Retaining ring for lower wafer defects

Patent metadata

Field	Value
Publication number	US-10399202-B2
Application number	US-201615074089-A
Country	US
Kind code	B2
Filing date	Mar 18, 2016
Priority date	Mar 19, 2015
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

A retaining ring and a chemical mechanical planarization system (CMP) are disclosed. In one embodiment, a retaining ring for a polishing system includes a ring-shaped body having a polished inner diameter. The body has a bottom surface having grooves formed therein, an outer diameter wall, and an inner diameter wall, wherein the inner diameter wall is polished to a roughness average (Ra) of less than about 30 microinches (μin).

First claim

What is claimed is:

1. A retaining ring for a polishing system, the retaining ring comprising:
a ring-shaped body having:
an upper portion comprising:
a bottom surface having a tab extending therefrom;
an upper inner diameter wall having an inside diameter suitable to accommodate a semiconductor substrate therein, wherein the upper inner diameter wall is polished to a upper wall roughness average (Ra) of about 4 microinches (μin);
a polished upper outer diameter wall;

a lower portion concentric with the upper portion, the lower portion comprising:
a bottom surface having grooves formed therein,
a lower outer diameter wall wherein the polished upper outer diameter wall has a diameter greater than a diameter of the lower outer diameter wall; and
a lower inner diameter wall having a diameter selected to accommodate a semiconductor substrate, wherein the lower inner diameter wall is polished to a lower wall roughness average (Ra) of about 2 microinches (μin) wherein the upper wall roughness average is greater than the lower wall roughness average.

2. The retaining ring of claim 1 , wherein the upper portion is comprised of a metal and the lower portion is comprised of a plastic.

3. The retaining ring of claim 1 , wherein the inner diameter wall is configured to receive a semiconductor substrate having a diameter of 200 mm, 300 mm or 450 mm.

4. The retaining ring of claim 1 , wherein the outer diameter is polished to a roughness averaged of less than about 30 μin.

5. A CMP system comprising:
a rotatable platen configured to support a polishing pad;
a polishing head configured to urge a substrate against the polishing pad during polishing; and
a retaining ring comprising:
an upper portion comprising:
a bottom surface having a tab extending therefrom;
an upper inner diameter wall having an inside diameter suitable to accommodate a semiconductor substrate therein, wherein the upper inner diameter wall is polished to a upper wall roughness average (Ra) of about 4 microinches (μin);
a polished upper outer diameter wall;

a lower portion concentric with the upper portion, the lower portion comprising:
a bottom surface having grooves formed therein,
a lower outer diameter wall wherein the polished upper outer diameter wall has a diameter greater than a diameter of the lower outer diameter wall; and
a lower inner diameter wall having a diameter selected to accommodate a semiconductor substrate, wherein the lower inner diameter wall is polished to a lower wall roughness average (Ra) of about 2 microinches (μin) wherein the upper wall roughness average is greater than the lower wall roughness average.

6. The CMP system of claim 5 , wherein the upper portion is comprised of a metal and the lower portion is comprised of a plastic.

7. The CMP system of claim 5 , wherein the inner diameter wall is configured to receive a semiconductor substrate having a diameter of 200 mm, 300 mm or 450 mm.

8. The CMP system of claim 5 , wherein the outer diameter is polished to a roughness averaged of less than about 30 μin.

Assignees

• Applied Materials Inc

Inventors

• Hu Yongqi
• Yavelberg Simon
• Sheelavant Gangadhar
• Narendrnath Kadthala R

Classifications

• B24B37/32 Primary

  Retaining rings · CPC title