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CN-122008070-A - Polishing pad for chemical mechanical polishing and preparation method thereof

CN122008070ACN 122008070 ACN122008070 ACN 122008070ACN-122008070-A

Abstract

The invention belongs to the technical field of polishing pads, and particularly relates to a polishing pad for chemical mechanical polishing and a preparation method thereof, wherein the polishing pad is provided with a black soft plastic veneer layer, and the soft plastic veneer layer is a foaming body formed by a coating slurry formed by black coloring agent and polyurethane resin through a wet film forming method; the thickness of the foaming body is 0.3-2 mm at room temperature, the Shore hardness A is 5-50 degrees, and the basic pigment particles in the black coloring agent are fullerene. The polishing pad of the present invention has the property of preventing scratches on the surface of an object to be polished by the chemical mechanical polishing pad, and the number of scratches on the surface of the object to be polished is reduced.

Inventors

  • CHEN CHAOSHI
  • LIU XIANGBAO
  • WANG KAI

Assignees

  • 万华化学集团电子材料有限公司

Dates

Publication Date
20260512
Application Date
20241112

Claims (10)

  1. 1. A polishing pad for chemical mechanical polishing, characterized in that the polishing pad has a black soft plastic sheet layer, which is a foam formed by a wet film forming method from a coating slurry formed by a black colorant and a polyurethane resin; the thickness of the foam is 0.3 to 2mm, preferably 0.6 to 1.2mm, at room temperature.
  2. 2. The polishing pad according to claim 1, wherein the foam has a shore a hardness of 5 ° to 50 °, preferably 10 ° to 30 °.
  3. 3. The polishing pad according to claim 1 or 2, wherein the hard segment content of the polyurethane resin is 30 to 50wt%.
  4. 4. A polishing pad according to any one of claims 1 to 3, wherein the polyurethane resin has a 100% modulus of 5 to 10mpa, preferably 6 to 8mpa.
  5. 5. The polishing pad according to any one of claims 1 to 4, wherein the content of insoluble matter contained in the polyurethane resin is 0.01wt% or less.
  6. 6. The polishing pad of any one of claims 1-5, wherein the base pigment particles in the black colorant are fullerenes; Preferably, the fullerene is selected from one or more of C20, C60 and C70, more preferably C60.
  7. 7. The method of manufacturing a polishing pad according to any one of claims 1 to 6, comprising the steps of: a) Mixing polyurethane resin, colorant slurry containing black colorant, optional auxiliary agent and organic solvent to prepare coating slurry; b) Uniformly coating the coating slurry obtained in the step a) on a supporting layer with a certain thickness; c) Immediately immersing the support layer coated with the slurry into a coagulating bath for curing and forming; d) And c) washing the cured and molded product obtained in the step c), stripping the polishing layer from the supporting layer after washing, and drying the polishing layer to obtain the foam contained in the polishing pad.
  8. 8. The preparation method according to claim 7, wherein the coating slurry in the step a) comprises the following components in parts by mass, based on 100 parts by mass of the polyurethane resin: 10-20 parts of colorant slurry; 0-10 parts of auxiliary agent; 30-80 parts of organic solvent.
  9. 9. The method of claim 7 or 8, wherein the colorant slurry is a mixture of a black colorant and an organic solvent, wherein the mass ratio of the black colorant to the organic solvent is 40:60 to 60:40, preferably 40:60 to 50:50.
  10. 10. The preparation method according to any one of claims 7 to 9, wherein the organic solvent is selected from one or more of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone and methylethylketone, preferably N, N-dimethylformamide; the auxiliary agent is selected from a film forming auxiliary agent and/or a foaming control agent.

Description

Polishing pad for chemical mechanical polishing and preparation method thereof Technical Field The invention belongs to the technical field of polishing pads, and particularly relates to a polishing pad for chemical mechanical polishing and a preparation method thereof. Background Chemical Mechanical Polishing (CMP) is a process of planarizing a surface of a workpiece to be polished on a Polishing pad by organically combining the grinding action of nano-sized particles with the chemical etching action of a Polishing liquid. Chemical mechanical polishing has been widely used in planarization processes for semiconductor wafers, which are indispensable processing steps in the production of wafers for the manufacture of electronic components. The chemical mechanical polishing pad is used as a key consumable in the chemical mechanical polishing process, and utilizes a unique hole structure to transfer polishing liquid and remove scraps generated in the polishing process. In chemical mechanical polishing pads, soft polyurethane microporous polishing pads are typically used as finishing or final polishing to enable lower defectivity to the polishing material. The conventional black chemical mechanical polishing pad uses carbon black particles dispersed in dimethylformamide as a colorant to turn the chemical mechanical polishing pad into black, but the carbon black particles dispersed in dimethylformamide have problems of aggregation and sedimentation with the storage time of the colorant. Although this problem can be ameliorated using a filter device, the use of such aggregated colorants results in the unavoidable occurrence of large amounts of fine particles in the chemical mechanical polishing pad, which also results in the unavoidable occurrence of large amounts of fine scratches in the polished object being polished by the chemical mechanical polishing pad. Then, how to scratch the surface of the object to be polished by the chemical mechanical polishing pad is reduced, and improvement of the chemical mechanical polishing pad is inspired. Disclosure of Invention The invention aims to solve the technical problems of the prior black chemical mechanical polishing pad and provide a polishing pad for chemical mechanical polishing and a preparation method thereof, wherein the obtained polishing pad has the property of preventing a polished object from being scratched, which can prevent the polishing pad from generating a large amount of tiny particles in the chemical mechanical polishing and also prevent the polished object polished by the chemical mechanical polishing pad from generating a large amount of tiny scratches. In order to achieve the above object, the present invention provides the following technical solutions: In a first aspect, there is provided a polishing pad for chemical mechanical polishing, the polishing pad comprising a black soft plastic sheet layer, wherein the soft plastic sheet layer is a foam formed by a coating slurry of a black colorant and a polyurethane resin by a wet film forming method (i.e., the foam contains the black colorant); The thickness of the foam is 0.3 to 2mm (for example, 0.35mm, 0.4mm, 0.5mm, 0.65mm, 0.8mm, 0.9mm, 1.0mm, 1.05mm, 1.1mm, 1.15mm, 1.25mm, 1.4mm, 1.5mm, 1.6mm, 1.8 mm), preferably 0.6 to 1.2mm at room temperature. According to the polishing pad provided by the invention, in some embodiments, the Shore hardness A of the foam is 5-50 ° (e.g., 6 °, 8 °, 10 °, 12 °, 15 °,20 °, 25 °, 35 °, 40 °, 45 °), preferably 10-30 °. According to the polishing pad provided by the invention, in some embodiments, the hard segment content of the polyurethane resin is 30-50wt% (for example, 32wt%, 35wt%, 36wt%, 38wt%, 40wt%, 42wt%, 45wt%, 48 wt%). In some embodiments, the polyurethane resin has a 100% modulus of 5 to 10MPa (e.g., 5.5MPa, 7MPa, 7.5MPa, 8.5MPa, 9MPa, 9.5 MPa), preferably 6 to 8MPa. In some embodiments, the polyurethane resin is a solvent-based polyurethane resin having a solids content of 25-50wt%, e.g., 28wt%, 30wt%, 32wt%, 35wt%, 40wt%, 45wt%. In some embodiments, the polyurethane resin may contain an insoluble content of 0.01wt% or less (e.g., 0.009wt%, 0.008wt%, 0.006wt%, 0.005wt%, 0.004wt%, 0.002wt%, 0.001 wt%), and the insoluble content may be more than 0. The insoluble matter may include, for example, micro plastic particles, metal flakes, metal oxides, silicates, carbonates, and common dust such as human or animal hair or skin flakes, plant pollen, etc. According to some embodiments of the polishing pad provided herein, the base pigment particles in the black colorant are fullerenes. In some embodiments, the fullerene is selected from one or more of C20, C60 and C70, preferably C60. In a second aspect, there is provided a method of preparing the polishing pad described above, comprising the steps of: a) Mixing a polyurethane resin, a colorant slurry containing a black colorant, and optionally an auxiliary agent with an organic solvent to prepare a coating slu