Method and apparatus for detecting the endpoint of a chemical-mechanical polishing operation using optical techniques

US6809032B1 · kind B1 · utility

Assignee

• Advanced Micro Devices, Inc. · US

Inventors

• Frank Mauersberger · Radebeul, DE
• Peter J. Beckage · Austin, US
• Paul R. Besser · Sunnyvale, US
• Frederick N. Hause · Austin, US
• Errol Todd Ryan · Wappingers Falls, US
• William S. Brennan · Austin, US
• John A. Iacoponi · San Jose, US

Key dates

• Filing date: May 1, 2002
• Grant date: Oct 26, 2004
• Expiry date: Nov 29, 2022

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/76801
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

In another aspect of the present invention, a system for detecting an endpoint in a polishing process is provided. The system comprises a polishing tool, a controllable light source, a sensor, and a controller. The polishing tool is capable of polishing a surface of a semiconductor device, wherein the semiconductor device includes a first layer comprised of a first material and a second layer comprised of a second material. The first layer is positioned above the second layer. The controllable light source is capable of delivering light having one of a plurality of a preselected frequencies to the surface of the semiconductor device. The sensor is capable of detecting the light reflected from the surface of the semiconductor device. The controller is capable of determining the second material, instructing the controllable light source to deliver light of one of the frequencies in response to the second material, comparing the reflected light to a preselected setpoint, and modifying the polishing process in response to the reflected light exceeding the preselected setpoint.