# US 8,465,342 B2 · Method of making and apparatus having windowless polishing pad and protected fiber

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,465,342 B2
- Document ID: US8465342B2
- Status: Granted
- Kind: B2
- Application number: 13/448,299
- Filed: 2012-04-16
- Published: 2012-10-11
- Granted: 2013-06-18
- Earliest claimed: 2009-04-30
- Assignees: Applied Materials, Inc.
- Applicants: Jimin Zhang; Alain Duboust; Doyle E. Bennett
- Inventors: Jimin Zhang; Alain Duboust; Doyle E. Bennett
- Web page: https://patentgrep.com/patent/US8465342B2

## CPC

- B24B 37/205: {provided with a window for inspecting the surface of the work being lapped}
- B24B 37/013: Devices or means for detecting lapping completion
- B24B 49/12: involving optical means
- B24B: MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING (grinding of gear teeth B23F, of screw-threads B23G1/36; by electro-erosion B23H; abrasive or related blasting B24C; tools for grinding, buffing or sharpening B24D; polishing compositions C09G1/00; abrasives C09K3/14; electrolytic etching or polishing C25F3/00; grinding arrangements for use on assembled railway tracks E01B31/17); DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS

## Abstract

A polishing system includes a polishing pad with an aperture that extends through all layers of the polishing pad and a light transmissive film positioned on top of a light-generating or light-guiding element of an optical monitoring system.

## Claims

### Claim 1

An optical monitoring system for a chemical mechanical polishing system, comprising:
a light-source;
a light-guiding element having a first end coupled to the light source and a second end to direct light onto a substrate in the chemical mechanical polishing system; and
a detector positioned to receive reflections of the light directed onto the substrate;
a light-transmissive film positioned on the light-guiding element to protect the light source or light-guiding element from leakage of liquid without contacting a side of an aperture in a platen or polishing pad of the chemical mechanical polishing system.

### Claim 2 (depends on 1)

The optical monitoring system of claim 1, wherein the light-transmissive film is attached to the light-guiding element using a pressure-sensitive adhesive.

### Claim 3 (depends on 1)

The optical monitoring system of claim 1, wherein the light source comprises an incandescent element or a light-emitting diode.

### Claim 4 (depends on 1)

The optical monitoring system of claim 1, wherein the light-guiding element comprises an optical fiber.

### Claim 5 (depends on 4)

The optical monitoring system of claim 4, wherein the optical fiber comprises a bifurcated optical fiber, and the light-transmissive film is secured to a trunk of the bifurcated optical fiber.

### Claim 6 (depends on 5)

The optical monitoring system of claim 5, wherein a first branch of the bifurcated optical fiber has the first end and a second branch of the optical fiber is coupled to the detector.

### Claim 7 (depends on 1)

The optical monitoring system of claim 1, wherein the light-transmissive film is a polymeric material.

### Claim 8 (depends on 7)

The optical monitoring system of claim 7, wherein the light-transmissive film comprises polyethylene terephthalate (“PET”), polychlorotrifluoroethylene (PCTFE), perfluoroalkoxy (PFA), fluorinated ethylene propylene (FEP), or polytetra-fluoro ethylene (PTFE).

### Claim 9 (depends on 1)

The optical monitoring system of claim 1, wherein the light-transmissive film has a refractive index of about 1.48 or less.

### Claim 10 (depends on 1)

The optical monitoring system of claim 1, wherein the light-transmissive film is hydrophilic.

### Claim 11 (depends on 1)

The optical monitoring system of claim 1, wherein the light-transmissive film is hydrophobic.