JP2003011066A - Polishing tool and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing tool capable of obtaining the stability in polishing speed and satisfactory difference in step characteristic and reducing a defect (scratch) occuring on a polishing face of an object to be polished of a semiconductor wafer for various objects to be polished. SOLUTION: This polishing tool polishing the object to be polished through abrasive grains 5 by sliding while pressing the object to be polished is mainly composed of thermoplastic resin 4. Butadiene stylene and a polybutadiene or acrylic rubber MBS resin are preferable as the thermoplastic resin. Here, the polishing tool is a fixed abrasive grain polishing tool containing abrasive grains in the polishing tool or a polishing pad containing non-fixed abrasive grains.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing tool and a method for manufacturing the same, and more particularly to a fixed-abrasive polishing tool or a polishing pad used in a polishing apparatus for polishing a polishing object such as a semiconductor wafer into a flat and mirror-like shape. Of the polishing tool of.

[0002]

2. Description of the Related Art In recent years, as the degree of integration of semiconductor devices has increased, the wiring of circuits has become finer and the dimensions of integrated devices have also become finer. Therefore, it may be necessary to remove the coating film formed on the surface of the semiconductor wafer by polishing to flatten the surface. As a method of this flattening method, a chemical mechanical polishing (CMP) apparatus is used. It is being polished. This type of chemical / mechanical polishing (CMP) device has a turntable having a polishing cloth (pad) attached thereto and a top ring, and an object to be polished is interposed between the turntable and the top ring to form a top ring. Rotate while applying a constant pressure to the turntable, and supply the abrasive liquid (slurry) to the polishing cloth to polish the surface of the object to be polished flat and mirror-like.

Chemistry using such a polishing liquid (slurry)
In mechanical polishing (CMP), since polishing is performed while supplying a polishing liquid (slurry) containing a large amount of polishing grains to a relatively soft polishing cloth, there is a problem in pattern dependence. The pattern dependency means that the uneven pattern existing on the semiconductor wafer before polishing forms gentle unevenness due to the unevenness even after polishing, and it is difficult to obtain perfect flatness. That is, the polishing rate is high for the fine pitch irregularities, and the polishing rate is low for the large pitch irregularities, whereby gentle irregularities are formed between the high polishing rate portion and the low polishing rate portion. Is a problem. Further, in polishing with a polishing pad (pad), not only the convex and concave portions of the unevenness but also the concave portion are polished. Therefore, there is a so-called self-stop function in which polishing is stopped when only the convex portion is completely flattened. It was difficult to realize.

On the other hand, polishing of semiconductor wafers using a so-called fixed-abrasive polishing tool in which abrasive grains such as cerium oxide (CeO ₂ ) is fixed using a binder such as phenol resin has been studied. In polishing with such a fixed-abrasive polishing tool, since the abrasive material is hard unlike conventional chemical mechanical polishing, convex and concave portions are preferentially polished, and concave portions are difficult to be polished, so absolute flatness is achieved. Has the advantage of being easy to obtain. Further, depending on the composition of the fixed-abrasive polishing tool, when the polishing of the convex portion is completed and the surface becomes flat, the polishing rate is remarkably reduced, and a so-called self-stop function in which polishing practically does not proceed appears. Further, since polishing using a fixed-abrasive polishing tool does not use a suspending liquid (slurry) containing a large amount of abrasive grains, there is an advantage that the load of environmental problems is reduced.

However, the polishing using the fixed-abrasive polishing tool has the following problems. That is, in manufacturing a semiconductor device, the polished surface of the semiconductor wafer after chemical / mechanical polishing (CMP) needs to have high flatness and prevent scratches (scratches) from occurring. General chemistry
It is known that in polishing with a polishing pad for mechanical polishing (CMP), scratches are likely to occur on the polishing surface when the hardness of the pad is high. Therefore, a soft foaming agent is used for the pad material. On the other hand, since the semiconductor fixed abrasive polishing tool uses a material harder than the pad, a high flatness of the polishing surface can be realized, but many scratches are likely to occur on the polishing surface.

Therefore, semiconductor fixed abrasive polishing tools have been used in a relatively narrow range in which the types of binders are very limited and the composition ratio of abrasive grains, binder and pores is well balanced. On the other hand, the objects to be polished are various, such as a silicon substrate, a polysilicon film, an oxide film, a nitride film, and a wiring layer made of aluminum or a copper material. For this reason, it is practically difficult to manufacture a fixed-abrasive polishing tool that has stable polishing speed and good step characteristics according to these various types of polishing objects, and that scratches (scratches) are hard to occur. Met.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and provides stability of a polishing rate, good step characteristics, and is generated on a polished surface of an object to be polished of a semiconductor wafer. It is an object of the present invention to provide a polishing tool and a method for manufacturing the same, which are capable of satisfactorily exhibiting the reduction of defects (scratches) caused by various types of polishing objects.

[0008]

In order to achieve the above object, the invention as set forth in claim 1 is a polishing tool for polishing an object to be polished by pressing and sliding the same. The polishing tool is mainly composed of a thermoplastic resin. Here, since the fixed-abrasive polishing tool of the present invention is formed by molding a mixture of abrasive grains and resin uniformly, the abrasive grains are uniformly dispersed and fixed in the resin matrix.

According to a second aspect of the present invention, there is provided a polishing tool which performs polishing through abrasive grains by sliding while pressing an object to be polished, the polishing tool comprising a plastic resin having hardness, and A polishing tool comprising an elastic element having elasticity existing in a resin.

According to a third aspect of the present invention, the polishing tool is a polishing pad made of non-fixed abrasive grains.

According to a fourth aspect of the invention, the polishing tool is a polishing pad.

Up to now, thermosetting resins such as PVA, phenol resin and epoxy resin have been widely used for fixed abrasive polishing tools such as semiconductor wafers. In the present invention, a thermoplastic resin is used in place of the thermosetting resin, and a resin (polymer material) having an elastic element is used in a plastic material having hardness, so that conventional fixing is performed as described later. It is possible to obtain a fixed-abrasive polishing tool having various characteristics that cannot be obtained with the abrasive-polishing tool. That is, since heat is generated during polishing of a semiconductor wafer or the like, by using a thermoplastic resin for the fixed-abrasive polishing tool or polishing pad, the resin becomes soft due to heat generation during polishing.
This makes it possible to polish with a soft polishing surface and suppress the occurrence of scratches (scratches). Also, by using a hard resin containing an elastic element in the resin, it is possible to obtain a polished surface that is hard when viewed macroscopically and soft when viewed microscopically. This results in excellent flatness and scratches (scratches). Can perform high-quality polishing with a small amount.

According to a fifth aspect of the present invention, the abrasive grains are cerium oxide (CeO ₂ ), alumina (Al ₂ O ₃ ), silicon carbide (SiC), silicon oxide (SiO ₂ ), zirconia (ZrO ₂ ), Iron oxide (FeO, Fe ₃ O ₄ ), manganese oxide (MnO ₂ , Mn ₂ O ₃ ), magnesium oxide (MgO), calcium oxide (CaO), barium oxide (BaO), zinc oxide (ZnO), barium carbonate ( Ba
CO ₃ ), calcium carbonate (CaCO ₃ ), diamond (C), or a composite material thereof.

As a result, it is possible to provide a fixed-abrasive polishing tool which is excellent in polishing rate stability and level difference characteristics and which can be used for polishing with less scratches (scratches) by using a relatively easily available raw material.

According to a sixth aspect of the present invention, the polishing tool is formed by injection molding under pressure into a predetermined mold by an injection molding method. What is injection molding?
This is a method of producing a molded product corresponding to a mold cavity by injecting a heated raw material in a fluid state into a cavity of a closed mold under pressure and solidifying it in the mold. As a result, the fixed-abrasive polishing tool and the like can be easily manufactured with good mass productivity.

The invention according to claim 7 is characterized by containing an acrylonitrile butadiene styrene (ABS) resin. ABS resin is a copolymer of acrylonitrile, butadiene, and styrene. Hard AS (acrylonitrile styrene) on the core of small and soft butadiene rubber
It has a structure in which resin is entangled. As a result, the fixed-abrasive polishing tool made of ABS resin has a polishing action surface that is as hard as the AS resin when viewed macroscopically, achieves high flatness of the object to be polished during polishing, and is soft when viewed microscopically. The butadiene rubber has an impact absorbing effect, which suppresses the occurrence of scratches (scratches) and enables high-quality polishing. In addition, the polishing pad made of ABS resin has a polishing surface that is as hard as the AS resin in macroscopic terms, and has a shock absorbing action by soft butadiene rubber in microscopic terms. The polishing can be realized.

The invention according to claim 8 is characterized in that the resin contains a core-shell type resin having an elastic body containing a rubber material as a core. Here, the resin is butadiene styrene, polybutadiene, or acrylic rubber type MB.
It is preferably S resin. By manufacturing a fixed-abrasive polishing tool using this resin, a high polishing rate can be obtained, and polishing can be performed by a fixed-abrasive polishing tool with extremely few scratches as in the case of ABS resin. or,
In addition to ABS and MBS, a resin having a core-shell structure having an elastic body such as rubber as a core is similarly effective.

According to a tenth aspect of the present invention, the elastic element includes an elastic filler, and the elastic filler includes a rubber filler. As a result, by including small and soft rubber particles as a constituent material of the polishing tool, the same macroscopically hard effect as in the above ABS resin and a microscopically soft effect are obtained, and high-quality polishing is realized. It will be possible. Therefore, even when polishing is performed while supplying slurry containing abrasive grains from the outside, high-quality polishing with few scratches can be realized.

An eleventh aspect of the present invention is characterized in that a surfactant is further added to the material forming the polishing tool. Generally, a polymeric material (resin) used as a binder for fixing abrasive grains in a fixed-abrasive polishing tool has poor wettability with the abrasive grains. Therefore, when formed only with the abrasive grains and the binder, the abrasive grains are dispersed uniformly. However, there is a problem that a large abrasive grain mass is present in the compact. It is said that extremely small abrasive grains fall off during polishing and function as pockets for collecting polishing by-products and polishing debris, and are considered to be useful for polishing. However, large hundreds of n
The m-order abrasive grain agglomerate is immediately separated from the fixed-abrasive polishing tool during polishing, the polishing ability is greatly changed with time, and the polishing ability is immediately deteriorated. further,
This causes a difference in polishing ability within the surface of the polishing tool, which causes uneven polishing, which is a factor of inhibiting polishing. Therefore, it is possible to manufacture a fixed-abrasive polishing tool that enables stable polishing by using a surfactant during the kneading of raw materials, ensuring the wettability of the abrasive grains and the binder, and evenly dispersing the abrasive grains. it can.

A twelfth aspect of the invention is characterized in that a hydrophilic substance is further added to the material constituting the polishing tool. In general, a polymer material exhibits hydrophobicity and repels a polishing liquid, and thus has a problem that the polishing liquid holding capacity is low and it is difficult to perform stable polishing. Therefore, by containing in the pad a hydrophilic substance having a large number of hydrophilic groups on the surface, hydrophilicity can be secured, whereby the polishing liquid can be held evenly on the surface, and stable polishing can be performed.

According to a thirteenth aspect of the present invention, in a fixed-abrasive polishing tool that performs polishing via abrasive grains by sliding while suppressing an object to be polished, the material forming the polishing tool is hydrophilic. It is characterized in that a group is added (modified). As in the eleventh aspect, the polishing liquid can be held evenly on the surface, and stable polishing can be performed.

According to a fourteenth aspect of the present invention, in a fixed-abrasive polishing tool that performs polishing through abrasive grains by pressing and sliding an object to be polished, butadienestyrene is used as the fixed-abrasive polishing tool. The polishing tool is characterized by containing polybutadiene or an acrylic rubber-based MBS resin.

The MBS resin is a copolymer of methyl methacrylate, butadiene, and styrene as raw materials. The rubber layer is a copolymer of butadiene and styrene (SBR) as a core, and the copolymer of methyl methacrylate and styrene is a copolymer. Coalescence (M
It is a core-shell type thermoplastic resin having S) as a shell. In addition to the copolymer of butadiene and styrene (SBR),
There are MBS resins having a core of polybutadiene rubber or polyacrylate rubber. The copolymer (MS) of methyl methacrylate and styrene used for the shell of the MBS resin has a characteristic that the hardness can be reduced by mixing styrene with PMMA, which has a very high hardness as a plastic. PMMA is a resin that has a high hardness but is extremely brittle, and it has been found that this high hardness and brittleness are suitable as a material for a fixed abrasive tool. This resin was particularly effective for scratch properties. Further, it is considered that by mixing styrene with this material and polymerizing, it is possible to lower the hardness and control the brittleness, and it is effective in reducing the material cost. The MBS resin in which the shell of this material is combined with the core of the rubber layer can improve the impact property and can alleviate the impact force from the abrasive grains during the fixed abrasive polishing process. Therefore, it is possible to perform high-quality machining without scratches.

According to a fifteenth aspect of the present invention, in a method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, a mixture of the raw materials is filled in a molding jig, and heating / cooling treatment, and / or It is a method for manufacturing a fixed-abrasive polishing tool, characterized in that it is formed by pressure treatment.

In the sixteenth aspect of the present invention, the abrasive grains and the thermoplastic resin are used as raw materials, and the preamble of filling the raw materials in the molding jig is to mix the abrasive grain powder and the thermoplastic resin during or after the filling. A method of manufacturing a fixed-abrasive polishing tool characterized by the above.

According to a seventeenth aspect of the present invention, in a method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, the abrasive grains or slurry and the raw materials for the thermoplastic resin are used in the step of polymerizing or producing the thermoplastic resin. Is mixed to prepare a dispersion liquid, and a mixed polymer of a thermoplastic resin and abrasive grains is produced in the dispersion liquid. Methods for obtaining (fine) particles of a thermoplastic resin include suspension polymerization and emulsion polymerization. According to these methods, a spherical polymer can be produced in a dispersion liquid of a raw material (monomer) of the thermoplastic resin. By mixing abrasive grains or slurry (abrasive grain dispersion liquid) in the dispersion liquid, it becomes possible to obtain a mixture of the abrasive grains and the resin in the polymerization stage.

According to the eighteenth aspect of the present invention, in a method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, the abrasive grains or slurry and the raw material of the thermoplastic resin are mixed into a dispersion liquid, and the dispersion liquid Among them, the method for producing a fixed-abrasive polishing tool is characterized in that a spray dryer or a spray drying treatment is carried out after a mixed polymer of a thermoplastic resin and abrasive grains is produced therein. Methods for obtaining (fine) particles of a thermoplastic resin include suspension polymerization and emulsion polymerization. According to these methods, a spherical polymer can be produced in a dispersion liquid of a raw material (monomer) of the thermoplastic resin. By mixing abrasive grains or slurry (abrasive grain dispersion liquid) in the dispersion liquid, it becomes possible to obtain a mixture of the abrasive grains and the resin in the polymerization stage. Further, by drying and granulating the obtained mixture fine particles, it becomes possible to obtain a mixture having a size suitable for fixed abrasive production. Further, it becomes possible to improve the uniformity of the ratio between the abrasive grains of the mixed fine particles and the resin.

According to a nineteenth aspect of the present invention, in a method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, 1 to 500 μm is used when polymerizing or producing the thermoplastic resin.
A method for producing a fixed-abrasive polishing tool, characterized in that a mixed polymer of a thermoplastic resin having a particle diameter of m and abrasive grains is obtained. Methods for obtaining (fine) particles of a thermoplastic resin include suspension polymerization and emulsion polymerization. According to these methods, a spherical polymer can be produced in a dispersion liquid of a raw material (monomer) of the thermoplastic resin. By mixing abrasive grains or slurry (abrasive grain dispersion liquid) in the dispersion liquid, it becomes possible to obtain a mixture of the abrasive grains and the resin in the polymerization stage. Further, when the mixture is obtained, the mixture fine particles are adjusted to a size of 1 to 500 μm, which is suitable for the production of fixed abrasive grains, so that the mixed powder can be obtained only by drying.

According to a twentieth aspect of the present invention, in a method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, the abrasive grain powder or slurry and the thermoplastic resin powder before being filled in a molding jig. Alternatively, the emulsion liquid is mixed and dispersed in water or a solvent, and the mixed liquid is subjected to dry powder treatment.

According to a twenty-first aspect of the present invention, in a method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, the abrasive powder powder is dried before being filled in a molding jig, It is characterized in that the dried product and the emulsion liquid of the thermoplastic resin are mixed and dispersed, and the mixed liquid is subjected to dry powder treatment.

According to a twenty-second aspect of the present invention, in a method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, the abrasive powder powder is dried before being filled in a molding jig, and the slurry is dried. It is characterized in that the dried product and the dried product of the thermoplastic resin are dispersed again in water or a solvent, and the mixed solution is subjected to dry powder treatment.

According to a twenty-third aspect of the present invention, in a method for producing fixed abrasive grains as a liquid raw material in which abrasive grains and a thermoplastic resin are mixed, the liquid raw material is dried before being filled in a molding jig. The method for manufacturing a fixed-abrasive polishing tool according to any one of claims 15 to 18 and 20 to 22, characterized in that spray drying treatment is carried out in the step.

According to a twenty-fourth aspect of the present invention, in a method for producing fixed abrasive grains by mixing abrasive grains and a thermoplastic resin as raw materials, the fixed abrasive raw material mixture is dried or dried. After that, the powder is pulverized into powder having a particle size of 1 to 500 μm.
23. The method for manufacturing a fixed-abrasive polishing tool according to any one of 1 to 23. A twenty-fifth aspect of the present invention is a semiconductor wafer polishing apparatus comprising the above-described polishing tool. A twenty-sixth aspect of the present invention is a polishing method characterized by polishing a semiconductor wafer using the above-mentioned polishing tool. The invention according to claim 27 is a method for producing fixed abrasives using abrasives and a resin as raw materials,
Before filling the molding jig, the abrasive particles and the resin are mixed in a liquid, the mixture of the abrasive particles and the resin is subjected to a spray dryer or other spray drying treatment, and the dried mixture is used as a molding jig. A method of manufacturing a fixed-abrasive polishing tool, which comprises filling and molding.

[0034]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 schematically shows a fixed-abrasive polishing tool according to an embodiment of the present invention. Fixed abrasive polishing tool 1 shown in (a)
Is a binder (resin) 4 with abrasive grains 5, pores or pore agent 2
It is configured by combining. Here, a thermoplastic resin such as ABS resin is used as the binder 4. As a result, when the temperature rises, the binder softens and becomes elastic, and acts like a rubber resin, reducing scratches by softly contacting the surface to be polished of the object to be polished during polishing. Then, polishing can be performed.
The fixed-abrasive polishing tool 1 shown in (b) is composed of abrasive grains 5, an elastic filler 3 such as rubber particles, and pores or pore agents 2 bonded by a binder (resin) 4. Here, a hard resin is used as the binder 4. The elastic filler 3 has a function similar to that of rubber particles, and can be softened during polishing and brought into contact with the surface to be polished of the object to be polished, thereby reducing scratches and the like and performing polishing.

In the conventional fixed-abrasive polishing tool, a binder mixed raw material containing abrasive grains is generally formed by compression molding. On the other hand, the fixed-abrasive polishing tool of the present invention is characterized by using a thermoplastic resin, so that the fixed-abrasive polishing tool having a large mass production effect by injection molding, blow molding, vacuum molding, or the like. Can be manufactured. Since the thermoplastic resin has the characteristic that it melts at a certain temperature or higher, it becomes possible to manufacture fixed-abrasive polishing tools with various characteristics that have never existed before. A grain polishing tool can be manufactured. By selecting a fixed-abrasive polishing tool whose main component is a suitable thermoplastic resin for the object to be polished, it is considered that the temperature will be locally high during polishing. Then, it softens and has viscosity. Therefore, the processing pressure applied to the polishing surface by the abrasive grains can be stabilized, and the abrasive grains are not subjected to excessive processing force. That is, the abrasive grains are pressed with a soft tool, and scratches (scratches) on the surface of the object to be polished after polishing can be reduced.

In the present invention, a thermoplastic resin is mainly used as the resin as the binder for fixing the abrasive grains of the fixed abrasive grain polishing tool. Mainly, the binder resin may be 100% thermoplastic resin, but at least 50% or more, preferably 80% or more (more preferably 90% or more) of the binder resin is thermoplastic resin. Indicates that the rest may be composed of thermosetting resin or other materials.
The polishing tool comprises abrasive grains, pores, a binder, and possibly other reinforcing materials, fillers and additives. As will be described later, the thermoplastic resin has a volume ratio of 30 to 8 in the entire polishing tool.
It may be 0 vol%, but in the present invention, it is desired that the thermoplastic resin occupy 40 vol% or more, preferably 50 vol% or more.

Examples of constituent materials of the thermosetting resin and the thermoplastic resin are shown below. Phenol (P
F), urea (UF), melamine (MF), unsaturated polyester (UP), epoxy (EP), silicone (S
I), polyurethane (PUR), etc., and each of these substances is cured by adding a third substance which is a curing agent. Further, the thermoplastic resin includes polyvinyl chloride (PVC) and polyethylene (P
C), polypropylene (PP), polystyrene (P
S), acrylonitrile butadiene styrene (AB
S), butadiene styrene, polybutadiene, or acrylic rubber-based MBS resin (methyl methacrylate butadiene styrene (MBS)), copolymer resin (AS) of styrene monomer and acrylonitrile, polymethylmethacrylic (PMMA), methyl methacrylate and styrene Copolymer (MS) Polyvinyl alcohol (PVA), Polyvinylidene chloride (PVDC), Polyethylene terephthalate (PET), Polyamide (PA) known as engineering plastic, Polyacetal (PO)
M), polycarbonate (PC), polyphenylene ether (PPE (modified PPO)), polybutylene terephthalate (PBT), ultra high molecular weight polyethylene (UHMW)
-PE), polyvinylidene fluoride (PVDF), polysarubone (PSF), which is known as super engineering plastic, and polyethersarubone (PE)
S), polyphenylene sulfide (PPS), polyarylate (PAR), polyamideimide (PAI), polyetherimide (PEI), polyetheretherketone (PEEK), polyimide (PI), liquid crystal polymer (LCP), polytetrafluoro There are ethylene (PTFE) and the like.

The thermosetting resin has a three-dimensional structure or a network structure by heating alone or by adding a second substance, and becomes an infusible and insoluble resin. That is, it is a resin that has the property of not softening once cured. The chemical reaction of this resin becomes active at a certain temperature, curing (crosslinking) starts, and the curing is completed by maintaining the curing temperature for a certain time. In cooling, in order to prevent deformation and generation of internal residual stress, the hardened state is maintained by gradually cooling.
The thermoplastic resin is a resin that has fluidity by being softened without reaction after passing a certain softening temperature by heating.
It solidifies again when cooled. That is, it returns to its original nature.

FIG. 2 schematically shows an injection molding machine. The injection molding machine includes a pressure head 19 for injection molding the liquid material held in the cylinder chamber 16a in the cylinder 16 into the mold 15. The screw 17 is rotated by a hydraulic motor 12 for rotating the screw, so that the screw 1 is turned on.
The resin material charged from 8 is pushed into the space 16 in the cylinder chamber in front of the pressure head 19. A heater 13 is arranged on the peripheral surface of the cylinder 16, and the solid resin material charged is heated by a screw 17 while being moved, and is heated to the melting point of the resin or higher to be converted into a liquid material. Then, the injection head 11 is pressed and moved to the mold 15 side by the injection hydraulic drive machine 11, so that the liquid resin is filled in the void 15 a in the mold 15.

That is, the material in which the abrasive grains and the resin are mainly kneaded is fed through the material feeding port 18 and is fed from the feeding portion 18 to the ejection portion 16a by rotating the screw 17. At that time, the material is heated by the heater 13 and melted into a liquid state. By reciprocating the pressure head 19, the liquid material is injected into the void 15a of the mold 15 and becomes a product shape. After that, the product is cooled and released into a product. Resins for injection molding include vinyl chloride resin, vinylidene chloride resin, polystyrene methacrylic resin, polycarbonate cellulose acetate, polyacetal polyamide, polypropylene, polyethylene, trifluoroethylene resin,
General thermoplastic resins such as vinylidene fluoride resin and some thermosetting resins such as phenol resin, polyester resin and diallyl phthalate can be used, and various resins can be molded. In addition, a large number of molded products can be manufactured at one time, the number of processing steps is smaller than that of compression molding, the manufacturing time can be shortened, not only can complex shapes be manufactured accurately, but also mass production with high efficiency is possible. It will be easier. Further, compression molding and heat treatment combined compression molding are possible by adjusting the mixing ratio of abrasive grains and the resin particle size. Also in this case, since it does not cure at a high temperature, the working time is not limited and the handling is easy.

In particular, when ABS resin is used as the binder, the ABS resin can be softly abraded by the thermoplastic resin when the temperature rises, and at the same time, the ABS resin becomes the core of the butadiene rubber.
Since it has a core-shell structure in which S resin is entangled, even when the temperature generated during polishing is lower than the softening temperature of the resin,
Polishing with less scratches is possible, and high-quality wafer flattening is possible. That is, the ABS resin has an elastic element in its composition itself, is as hard as the AS resin when viewed macroscopically, has a high flatness to be polished during polishing, and when viewed microscopically, The soft butadiene rubber acts as an impact absorber, suppressing scratches (scratches). In addition to the ABS resin, as a resin having a structure in which an elastic body is inserted, there is a resin in which methyl methacrylate butadiene styrene (MBS) is added to vinyl chloride as a modifier. As a result, MBS can act as an elastic element. Similarly, it is hard when viewed macroscopically, and high flatness of the object to be polished can be obtained during polishing. Obtainable.
Further, the fixed abrasive grains containing a large amount of the MBS resin, that is, formed with the binder as the main component, have a large impact absorbing action and are effective.

As shown in FIG. 1B, even if fine rubber particles are kneaded and molded in addition to the abrasive grains and the binder (plastic material), the same effect as that of the ABS resin can be obtained. Specific examples of the rubber particles added to the plastic material include natural rubber (NR) and styrene butadiene (SB).
R), butadiene (BR), chloroprene (CR), butyl (IIR), nitrile (NBR), ethylene propylene (EPM, EPDM), chlorosulfonated polystyrene (CSM), acrylic rubber (acrylic acid alkyl ester and crosslinkable monomer Copolymer ACM, Acrylic alkyl ester and acrylonitrile copolymer A
Acrylic ester such as NM), urethane rubber (U), silicone rubber (SI), fluororubber (FK
M), polysulfide rubber (T), and the like. Particularly, chlorosulfonated polystyrene (CSM) has excellent weather resistance, acid resistance, inorganic chemical resistance, and abrasion resistance, and acrylic rubber (crosslinkable with acrylic acid alkyl ester and crosslinkable). Copolymer ACM with Monomer
Or acrylic acid ester such as copolymer ANM of acrylic acid alkyl ester and acrylonitrile) has excellent heat resistance, fluororubber (FKM) has excellent heat resistance, chemical resistance and weather resistance, and silicone rubber (SI) has Not only is it excellent in heat resistance, but it also has a wide operating temperature range, is not easily altered in the polishing environment, and is very suitable.

In addition to rubber-based particles, elastic hollow particles are similarly effective. For example, hollow particles such as polyacrylonitrile (PAN) may be used.

By the way, in order to perform high-quality polishing,
It is necessary to make the polishing efficiency constant within the working surface of the fixed-abrasive polishing tool, and therefore it is necessary to make the distribution of the abrasive grains uniform.
Many resins are polymeric materials and have poor wettability with abrasive grains that are metal oxides, and the abrasive grains tend to exist as large agglomerates in the fixed-abrasive polishing tool structure. For example, when cerium oxide fine particles are used for the abrasive grains and ABS resin is used for the binder, the wettability with the abrasive grains is poor and the abrasive grains are several meters in the molded product.
Abrasive agglomerates of the order of m to several hundred nm tend to be present. This can be improved by adding a surfactant, and high-quality polishing becomes possible. The method of uniform dispersion is considered to take a sufficient time to knead before molding in addition to the use of a surfactant, but it takes time and is not efficient. If a surfactant is used, the surface tension can be lowered and uniform dispersion can be achieved. For example, a urea resin with a non-ionic activator of 0.
By adding 01-0.2%, the surface tension is about 63.
To about 50 dyne / cm.

Although the above description is about the constitutional example of the fixed-abrasive polishing tool for polishing, the above-mentioned constitutional example uses a polishing liquid (slurry) containing a large amount of polishing abrasive grains to form a semiconductor wafer or the like. The same can be applied to a polishing pad used when polishing. When a resin having a higher hardness is used as the polishing pad, the flatness of the polishing surface can be obtained, but many scratches (scratches) are likely to occur during polishing. Therefore, FIG.
As shown in (a), it is possible to prevent scratches (scratches) by forming the polishing pad with a hard resin 4 and adding small and soft rubber particles 6 in the composition.

Specific examples of the rubber used include natural rubber (NR), styrene butadiene (SBR), butadiene (BR), chloroprene (CR), butyl (IIR), as in the case of the fixed-abrasive polishing tool. Nitrile (NB
R), ethylene propylene (EPM, EPDM), chlorosulfonated polystyrene (CSM), acrylic rubber (copolymer ACM of alkyl acrylate and crosslinkable monomer, copolymer ANM of alkyl acrylate and acrylonitrile) Acrylic ester), urethane rubber (U), silicone rubber (SI), fluororubber (FKM), polysulfide (T), and the like can be used. In particular, chlorosulfonated polystyrene (CSM)
Has excellent weather resistance, acid resistance, inorganic chemical resistance, and abrasion resistance. Acrylic rubber (copolymer ACM of acrylic acid alkyl ester and crosslinked herb monomer, copolymer ACM of acrylic acid alkyl ester and acrylonitrile) Acrylic ester) has excellent heat resistance, and fluororubber (FKM)
Has excellent heat resistance, chemical resistance, and weather resistance.
I) is not only excellent in heat resistance, but also has a wide operating temperature range, is not easily deteriorated in the polishing environment, and is very suitable. In addition to rubber particles, elastic hollow particles are similarly effective. For example, polyacrylonitrile (PA
Hollow particles such as N) can be used. As the resin material, the same material as the material used for the above-mentioned fixed abrasive polishing tool is used.

FIG. 3B shows the case where ABS resin is used for the polishing pad. If the ABS resin 7 is used for the polishing pad, the ABS resin is a resin having a high hardness macroscopically, but its composition contains a small and soft butadiene rubber 8. As a result, the polishing surface is as hard as acrylonitrile styrene (AS: SAN) resin from a macroscopic point of view, and a high flatness of the object to be polished can be obtained at the time of polishing. The shock absorbing action of the grains works, the occurrence of scratches (scratches) is suppressed, and high-quality polishing can be realized.

Next, a typical manufacturing process of ABS resin will be described. The ABS resin is a core-shell type resin in which polybutadiene rubber particles are present in the AS resin. An emulsion polymerization method is a general production method thereof, in which it is relatively easy to control the particle size of the rubber and the interface between the rubber phase and the resin phase. A typical ABS resin manufacturing process is a rubber latex manufacturing process in which butadiene is emulsion-polymerized to form polybutadiene latex, and acrylonitrile and styrene are added to this latex (or abrasive grains are added to these).
It comprises a graft polymerization step in which a graft reaction is carried out by emulsion polymerization, and a post-treatment step in which the graft copolymer is coagulated, dehydrated and dried. Polybutadiene latex is obtained by emulsion polymerization of butadiene, water, an emulsifier, a catalyst and a degree of polymerization modifier, which are basically the same as the emulsion polymerization of synthetic rubber. The obtained polymer is controlled by the polymerization prescription and the polymerization operation conditions in order to control the rubber particle size, gel content (crosslinked structure) and the like. In addition to the emulsion polymerization described above, there is a production process such as a bulk polymerization process in which an AS copolymer latex of only acrylonitrile and styrene is produced in a separate step, mixed with a graft copolymer latex, coagulated, dehydrated and dried, and a graft blend method is used. is there.

Next, a fixed-abrasive polishing tool using butadiene styrene, polybutadiene, or acrylic rubber-based MBS resin will be described. MBS resin in this broad sense is a graft polymer having a core-shell structure having butadiene styrene, polybutadiene, or acrylic rubber as a core, and is mainly used as a modifier for improving impact resistance of vinyl chloride resin or acrylic resin. ing. The MBS resin is a copolymer of methyl methacrylate, butadiene, and styrene as raw materials, and has a rubber layer of a copolymer of butadiene and styrene (SBR) as a core and a copolymer of methyl methacrylate and styrene (MS). ) Is a core-shell type thermoplastic resin.

For a fixed-abrasive polishing tool using a vinyl chloride or acrylic resin added with an MBS resin as a binder, the addition amount is generally several to 20%, and the characteristics of vinyl chloride are important. It was designed. On the other hand, when the ratio of the MBS resin in the resin is 20% or more, 50% or more, or 100%, the tool has a high impact absorbing effect. By using this resin as a binder material and combining it with ceria oxide abrasive grains, a fixed-abrasive abrasive tool with very few scratches during polishing can be obtained. For example, an epoxy resin and an MBS resin may be mixed and used as a binder material. That is, since MBS resin is a thermoplastic resin in this fixed abrasive polishing tool,
Molding is easy, and the strength of the molded product is high. And
When the MBS resin is used as the binder material, there is a self-reaction of the abrasive grains, which gives a high polishing rate. For example, as compared with a fixed-abrasive polishing tool using a conventional epoxy resin as a binder material, a polishing rate about twice as high can be obtained. Further, since the resin itself has impact resistance, the force acting on the abrasive grains during polishing is relaxed (suppressed), and polishing without scratches, that is, with few defects, becomes possible. It is considered that the structural unit of the MBS resin spreads due to the water absorption effect, and the ability to hold the abrasive grains is reduced, so that the abrasive grains can easily grow.

FIG. 4 shows experimental data comparing (a) polishing rate and (b) defect amount with fixed abrasives made of various resin materials. The experiments of FIGS. 4 and 5 were performed by the apparatus shown in FIG. 13 (described later). As shown in FIG.
It can be seen that the fixed abrasive grains using the ABS resin, AS resin, and MBS resin have a considerably higher polishing rate than the fixed abrasive grains using the phenol resin or the epoxy resin. In addition, as shown in FIG. 4B, the amount of defects per unit area of the ABS resin, AS resin, and MBS resin is
Data comparable to or lower than that using a phenol resin or an epoxy resin is obtained. That is, fixed abrasives using a thermoplastic resin generally have a high polishing rate and a small amount of defects. Fixed abrasives using ABS resin and MBS resin have a particularly high polishing rate and tend to have a small amount of defects such as scratches and deposits after polishing.

FIG. 5 shows experimental data comparing (a) polishing speeds and (b) defect amounts of various resin materials with polishing pads containing no abrasive grains. This experimental data is
PC (polycarbonate), Epoxy (epoxy),
It is comparative data about various resins such as Phenol (phenol), ABS (acrylonitrile butadiene styrene), MBS (methyl methacrylate butadiene styrene), PE (high density polyethylene), RB (butadiene rubber) and AS (acrylonitrile styrene). This experimental data also shows that the polishing pad using the ABS resin or MBS resin has a high polishing rate and a small amount of defects.

A structural example of the fixed abrasive grains made of the MBS resin will be described. The grindstone composition ratio (ratio of abrasive grain ratio (Vg), binder ratio (Vb) and porosity (Vp)) (vol%) is, for example, abrasive grain ratio (Vg): binder ratio (Vb): porosity (Vp) = 3
It is 5:55:10 (vol%).

This fixed-abrasive polishing tool is compared with general fixed-abrasive polishing tools using phenol and epoxy resin.
As described above, the processing speed is high and the number of scratches is small, and the present invention can be applied to a semiconductor manufacturing process in which scratches are not preferable. High-speed polishing required without dressing during polishing for processes that require a high polishing rate, such as when a general fixed-abrasive polishing tool made of phenol or epoxy resin needs to be dressed at the same time during polishing. Is obtained.
Further, since there is no concern that diamond abrasive grains will fall off during dressing, scratches due to diamond particles will not occur.

Next, the composition ratio of the fixed-abrasive polishing tool using the MBS resin will be described. Fixed abrasive grain composition ratio (ratio of abrasive grain ratio (Vg) to binder ratio (Vb) to porosity (Vp))
(Vol%) is generally 10% <abrasive grain ratio (Vg) <50% 30% <binder ratio (Vb) <80% 0% <porosity (Vp) <40%, 20% <abrasive grain Ratio (Vg) <45% 40% <Binder ratio (Vb) <70% 0% <Porosity (Vp) <20% is desirable, 30% <Abrasive grain ratio (Vg) <40% 50% <Binder ratio (Vb) <60% 5% <porosity (Vp) <15% is more desirable.

A method of manufacturing this fixed abrasive tool will be described below. First, a dry powder is prepared by mixing fine cerium oxide with butadiene styrene, polybutadiene, or an acrylic rubber-based MBS resin. An example of a specific method for obtaining this mixed dry powder is shown below. The first method is a method in which the abrasive powder and butadiene styrene, polybutadiene, or acrylic rubber-based MBS resin powder are simply mixed, and a mixed dry powder can be easily obtained.

The second method is to naturally dry or heat-dry or freeze an abrasive grain liquid in the form of a slurry in which water and / or an aqueous solution and / or a solvent and / or a binder and / or a chemical are added to the abrasive grains as needed. A butadiene styrene, polybutadiene, or acrylic rubber-based MB is dried by a method such as drying, and then pulverized by pulverization or the like, if necessary.
This is a method of obtaining the mixed dry powder by mixing with S resin powder. However, since the abrasive grains are fine and easily aggregated, in order to powderize the abrasive grains alone, a spray dryer or other spray drying is used, and the cohesive force or the bonding force is weak,
And, an average particle size of 1 to 500 μm suitable for handling and molding,
Desirably 10 to 100 μm, and more desirably 30 to 8
It is desirable to make the powder a size of 0 μm. The binder contained in the abrasive grain slurry is not suitable as a binder that binds firmly, and is not a resin binder with a strong binding force, but a bond with water crosslinking or intermolecular force, or a binder with a weak binding force It is desirable to select (including).

In the third method, after the mixed powder is obtained by the first and second methods, the mixed powder is dispersed in water, an aqueous solution or a solvent, and then naturally dried, heat dried, freeze dried, spray dryer or the like. This is a method of obtaining a mixed powder by performing a drying treatment by the spray drying method of 1. This mixed powder has a characteristic that the abrasive grains and the resin can be uniformly mixed, and a uniform composition can be easily obtained even in the formed fixed abrasive grains, and a preferable molded powder can be obtained. Also in this case, it is possible to control the average particle size and particle size distribution suitable for handling and molding by using a spray dryer or other spray drying and selecting drying conditions, that is, operating conditions of the drying device. For example, average particle size 1
It is desirable that the powder has a size of ˜500 μm, preferably 10 to 100 μm, and more preferably 30 to 80 μm.

In the fourth method, a slurry type abrasive liquid containing water and / or an aqueous solution and / or a solvent and / or a binder and / or a chemical is added to the abrasive grains as needed, butadiene styrene, polybutadiene, or Acrylic rubber MBS
A resin powder and, if necessary, water or an aqueous solution or a solvent are added, mixed or mixed and dispersed, and dried by a spray drying method including natural drying, heat drying, freeze drying or a spray dryer to obtain a mixed powder. Also in this case, a spray dryer or other spray drying can be used for the above reason to control the average particle size and particle size distribution suitable for handling and molding. For example, it is desirable that the powder has an average particle size of 1 to 500 μm, preferably 10 to 100 μm, and more preferably 30 to 80 μm. The most desirable method of mixing the raw materials of the grindstone is to mix the slurry-like abrasive particles and the liquid (latex) MBS resin, and then spray-dry with a spray dryer to granulate. In this way, uniform mixing of the slurry and MBS resin can be achieved. It should be noted that even if the abrasive grains are not in the form of a slurry, the slurry is previously in a low temperature (room temperature to 2
Even if it is supplied in the form of abrasive particles in the form of primary particles that have been spray-dried by a spray dryer at (00 ° C.), it can be uniformly mixed with the MBS resin.

In the fifth method, when the butadiene styrene, polybutadiene, or acrylic rubber-based MBS resin raw material is in the form of an aqueous solution or an emulsion, dry powder treatment is performed, and then the dry powder is mixed with the abrasive grain powder and dry mixed. There is a way to get the powder. Further, after further dispersing in water or an aqueous solution or a solvent, if necessary, a binder and / or a chemical agent is added and a mixed powder is obtained by drying or dry pulverization treatment, whereby the abrasive grains, the resin and the additive are uniformly mixed. There is a feature that can be done.
In that case, it is possible to obtain a preferable molding powder in which it is easy to obtain a uniform composition even in the molded fixed abrasive.

In the sixth method, when the butadiene styrene, polybutadiene, or acrylic rubber-based MBS resin raw material is in the form of an aqueous solution or emulsion, the abrasive grain raw material in the form of abrasive grains or a slurry is used as needed in water or an aqueous solution. Alternatively, a solvent is added to mix or mix and disperse the dry abrasive particles which have been dry powder treated, and then further dispersed in water or an aqueous solution or solvent, and then a binder and / or a chemical agent is added if necessary, and mixed by a dry or dry pulverization process. It is a method of obtaining powder. In this case also, there is a feature that the abrasive grains and the resin and the additive can be uniformly mixed,
In addition, it is possible to obtain a preferable molding powder in which a uniform composition can be easily obtained even in the fixed abrasive grains that have been molded. In addition, it is possible to dry and mix in the molding die used for the following molding method and to fill the raw material in the die at the same time, which is preferable because the manufacturing process is shortened.

Next, a description will be given of the forming of this raw material powder by heating and pressure forming into a fixed-abrasive polishing tool. In this molding, since the MBS resin is a thermoplastic resin, the MBS resin is softened only by heating, and therefore the raw material powder can be molded into the mold and heated. At this time, the mold does not have to be pressurized, but it is preferable to perform the process while applying pressure in order to control the shape of the fixed-abrasive polishing tool after molding or control the porosity. In order to obtain the required size and porosity when forming the fixed-abrasive polishing tool, it is preferable to use a die having a stopper structure so that the volume does not become infinitely small during pressurization. With this stopper structure,
Molding by pressure is not carried out and molding by constant volume is carried out, so that a fixed shape and porosity can be given to the fixed abrasive polishing tool. After heating and pressure molding, the flat surface and outer diameter are processed, and after being formed into a predetermined shape, it is used for polishing.
Further, since the fixed-abrasive polishing tool has a flat plate shape, and the structure and material are easily deformed and swelled by moisture, sufficient moisture is given to the fixed-abrasive polishing tool during shape processing, etc., and an unbalanced moisture balance does not occur. Such consideration is necessary.

Next, an example of a specific method of manufacturing a fixed-abrasive polishing tool using cerium oxide abrasive grains and MBS resin as a binder material will be described. For example, the fixed abrasive polishing tool has a molding size of 55 cm in diameter and 5 mm or more in thickness. As for the volume ratio of the abrasive powder before molding and the binder powder, 29 to 49% (preferably 34 to 44%) are abrasive particles, and the remaining 51 to 71% (preferably 56 to 66%).
Is the binder powder. As the grindstone material, in addition to the abrasive grains and the binder, an additive such as a surfactant or a polishing aid, an elastic body such as rubber may be added, or the binder material may be used by mixing two or more kinds of resins. The volume composition ratio of the fixed abrasive polishing tool thus prepared is 25 to 45% (preferably 30 to 40%) for abrasive grains, 45 to 65% (preferably 50 to 60%) for binder, and 0 for voids. ˜20% (preferably 5 to 15%), for example, abrasive grains: binder:
The target value is vacancy = 35: 55: 10. The MBS resin is a thermoplastic resin, and the molding temperature is preferably about 150 to 200 ° C.

The drying treatment may be natural drying or heat drying, but it is preferable to use a spray dryer as shown in FIG. After the raw material is heated and dried by a spray dryer and the MBS resin, which is a thermoplastic resin, is once melted,
Dry into spheres or lumps with depressions. Therefore, the raw materials are uniformly mixed before and after the spray dryer treatment, and the handling becomes easy. It is preferable to mix all the raw materials before filling the mold. When the raw material is supplied to the mold in a liquid state and molded, when performing heat and pressure molding, the water content evaporates, and the fixed abrasive grains are formed while water is contained, or
Alternatively, since the voids after the evaporation of water produce non-uniform bubbles and voids, uniform and desired fixed abrasive grains cannot be obtained. Therefore, it is preferable to supply the raw material to the molding jig in a dry powder form.

The dry powdering treatment with a spray dryer is performed as follows. In the spray-drying method, abrasive grains or a raw material such as MBS resin powder is diffused in water or a solvent and sufficiently dispersed by application of ultrasonic waves to form a suspension of fine particles. Then, the suspension of fine particles is supplied to the space where the hot air is spirally rotating. As a result, the liquid portion of the suspension is momentarily dried, and the fine particles form an aggregate while increasing the surface area per unit volume. By using, for example, abrasive grains of about 0.3 μmφ as the fine particles, it is possible to perform spherical granulation, which is an aggregate of the fine abrasive grains of about 5 to 100 μmφ. According to this spray drying method, many steps such as concentration, filtration, pulverization, classification and drying can be instantaneously performed at once, and it is possible to easily granulate from fine particles into a lump-like aggregate. . The particle size after granulation (particle size after polymerization) has a desirable particle size depending on the molding method, and when hot pressing is used, the range is preferably 1 to 1000 μm, and more preferably 5 to 1000 μm.
The range is preferably 500 μm, more preferably 10 to 200 μm. This particle size is the spray dryer operating conditions such as hot air temperature, atomizer shape, atomizer rotation speed, hot air exhaust air amount, exhaust air temperature, and viscosity of the spray dryer supply liquid when the spray dryer method is used for drying and granulation. It is possible to adjust the solid content concentration and the stock solution supply rate.

FIG. 6 shows an example of a spray dryer suitable for granulation by the above spray drying method. Hot air is blown into the spray dryer body 31 from the pipe 37, and a spiral flow 43 is formed in the body 31. As hot air, air is blown from a blower 34 via an air filter 33, and hot air heated by a heater 35 is supplied into the main body 31 via a filter 36. From the atomizer 32, a suspension of fine abrasive grains is supplied into the hot air that is rotating in a spiral shape, whereby the abrasive grain aggregate is formed as described above. The granulated abrasive grain aggregate is stored in the container 42a at the bottom of the main body.
It enters, is sorted by a cyclone 39 through a pipe 38, enters a chamber 42b below it, or is sorted by a bag filter 40 and enters a chamber 42c below it. The hot air that has passed through the bag filter 40 is discharged by the air blower 41.

Next, the forming process of the fixed-abrasive polishing tool will be described with reference to FIG. First, as shown in (a), after combining the die 71 and the lower punch 72,
Fixed abrasive grain polishing tool raw material powder 73, which is a mixed powder of abrasive grain powder and resin powder, is put in and filled so as not to become non-uniform. Next, as shown in (b), the upper punch 74 is placed so that no load is applied, or a jig is set at a pressure sufficiently lower than a predetermined pressure molding pressure, and the glass transition point of the resin is exceeded, and thermal decomposition is performed. Predetermined molding temperature (eg 15
Heat to 0-300 ° C). Then, a sufficient time (for example, 5
Hold for ~ 30 minutes). Next, the upper punch 74 is thereafter pressurized to a target volume as shown in (c). On this occasion,
By using a molding jig having a stepped stopper structure 75 as shown in (b), it is possible to pressurize to a predetermined volume.

During the hardening of the fixed abrasive grain, pressure is applied so as to spread laterally by the pressure from above, so the die adheres to the fixed abrasive raw material. Therefore, by removing the spacer below the die from the middle, the die can move integrally with the fixed abrasive grain raw material, distortion does not occur at the peripheral portion of the hardened fixed abrasive grain, and the fixed abrasive grain body The density becomes uniform. Also, insert a spacer under the die 71 at the beginning, pressurize with a pressure sufficiently smaller than the molding pressure, and then remove the spacer.
Further, a jig may be used for forming by a step of pressurizing with a forming pressure. Although molding can be performed by a method that does not use spacers, it is preferable to use it for the purpose of relaxing internal stress of the molded product and uniformity of density. Furthermore, this pressure is applied to the upper punch 7
Pressure control may be performed by position control of No. 4. After a lapse of a predetermined time, it is preferably naturally cooled, and gradually cooled to a temperature sufficiently lower than the glass transition point, and then deframed to obtain a fixed abrasive polishing tool 73A. Note that the jig may be manufactured by a process controlled by time, temperature, and pressure, without using a jig having a stopper structure as shown in the drawing.

After the fixed-abrasive polishing tool has been molded, the product is subjected to external shape / planar processing. Since this fixed-abrasive polishing tool does not have sufficient strength, it may be cracked or broken when it is transported or fixed to a machine, so that it is fixed to the pedestal. For fixing to the pedestal (adhesion, adhesion, mechanical fixing, etc.),
It can be carried out during the molding of the fixed abrasive polishing tool, but it is preferably carried out after the molding when the thermal expansion coefficient is different or when the deterioration of the material may occur. It is preferable that the fixed-abrasive polishing tool has a thickness from the viewpoint of wear reduction, but a thin flat plate type may be used if the wear is small during use. When a fixed-abrasive polishing tool is used for polishing, it is often used for polishing while supplying water or liquid. Therefore, since there is a problem of swelling of the fixed-abrasive polishing tool, when fixing the pedestal and the fixed-abrasive polishing tool, it is preferable to fix the fixed-abrasive polishing tool in a state in which the fixed-abrasive polishing tool is swollen to some extent, which is close to the state of use. That is, the liquid is soaked into the fixed abrasive polishing tool so that it is swollen with the same liquid as when it is used, and the fixed abrasive polishing tool itself is bonded and fixed to the pedestal in a stable size and shape. However, it is preferable to maintain that state until the time of use.

The manufacturing process of a typical fixed abrasive grain polishing tool is as follows. A slurry containing CeO ₂ abrasive grains having an average particle diameter of 0.165 μm and a fine dispersion of MBS resin are mixed and dried by a spray dryer. After granulating to obtain a granulated product having an average particle size of 45 μm having a particle size distribution in the range of 9 to 200 μm, the granulated product is filled in a mold having a diameter of about 560 mm and heated and compressed at a heating temperature of about 200 ° C. with a hot press machine. Perform molding. Further, after adhering to a base (cartridge plate for attaching to the CMP apparatus table) with an adhesive, a grindstone is manufactured through outer diameter processing and flat processing of a polishing action surface.

Next, the glass transition point of the thermoplastic resin will be examined. First, it is necessary that the polishing tool has sufficient strength during polishing. Therefore, the glass transition point Tg needs to be room temperature (20 to 25 ° C.) or higher. Then, in a state where the polishing tool does not come into contact with the object to be polished, the polishing tool needs to maintain its brittle property (brittleness), and it is necessary that the resin does not turn into fine grinding dust and hinder the polishing. Therefore, the glass transition point Tg also needs to be room temperature or higher. Further, if the resin is softened even at room temperature, the polishing surface becomes too soft when coming into contact with the object to be polished (for example, a semiconductor wafer), and the flatness of the object to be polished cannot be obtained. In addition, when the resin has fluidity, it is likely to aggregate together with the abrasive grains to easily form an aggregate. Therefore, it is desirable that only the outermost surface of the contact portion with the object to be polished is softened during polishing. Normally, when polishing the surface of a semiconductor wafer, the temperature of the polishing surface is 6
It reaches about 0 ° C. From such a viewpoint, the glass transition point Tg of the resin forming the polishing tool is preferably 60 ° C. or higher. Furthermore, if the glass transition point Tg is too low, mold release becomes difficult due to the moldability of the polishing tool during manufacturing. From this point of view, the glass transition point Tg is preferably 50 ° C. or higher. Furthermore, if molding at a relatively low temperature is possible,
Productivity is improved and cost can be reduced. From the viewpoint of manufacturing such a polishing tool, the glass transition point Tg is preferably 200 ° C. or lower. Judging the above comprehensively,
The glass transition point Tg of the resin forming the polishing tool is higher than room temperature and preferably 200 ° C. or lower.

By the way, resin materials generally exhibit hydrophobicity.
Because of this, the polishing abrasive liquid (slurry) is retained on the pad surface during polishing
It's hard to do. Therefore, in order to perform stable polishing, the dresser
A process called singing (seasoning) is required.
That is, the pad surface is thinly cut with a diamond file and polished.
By eliminating polishing scraps and fluffing the surface,
This is a process to increase the surface area and make it easier to hold the slurry.
It If the pad itself is hydrophilic, increase the surface area
No need for extra dressing process for polishing
Since it only needs to be removed, the dressing cost of the pad is small
Therefore, long-term use becomes possible. For materials that exhibit hydrophilicity
Is -CO-OH, -OH, -NH_Two, -NHCONH
_Two,-(OCH_TwoCH_Two) Materials with hydrophilic groups such as n-
Everything is covered. Also, generally oxygen, nitrogen, sulfur, etc.
The group containing the element is a hydrophilic group, especially when salt is being formed.
In this case, it becomes a strongly hydrophilic group, which is very suitable. Strongly hydrophilic
The base is -SO_ThreeH, -SO_ThreeM, -OSO_ThreeH, -O
SO_ThreeM, -COOM, -NR _ThreeX (M: Alkali metal
Or-NH_FourR: alkyl group, X: halogen), etc.
It Add the above hydrophilic substances to the resin that constitutes the polishing pad.
Or adding hydrophilicity to the resin itself, that is, modifying
By doing so, slurry can be easily applied to the pad surface during polishing.
A polishing pad that can be held is obtained.

The technique of uniformly mixing the abrasive grains and the resin in the liquid can be applied to the thermosetting resin. As examples, examples in which a liquid phenol resin and ceria slurry and a liquid phenol resin and silica slurry are mixed will be described. If the thermosetting resin is a powdery solid, it is dissolved or finely dispersed in an organic solvent such as ethanol or methanol to form a liquid resin. The solvent may be water. If the liquid resin has a high viscosity, it is similarly dissolved or dispersed in pure water or an organic solvent such as ethanol. This work is important in order to make it possible to uniformly disperse when mixing with the abrasive grains which is the subsequent work. Although the dispersion method is dispersion with a stirrer, other methods such as ultrasonic dispersion may be used, or a combination of a plurality thereof may be used. Generally, the effect of uniform dispersion is high when a stirrer and an ultrasonic disperser are used together.

If the abrasive grains are also powdery solids, they are dissolved or finely dispersed in an organic solvent containing pure water or ethanol. If it is a slurry-like polishing liquid, the viscosity is lowered as it is or by diluting it. As the dispersion method, the same method as the resin can be used. The slurry-like polishing liquid and the liquid resin are mixed after adjusting the viscosity to the same level. If either one of the viscosities is too high and uniform mixing is difficult, dilute with water or another solvent to adjust the viscosity to the same level and then mix to obtain a slurry-like abrasive liquid containing abrasive grains. And liquid resin are mixed uniformly. The liquid resin is an emulsion, rubber emulsion, or suspension in which the resin is dispersed or dissolved in water or another solvent.

The liquid thermosetting resin and the slurry-like abrasive liquid are mixed and uniformly mixed and dispersed. Also in this case, the dispersion method used in combination with the same ultrasonic disperser as described above can be used. Further, the dispersion treatment may be performed only when the thermosetting resin liquid and the abrasive liquid are not separately dispersed, but only when the two are mixed.

The mixed solution produced in the above operation is subjected to a spray dryer or other spray drying treatment, dried and granulated to obtain a powdery mixture. The mixture obtained above is uniformly filled in a mold and subjected to heat and pressure treatment for molding. At this time, since the present mixture is a powder in which the thermosetting resin and the abrasive particles are uniformly mixed, the mixing ratio of the abrasive particles and the thermosetting resin does not collapse during the mold filling. Therefore, uniform filling can be easily performed.

The mold is composed of upper and lower dies and spacers shown in FIG. Since the thermosetting resin hardens after heating, constant pressure molding may be used. In this case, after pressurizing with a low pressure, the spacer is removed, and the die is floated, and further pressure heat molding is performed. After a lapse of a predetermined time, cooling, deframed,
Get the whetstone.

After molding, flat surface outer diameter processing is performed to prepare a predetermined shape, which is then used for polishing. In addition, since the fixed-abrasive polishing tool has a flat plate shape, and the structure and material are easily deformed and swelled by moisture, sufficient moisture is given to the fixed-abrasive polishing tool during shape processing so that an unbalanced moisture balance does not occur. Careful consideration is required. In the mixing of the abrasive particles and the resin in the liquid, the powdery abrasive particles and the liquid phenol resin may be mixed in the liquid and then spray-dried by spray drying to prepare a mixed granulated powder.

FIG. 8 is a plan view showing an arrangement configuration of each part of the polishing apparatus mainly for polishing a semiconductor wafer according to the embodiment of the present invention. The above-mentioned fixed-abrasive polishing tool or polishing pad of the present invention is used in this polishing apparatus. The polishing apparatus shown in FIG. 8 has a wafer cassette 21 for stocking a large number of semiconductor wafers.
It is equipped with four load / unload stages 22 for mounting. The load / unload stage 22 may have a mechanism capable of moving up and down. A transfer robot 24 having two hands on a traveling mechanism 23 so that each wafer cassette 21 on the load / unload stage 22 can be reached.
Are arranged.

The lower hand of the two hands of the transfer robot 24 is used only when receiving a semiconductor wafer from the wafer cassette 21, and the upper hand is used only when returning the semiconductor wafer to the wafer cassette 21. . This is an arrangement in which the clean wafer after cleaning is placed on the upper side and the wafer is not contaminated further. The lower hand is a suction-type hand that vacuum-sucks a wafer, and the upper hand is a drop-type hand that holds the peripheral edge of the wafer. The suction type hand conveys accurately regardless of the displacement of the wafer in the cassette, and the drop type hand does not collect dust unlike the vacuum suction type, so that the back side of the wafer can be kept clean. Two cleaning machines 25 and 26 are arranged on the opposite side of the wafer cassette 21 with the traveling mechanism 3 of the transfer robot 24 as the axis of symmetry. The washing machines 25 and 26 are arranged at positions where the hand of the transfer robot 24 can reach. A wafer station 70 having four semiconductor wafer mounting bases 27, 28, 29, 30 is arranged at a position reachable by the robot 24 between the two cleaning machines 25, 26. The washing machine 25, 2
6 has a spin dry function of rotating the wafer at a high speed to dry the wafer, whereby the two-stage cleaning and 3 of the wafer are performed.
It is possible to deal with step cleaning without replacing the module.

The washing machines 25 and 26 and the mounting tables 27 and 2
Area B in which 8, 29, 30 are arranged and area A in which the wafer cassette 21 and the transfer robot 24 are arranged.
A partition wall 84 is arranged to separate the cleanliness of the above, and a shutter 31 is provided at an opening portion of the partition wall for transporting a semiconductor wafer between the regions. Washing machines 25 and 3
A transfer robot 80 having two hands is arranged at a position where the two mounting tables 27, 29, 30 can be reached, and two cleaning robots 26 and three mounting tables 28, 29, 30 are provided at two positions. A transfer robot 81 having a hand is arranged.

The mounting table 27 is used to transfer semiconductor wafers between the transfer robot 24 and the transfer robot 80, and is provided with a semiconductor wafer presence / absence detection sensor 91. The mounting table 28 is used to transfer a semiconductor wafer between the transfer robot 24 and the transfer robot 81, and includes a semiconductor wafer presence / absence detection sensor 92. The mounting table 29 is used to transfer a semiconductor wafer from the transfer robot 81 to the transfer robot 80, and includes a sensor 93 for detecting the presence or absence of a semiconductor wafer and a rinse nozzle 95 for preventing the semiconductor wafer from drying or cleaning it. . The mounting table 30 is used to transfer the semiconductor wafer from the transfer robot 80 to the transfer robot 81, and is provided with a sensor 94 for detecting the presence or absence of the semiconductor wafer and a rinse nozzle 96 for preventing the semiconductor wafer from drying or cleaning it. . The mounting tables 29 and 30 are arranged in a common waterproof cover, and a shutter 97 is provided at the transport cover opening.
Is provided. The mounting table 29 is located on the mounting table 30, and the wafer after cleaning is placed on the mounting table 29 and the wafer before cleaning is placed on the mounting table 30 to prevent contamination due to the fall of the rinse water. Note that in FIG. 8, the sensors 91, 9
2, 93, 94, rinse nozzles 95, 96, and shutter 97 are shown schematically, and their positions and shapes are not shown accurately.

The upper hands of the transfer robot 80 and the transfer robot 81 are used to transfer the once cleaned semiconductor wafer to the cleaning machine or the mounting table of the wafer station 70, and the lower hand is cleaned once. It is used to transfer unsemiconductor wafers and semiconductor wafers before polishing. By taking the wafer in and out of the reversing machine with the lower hand, the upper hand is not contaminated by the rinsing water dripping from the upper wall of the reversing machine. A washing machine 82 is arranged adjacent to the washing machine 25 at a position reachable by the hand of the transfer robot 80. Further, the cleaning machine 83 is arranged at a position where the hand of the transfer robot 81 can reach so as to be adjacent to the cleaning machine 26. The cleaning machines 25, 26, 82, 83, the mounting tables 27, 28, 29, 30 of the wafer station 70 and the transfer robots 80, 81 are all located in the area B and lower than the atmospheric pressure in the area A. It is adjusted to atmospheric pressure.
The cleaning machines 82 and 83 are cleaning machines capable of cleaning both sides.

This polishing apparatus has a housing 66 so as to surround each device, and the inside of the housing 66 is divided into a plurality of chambers (area A, partition wall 85, partition wall 86, partition wall 87, and partition wall 67). (Including area B). The partition 87 forms a polishing chamber which is separated from the region B, and the polishing chamber further includes the partition 6
It is divided into two regions C and D by 7. In each of the two areas C and D, two polishing tables and one top ring for holding one semiconductor wafer and polishing while pressing the semiconductor wafer against the polishing table are arranged. . That is, the polishing tables 54 and 56 are provided in the area C, and the polishing table 5 is provided in the area D.
5, 57 are arranged, a top ring 52 is arranged in the region C, and a top ring 53 is arranged in the region D. Further, a polishing liquid nozzle 60 for supplying a polishing polishing liquid to the polishing table 54 in the area C and a dresser 58 for dressing the polishing table 54 are arranged. A polishing liquid nozzle 61 for supplying a polishing polishing liquid to the polishing table 55 in the region D, and the polishing table 55.
And a dresser 59 for performing dressing. Further, a dresser 68 for dressing the polishing table 56 in the area C and a dresser 69 for dressing the polishing table 57 in the area D are arranged. A wet type wafer film thickness measuring machine may be installed instead of the polishing tables 56 and 57. In that case, the film thickness of the wafer immediately after polishing can be measured, and it is possible to increase the number of wafers and control the polishing process for the next wafer by utilizing the measured value.

The wafer transferred to the top rings 52 and 53 is sucked by the vacuum suction mechanism of the top ring, and the wafer is conveyed to the polishing table 54 or 55 while being sucked. Then, the wafer is the polishing table 5
Polishing is performed with a polishing surface composed of the polishing pad of the present invention or a fixed-abrasive polishing tool mounted on 4, 55. By using the polishing pad or the fixed-abrasive polishing tool of the present invention, it is possible to obtain a good polished surface with few scratches even in the single-step polishing. In FIG. 6, the second polishing tables 56 and 57 described above are arranged at positions where the top rings 52 and 53 can reach each other. As a result, after the wafer is completely polished by the first polishing tables 54 and 55,
The polishing pads for finishing attached to the second polishing tables 56, 57 can be used for finish polishing. On the finishing table, deionized water is finished while supplying pure water or a chemical solution containing no abrasive grains to a polishing pad such as SUBA400 or Polytex (both made by Rodel Nitta), or polishing is performed by supplying slurry. . Depending on the type of film attached to the semiconductor wafer, after polishing with the second polishing tables 56 and 57, the first polishing table 5
It may be processed at 4,55. In this case, since the polishing surface of the second polishing table has a small diameter, a fixed-abrasive polishing tool, which is more expensive than a polishing pad, is attached and rough-cut, and then the life of the large-diameter first polishing table is reduced. Running costs can be reduced by applying a polishing pad that is shorter than a fixed-abrasive polishing tool and performing final polishing. In this way, by using the first polishing table as the polishing pad and the second polishing table as the fixed-abrasive polishing tool, an inexpensive polishing table can be supplied. The price of fixed-abrasive polishing tools is higher than that of polishing pads,
The larger the diameter, the higher the height. Further, the life of the polishing pad is shorter than that of the fixed-abrasive polishing tool, so that the life is extended by carrying out a light load such as finish polishing. Further, if the diameter is large, the contact frequency can be dispersed and the life is extended. Therefore, the maintenance cycle is extended and the productivity is improved.

FIG. 9 is a diagram showing a main part of the polishing apparatus. This polishing apparatus includes a polishing table 56 (57) equipped with a fixed-abrasive polishing tool 117 having a fixed-abrasive polishing tool 115 having a diameter of about 60 cm attached to a disk 116 instead of a polishing pad on the surface, and abrasive grains during polishing. And a liquid supply nozzle 110 for supplying water or a chemical liquid W containing no water. Here, the fixed-abrasive polishing tool 117 fixes the fixed-abrasive polishing tool 115 mainly composed of a thermoplastic resin such as ABS resin or MBS resin of the present invention to the metal or ceramic disk 116 using an adhesive. It was done. The fixed-abrasive polishing tool 117 then clamps the polishing mechanism 56, 119 to the polishing table 56 (57).
It is fixed easily and surely by using. Wafer polishing conditions are, for example, “wafer surface pressure: 300 g / cm ² , rotation speed: table / wafer = 30/35 min ⁻¹ , liquid supply amount: 200 cc / min, liquid type: pure water (1 wt%
The following surfactants are included) ". In addition, "wafer surface pressure:
500 g / cm ² , rotation speed: table / wafer = 25 /
10 min ⁻¹ , liquid supply amount: 200 cc / min, liquid type: pure water (containing 1 wt% or less of surfactant).

The structure of the top ring 101 and the like for holding the other polishing object 104 is similar to that of the other polishing tables 54, 5
The same as 5. The water or the like is supplied onto the polishing surface of the fixed-abrasive polishing tool 115 for the purpose of lubricating the polishing surface during polishing and cooling for removing heat generated by polishing. As an example, in this case, about 200 ml / min of water is supplied. As water, ultrapure water containing no impurities may be used. An alkaline solution or the like may be used instead of water.

The semiconductor wafer 104 to be polished is
While being pressed against the fixed abrasive polishing tool 115 by the top ring 101 via the elastic mat 102, the drive shaft 108
Is driven to rotate. On the other hand, the fixed-abrasive polishing tool 11
The polishing table 56 (57) to which 5 is fixed is also independently driven to rotate, where the surface to be polished of the semiconductor wafer 104 comes into contact with the surface of the fixed abrasive polishing tool 115 and slides to proceed with polishing. In the subsequent finishing process, pure water (or a chemical liquid containing no abrasive grains) is used to perform a cleaning / finishing process with a soft polishing pad.

Next, a specific example of fixing the fixed-abrasive polishing tool to which the fixed-abrasive polishing tool is attached to the rotary surface plate will be shown. Figure 1
0 indicates that the fixed abrasive polishing tool is fixed to the surface plate by the clamp method. The fixed-abrasive polishing tool 115 is fixed to a metal disk 116 made of an aluminum material or the like by sticking, and constitutes a fixed-abrasive polishing tool 117. Polishing table 56
The clamp mechanism 118 is provided at (57), and the movable portion 119 of the clamp mechanism 118 fixes the outer peripheral portion of the fixed abrasive polishing tool 117. Therefore, the movable part 1
The fixed-abrasive-polishing tool 117 with the fixed-abrasive-polishing tool 115 affixed to the polishing table 56 (5
7) By placing it on the surface and closing the movable part 119, the fixed abrasive polishing tool 117 can be fixed to the polishing table 56 (57) by the spring mechanism of the movable part. Further, the fixed abrasive grain polishing tool 117 is moved to the polishing table 56 by rotating the movable portion 119 from the closed position to the opened position.
It can be removed from (57).

FIG. 11 shows another fixing method for fixing the fixed abrasive polishing tool to the surface plate. The fixed-abrasive polishing tool 115 is fixed to a metal disk 116 with a collar made of an aluminum material or the like by sticking, and constitutes a fixed-abrasive polishing tool 117.
The flange portion 117A of the fixed-abrasive-grain polishing tool 117 is fixed to the polishing table 56 (57) by bolting the clamp 132. That is, using four clamps as shown in the drawing, each clamp 132 fastens the flange portion 117A of the fixed-abrasive polishing tool 117 to the screw hole provided in the polishing table 56 (57) by the bolt 133. It is fixed by. As shown in the figure, the clamp 132 has a relatively wide arc-shaped structure, and the angle formed with respect to the center of both ends of the arc is set to 44 °.
The brim portion 1 of the fixed-abrasive polishing tool 117 using one bolt
17A is fixed by being sandwiched between the surfaces of the polishing table 56 (57). Therefore, the fixed abrasive polishing tool 117 can be easily attached to and detached from the polishing table 56 (57) by attaching and detaching the bolt 133. It should be noted that the reason why the relatively wide clamp is used is that the outer peripheral portion of the fixed-abrasive polishing tool 117 is fixed to the polishing table 56 (5) by the clamp.
Since it is fixed to 7), it is for preventing the fixed abrasive polishing tool 115 from being deflected by being pressed against the polishing surface.

Further, four protrusions 135 are provided in total on the outer peripheral portion of the flange 117A of the metal disk constituting the fixed abrasive polishing tool 117. Each projection 135 is provided with a screw hole 136 so that a suspension bolt or a push bolt 137 can be fastened. Hanging bolt 13
No. 7 is provided for facilitating the handling of the fixed-abrasive polishing tool 117 because it has a considerable weight when the fixed-abrasive polishing tool 117 is replaced.
Further, the screw hole 136 is also used for inserting the push bolt 137 in order to peel off the fixed abrasive polishing tool 117 that is in close contact with the polishing table 56 (57). That is, the polishing table 56 (5
7) When removing from the screw hole, push the bolt 137 into the screw hole 1
By inserting into 36 and rotating, push bolt 137
When the tip of the fixed abrasive polishing tool 117 comes into contact with the surface of the rotary platen and further rotates, the fixed abrasive polishing tool 117 is moved to the polishing table 56 (5).
It can be peeled off from 7). The polishing table 56
A groove 138 is formed at a position (57) with respect to the screw hole 136. The groove 138 is a hanging bolt or push bolt 13
It plays the role of receiving the tip of 7.

In this embodiment, the clamp 132 is set to 4
Although four pieces of protrusions and four protrusions 135 are provided, the clamp may be formed in a ring shape so as to fix the entire circumference of the fixed-abrasive polishing tool in consideration of use conditions such as pressing load. good. Further, the number of protrusions may be appropriately increased or decreased in consideration of the weight of the fixed-abrasive polishing tool and the adhesion with the surface plate. As a material for the metal disk to which the fixed-abrasive polishing tool is attached, other than aluminum material, for example, stainless material, titanium or the like may be used in consideration of corrosion resistance, or resin or the like may be used.

FIG. 12 schematically shows a configuration example of a polishing apparatus using a polishing abrasive liquid (slurry). This device
The polishing table 54 (55) to which the polishing pad 121 using a thermoplastic resin such as ABS resin of the present invention is attached is provided. A top ring 101 that holds a semiconductor wafer 104 that is an object to be polished.
While 1 presses the semiconductor wafer 104 against the polishing pad 121, the semiconductor wafer 104 is rotated to slide on the surface to be polished of the semiconductor wafer 104 for polishing. Polishing pad 12
Slurry Q containing a large amount of polishing abrasive grains is supplied onto slurry 1 from slurry supply line 122. The surface to be polished of the semiconductor wafer 104 slides while pressing the polishing pad 121 in which the slurry containing a large amount of polishing abrasive grains is dispersed as described above.
The polishing of the surface to be polished proceeds. Top ring 101
Is a rotating shaft 10 via a ball bearing 111.
8 is tiltably held and rotates at a predetermined speed as the rotary shaft 108 rotates. The semiconductor wafer 104 is held in a guide ring 128 arranged on the peripheral portion of the top ring, and is pressed against the polishing pad 121 by the top ring 101 via the elastic film 102. Here, since the polishing pad is made of a thermoplastic resin such as ABS resin or MBS resin, it is possible to perform soft polishing without causing scratches or the like due to a temperature rise during sliding.
Further, by using a resin containing an elastic element contained in the resin component, it is possible to perform high-quality polishing that is hard in the macro and soft in the micro.

FIG. 13 shows a polishing apparatus according to another embodiment of the present invention. This polishing apparatus holds a semiconductor wafer 152 to be polished on a rotating holding unit 151, and similarly slides a rotating pellet-shaped fixed abrasive polishing tool. The pellet-shaped fixed abrasive polishing tool 155 has, for example, a diameter of about 20 mm and a thickness of about 5 mm, and four holders 153 are attached to the rotating holder 153. The holder 153 rotates about its axis 153c and presses the fixed-abrasive polishing tool 155 against the surface of the semiconductor wafer 152 to be polished, so that the polishing surface of the fixed-abrasive polishing tool 155 causes the semiconductor wafer 152 to be polished. Polishing progresses by sliding on the surface of. Here, the axis 153c of the holder 153 of the fixed-abrasive polishing tool is eccentric by the distance L with respect to the center 151c of the semiconductor wafer 152 to be polished so as to polish the entire surface of the semiconductor wafer to be polished. . In this embodiment, the semiconductor wafer has a diameter of 1
The eccentricity L is about 35 mm, targeting 50 mm or 200 mm.

Next, the polishing conditions of this polishing apparatus will be outlined with reference to examples. The rotation speed of the semiconductor wafer to be polished is 100 min ⁻¹ , and the rotation speed of the fixed abrasive holder is 25 min ⁻¹ . The wafer surface pressure is 390 g / cm ² . In the polishing test using resin pellets, about 3 cc of cerium oxide slurry (or surfactant-containing cerium oxide slurry) is supplied. Also,
The polishing test using the fixed-abrasive pellets may be performed under the condition that pure water (or pure water to which a surfactant is added) is similarly supplied at about 3 cc.

It should be noted that each of the above-described embodiments merely describes one mode of the preferred embodiment of the present invention, and various modifications can be made without departing from the spirit of the present invention. .

[0098]

As described above, according to the present invention, good flatness can be obtained by using a thermoplastic resin or a resin having an elastic element as the resin constituting the fixed abrasive polishing tool or the polishing pad. At the same time, it is possible to perform high-quality polishing with less scratches.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a configuration example of a fixed-abrasive polishing tool according to an embodiment of the present invention, in which (a) is a case where a thermoplastic resin is used and (b) is an elastic filler. This is the case when it is included.

FIG. 2 is a diagram attached to an explanation of injection molding.

FIG. 3 is a diagram schematically showing a configuration example of a polishing pad according to an embodiment of the present invention.

FIG. 4 is experimental data comparing fixed abrasive grains made of various resin materials with respect to (a) polishing rate and (b) defect amount.

FIG. 5 is experimental data comparing (a) polishing rate and (b) defect amount with polishing pads containing no abrasive grains.

FIG. 6 is a diagram showing an example of a spray dryer suitable for granulation by a spray drying method.

FIG. 7 is a diagram for explaining a method for manufacturing a fixed-abrasive polishing tool by heat compression molding.

FIG. 8 is a plan view showing an example of the overall configuration of a polishing device.

9A is a plan view and FIG. 9B is a cross-sectional view showing a main part of the polishing apparatus.

FIG. 10 is a cross-sectional view showing a fixing method for fixing a fixed abrasive polishing tool to a surface plate by a clamp method.

FIG. 11 is a perspective view showing another fixing method for fixing the fixed-abrasive polishing tool to the surface plate.

FIG. 12 is a cross-sectional view schematically showing a configuration example of a polishing device using a polishing / polishing liquid.

FIG. 13 is a diagram showing a polishing apparatus according to another embodiment of the present invention.

[Explanation of symbols] 1 Fixed abrasive polishing tool 2 pores or pore agents 3 Rubber particles or hollow particles 4 binder (resin) 5 Abrasive grains or aggregates 6 rubber particles 7 ABS resin or MBS resin 8 elastic elements 11 Injection hydraulic cylinder 12 Screw rotation hydraulic motor 13 heater 14 Check valve 15 Mold 16 cylinders 17 screw

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B24D 3/02 310 B24D 3/02 310A 3/32 3/32 C08J 5/14 CER C08J 5/14 CER C09K 3/14 550 C09K 3/14 550C 550D 550F 550J 550K H01L 21/304 622 H01L 21/304 622B 622F // C08L 55:02 C08L 55:02 (72) Inventor Wada Yutaka 11-11 Haneda Asahi-cho, Ota-ku, Tokyo EBARA CORPORATION (72) Inventor Nasunori Matsuo 11-1 Haneda Asahi-cho, Ota-ku, Tokyo F-term inside EBARA CORPORATION (reference) 3C058 AA07 AA09 CA01 DA02 DA12 DA17 3C063 AA10 AB05 BA22 BC03 BD01 CC30 EE10 EE26 FF23 4F071 AA12 AA12X AA13 AA22X AA34X AA77X AB03 AB18 AB21 AB26 AE13 AH19 BA01 BB05 BC06 BC07

Claims (31)

[Claims] 1. A polishing tool that performs polishing through abrasive grains by sliding while pressing an object to be polished, wherein the polishing tool is mainly composed of a thermoplastic resin. . 2. A polishing tool that performs polishing through abrasive grains by sliding while pressing an object to be polished, wherein the polishing tool is made of a plastic resin having hardness and elasticity existing in the resin. A polishing tool comprising an elastic element having the same. 3. The polishing tool is a fixed-abrasive polishing tool including abrasive grains in the polishing tool.
Or the polishing tool according to 2. 4. The polishing tool according to claim 1, wherein the polishing tool is a non-fixed abrasive grain polishing pad. 5. The abrasive grains are cerium oxide (CeO)._Two),
Alumina (Al_TwoO _Three), Silicon carbide (SiC), silicon oxide
Element (SiO_Two), Zirconia (ZrO_Two), Iron oxide (F
eO, Fe_ThreeO_Four), Manganese oxide (MnO_Two, Mn_Two
O_Three), Magnesium oxide (MgO), calcium oxide
(CaO), barium oxide (BaO), zinc oxide (Zn)
O), barium carbonate (BaCO_Three), Calcium carbonate
(CaCO_Three), Diamond (C), or a combination of these
The material according to claim 3, wherein the material is composed of a composite material.
On-board polishing tool. 6. The polishing tool according to any one of claims 1 to 5, wherein the polishing tool is formed by pressure injection into a predetermined mold by an injection molding method. 7. The polishing tool according to claim 1, wherein the resin contains an acrylonitrile butadiene styrene (ABS) resin. 8. The polishing tool according to claim 1, wherein the resin contains a core-shell type resin having an elastic body containing a rubber material as a core. 9. The polishing tool according to claim 8, wherein the resin is butadiene styrene, polybutadiene, or an acrylic rubber-based MBS resin. 10. The polishing tool according to claim 2, wherein the elastic element includes an elastic filler, and the elastic filler includes a rubber filler. 11. A surface active agent is further added to the material forming the polishing tool.
The polishing tool according to any one of 0. 12. A hydrophilic substance is further added to the material forming the polishing tool.
The polishing tool according to any one of 1. 13. A hydrophilic group is added (modified) to a material forming the polishing tool.
The polishing tool according to any one of 0. 14. A fixed-abrasive polishing tool for polishing via an abrasive by pressing and sliding an object to be polished, wherein the fixed-abrasive polishing tool is butadiene styrene, polybutadiene, or acrylic rubber-based MBS. A polishing tool containing a resin. 15. A method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, comprising filling a mixture of the raw materials into a forming jig, and forming by heating / cooling treatment and / or pressure treatment. A method for manufacturing a fixed-abrasive polishing tool, comprising: 16. An abrasive grain and a thermoplastic resin as raw materials,
A method for producing a fixed-abrasive polishing tool, characterized in that the abrasive powder and the thermoplastic resin are mixed before, during, or after the raw material is filled into a molding jig. 17. A method for producing fixed abrasives using abrasive grains and a thermoplastic resin as raw materials, wherein in the step of polymerizing or producing the thermoplastic resin, the abrasive grains or slurry and the raw material of the thermoplastic resin are mixed to form a dispersion liquid. A method for producing a fixed-abrasive polishing tool, which comprises producing a mixed polymer of a thermoplastic resin and abrasive grains in the dispersion liquid. 18. A method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, wherein the abrasive grains or slurry and the raw material of the thermoplastic resin are mixed to form a dispersion liquid, and the thermoplastic resin and the abrasive are mixed in the dispersion liquid. A method for producing a fixed-abrasive polishing tool, which comprises performing a spray dryer or a spray drying treatment after producing a mixed polymer of grains. 19. A method for producing fixed abrasives using abrasive grains and a thermoplastic resin as raw materials, wherein when the thermoplastic resin is polymerized or produced, a mixed polymer of the thermoplastic resin and the abrasive grains having a particle diameter of 1 to 500 μm. A method of manufacturing a fixed-abrasive polishing tool, comprising: 20. A method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, wherein the abrasive grain powder or slurry and the thermoplastic resin powder or emulsion liquid are mixed with water or a solvent before being filled in a molding jig. 16. The method for producing a fixed-abrasive polishing tool according to claim 15, wherein the mixed solution is mixed with and dispersed in, and the mixed solution is subjected to dry powder treatment. 21. A method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, wherein the abrasive grain powder or slurry is dried before being filled in a molding jig, and an emulsion of the dried product and the thermoplastic resin. The method for producing a fixed-abrasive polishing tool according to claim 15, wherein the liquids are mixed and dispersed, and the mixed liquid is subjected to dry powder treatment. 22. A method for producing fixed abrasive grains using abrasive grains and a thermoplastic resin as raw materials, wherein the abrasive grain powder or slurry is dried before being filled in a molding jig, and the dried product and the thermoplastic resin are dried. The method for producing a fixed-abrasive polishing tool according to claim 15, wherein the substance is dispersed again in water or a solvent, and the mixed liquid is subjected to dry powder treatment. 23. A method for producing fixed abrasive grains as a liquid raw material in which abrasive grains and a thermoplastic resin are mixed, in the step of drying the liquid raw material before filling in a molding jig,
19. A spray drying process is performed.
And a method for producing a fixed-abrasive polishing tool according to any one of 20 to 22. 24. Using abrasive grains and a thermoplastic resin as raw materials,
The method for producing a fixed abrasive grain by mixing these, wherein when the fixed abrasive grain raw material mixture is dried or after being dried, the powder is pulverized to a powder of 1 to 500 µm. And a method for manufacturing a fixed-abrasive polishing tool according to any one of 20 to 23. 25. A semiconductor wafer polishing apparatus comprising the polishing tool according to any one of claims 1 to 23. 26. A polishing method for polishing a semiconductor wafer using the polishing tool according to any one of claims 1 to 23. 27. A method of manufacturing fixed abrasives using abrasives and resin as raw materials, wherein the abrasives and the resin are mixed in a liquid before being filled in a molding jig, and the mixture of the abrasives and the resin is sprayed. A method for producing a fixed-abrasive polishing tool, characterized by performing a dryer or other spray-drying treatment, filling the dried mixture in a molding jig, and molding. 28. The method for manufacturing a fixed-abrasive polishing tool according to claim 27, wherein the abrasive grains are supplied by a slurry. 29. The method for manufacturing a fixed-abrasive polishing tool according to claim 27, wherein the resin is supplied in a liquid form. 30. A fixed-abrasive polishing tool having abrasive grains, a resin binding the abrasive grains, and holes, wherein a thermoplastic resin is used as the resin. 31. The composition ratio (vol%) of the fixed abrasive grains is 10% <abrasive grain ratio (Vg) <50% 30% <binder ratio (Vb) <80% 0% <porosity (Vp) The fixed-abrasive polishing tool according to claim 30, wherein <40%.