Chemical mechanical polishing pads having offset circumferential grooves for improved removal rate and polishing uniformity

Patent metadata

Field	Value
Publication number	US-2018354094-A1
Application number	US-201715617263-A
Country	US
Kind code	A1
Filing date	Jun 8, 2017
Priority date	Jun 8, 2017
Publication date	Dec 13, 2018
Grant date	—

Abstract

The present invention provides a chemical mechanical (CMP) polishing pad for planarizing at least one of semiconductor, optical and magnetic substrates comprising a polishing layer that has a geometric center, and in the polishing layer a plurality of offset circumferential grooves, such as circular or polygonal grooves, which have a plurality of geometric centers and not a common geometric center. In the polishing layer of the present invention, each circumferential groove is set apart a pitch distance from its nearest or adjacent circumferential groove or grooves; for example, the pitch increases on the half or hemisphere of the polishing layer that is farthest from the geometric center of its innermost circumferential groove and decreases on the half of the polishing layer nearest that geometric center. Preferably, the polishing layer contains an outermost circumferential groove that is complete and continuous.

First claim

We claim:

1 . A chemical mechanical (CMP) polishing pad for planarizing at least one of semiconductor, optical and magnetic substrates comprises a polishing layer that has a geometric center, the polishing layer containing a plurality of offset circumferential grooves which have a plurality of geometric centers and not a common geometric center, each circumferential groove being set apart a pitch distance from its nearest or adjacent circumferential groove or grooves.

2 . The CMP polishing pad as claimed in claim 1 , wherein the polishing layer contains an outermost circumferential groove that is complete and continuous and that is concentric with the polishing layer itself or has a common geometric center with and is not offset from the geometric center of the polishing layer.

3 . The CMP polishing pad as claimed in claim 1 , wherein in the polishing layer having the plurality of offset circumferential grooves, when going from the innermost circumferential groove to the outermost circumferential groove the relative location of the geometric center of each successive offset circumferential groove moves toward the geometric center of the polishing layer; and, the outermost circumferential groove of the polishing layer has a geometric center substantially corresponding with the geometric center of the polishing layer.

4 . The CMP polishing pad as claimed in claim 1 , wherein except for the innermost and the outermost circumferential groove, each of the plurality of offset circumferential grooves has two adjacent circumferential grooves and the geometric centers of the majority of the offset circumferential grooves that have two adjacent circumferential grooves are offset from the geometric centers of their respective two adjacent circumferential grooves.

5 . The CMP polishing pad as claimed in claim 4 , wherein the majority of the offset circumferential grooves that have two adjacent circumferential grooves are offset from their respective two adjacent circumferential grooves by from 25 to 200 μm (1 to 8 mils).

6 . The CMP polishing pad as claimed in claim 1 , wherein the majority of the offset circumferential grooves are offset by from 200 to 35,000 μm from the geometric center of the polishing layer.

7 . The CMP polishing pad as claimed in claim 1 , wherein the majority of the offset circumferential grooves are offset by from 500 to 21,500 μm from the geometric center of the polishing layer.

8 . The CMP polishing pad as claimed in claim 7 , wherein all of the offset circumferential grooves except the outermost circumferential groove are offset by from 500 to 21,500 μm from the geometric center of the polishing layer.

9 . The CMP polishing pad as claimed in claim 1 , wherein each of the circumferential grooves in polishing pad is polygonal, having from 3 to 36 sides, or is substantially circular.

10 . The CMP polishing pad as claimed in claim 1 , wherein the polishing layer comprises a plurality of radial grooves.

Assignees

• Rohm & Haas Elect Materials Cmp Holdings Inc

Inventors

• Qian Bainian
• Brugarolas Brufau Teresa
• Kozhukh Julia

Classifications

• B24B37/26 Primary

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

• B24B37/22

  characterised by a multi-layered structure · CPC title

• B24B37/04

  designed for working plane surfaces · CPC title

• H10P52/00

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

• H10P52/402

  of semiconductor materials · CPC title