JP2016140937A - Polishing pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing pad which has a long life cycle and is excellent in polishing efficiency.SOLUTION: A polishing pad 10 is a polishing pad for removing a metal film provided on the surface of a polishing object, and has a base material 11 and a polishing layer 12. The base material 11 has a first surface (surface 11a) facing the polishing object, and is formed of a material having voids. The polishing layer 12 has a curable resin film 121 which is selectively provided on the first surface, and polishing abrasive grains 122 which are fixed to the curable resin film 121 and come in contact with the metal film.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a polishing pad for removing a metal film provided on the surface of an object to be polished, for example.

  As a polishing pad used for lapping (rough polishing) or polishing of a semiconductor material, a metal material, or a difficult-to-cut material, one having a structure in which abrasive grains are fixed on a substrate such as a nonwoven fabric is known. The abrasive grains are typically fixed to the base material by a curable resin or the like impregnated in the base material.

  For example, Patent Document 1 discloses an abrasive sheet in which a nonwoven fabric is impregnated with a binder in which abrasive grains are dispersed. Further, Patent Document 2 discloses a polishing tape having surface irregularities in which abrasive grains are adhered on a film substrate by an electrostatic spray method.

JP 2008-194761 A JP 2002-172563 A

In recent years, polishing pads having excellent polishing efficiency and a long life cycle have been demanded. For example, when the polishing pad is used for removing a metal film provided on the surface of an object to be polished, the polishing surface is likely to be clogged by polishing scraps of the metal film, and there is a problem that the life cycle is short. .
For example, the configuration described in Patent Document 1 has a problem that the polishing efficiency is small because most of the abrasive grains sink into the nonwoven fabric. In addition, in the configuration described in Patent Document 2, the unevenness formed on the surface of the base material is intended to prevent clogging to a certain extent. There is a problem.

  In view of the circumstances as described above, an object of the present invention is to provide a polishing pad having a long life cycle and excellent polishing efficiency.

In order to achieve the above object, a polishing pad according to one embodiment of the present invention is a polishing pad for removing a metal film provided on the surface of an object to be polished, and includes a substrate and a polishing layer. .
The substrate has a first surface facing the object to be polished, and is made of a material having a gap.
The polishing layer includes a curable resin film selectively provided on the first surface, and polishing abrasive grains fixed to the curable resin film and in contact with the metal film.

  In the above polishing pad, a polishing layer containing polishing abrasive grains is selectively provided on the surface of the base material, so that a large number of polishing abrasive grains are distributed on the surface of the base material and constitute a polishing pad having high polishing characteristics. can do. Moreover, since the base material is made of a material having voids, the voids inside the base material serve to receive polishing scraps. As a result, even if the metal is sticky and easily clogged, the life cycle can be improved while ensuring good polishing efficiency.

  The polishing layer is formed, for example, by applying an abrasive-containing solution containing a curable resin and abrasive grains to the first surface and curing the curable resin. According to this configuration, since the curable resin soaks into the base material made of a material having voids and the abrasive grains remain on the base material surface, a large number of abrasive grains are distributed on the base material surface, and high polishing characteristics are obtained. It can be set as the polishing pad which has.

  The space of the base material may be provided in such a size that the curable resin before curing can pass therethrough and the abrasive grains cannot pass therethrough. Thereby, many abrasive grains can be efficiently distributed on the substrate surface.

  The polishing pad may further include a sheet material made of a curable resin material. In this case, the base material further includes a second surface opposite to the first surface, which is bonded to the sheet material. As a result, moderate elasticity is imparted to the polishing pad, so that the polishing conditions can be optimized according to the type of the object to be polished.

  The constituent materials of the base material and the abrasive grains are not particularly limited, and can be appropriately selected depending on the object to be polished. When removing the metal film on the surface of the object to be polished, typically, a nonwoven fabric is used for the substrate, and diamond abrasive grains are used for the abrasive grains.

  The metal film on the surface of the object to be polished is not particularly limited, and may be, for example, a refractory metal film such as metal molybdenum. Even such a metal film can be polished efficiently. Moreover, the structure etc. which have a molybdenum film | membrane on the surface may be sufficient, for example, the said polishing pad can be used suitably for the manufacturing process of a solar cell panel.

  The average particle diameter of the abrasive grains, the content ratio of the abrasive grains with respect to the curable resin film, and the like are not particularly limited, and can be appropriately selected according to the object to be polished. By setting the average grain size of the abrasive grains to 10 μm or more and 40 μm or less and the content ratio being 10 wt% or more and 40 wt% or less, for example, the molybdenum film on the surface of the polishing object can be efficiently removed.

  According to the present invention, a polishing pad having good polishing efficiency and life cycle can be provided.

1 is a perspective view of a polishing pad according to a first embodiment of the present invention. It is sectional drawing of the same polishing pad. It is sectional drawing of the base material with which the polishing pad is provided. It is a schematic diagram of the abrasive grain containing solution used for manufacture of the polishing pad. It is a schematic diagram which shows the manufacturing method of the same polishing pad. It is a schematic diagram which shows the manufacturing method of the same polishing pad. It is a perspective view of the polishing pad which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the same polishing pad. 2 is an SEM image of a cross section of a polishing pad according to Example 1. FIG. It is a SEM image of the surface of the polishing pad. 4 is a SEM image of a cross section of a polishing pad according to Example 2. It is a SEM image of the surface of the polishing pad. 4 is a SEM image of a cross section of a polishing pad according to Comparative Example 1. It is a SEM image of the surface of the polishing pad. 4 is a SEM image of a cross section of a polishing pad according to Comparative Example 1. It is a SEM image of the surface of the polishing pad. It is a figure which shows the experimental result when a metal film is ground using the polishing pad which concerns on Example 3. FIG. It is a figure which shows the experimental result when a metal film is ground using the other polishing pad which concerns on Example 3. FIG. It is an experimental result which shows the mode before and behind implementation of the purification process of the polishing pad which concerns on Example 3. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
[Configuration of polishing pad]
FIG. 1 is a schematic perspective view showing a polishing pad 10 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the polishing pad 10. FIG. 3 is a cross-sectional view of the substrate 11.

  The polishing pad 10 includes a base material 11 and a polishing layer 12.

  The base material 11 is comprised with the material which has a sheet-like space | gap. As shown in FIG. 3, the base material 11 has a front surface 11 a (first surface) and a back surface 11 b (second surface), and is composed of a nonwoven fabric 112 impregnated with a synthetic resin 111.

Examples of the method for producing the nonwoven fabric 112 include a spun bond method, a thermal bond method, a chemical bond method, a needle punch method, and a spun lace method. In this embodiment, since the nonwoven fabric 112 functions also as a cushion layer, a thick nonwoven fabric is preferable and the needle punch method was used. 100~5000g / ^{m 2} as the basis weight of the nonwoven fabric 112, preferably 0.05~0.60g / cm ³ as the density, and more preferably 0.10~0.50g / cm ^3. Moreover, 0.01-10 dtex can be used as the fineness of the fiber used for a nonwoven fabric. When the density is the same, the void unit can be adjusted by changing the number of fibers per unit volume by changing the fineness of the fibers. The voids of the nonwoven fabric 112 can be adjusted by the basis weight, density, and fiber fineness, and the porosity is preferably about 45 to 95%.

  In the present invention, the void is a continuous space inside the base material, which allows the curable resin applied to the surface of the base material to penetrate into the base material, and the abrasive grains applied to the base material surface. It makes it possible to keep the majority on the substrate surface. If it is such a space | gap, the magnitude | size will not be ask | required, For example, it represents with the magnitude | size of the inscribed circle in one cross section of a space | gap, and it is preferable that it is 1-100 micrometers. If the gap is smaller than 1 μm, it is difficult for the curable resin to penetrate into the nonwoven fabric 112, and if the gap is larger than 100 μm, the abrasive grains may pass through the gap.

  The synthetic resin 111 is for bonding fibers constituting the nonwoven fabric 112 and is partially impregnated between the fibers.

  By impregnating the non-woven fabric 112 with the synthetic resin 111, the synthetic resin 111 holds the non-woven fabric 112 and gives the polishing pad 10 elasticity suitable for polishing, and at the same time, the porosity and the void size of the base material 11 can be controlled. It becomes. The synthetic resin 111 may be a polyurethane resin, for example, and the nonwoven fabric 112 may be a nonwoven fabric made of polyester fibers, for example.

  Moreover, the base material 11 is not restricted to said thing, What is necessary is just a material which has a moderate space | gap. For example, it may be a non-woven fabric, a woven fabric or a knitted fabric which is made of a foamable material such as a foamed polyurethane foam having continuous foaming, or is not impregnated with a synthetic resin. The thickness of the substrate 11 is not particularly limited, and can be about several mm to several tens mm.

  The surface 11a of the base material 11 is a surface on which the polishing layer 12 is formed, and the back surface 11b of the base material 11 may be provided with an adhesive tape or an adhesive layer (not shown) as necessary.

  The polishing layer 12 includes a curable resin film 121 that is selectively provided on the surface 11 a of the substrate 11, and polishing abrasive grains 122 that are fixed to the curable resin film 121. As will be described later, the polishing layer 12 has an abrasive-containing solution (abrasive abrasive-containing resin solution) containing a curable resin material constituting the curable resin film 121 and abrasive grains 122 on the surface 11a of the substrate 11. It is applied and formed by curing the curable resin material.

  The curable resin film 121 fixes the abrasive grains 122 to the base material 11. The curable resin material constituting the curable resin film 121 is not particularly limited as long as it can be cured, and may be a thermosetting resin, a photocurable resin, a two-component mixed curable resin, or the like. be able to. For example, the curable resin material may be either a synthetic resin or a natural resin, and examples of the synthetic resin include phenol resins, epoxy resins, urethane resins, acrylic resins, and PVA (polyvinyl alcohol). In addition, examples of natural resins include glue. As the curable resin material, these listed resin simple substances may be used, or a mixture thereof may be used.

  When the curable resin material is applied to the surface 11 a as the abrasive grain-containing solution, the curable resin material soaks into the base material 11, and a part thereof is contained in the base material 11. The depth at which the curable resin material penetrates is not particularly limited, and may penetrate to the back surface 11b.

The abrasive grains 122 are fixed on the substrate 11 by a curable resin film 121. The abrasive grains 122 are particles with high hardness, and can be, for example, abrasive grains (diamond abrasive grains) made of diamond. In addition, the abrasive grains 122 are abrasives made of silicon carbide (SiC), alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), zirconium silicate (ZrSiO ₄ ), cerium oxide (CeO ₂ ), or the like. It may be a grain. Although the particle size of an abrasive grain is not specifically limited, For example, the magnitude | size which does not pass the space | gap of the nonwoven fabric 112 is preferable.

  The average particle diameter of the abrasive grains, the content ratio of the abrasive grains with respect to the curable resin film, and the like are not particularly limited, and can be appropriately selected according to the object to be polished. By setting the average grain size of the abrasive grains to 10 μm or more and 40 μm or less and the content ratio being 10 wt% or more and 40 wt% or less, for example, a metal film (for example, a molybdenum film) on the surface of the polishing object can be efficiently removed.

  The polishing pad 10 has the above configuration. As shown in FIG. 1, the polishing pad 10 has a disk shape, and its size (diameter) is determined according to the size of the polishing apparatus, and can be, for example, about several cm to 1 m in diameter. Further, the shape of the polishing pad 10 is not limited to a disk shape, but may be a rectangular shape, a polygonal shape, a belt-like shape that can be attached to a roller, or the like.

[Production method of polishing pad]
Next, a method for manufacturing the polishing pad 10 will be described.

  As shown in FIG. 4, an abrasive-containing solution S containing abrasive grains is prepared. The abrasive grain-containing solution S includes a resin mixed solution R and abrasive grains 122. The resin mixed solution R contains various curable resins and solvents that constitute the curable resin film 121.

  The solvent is used to adjust the viscosity of the abrasive-containing solution S. For example, water, isopropyl alcohol, isobutyl alcohol, 1-butanol, 2-butanol, isopentyl alcohol, methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, Tert-butyl acetate, sec-butyl acetate, isopentyl acetate, 2-methoxyethyl acetate, 2-ethoxyethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, 1,3-dioxolane, 1,4-dioxane, ethylene glycol monomethyl ether, ethylene glycol Monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether and the like are used.

  The viscosity of the abrasive-containing solution is adjusted so that the time for the resin mixed solution R to soak into the nonwoven fabric 112 is shorter than the time until the solvent evaporates and the curing starts. Specifically, the viscosity is preferably about 0.1 Pa · s to 100 Pa · s. Moreover, you may add dispersing agents, such as surfactant, in order to improve the dispersibility of the abrasive grain in an abrasive grain containing solution as needed.

  Subsequently, as shown in FIG. 5, the abrasive-containing solution S is applied to the surface 11 a of the substrate 11. The coating method is not particularly limited, and various coating methods such as a doctor blade method, a roll coating method, a spin coating method, a gravure coating method, a screen printing method, and a rotary printing method are applicable. After application, as shown in FIG. 6, a part of the resin mixed solution R soaks into the base material 11, and the abrasive grains 122 remain on the surface 11a.

  Subsequently, volatile components such as a solvent contained in the abrasive grain-containing solution S are removed by heating or decompression, and the abrasive grain-containing solution S is dried. After drying, the curable resin film 121 is formed by curing the curable resin contained in the abrasive grain-containing solution S. For example, when the curable resin film 121 is a thermosetting resin, the abrasive grain-containing solution S can be cured by heating. Further, when the curable resin film 121 is a photocurable resin, it can be cured by irradiating the abrasive-containing solution S with light (for example, ultraviolet rays). By the curing of the curable resin film 121, the polishing layer 12 is formed on the substrate 11 (see FIG. 2).

  In the polishing pad 10 produced as described above, the polishing abrasive grains 122 are unevenly distributed on the surface 11a (polishing surface) of the substrate 11, and a large number of polishing abrasive grains 122 are exposed on the surface 11a. Therefore, many polishing abrasive grains 122 can be brought into contact with the object to be polished, so that the polishing efficiency of the object to be polished can be increased.

  In general, when most of the abrasive grains are present in the substrate, only a few abrasive grains are exposed on the polishing surface, and therefore improvement in polishing efficiency cannot be expected. Further, this type of polishing pad is not of a type in which a new surface can be used for polishing even if it is worn by polishing, and is replaced when the initial polishing surface is worn. For this reason, the abrasive grains present inside the substrate are wasted, and the diamond abrasive grains are expensive, and it has been difficult to produce a polishing pad with high polishing efficiency at a low cost.

  On the other hand, in the polishing pad 10 according to the present embodiment, almost the entire amount of the polishing abrasive grains 122 contained in the abrasive grain-containing solution S can be exposed from the surface (polishing surface) of the substrate 11. It is possible to reduce the required amount of polishing abrasive grains 122. Therefore, in the polishing pad 10 of this embodiment, it is possible to reduce the manufacturing cost while improving the polishing efficiency.

  Furthermore, according to the polishing pad 10 of this embodiment, since the base material 11 is made of a material having voids and has a plurality of voids inside, the polishing debris generated during polishing of the surface of the object to be polished is removed from the polishing layer. 12 can be accommodated in the void inside the substrate 11. For this reason, clogging of the surface of the polishing layer 12 is suppressed, and it is possible to provide the polishing pad 10 with excellent durability that does not depend on the material of the object to be polished.

In particular, when the object to be polished is a metal or a metal film that covers the surface of the object, it is common that polishing dust is more viscous than an oxide material or the like. Even in such a case, according to the polishing pad 10 of the present embodiment, since the life cycle can be lengthened, the replacement frequency is low, and therefore the efficiency of the polishing process can be improved.
The polishing pad 10 of this embodiment can also be applied when the object to be polished is a composite of different materials such as a laminate of a metal film and a nonmetal film. According to this embodiment, for example, a laminate in a desired region can be easily removed from a solar power generation panel in which an electrode film, a photoelectric conversion layer (semiconductor layer), and the like are stacked on a glass substrate. .

  Furthermore, according to the present embodiment, for example, by blowing compressed air injected from an air gun onto the polishing surface, it is possible to easily remove the polishing debris accumulated in the gap inside the substrate 11. As a result, the used polishing pad 10 can be regenerated, and the life cycle of the polishing pad 10 can be further improved.

(Second embodiment)
Subsequently, a polishing pad according to a second embodiment of the present invention will be described.

  FIG. 7 is a perspective view of the polishing pad 200 according to the present embodiment, and FIG. 8 is a cross-sectional view of the polishing pad 20. As shown in FIG. 8, the polishing pad 20 includes a base material 11, a polishing layer 12, and a resin sheet 13.

  Since the structure of the base material 11 and the polishing layer 12 is the same as that of the above-mentioned first embodiment, the description thereof is omitted here.

  The resin sheet 13 is a sheet made of synthetic resin, and is bonded to the back surface 11 b of the base material 11. The resin sheet 13 can be made of polyethylene terephthalate resin. Further, the resin sheet 13 may be made of other synthetic resin. The thickness of the resin sheet 13 is not particularly limited, and can be about several mm to several tens of mm.

  As the base material 11, a thin nonwoven fabric having a thickness of 0.03 to 0.30 mm manufactured by a spunlace method was used. In the present embodiment, since the resin sheet 13 functions as a cushion layer, the base material 11 only needs to exhibit a function of allowing the thermosetting resin to pass therethrough and not passing the abrasive grains. The base material 11 can be a nonwoven fabric made of, for example, polyethylene terephthalate fiber.

  The base material 11 is not limited to the above, and may be any material having an appropriate gap. For example, it may be a non-woven fabric, a woven fabric or a knitted fabric made of a foamable material such as a foamed polyurethane foam or a synthetic resin.

  Also in the polishing pad 20 of the present embodiment configured as described above, the same operational effects as those of the first embodiment can be obtained. According to the present embodiment, by laminating the resin sheet 13 on the back surface 11 b of the base material 11, the resin sheet 13 can support the base material 11 and can impart elasticity suitable for polishing to the polishing pad 20. is there.

  The polishing pad which concerns on the Example and comparative example of this invention was produced, and the polishing surface and the cross section were observed with the scanning electron microscope (SEM).

  A phenolic resin (PS-F (manufactured by J-Chemical)) and an epoxy resin (K-1430 (manufactured by J-Chemical)) are mixed at a weight ratio of 1: 1 to obtain an abrasive-containing solution. The containing solution and the solvent (IPA) were mixed at a weight ratio of 9: 1 to prepare a resin mixed solution. Diamond abrasive grains (TMD-S 20-25 (particle size: about 18 μm, manufactured by Trustwell)) were added to the resin mixed solution to prepare an abrasive-containing solution. The amount of abrasive grains added was 40 wt% with respect to the resin weight.

  The above abrasive-containing solution was applied to the following various substrates and heated at 70 ° C. for 30 minutes to remove the solvent. Subsequently, the resin was cured by heating at 130 ° C. for 20 minutes to cause a crosslinking reaction.

Example 1
A polyester nonwoven fabric impregnated with a polyurethane resin was used as a base material, and an abrasive-containing solution was applied to the surface of the base material to prepare a polishing pad. FIG. 9 is an SEM image of a cross section of the polishing pad according to Example 1, and FIG. 10 is an SEM image of the surface (polishing surface) of the polishing pad.

  As shown in FIG. 9, the base material B and the polishing layer P were observed in the cross section of the polishing pad. A part of the resin mixed solution contained in the abrasive-containing solution was impregnated into the base material B, and as shown in the figure, a curable resin derived from the abrasive-containing solution was observed in the base material B. As shown in FIGS. 9 and 10, the abrasive grains are included in the polishing layer P and are present on the surface of the polishing pad. On the other hand, the abrasive grains are not present inside the base material B.

(Example 2)
A resin sheet made of polyethylene terephthalate resin was laminated on a base material made of polyethylene terephthalate nonwoven fabric. An abrasive-containing solution was applied to the surface of the nonwoven fabric to prepare a polishing pad. FIG. 11 is an SEM image of a cross section of the polishing pad according to Example 2, and FIG. 12 is an SEM image of the surface of the polishing pad.

  As shown in FIG. 11, resin sheet B1, nonwoven fabric B2, and polishing layer P were observed in the cross section of the polishing pad. A part of the resin mixed solution contained in the abrasive-containing solution was impregnated into the nonwoven fabric B2, and as shown in the figure, a curable resin derived from the abrasive-containing solution was observed in the nonwoven fabric B2. As shown in FIGS. 11 and 12, the abrasive grains are included in the polishing layer P and exist on the surface of the polishing pad. On the other hand, the abrasive grains are not present inside the base material B.

(Comparative Example 1)
Using a resin sheet made of polyethylene terephthalate resin as a base material, an abrasive-containing solution was applied to the surface of the base material to prepare a polishing pad. 13 is an SEM image of a cross section of the polishing pad according to Comparative Example 1, and FIG. 14 is an SEM image of the surface of the polishing pad.

  As shown in FIG. 13, the base material B and the resin layer T were observed in the cross section of the polishing pad. The resin mixed solution contained in the abrasive grain-containing solution is not impregnated into the base material B, and forms a resin layer T. The abrasive grains are buried in the resin layer T and hardly exist on the surface of the resin layer T as shown in FIGS.

(Comparative Example 2)
A surface of a polyester nonwoven fabric was treated with a primer, and a polishing pad was prepared by applying an abrasive-containing solution to the surface of the substrate. FIG. 15 is an SEM image of a cross section of the polishing pad according to Comparative Example 2, and FIG. 16 is an SEM image of the surface of the polishing pad.

  As shown in FIG. 15, the base material B and the resin layer T were observed in the cross section of the polishing pad. The resin mixed solution contained in the abrasive grain-containing solution is not impregnated into the base material B, and forms a resin layer T. The abrasive grains are buried in the resin layer T and hardly exist on the surface of the resin layer T as shown in FIGS. 15 and 16.

  As described above, in Examples 1 and 2, the base material was impregnated with the resin mixed solution to obtain a polishing pad having abrasive grains on the surface. For this reason, high polishing characteristics can be obtained. On the other hand, the abrasive grains are not present in the base material, and the abrasive grains contained in the resin mixed solution are prevented from being wasted.

  On the other hand, in Comparative Examples 1 and 2, the abrasive grains are not present in the substrate, but are buried in the resin layer formed by the resin mixed solution. For this reason, these polishing pads do not have polishing characteristics due to abrasive grains and do not function as polishing pads.

(Example 3)
As described below, samples of a plurality of polishing pads having the same structure as in Example 1 were prepared by changing the count (particle size) and the applied amount (weight ratio with respect to the curable resin film) of the abrasive grains. Each sample had a circular shape with a diameter of 20 mm.
Sample 1: Count # 800 (particle size 18 μm), applied amount 20 wt%
Sample 2: Count # 800 (particle size 18 μm), applied amount 30 wt%
Sample 3: Count # 800 (particle size 18 μm), applied amount 40 wt%
Sample 4: Count # 400 (particle size 36 μm), applied amount 20 wt%
Sample 5: Count # 400 (particle size 36 μm), applied amount 30 wt%
Sample 6: Count # 400 (particle size 36 μm), applied amount 40 wt%

  As an object to be polished, a Mo (molybdenum) film having a thickness of about 100 to 1000 nm formed on the surface of a glass substrate by a DC sputtering method was prepared, and the surface of the Mo film was polished using each sample. As a polishing method, the polished surface of the sample was brought into contact with the Mo film, and the sample was reciprocated in the uniaxial direction while pressing the back surface of the sample with a finger. As polishing conditions, the polishing pressure was about 100 kPa, and the number of polishing times (the number of reciprocations) was 15.

  17 shows the type of abrasive grains of each sample, the lower left side of FIG. 17 shows the state of the Mo film before polishing and the polished surface of each sample, and the lower right side of FIG. The state of the polished surface of each sample is shown. In each figure at the bottom of FIG. 17, the polished surfaces of the six samples indicated by circles are arranged in order of samples 1 to 6 from left to right, and the figure on the right side at the bottom of FIG. Shown in the lower region of each sample.

  As shown in FIG. 17, a constant polishing or grinding effect could be recognized for the Mo film for all of Samples 1 to 6. Focusing on Samples 1 to 3, it was confirmed that, even with the same number of abrasive grains, the grinding ability with respect to the Mo film increases as the applied amount of abrasive grains increases (the white area indicates the underlying substrate and the gray area) Indicates that the Mo film remains). Further, as shown in Samples 4 to 6, it was confirmed that the same grinding ability (Mo film removal ability) can be obtained by using # 400 abrasive grains.

  Moreover, from the result of FIG. 17, it was confirmed that the Mo film on the substrate can be ground and removed by the polishing pads according to Samples 3 to 6. Therefore, the molybdenum film can be efficiently removed by setting the average grain size of the abrasive grains to 10 μm to 40 μm and the content ratio of the abrasive grains to the curable resin film to 10 wt% to 40 wt%. Was confirmed.

  In addition, the present inventors have confirmed that a certain polishing ability with respect to the Mo film can be obtained even when the content of the abrasive grains is less than 20 wt%. FIG. 18 shows a state in which the Mo film surface was polished under the above-described polishing conditions using samples of 5 wt% (left side) and 10 wt% (right side), respectively.

  FIG. 19 shows the state of the polished surface of each sample when the polished surface of each sample after polishing is subjected to a purification treatment with an air gun (injection pressure of about 0.6 MPa). In the figure, the left side shows the state before purification, and the right side shows the state after purification. Note that the diagram on the left side of FIG. 19 corresponds to the diagram on the right side of FIG.

  As shown in FIG. 19, the effect of removing polishing debris from the polished surface was similarly recognized for each sample. That is, it was confirmed that the polished surface can be regenerated, and that the life cycle can be improved.

  As mentioned above, although embodiment of this invention was described, this invention is not limited only to the above-mentioned embodiment, Of course, a various change can be added.

  For example, in the above embodiment, the Mo film is taken as an example of the metal film that is an object to be polished. However, the present invention is not limited to this, and the present invention is applicable to grinding and removal of other non-ferrous metal films or iron metal films. Applicable. In addition to the metal film, the present invention can be applied to grinding a metal compound film such as a metal oxide or a ceramic film.

  Further, the content of the abrasive grains 122 with respect to the curable resin film 121 is not limited to the above-described range, and can be appropriately changed according to the object to be polished, the purpose of polishing, and the like.

  Further, the polishing pads 10 and 20 configured as described above are typically mounted and used on a head portion that can rotate or revolve, but in this case, they may be used alone or in a slurry state. The auxiliary abrasive may be used in combination.

DESCRIPTION OF SYMBOLS 10, 20 ... Polishing pad 11 ... Base material 12 ... Polishing layer 13 ... Resin sheet 111 ... Synthetic resin 121 ... Curable resin film 122 ... Polishing abrasive grain

Claims (8)

A polishing pad for removing a metal film provided on the surface of a polishing object,
A substrate having a first surface facing the object to be polished and made of a material having voids;
A polishing pad comprising: a curable resin film selectively provided on the first surface; and a polishing layer having polishing abrasive grains fixed to the curable resin film and in contact with the metal film. The polishing pad according to claim 1,
The polishing layer is formed by applying an abrasive-containing solution containing a curable resin and abrasive grains to the first surface and curing the curable resin. The polishing pad according to claim 1 or 2,
The gap of the substrate is provided with a size that allows the curable resin before curing to pass therethrough and prevents the abrasive grains from passing therethrough. The polishing pad according to any one of claims 1 to 3,
Further comprising a sheet material made of a synthetic resin material,
The said base material further has a 2nd surface on the opposite side to the said 1st surface joined to the said sheet | seat material. Polishing pad. The polishing pad according to any one of claims 1 to 4,
The substrate is a nonwoven;
The polishing pad is a diamond abrasive. A polishing pad according to any one of claims 1 to 5,
The metal film includes a molybdenum film. The polishing pad according to claim 6,
The polishing object is a solar power generation panel having the metal film formed on a surface thereof. A polishing pad according to any one of claims 5 to 7,
The average particle size of the abrasive grains is 10 μm or more and 40 μm or less,
The polishing pad having a content ratio of the abrasive grains to the curable resin film of 10 wt% or more and 40 wt% or less.