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DE-112024002490-T5 - Polishing pad, polishing process and process for manufacturing a semiconductor

DE112024002490T5DE 112024002490 T5DE112024002490 T5DE 112024002490T5DE-112024002490-T5

Abstract

The present invention relates to a polishing pad with a polishing layer having a circular polishing surface, wherein the polishing layer has one or more grooves α, each having a first end Eα1 and a second end Eα2, which is closer to the outer circumference of the polishing surface than the first end Eα1, and each extending from the first end Eα1 to the second end Eα2, wherein the first end Eα1 of each groove α is located in a region (1) which is a region of 70.0 to 99.0% of the radius of the polishing surface from the center of the polishing surface, and wherein the second end Eα2 of each groove α is not connected to the outer circumference of the polishing layer; and a polishing method in which the polishing pad is used.

Inventors

  • Azusa SUNAYAMA

Assignees

  • KURARAY CO., LTD.

Dates

Publication Date
20260513
Application Date
20240611
Priority Date
20230612

Claims (15)

  1. Polishing pad comprising a polishing layer with a circular polishing surface, wherein the polishing layer has at least one groove α having a first end Eα1 and a second end Eα2, which is closer to the outer circumference of the polishing surface than the first end Eα1, and which extends from the first end Eα1 to the second end Eα2, whereby the first end Eα1 of the groove α is located in a region (1) which is a region of 70.0 to 99.0% with respect to a radius of the polishing surface from a center point of the polishing surface, whereby the second end Eα2 of the groove α is not connected to the outer circumference of the polishing layer.
  2. Polishing pad after Claim 1 , wherein the first end Eα1 of the groove α is located in a range of 70.0 to 95.0% relative to the radius of the polishing surface from the center of the polishing surface.
  3. Polishing pad after Claim 1 or 2 , wherein the second end Eα2 of the groove α is located in a range of 85.0 to 99.9% relative to the radius of the polishing surface from the center of the polishing surface.
  4. Polishing pad after one of the Claims 1 until 3 , where the number of slots α is 2 to 36.
  5. Polishing pad after one of the Claims 1 until 4 , where the groove α has a linear shape.
  6. Polishing pad after one of the Claims 1 until 5 , wherein the polishing layer further comprises a reference recess β, wherein the reference recess β is a spiral, annular or grid-shaped reference groove β1 or reference holes β2 with a plurality of holes.
  7. Polishing pad after Claim 6 , wherein the polishing layer has the reference groove β1 and the groove α intersects the reference groove β1 at at least one point.
  8. Polishing pad after Claim 6 or 7 , wherein the groove α has a depth that is 0.5 to 2.5 times the depth of the reference groove β1.
  9. Polishing pad after one of the Claims 1 until 8 , wherein the polishing layer further comprises at least one groove γ having a first end Eγ1 and a second end Eγ2, which is closer to the outer circumference of the polishing surface than the first end Eγ1, and which extends from the first end Eγ1 to the second end Eγ2, wherein the first end Eγ1 of the groove γ is located in a region (2) which is a region of less than 70.0% of the radius of the polishing surface from the center of the polishing surface.
  10. Polishing pad after Claim 9 , wherein the first end Eα1 of the groove α is located closer to the outer circumference of the polishing surface than the second end Eγ2 of the groove γ.
  11. Polishing pad after Claim 10 , wherein a difference between a distance A from the center of the polishing surface to the first end Eα1 of the groove α and a distance B from the center of the polishing surface to the second end Eγ2 of the groove γ [distance A - distance B] is 8.0 to 50.0% based on the radius of the polishing surface.
  12. Polishing pad after one of the Claims 9 until 11 , where the length of the groove α is 5.0 to 100.0% relative to the length of the groove γ.
  13. Polishing pad after one of the Claims 9 until 12 , wherein at least one of the slots α and γ has a linear shape.
  14. Polishing process comprising polishing a material to be polished using the polishing pad according to one of the Claims 1 until 13 , wherein the groove α is arranged under a retaining ring that surrounds the material to be polished.
  15. Method for manufacturing a semiconductor, wherein the method includes a step of polishing a semiconductor material by the polishing method according to Claim 14 exhibits.

Description

Technical field The present invention relates to a polishing pad, a polishing method and a method for producing a semiconductor. State of the art For mirror polishing/high-gloss polishing of a material for substrates of semiconductors, silicon wafers and the like, or of a glass or the like that is a material for hard disks, liquid crystal displays and lenses, and for smoothing unevenness of insulating layers, metal layers and the like in a manufacturing process of semiconductor devices, chemical-mechanical polishing (CMP) has traditionally been used, in which a material to be polished is polished by pressing the material against a polishing pad while a polishing slurry (hereinafter also simply referred to as slurry) is applied drop by drop to a polishing surface of the polishing pad. For example, a polishing pad for CMP has grooves such as a spiral groove, concentric grooves, a grid-shaped groove or radial grooves, designed to allow the polishing surface to retain the slurry evenly, remove polishing chips and protect the material being polished from damage due to adsorption. For example, PTL 1 discloses a polishing pad having a polishing layer with a circular polishing surface, wherein the polishing surface has a central region in a range of 0 to 10% of the radius from the center of the polishing surface and a peripheral region in a range of 90 to 100% of the radius from the center of the polishing surface, wherein the polishing layer has at least one helical groove or concentric grooves with several concentrically arranged annular grooves, the helical groove or concentric grooves being arranged from the central region to the peripheral region, and furthermore has radial grooves with at least two segment grooves, each extending from the central region to the peripheral region, wherein the center of the helical groove, the center of the concentric grooves and the center of the radial grooves are located in the central region, wherein the segment grooves have an average length of 30 to 65% of the radius of the polishing surface and a first end in a region with a distance of 5 to 10% and a second end in a region with a distance of 35 to 70% of the radius of the polishing surface from the center of the radial groove, wherein a cross-sectional area Sa ( mm² ) is the average of cross-sectional areas in a direction perpendicular to the longitudinal direction of the segment grooves, and a cross-sectional area Sb ( mm² ) is the average of cross-sectional areas in a direction perpendicular to the tangential direction of the helical groove or the concentric groove, satisfy the condition 0.1 ≤ Sb/Sa < 1.0. Furthermore, for example, PTL 2 discloses a polishing pad with a polishing layer, wherein the polishing layer has at least two concentric grooves, the innermost concentric groove being defined as a first concentric circle and the outermost concentric groove being defined as a second concentric circle, wherein, if the distance from the center of the polishing layer to the innermost position of the first concentric circle is taken as W1, the distance from the outermost position of the second concentric circle to the edge of the polishing layer is taken as W3, and the radius of the polishing layer is taken as R, a first polishing area is the inner area of the first concentric circle, a second polishing area is the area with a distance W2 = R-W1-W3 between the first concentric circle and the second concentric circle, a third polishing area is an area with a distance W3 between the second concentric circle and the edge of the polishing layer, and wherein the third polishing area further comprises a third groove, the outer end of the third groove being connected to the edge of the polishing layer and the inner end of the third groove being within the second is arranged in the polishing area. Furthermore, PTL 3 discloses a polishing pad for CMP with multiple grooves on one surface thereof and with concentric pad circles (circular grooves) whose axis is the axis of rotation of a rotating pad, wherein the plurality of grooves extend substantially perpendicular to a first pad circle and the deviation of the radial component of the multiple grooves becomes substantially greater than the circumferential deviation when the multiple grooves extend from the center of the pad towards the outside of the pad. List of citations Patent literature PTL 1: WO 2023/013576PTL 2: CN 112809550 APTL 3: WO 2006/093670 Summary of the invention Technical problem In CMP, a polishing pad that achieves a higher polishing rate and higher polishing accuracy is desirable. However, according to investigations by the present inventors, it has been difficult to achieve both a high polishing rate and high polishing uniformity in an area near the edge (hereinafter also referred to as the "edge area") of a material to be polished. The present invention has been developed taking into account the aforementioned problem of the prior art, and it is an object of t