for constituting the polishing pad (abrasive layer) is not particularly limited, and examples thereof include a polyurethane resin, a polyester resin, a polyamide resin, an acrylic resin, a polycarbonate resin, and a halogen resin (poly Polychlorinated vinyl, polytetrafluoroethylene, polyfluorovinylidene, polystyrene, olefin resin (polyethylene, polypropylene, etc.), epoxy resin, photosensitivity a mixture of resins and the like. It is particularly desirable as a material for forming a polishing pad because the polyurethane resin has excellent abrasion resistance and can easily obtain a polymer having desired physical properties by various changes in the composition of the raw material. material.

Hereinafter, a case where the resin constituting the polishing pad (polishing layer) is a polyurethane resin will be described.

The polyurethane resin is composed of an isocyanate component, a polyol component (such as a high molecular weight polyol, a low molecular weight polyol), and a chain extender.

As the isocyanate component, a conventionally known compound in the technical field of polyurethanes can be used without particular limitation. The isocyanate component may, for example, be 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'- Diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, p-phenylene diisocyanate, meta-phenyl diisocyanate, p-xylylene diisocyanate, An aromatic diisocyanate such as benzodimethyl diisocyanate; ethylene diisocyanate; 2,2',4-trimethyl hexamethylene diisocyanate; Aliphatic isocyanate such as 1,6-hexamethylene diisocyanate; 1,4-cyclohexane isocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate An alicyclic isocyanate such as norbornane diisocyanate. It is possible to use one type or a mixture of two or more types.

The isocyanate component may be a trifunctional or higher polyfunctional polyisocyanate compound in addition to the above isocyanate compound. As the polyfunctional isocyanate compound, a series of isocyanate adduct compounds such as Desmodur-N (manufactured by Bayer Co., Ltd.) or Duraneeto (manufactured by Asahi Kasei Kogyo Co., Ltd.) are commercially available.

The high molecular weight polyol may, for example, be a polyether polyol typified by polytetramethylene ether glycol, a polyester polyol typified by polybutylene adipate, or polycaprolactone. a polyhydric alcohol, a polyester polycarbonate polyol exemplified by a reaction product of a polyester diol such as polycaprolactone and an alkylene carbonate, and a reaction of a pendant ethyl carbonate with a polyvalent alcohol, followed by A polyester polycarbonate polyol obtained by reacting the obtained reaction mixture with an organic dicarboxylic acid, and a polycarbonate polyol obtained by transesterification of a polyhydroxy compound with an aryl carbonate, and the like. These may be used alone or in combination of two or more.

It can be used together with high molecular weight polyalcohol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol , 2,3-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentane Alcohol, diethylene glycol, triethylene glycol, 1,4-bis(2-hydroxyethoxy)benzene, trimethylolpropane, glycerin, 1,2,6-hexanetriol, neopentyl alcohol, Tetramethylol cyclohexane, methyl glucoside, sorbitol, mannitol, dulcitol, sucrose, 2,2,6,6-anthracene (hydroxymethylcyclohexanol, Low molecular weight polyols such as diethanolamine, N-methyldiethanolamine, and triethanolamine. Further, low molecular weights such as ethylenediamine, toluenediamine, diphenylmethanediamine, and diethylidenetriamine may be used in combination. Polyamine. Alternatively, an alcohol amine such as monoethanolamine, 2-(2-aminoethylamino)ethanol or monopropanolamine may be used in combination. These low molecular weight polyols, low molecular weight polyamines, etc. may be used alone. Two or more kinds may be used in combination.

When the polyurethane resin is produced by the prepolymer method, a chain extender is used for the hardening of the prepolymer. The chain extender is an organic compound having at least two active hydrogen atoms, and the active hydrogen group may, for example, be a hydroxyl group, a first or second amine group, a thiol group (SH) or the like. Specific examples thereof include polyamines exemplified by 4,4'-methylenebis(o-chloroaniline) (MOCA), 2,6-dichloro-p-phenylenediamine, 4,4 '-Methylene di(2,3-dichloroaniline), 3,5-bis(methylthio)-2,4-toluenediamine, 3,5-bis(methylthio)-2,6- Toluene diamine, 3,5-diethyltoluene-2,4-diamine, 3,5-diethyltoluene-2,6-diamine, 1,3-propanediol-di-p-aminobenzoic acid Ester, polyoxytetramethylene-p-aminobenzoic acid ester, 4,4'-diamino-3,3',5,5'-tetraethyldiphenylmethane, 4,4'-diamine Base-3,3',5,5'-tetraisopropyldiphenylmethane, 1,2-bis(2-aminophenylthio)ethane,-4,4'-diamino-3 , 3'-diethyl-5,5'-dimethyldiphenylmethane, N,N'-di-t-butyl-4,4'-diaminodiphenylmethane, 3,3'- Diethyl-4,4'-diaminodiphenylmethane, meta-xylylenediamine, N,N'-di-t-butyl-p-phenylenediamine, meta-phenylenediamine P-xylylenediamine; or the above low molecular weight polyol or low molecular weight polyamine. It is possible to use one type or two or more types.

The ratio of the isocyanate component, the polyol component, and the chain extender can be variously changed depending on the individual molecular weight, the desired physical properties of the polishing pad, and the like.

Although the prepolymer method and the one-shot method can be used for the production of the polyurethane resin, the terminal isocyanate prepolymer is synthesized from the isocyanate component and the polyol component in advance. The polyurethane resin obtained by the prepolymer method of the chain extender reaction is excellent in physical properties and is very suitable.

The polyurethane resin is produced by mixing and curing a first component containing an isocyanate group-containing compound and a second component containing an active hydrogen group-containing compound. In the prepolymer process, the terminal isocyanate prepolymer becomes a compound containing an isocyanate group, and the chain extender becomes a compound containing an active hydrogen group. In the single shot method, the isocyanate component becomes a compound containing an isocyanate group, and the chain extender and the polyol component become a compound containing an active hydrogen.

Although the polyurethane resin may be a foam or a non-foam, it is preferably a foam in consideration of the polishing property of the polishing pad.

Examples of the method for producing the polyurethane resin foam include a method of adding hollow beads, a mechanical foaming method, a chemical foaming method, and the like.

In particular, a mechanical foaming method using an oxime-based surfactant of a copolymer of a polyalkyl siloxane and a polyether is preferred. As such a quinone-based surfactant, SH-192 and L-5340 (manufactured by Toray Dow Corning Silicone Co., Ltd.) and B8465 (manufactured by Goldschmidt Co., Ltd.) can be exemplified as an ideal compound.

In addition, a stabilizer such as a catalyst for promoting a polyurethane reaction such as a third amine or a stabilizer such as an oxidation inhibitor, a slip agent, a pigment, a filler, a charge prevention agent, and the like may be added as needed. additive.

A method of producing a polishing pad composed of a polyurethane resin foam will be described below.

First, the isocyanate group-containing compound and the first component containing the lanthanoid surfactant are stirred in the presence of a non-reactive gas in the storage tank, and the non-reactive gas is dispersed as fine bubbles to prepare a bubble dispersion. Then, the second component containing the active hydrogen group-containing compound is added to the prepared bubble dispersion, and the mixture is stirred and mixed to prepare a foamed polyurethane resin composition.

The non-reactive gas used to form the aforementioned fine bubbles is preferably not flammable, and specifically, a rare gas such as nitrogen, oxygen, carbon dioxide, helium or argon or a mixed gas thereof may be exemplified, and the moisture is removed by drying. Air is the most cost-effective.

As a stirring device in which the non-reactive gas is dispersed in the first component in a fine bubble shape, a known stirring device can be used without particular limitation, and specific examples thereof include a homogenizer and a didiser. 2-axis planetary mixer, etc. Although the shape of the stirring blade of the stirring device is not particularly limited, it is preferable to use a whipper type stirring blade to obtain fine bubbles.

Further, it is also preferable to use a different stirring device to prepare the stirring of the bubble dispersion and the mixing after the addition of the second component. The stirring which is carried out after the addition of the second component is not a stirring for forming bubbles, and a stirring device which does not entrap large bubbles is preferably used. Such a stirring device is preferably a planetary mixer. The stirring device of the foaming step and the mixing step may also use the same stirring device, and the stirring condition may be adjusted as needed, such as adjusting the rotating speed of the stirring blade.

Thereafter, the switch member provided in the sump is opened, and the adjacent body members are moved to each other to be opened to both sides, whereby the polyurethane resin composition in the sump is poured into the mold.

Fig. 6a is a schematic plan view showing a state in which a storage tank containing a polyurethane resin composition is placed in a mold. Fig. 6b is a schematic cross-sectional view of A-A' of Fig. 6a. The storage tank 1 is configured by connecting three body members to a cylindrical shape by a connecting portion. In the mold 12, in order to fix the position of the storage tank 1 and to cast the polyurethane resin composition 13 into a predetermined shape, it is preferable to provide the frame member 14 in advance.

Fig. 7a is a schematic plan view showing a state in which adjacent carcass members are moved to each other to be opened to both sides to cast the polyurethane resin composition in the sump into the mold. Fig. 7b is a schematic cross-sectional view of A-A' of Fig. 7a. Each of the body members 2 that have been actuated is preferably fixed in position by the frame member 14.

Fig. 8a is a schematic plan view showing a state in which the polyurethane resin composition in the storage tank is poured into a mold. Fig. 8b is a schematic cross-sectional view of A-A' of Fig. 8a.

According to the above method, even in the case where the polyurethane resin composition has high viscosity or high thixotropic viscosity reducing property, the polyurethane resin composition in the storage tank can be prevented from occurring by a simple operation. The air gap is poured into the mold. Further, since the raw material adhering to the inner wall of the storage tank is not easily poured in the vicinity of the inner wall, there is an advantage that it is difficult to mix the entire polyurethane resin composition in the mold.

Thereafter, the cast polyurethane resin composition is cured to prepare a polyurethane foam. The storage tank is preferably removed before the polyurethane composition is hardened.

In the method for producing a polyurethane foam, it is preferable to heat and post-cure the foam which has reacted so as not to flow, and to improve the physical properties of the foam.

Thereafter, the polyurethane foam block in the mold was taken out, and the polishing layer (single layer type polishing pad) was produced by cutting to a predetermined thickness using a band saw or a can on a can. The thickness of the polyurethane foam block is not particularly limited, but is generally about 50 to 100 mm. Although the thickness of the polishing pad is not particularly limited, it is generally about 0.8 to 4 mm, and preferably 1.0 to 2.5 mm.

The thickness deviation of the abrasive layer is preferably less than 100 μm. A thickness deviation of more than 100 μm causes a large distortion of the polishing layer, which causes a difference in the contact state of the abrasive material, and adversely affects the polishing property. Further, in order to eliminate variations in the thickness of the polishing layer, in general, the surface of the polishing layer is trimmed using a dresser that has been electrodeposited or fused with diamond abrasive grains at the initial stage of polishing, but if the thickness deviation exceeds the above range, the dressing time is due to the trimming time. Stretched, production efficiency is reduced.

As a method of suppressing variations in the thickness of the polishing layer, a method of polishing the surface of the polishing layer cut to a predetermined thickness can be mentioned. Further, in the case of polishing, it is preferable to carry out stepwise execution with different abrasive materials such as particle size.

The average bubble diameter of the polishing layer is preferably 20 to 80 μm, more preferably 30 to 60 μm.

The ASKER-D hardness of the polishing layer is preferably 45 to 65 degrees, more preferably 55 to 65 degrees.

The specific gravity of the polishing layer is preferably 0.6 to 0.87, more preferably 0.75 to 0.85.

The abrasive surface of the abrasive layer that is in contact with the material to be polished preferably has a textured structure for holding and renewing the slurry. The polishing layer composed of the foam has a function of holding and renewing the slurry while having a large number of openings in the polishing surface, but the slurry can be more effectively and efficiently retained by the formation of the uneven structure on the polishing surface. Prevent damage to the material to be polished caused by adsorption of the material to be ground. The uneven structure is not particularly limited as long as it can maintain and renew the shape of the slurry, and examples thereof include an XY lattice groove, a concentric circular groove, a through hole, a non-through hole, a polygonal column, a cylinder, a spiral groove, and an eccentricity. A combination of a circular groove, a radial groove, and such grooves. Further, although the uneven structure is generally regular, the groove distance, the groove width, and the groove depth may be changed every certain range in order to maintain the slurry and maintainability. .

The polishing pad of the present invention may also be formed by bonding the polishing pad to the gasket.

The aforementioned gasket (cushion) is used to compensate for the characteristics of the polishing layer. In the CMP process, a spacer is necessary in order to balance both the planarity and the uniformity of the trade-off relationship. The flatness refers to the flatness of the pattern portion when the material to be polished (having minute irregularities occurring when forming a pattern) is polished; the uniformity refers to the uniformity of the material to be polished. The flatness can be improved by the characteristics of the polishing layer, and the uniformity can be improved by the characteristics of the gasket. In the polishing pad of the present invention, the spacer should preferably be softer than the abrasive layer.

Examples of the gasket include a fiber nonwoven fabric such as a polyester nonwoven fabric, a nylon nonwoven fabric, an acrylic nonwoven fabric, a polyester nonwoven fabric impregnated with a polyurethane, and a polyurethane nonwoven fabric, and a polyurethane foam. A polymer resin foam such as a polyethylene foam, a rubber resin such as butadiene rubber or isoprene rubber, or a photosensitive resin.

As a means for bonding the polishing layer and the spacer, for example, a method in which the polishing layer and the spacer are pressed by a double-sided tape can be cited.

Further, the polishing pad of the present invention may be provided with a double-sided tape on the joint surface with the platen.

The semiconductor element is manufactured by the step of polishing the surface of the semiconductor wafer using the aforementioned polishing pad. The semiconductor wafer generally means a wiring metal and an oxide film laminated on a germanium wafer. The polishing method and the polishing apparatus for the semiconductor wafer are not particularly limited. For example, a polishing apparatus having the following mechanism may be used: a polishing pad supporting the polishing pad (abrasive layer); and a support table supporting the semiconductor wafer (polishing) Head); a gasket material for uniformly pressurizing the wafer; and a supply mechanism for the abrasive. The polishing pad can be attached to the polishing pad, for example, by adhesion of a double-sided tape. The polishing flat plate and the support table are disposed such that the polishing pads supported by the two are opposed to the semiconductor wafer, and each has a rotating shaft. Further, a pressurizing mechanism for pressing the semiconductor wafer against the polishing pad is provided on the support table side. At the time of polishing, while polishing the polishing pad and the support table, the semiconductor wafer is pressed against the polishing pad, and the slurry is supplied while being polished. The flow rate of the slurry, the polishing load, the number of revolutions of the polishing disk, and the number of wafer revolutions are not particularly limited, and can be appropriately adjusted.

Thereby, the protruding portion of the surface of the semiconductor wafer is removed and ground to a flat shape. Thereafter, the semiconductor element is fabricated by cutting, soldering, packaging, or the like. The semiconductor element can be used for an arithmetic processing device, a memory, or the like.

Example

In the following, the embodiments are described to illustrate the invention, but the invention is not limited by the examples.

[Measurement, evaluation method] (average bubble diameter)

The produced polyurethane foam was cut in parallel into a sheet having a thickness of as small as 1 mm in parallel using a microtom cutter, and was used as a test material for measuring an average cell diameter. The test material was fixed on a glass slide and observed at 100 times using SEM (S-3500N, Hitachi SCIENCE SYSTEMS Co., Ltd.). Using the image analysis software (WinRoof, Mitani Co., Ltd.), the obtained image was measured for the total bubble diameter in an arbitrary range, and the average bubble diameter was calculated.

(proportion)

Executed according to JIS Z8807-1976. The prepared polyurethane foam was cut into a short mark of 4 cm × 8.5 cm (thickness: arbitrary), and it was made into a test material for specific gravity measurement at a temperature of 23 ° C ± 2 ° C and a humidity of 50% ± Allow to stand for 16 hours in a 5% environment. The measurement was carried out using a hydrometer (manufactured by Sartorius Co., Ltd.) to measure the specific gravity.

(hardness measurement)

Executed in accordance with JIS K6253-1997. The prepared polyurethane foam was cut into a size of 2 cm × 2 cm (thickness: arbitrary), and it was used as a test material for hardness measurement at a temperature of 23 ° C ± 2 ° C and a humidity of 50% ± 5%. Allow to stand for 16 hours in the environment. The test materials were overlapped during the measurement to a thickness greater than 6 mm. The hardness was measured using a hardness meter (manufactured by Polymer Instruments, Inc., ASKER-D type hardness meter).

Example 1

1229 parts by weight of toluene diisocyanate (2,4-body/2,6-body=80/20 mixture), 272 parts by weight of 4,4'-dicyclohexylmethane diisocyanate, and a number average molecular weight of 1018 were placed in a reaction vessel. 1901 parts by weight of polytetramethylene ether glycol and 198 parts by weight of diethylene glycol were reacted at 70 ° C for 4 hours to obtain an isocyanate terminal prepolymer.

The storage tank shown in Fig. 1 is placed in a mold as shown in Fig. 6. 100 parts by weight of the prepolymer and 3 parts by weight of a lanthanoid surfactant (SH-192, manufactured by Toray Dow Corning Silicone Co., Ltd.) were added to the storage tank and mixed, and the mixture was adjusted to 80 ° C and defoamed under reduced pressure. Thereafter, stirring was carried out for about 4 minutes in a reaction system by using a stirring blade at a number of revolutions of 900 rpm so as to incorporate bubbles. ETHACURE 300 (manufactured by Albemarle, 3,5-bis(methylthio)-2,6-toluenediamine and 3,5-bis(methylthio)-2, which has been previously adjusted to a temperature of 70 ° C, is added thereto, 21 parts by weight of a mixture of 4-toluenediamine was stirred for about 1 minute to prepare a polyurethane resin composition.

Thereafter, as shown in Fig. 7, the adjacent carcass members are moved to each other to be opened to both sides, whereby the polyurethane resin composition in the tank is poured into the mold. The storage tank was removed, and the polyurethane was placed in a furnace at the time when the fluidity of the polyurethane resin composition was lost, and post-curing was performed at 100 ° C for 16 hours to obtain a polyurethane foam block.

The aforementioned polyurethane foam block which had been heated to about 80 ° C was cut with a microtome (manufactured by Amitekku Co., Ltd., VGW-125) to obtain a polyurethane foam sheet (average bubble diameter: 50 μm, Specific gravity: 0.86, hardness: 52 degrees). Next, the surface of the sheet was polished to a thickness of 1.27 mm using a polishing machine (manufactured by Amitekku Co., Ltd.) to prepare a sheet having a thickness precision. The polished sheet was punched in a size of 61 cm in diameter, and a groove having a groove width of 0.25 mm, a groove pitch of 1.50 mm, and a groove depth of 0.40 mm was grooved using a groove processing machine (manufactured by Techno Corporation). The groove is processed to obtain an abrasive layer. A double-sided tape is adhered to the opposite side of the machined surface of the abrasive layer using a stacker. Further, the surface of the corona-treated gasket (manufactured by Toray Co., Ltd., polyethylene foam, Toraypefu, thickness: 0.8 mm) was polished, and bonded to the above-mentioned double-sided tape using a laminator. Moreover, the double-sided tape is bonded to the other side of the gasket by using a stacker to prepare a polishing pad.

Industrial availability

The storage tank of the present invention is used for accommodating a storage tank of a resin composition, and is particularly useful for producing a polishing pad from a resin composition having high viscosity or high thixotropic viscosity reducing property. Moreover, the polishing pad of the present invention can be used for planarization processing of materials requiring high surface flatness, such as optical materials such as lenses and mirrors, or glass substrates for hard disks, aluminum substrates, aluminum substrates, and general metals. Grinding processing, etc. The polishing pad of the present invention is particularly applicable to a process of flattening an element such as an oxide layer and a metal layer formed thereon and forming an oxide layer and a metal layer thereon before forming or forming such an oxide layer and a metal layer. The steps of the process.

1. . . Storage tank

2. . . Carcass member

3. . . Linkage

4. . . Switch member

5. . . Connecting member

6. . . Handle member

7. . . Sealing member

8. . . Auxiliary component

9. . . Sealing member

10. . . Frictional resistance reduction component

11. . . Clamping member

12. . . Molding

13. . . Polyurethane resin composition

14. . . Frame member

Figure 1a is a plan view schematically showing the structure of the sump.

Figure 1b is a front elevational view schematically showing the structure of the sump.

Fig. 2a is a schematic view showing the structure of the connection portion of the storage tank at the time of opening.

Fig. 2b is a schematic view showing the structure of the joint portion of the sump at the time of occlusion.

Figure 3a is a schematic view showing the structure of the joint of the sump when it is open.

Figure 3b is a schematic view showing the structure of the joint of the sump at the time of occlusion.

Fig. 4a is a schematic cross-sectional view showing a state before the bottomless storage tank is placed in the mold.

Fig. 4b is a schematic cross-sectional view showing a state in which the bottomless storage tank is placed in the mold.

Fig. 5a is a schematic cross-sectional view showing a state before the bottomless storage tank is placed in the mold.

Fig. 5b is a schematic cross-sectional view showing a state in which the bottomless storage tank is placed in the mold.

Fig. 6a is a schematic plan view showing a state in which a storage tank containing a polyurethane resin composition is placed in a mold.

Fig. 6b is a schematic cross-sectional view taken along line A-A' of Fig. 6a.

Fig. 7a is a schematic plan view showing a state in which adjacent carcass members are moved to each other to be opened to both sides to cast the polyurethane resin composition in the sump into the mold.

Fig. 7b is a schematic cross-sectional view of A-A' of Fig. 7a.

Fig. 8a is a schematic plan view showing a state in which the polyurethane resin composition in the storage tank is poured into a mold.

Fig. 8b is a schematic cross-sectional view of A-A' of Fig. 8a.

1. . . Storage tank

2. . . Carcass member

3. . . Linkage

4. . . Switch member

5. . . Connecting member

6. . . Handle member

Claims (4)

A storage tank for accommodating a resin composition, wherein the storage tank is formed by connecting two or more body members in a frame shape by a joint portion, and is provided at at least one joint portion The adjacent body members are coupled to each other to form a switch member that can be opened to both sides, and the other at least one joint portion is provided with a joint member that can connect the adjacent body members to each other to form a door shape. The storage tank of claim 1, wherein the storage tank is cylindrical, and the number of the body members is three. A method for producing a polishing pad, comprising the steps of: forming a polishing layer formed of a polyurethane resin, and the foregoing step comprises: step (A): accommodating the polyurethane resin composition in a mold that has been placed in the mold For example, in the storage tank of claim 1 or 2; step (B): opening the switch member provided in the aforementioned storage tank, and moving the adjacent body members to open to each other, thereby making the polyamine in the storage tank The formate resin composition is cast in a mold; and the step (C): the cast polyurethane resin composition is cured to prepare a polyurethane resin. The method for producing a polishing pad according to claim 3, wherein the step (A) is a step of: containing an isocyanate group-containing compound and a quinone-based surfactant in a storage tank and in the presence of a non-reactive gas. The first component is stirred, the non-reactive gas is dispersed as fine bubbles to prepare a bubble dispersion, and the second component containing the active hydrogen-containing compound is mixed with the prepared bubble dispersion to prepare a polyurethane resin. The composition is contained and contained.