Search

EP-4742300-A1 - SLURRY AND POLISHING METHOD

EP4742300A1EP 4742300 A1EP4742300 A1EP 4742300A1EP-4742300-A1

Abstract

A slurry contains abrasive grains and water, in which the abrasive grains include cerium oxide particles, and a product P of a ratio R of a peak intensity of a (200) plane to a peak intensity of a (111) plane in an X-ray diffraction measurement of the cerium oxide particles and a crystallite diameter D of the (111) plane of the cerium oxide particles is 7.5 to 11.0 nm. A polishing method includes a step of polishing a surface to be polished using the slurry.

Inventors

  • MAEDA, MASANORI
  • SAKAGUCHI, Junya
  • KUBOTA, Shigeki
  • TAINAKA, Sota
  • MIZUTANI, MAKOTO

Assignees

  • Resonac Corporation

Dates

Publication Date
20260513
Application Date
20240529

Claims (9)

  1. A slurry comprising abrasive grains and water, wherein the abrasive grains comprise cerium oxide particles, and a product P of a ratio R of a peak intensity of a (200) plane to a peak intensity of a (111) plane of the cerium oxide particles in an X-ray diffraction measurement and a crystallite diameter D of the (111) plane of the cerium oxide particles is 7.5 to 11.0 nm.
  2. The slurry according to claim 1, wherein the ratio R is 0.220 to 0.330.
  3. The slurry according to claim 1, wherein the ratio R is 0.265 or more.
  4. The slurry according to claim 1, wherein the crystallite diameter D is 25.0 to 35.0 nm.
  5. The slurry according to claim 1, wherein the product P is 8.5 to 10.0 nm.
  6. The slurry according to claim 1, wherein a content of the abrasive grains is 0.01 to 10.00 mass%.
  7. The slurry according to claim 1, wherein a pH of the slurry is less than 7.00.
  8. The slurry according to claim 1, wherein the slurry is used for polishing a surface to be polished comprising silicon oxide.
  9. A polishing method comprising a step of polishing a surface to be polished using the slurry according to any one of claims 1 to 8.

Description

Technical Field The present disclosure relates to a slurry, a polishing method, and the like. Background Art In recent years, processing techniques for densification and micronization are becoming more important in manufacturing steps for semiconductor elements. A chemical mechanical polishing (CMP) technique that is one of processing techniques has become an essential technique in manufacturing steps for semiconductor elements for formation of shallow trench isolation (hereinafter, referred to as "STI"), flattening of pre-metal insulating materials or interlayer insulating materials, formation of plugs or embedded metal wirings, or the like. Examples of the most frequently used polishing liquid include a silica-based polishing liquid containing silica (silicon oxide) particles such as fumed silica or colloidal silica as abrasive grains. The silica-based polishing liquid is characterized by being high in versatility, and can polish broad types of materials irrespective of insulating materials and conductive materials by appropriately selecting an abrasive grain content, a pH, additives, or the like. On the other hand, a demand for a cerium oxide-based polishing liquid containing cerium oxide particles as abrasive grains is expanding. For example, the cerium oxide-based polishing liquid can polish an insulating material at a high rate even when a content of abrasive grains is lower than that in the silica-based polishing liquid (for example, see Patent Literatures 1 and 2 described below). Citation List Patent Literature Patent Literature 1: Japanese Unexamined Patent Publication No. H10-106994Patent Literature 2: Japanese Unexamined Patent Publication No. H08-022970 Summary of Invention Technical Problem Meanwhile, in recent years, a 3D-NAND device in which a cell portion of the device is stacked in a vertical direction has emerged. In the present technique, the level differences of the insulating materials during cell formation are several times higher compared to the conventional planar types. According to this, in order to maintain the throughput of the device production, it is necessary to rapidly resolve the high level difference as described above in a CMP step or the like, and it is necessary to improve a polishing rate for the insulating material. An aspect of the present disclosure is to provide a slurry capable of obtaining a high polishing rate for an insulating material. Another aspect of the present disclosure is to provide a polishing method using the slurry. Solution to Problem The present disclosure relates to the following [1] to [9] and the like. [1] A slurry containing abrasive grains and water, in which the abrasive grains include cerium oxide particles, anda product P of a ratio R of a peak intensity of a (200) plane to a peak intensity of a (111) plane in an X-ray diffraction measurement of the cerium oxide particles and a crystallite diameter D of the (111) plane of the cerium oxide particles is 7.5 to 11.0 nm.[2] The slurry according to [1], in which the ratio R is 0.220 to 0.330.[3] The slurry according to [1] or [2], in which the ratio R is 0.265 or more.[4] The slurry according to any one of [1] to [3], in which the crystallite diameter D is 25.0 to 35.0 nm.[5] The slurry according to any one of [1] to [4], in which the product P is 8.5 to 10.0 nm.[6] The slurry according to any one of [1] to [5], in which a content of the abrasive grains is 0.01 to 10.00 mass%.[7] The slurry according to any one of [1] to [6], in which a pH of the slurry is less than 7.00.[8] The slurry according to any one of [1] to [7], in which the slurry is used for polishing a surface to be polished containing silicon oxide.[9] A polishing method including a step of polishing a surface to be polished using the slurry according to any one of [1] to [8]. Advantageous Effects of Invention According to an aspect of the present disclosure, it is possible to provide a slurry capable of obtaining a high polishing rate for an insulating material. According to another aspect of the present disclosure is to provide a polishing method using the slurry. Description of Embodiments Hereinafter, embodiments of the present disclosure will be described in detail. <Definitions> In the present specification, a numerical range indicated using "to" indicates a range including numerical values described before and after "to" as a minimum value and a maximum value, respectively. "A or more" of the numerical range means A and a range exceeding A. "A or less" of the numerical range means A and a range less than A. In the numerical range described in stages in the present specification, an upper limit value or a lower limit value of a numerical range of a certain stage can be arbitrarily combined with an upper limit value or a lower limit value of a numerical range of another stage. In the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with