Window in thin polishing pad

Patent metadata

Field	Value
Publication number	US-11161218-B2
Application number	US-201916252513-A
Country	US
Kind code	B2
Filing date	Jan 18, 2019
Priority date	Feb 26, 2016
Publication date	Nov 2, 2021
Grant date	Nov 2, 2021

Abstract

A polishing pad includes a polishing layer stack that has a polishing surface, a bottom surface, and an aperture from the polishing surface to the bottom surface. The polishing layer stack includes a polishing layer that has the polishing surface. A fluid-impermeable layer spans the aperture and the polishing pad. A first adhesive layer of a first adhesive material is in contact with and secures the bottom surface of the polishing layer to the fluid-impermeable layer. The first adhesive layer spans the aperture and the polishing pad. The light-transmitting body is positioned in the aperture and has a lower surface in contact with, is secured to the first adhesive layer, and is spaced apart from a side-wall of the aperture by a gap. An adhesive sealant of a different second material is disposed in and laterally fills the gap.

First claim

What is claimed is:

1. A polishing pad, comprising:
a polishing layer stack having a polishing surface, a bottom surface, and an aperture from the polishing surface to the bottom surface, the polishing layer stack including a polishing layer having the polishing surface;
a fluid-impermeable layer spanning the aperture and spanning the polishing pad;
a first adhesive layer of a first adhesive material in contact with and securing the bottom surface of the polishing layer stack to the fluid-impermeable layer, the first adhesive layer spanning the aperture and the polishing pad;
a light-transmitting body positioned in the aperture, the light-transmitting body having a lower surface in contact with and secured to the first adhesive layer and spaced apart from a side-wall of the aperture by a gap; and
an adhesive sealant of a different second material disposed in and laterally filling the gap; wherein an air gap separates the adhesive sealant from the first adhesive layer.

2. The polishing pad of claim 1 , wherein the light-transmitting body is softer than the polishing layer.

3. The polishing pad of claim 2 , wherein the polishing layer has a hardness of about 58-65 Shore D and the light-transmitting body has a hardness of about 45-60 Shore D.

4. The polishing pad of claim 1 , wherein the adhesive sealant has about the same hardness as the light-transmitting body.

5. The polishing pad of claim 4 , wherein the light-transmitting body and the adhesive sealant have a hardness of about 45-60 Shore D.

6. The polishing pad of claim 1 , wherein the gap completely laterally surrounds the light-transmitting body.

7. The polishing pad of claim 1 , comprising a second adhesive layer positioned on a side of the fluid-impermeable layer opposite the first adhesive layer and in contact with the fluid-impermeable layer.

8. The polishing pad of claim 7 , comprising a second aperture through the second adhesive layer aligned with the light-transmitting body.

9. The polishing pad of claim 7 , further comprising a removable liner covering the second adhesive layer.

10. The polishing pad of claim 1 , wherein the first adhesive material comprises a pressure sensitive adhesive and the second material comprises a cured epoxy or polyurethane.

11. The polishing pad of claim 1 , wherein the polishing layer stack comprises the polishing layer and a backing layer, and wherein the polishing layer is a napped polyurethane and the backing layer is a different material than the polishing layer.

12. The polishing pad of claim 11 , wherein each of the backing layer and the fluid-impermeable layer are a polyester.

13. The polishing pad of claim 1 , wherein the polishing pad has a total thickness less than about 3 mm.

Assignees

• Applied Materials Inc

Inventors

• Hu Yongqi
• Narendrnath Kadthala Ramaya
• Terry Thomas Lawrence

Classifications

• B24B37/205 Primary

  provided with a window for inspecting the surface of the work being lapped · CPC title

• B24B37/22

  characterised by a multi-layered structure · CPC title

• B24B37/24

  characterised by the composition or properties of the pad materials · CPC title