Polishing pad and chemical mechanical polishing apparatus

Abstract

A polishing pad and a chemical mechanical polishing apparatus are provided. The polishing pad includes: a central portion, designed with a central recess; and a peripheral portion surrounding the central portion, and designed with at least one peripheral recess. The at least one peripheral recess is disposed along an annulus contour. A lower part of the peripheral recess is greater than an upper part of the peripheral recess in terms of diameter area, and is different from the upper part in shape.

What is claimed is: 
     
         1 . A polishing pad adapted for a chemical mechanical polishing apparatus, and comprising:
 a central portion provided with a central recess; and   a peripheral portion surrounding the central portion with at least one peripheral recess, wherein the at least one peripheral recess is arranged along an annulus contour, and a lower part of the at least one peripheral recess is larger than an upper part of the at least one peripheral recess in diameter area, and different than the upper part of the at least one peripheral recess in shape.   
     
     
         2 . The polishing pad according to  claim 1 , wherein an upper part and a lower part of the central recess are substantially the same in shape and diameter area. 
     
     
         3 . The polishing pad according to  claim 1 , wherein a diameter width of the upper part of the at least one peripheral recess is equal to or smaller than a diameter width of the central recess. 
     
     
         4 . The polishing pad according to  claim 1 , wherein the at least one peripheral recess comprises a plurality of peripheral recesses dispersedly arranged along the annulus contour, and an upper part of each of the peripheral recesses is a straight hole, and a lower part of each of the peripheral recesses is a U-shaped hole with one end connected to the straight hole. 
     
     
         5 . The polishing pad according to  claim 4 , wherein a top part of each of the peripheral recesses formed by a combination of the straight hole and the U-shaped hole is tilted from a vertical direction toward a central axis of the polishing pad, and the central recess extends into the polishing pad along the vertical direction. 
     
     
         6 . The polishing pad according to  claim 1 , wherein the at least one peripheral recess comprises an annulus peripheral recess, an upper part of the annulus peripheral recess is a straight recess extending continuously along the annulus contour, and a lower part of the annulus peripheral recess is a U-shaped recess that continuously extends along the annulus contour and is connected to the straight recess at one end. 
     
     
         7 . The polishing pad according to  claim 6 , wherein a top part of the annulus peripheral recess formed by a combination of the straight recess and the U-shaped recess is tilted from a vertical direction toward a central axis of the polishing pad, and the central recess extends into the polishing pad along the vertical direction. 
     
     
         8 . The polishing pad according to  claim 1 , wherein the at least one peripheral recess comprises an annulus peripheral recess, an upper part of the annulus peripheral recess is a double annulus recess extending continuously along the annulus contour, and a lower part of the annulus peripheral recess comprises a plurality of holes spaced apart along the annulus contour, and the plurality of holes overlap and are connected to the double annulus recesses respectively. 
     
     
         9 . The polishing pad according to  claim 1 , wherein the at least one peripheral recess comprises an annulus peripheral recess, an upper part of the annulus peripheral recess is a double annulus recess extending continuously along the annulus contour, a lower part of the annulus peripheral recess is an annulus recess that extends continuously along the annulus contour, and the annulus recesses overlap and are connected to the double annulus recess. 
     
     
         10 . A chemical mechanical polishing apparatus, comprising:
 a carrier;   a polishing pad placed on the carrier and comprising a central portion and a peripheral portion surrounding the central portion, wherein the central portion is provided with a central recess, the peripheral portion is provided with at least one peripheral recess, and the at least one peripheral recess is arranged along an annulus contour, a lower part of the at least one peripheral recess is larger than an upper part of the at least one peripheral recess in diameter area and capacity, and is different from the upper part of the at least one peripheral recess in shape;   a wafer suction chuck configured to attach and control a wafer so that the wafer contacts the polishing pad from above; and   a polishing liquid supply device configured to provide a polishing liquid to a surface of the polishing pad from above.   
     
     
         11 . The chemical mechanical polishing apparatus according to  claim 10 , further comprising:
 a polishing pad conditioning device, which contacts the polishing pad from above, configured to remove a polishing residue, and condition a surface of the polishing pad through a rotating disc.   
     
     
         12 . The chemical mechanical polishing apparatus according to  claim 10 , wherein the upper part of the at least one peripheral recess is removed and the lower part thereof is exposed at a later stage of a service life of the polishing pad. 
     
     
         13 . The chemical mechanical polishing apparatus according to  claim 10 , wherein a recess opening area of the peripheral portion of the polishing pad at a later stage of the service life is greater than a recess opening area of the peripheral portion of the polishing pad at an early stage of the service life. 
     
     
         14 . The chemical mechanical polishing apparatus according to  claim 10 , wherein the central portion of the polishing pad maintains substantially a same diameter area in an early stage and a later stage of the service life of the polishing pad. 
     
     
         15 . The chemical mechanical polishing apparatus according to  claim 10 , wherein an upper part and a lower part of the central recess are substantially the same in shape and diameter area. 
     
     
         16 . The chemical mechanical polishing apparatus according to  claim 10 , wherein a diameter width of an upper part of the at least one peripheral recess is equal to or smaller than a diameter width of the central recess. 
     
     
         17 . The chemical mechanical polishing apparatus according to  claim 10 , wherein the at least one peripheral recess comprises a plurality of peripheral recesses dispersedly arranged along the annulus contour, and an upper part of each of the peripheral recesses is a straight hole, and a lower part of each of the peripheral recesses is a U-shaped hole with one end connected to the straight hole. 
     
     
         18 . The chemical mechanical polishing apparatus according to  claim 17 , wherein a top part of each of the peripheral recesses formed by a combination of the straight hole and the U-shaped hole is tilted from a vertical direction toward a central axis of the polishing pad, and the central recess extends into the polishing pad along the vertical direction. 
     
     
         10 . The chemical mechanical polishing apparatus according to claim  10 , wherein the at least one peripheral recess comprises an annulus peripheral recess, an upper part of the annulus peripheral recess is a straight recess extending continuously along the annulus contour, and a lower part of the annulus peripheral recess is a U-shaped recess that continuously extends along the annulus contour and is connected to the straight recess at one end. 
     
     
         19 . The chemical mechanical polishing apparatus according to claim  19 , wherein a top part of the annulus peripheral recess formed by a combination of the straight recess and the U-shaped recess is tilted from a vertical direction toward a central axis of the polishing pad, and the central recess extends into the polishing pad along the vertical direction.