CMP polishing pad having edge exclusion region of offset concentric groove pattern

Patent metadata

Field	Value
Publication number	US-9409276-B2
Application number	US-201414515560-A
Country	US
Kind code	B2
Filing date	Oct 16, 2014
Priority date	Oct 18, 2013
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

The invention provides a polishing pad and a method of using the polishing pad for chemically-mechanically polishing a substrate. The polishing pad comprises at least a grooved region and an exclusion region, wherein the exclusion region is adjacent to the circumference of the polishing pad, and wherein the exclusion region is devoid of grooves.

First claim

The invention claimed is:

1. A polishing pad, wherein the polishing pad is characterized by a generally circular cross section, wherein the polishing pad comprises an axis of rotation and a polishing surface, wherein the polishing surface comprises at least a grooved region and an exclusion region, wherein the grooved region comprises a plurality of grooves set into the polishing surface, wherein the plurality of grooves is composed of at least a first plurality of concentric grooves having a first center of concentricity, wherein the axis of rotation of the polishing pad is not coincident with the first center of concentricity, wherein the plurality of grooves is further composed of a second plurality of concentric grooves having a second center of concentricity, wherein the first center of concentricity is not coincident with the second center of concentricity, and wherein the axis of rotation of the polishing pad is not coincident with the first center of concentricity and the second center of concentricity, wherein the exclusion region is devoid of grooves, wherein the exclusion region is adjacent to the circumference of the polishing pad, wherein the exclusion region has an outer boundary and an inner boundary, wherein the outer boundary of the exclusion region is contiguous with the circumference of the polishing pad, and wherein a distance from the circumference of the polishing pad to the inner boundary of the exclusion region is greater than zero.

2. The polishing pad of claim 1 , wherein an average distance from the circumference of the polishing pad to the inner boundary of the exclusion region is denoted by D A , and wherein D A is about 0.1 cm to about 2 cm.

3. The polishing pad of claim 2 , wherein D A is about 1 cm to about 1.5 cm.

4. The polishing pad of claim 3 , wherein D A has a standard deviation of about 0.5 or less.

5. A method of chemical-mechanically polishing a substrate, which method comprises:
(a) contacting a substrate with a chemical-mechanical polishing composition and the polishing pad of claim 1 ,
(b) moving the polishing pad relative to the substrate with the chemical-mechanical polishing composition therebetween, and
(c) abrading at least a portion of the substrate to polish the substrate.

6. The method of claim 5 , wherein a defect count on a surface of the substrate is lower than the defect count on the surface of the substrate when using an otherwise identical polishing pad that does not contain the exclusion region under identical polishing conditions.

7. The method of claim 5 , wherein the substrate comprises copper, and wherein at least some of the copper is removed from the substrate to polish the substrate.

Assignees

• Cabot Microelectronics Corp

Inventors

• Tsai Ching-Ming
• Cheng shi-wei
• Hsu Jia-Cheng
• Yang Kun-Shu
• Chen hui-feng
• Gaudet Gregory
• Liu Sheng-Huan

Classifications

• B24B37/26 Primary

  characterised by the shape of the lapping pad surface, e.g. grooved · CPC title

• H10P52/00

  Grinding, lapping or polishing of wafers, substrates or parts of devices · CPC title

• H10P52/402

  of semiconductor materials · CPC title