Search

CN-122008071-A - Functional structure integrated optimized polishing pad capable of removing uniform materials

CN122008071ACN 122008071 ACN122008071 ACN 122008071ACN-122008071-A

Abstract

The invention discloses a functional structure integrated optimized polishing pad capable of removing uniform materials, which comprises a polishing layer and an elastic layer, wherein the polishing layer is composed of a plurality of bulges, the bulges are arranged in a honeycomb shape, the elastic layer is in a concentric partition structure and comprises a soft area and a hard area, abrasive particle tracks on the surface of a workpiece are uniformly distributed by designing a polishing pad surface pattern, and contact pressure on the surface of the workpiece is uniformly distributed by designing the polishing pad structure. According to the invention, the surface pattern and the structure of the polishing pad are comprehensively optimized, so that the integrated optimization of the polishing pad function and structure is realized, the movement track of abrasive particles and the contact pressure distribution can be cooperatively regulated and controlled, and the material removal uniformity of the surface of a workpiece is improved.

Inventors

  • LI JUN
  • YANG LIANTONG
  • TANG CHAO
  • LU XIAO
  • YU ZHI
  • WANG ZEYU
  • ZHU YONGWEI

Assignees

  • 南京航空航天大学

Dates

Publication Date
20260512
Application Date
20260212

Claims (6)

  1. 1. The polishing pad is characterized by sequentially comprising a polishing layer (1) and an elastic layer (2) from top to bottom, wherein the polishing layer (1) is formed by a plurality of protrusions, the protrusions are distributed in a honeycomb shape, and the elastic layer (2) is of a concentric partition structure and comprises a central soft area (21), an outer ring soft area (23) and a hard area (22) positioned between the central soft area (21) and the outer ring soft area (23).
  2. 2. The polishing pad of claim 1, wherein the protrusions are one or a combination of triangular, square, pentagonal, hexagonal, circular in shape, have a protrusion circumscribing circle diameter of 5-15 mm, and adjacent protrusion gaps of 1-2 mm.
  3. 3. The polishing pad according to claim 1 or 2, wherein the center of the protrusions satisfies the following relationship: Wherein i and j are integers, (x ij , y ij ) are central coordinates of the ith row and the jth column of protrusions, d is the diameter of a protrusion circumscribing circle, w is the clearance between adjacent protrusions, and R is the radius of the polishing pad.
  4. 4. The polishing pad of claim 1, wherein the polishing layer has a thickness of 0.5-3 mm a and the resilient layer has the same thickness as the polishing layer.
  5. 5. The polishing pad according to claim 1, wherein the elastic modulus of the center soft region (21) and the outer soft region (23) is 0.3 to 0.5 times the elastic modulus of the polishing layer, and the elastic modulus of the hard region (22) is the same as the elastic modulus of the polishing layer.
  6. 6. The polishing pad according to claim 1, wherein the width of the hard region (22) is 0.8-0.9 times the diameter of the circumcircle of the workpiece, and the radius of the soft region (21) and the width of the region (23) are each one half of the difference between the radius of the polishing pad and the width of the annular region (22).

Description

Functional structure integrated optimized polishing pad capable of removing uniform materials Technical Field The invention relates to a precise ultra-precise machining technology, in particular to a polishing pad for grinding and polishing, and specifically relates to a functional structure integrated optimized polishing pad capable of removing uniform materials. Background The grinding and polishing technology has become an important means for processing in the fields of integrated circuits, optical elements, semiconductor materials and the like because of the high surface shape accuracy and excellent surface quality. With the increasing diameter of the workpiece, the requirement for planarization is increasing. Among consumables for global planarization, a polishing pad is one of important consumables for determining stability of a manufacturing process. At present, the existing polishing pad has relatively simple surface patterns in the polishing processing process, uneven distribution of abrasive particle motion tracks on the surface of a workpiece, most of structure forms are single-layer or multi-layer composite structures in the vertical direction, the contact pressure on the surface of the workpiece is difficult to realize zonal regulation and control, uneven pressure distribution is easy to generate edge effect, and uneven material removal is caused. Chinese patent CN101327577B discloses a fixed abrasive polishing pad with self-finishing function and good wear uniformity, which can ensure surface shape accuracy for a long time in polishing process by arranging three annular areas with different densities on the polishing layer, thereby improving surface shape accuracy of the workpiece. Chinese patent CN114770372B discloses a polishing pad with a composite surface pattern having a uniform material removal function, which combines a macroscopic effect with a microscopic effect by designing the arrangement of protruding blocks on the surface of the polishing pad and the distribution density of small patterns composited on the surface of the protruding blocks, thereby improving the uniformity of workpiece material removal. Chinese patent CN114193319B discloses a polishing pad with a buffer layer, which selects a proper buffer layer formulation by establishing a time-dependent relationship between the ratio of restoring force and applied pressure in a stress relaxation stage, so that the polishing pad has stable compression restoring characteristics, and can reduce the impact applied to the polishing pad during polishing, thereby improving the uniformity of the whole workpiece. The polishing pad design is based on single factor expansion of surface patterns or structures, has limited regulation and control capability on material removal uniformity, is difficult to realize uniform distribution of abrasive particle motion tracks and contact pressure on the surface of a workpiece, leads to limited material removal uniformity, and cannot meet the high-efficiency and high-quality polishing requirements of the workpiece. Disclosure of Invention In order to solve the technical problems, the invention aims to provide the functional structure integrated optimized polishing pad capable of removing uniform materials, and the functional structure integrated optimization of the polishing pad is realized by comprehensively optimizing the surface pattern and the structure of the polishing pad to realize the uniform distribution of the motion track and the contact pressure of abrasive particles on the surface of a workpiece, so that the functional structure integrated optimization of the polishing pad is realized while the structural conditions such as supporting and yielding are considered while the requirement of uniform material removal function is met. The technical scheme of the invention is as follows: The polishing pad comprises a polishing layer 1 and an elastic layer 2 from top to bottom, wherein the polishing layer 1 is formed by a plurality of bulges which are arranged in a honeycomb shape, and the elastic layer 2 is in a concentric partition structure and comprises soft areas 21 and 23 and a hard area 22. Further, the shape of the protrusions is one or a combination of a plurality of triangle, square, pentagon, hexagon and circle, the diameter of the circumcircle of the protrusions is 5-15 mm, and the gap between adjacent protrusions is 1-2 mm. Further, the protrusion center satisfies the following relationship: Wherein i and j are integers, (x ij, yij) are central coordinates of the ith row and the jth column of protrusions, d is the diameter of a protrusion circumscribing circle, w is the clearance between adjacent protrusions, and R is the radius of the polishing pad. Further, the thickness of the polishing layer is 0.5-3 mm, and the thickness of the elastic layer is the same as that of the polishing layer. Further, the elastic modulus of the soft areas 21, 23 is 0.3-0.5 times of the elastic modulus of