Method and apparatus for in-situ monitoring of thickness using a multi-wavelength spectrometer during chemical-mechanical polishing
US6111634A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1997 |
| Grant date | Aug 29, 2000 |
| Priority date | — |
| Expiry date | May 28, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for in-situ monitoring of thickness using a multi-wavelength spectrometer during chemical mechanical polishing (CMP) of a substrate using a polishing tool and a film thickness monitor. The tool has an opening placed in it. The opening contains a monitoring window secured in it to create a monitoring channel. A film thickness monitor views the substrate through the monitoring channel to provide an indication of the thickness of a film carried by the substrate. This information can be used to determine the end point of the CMP process, determine removal rate at any given circumference of a substrate, determine average removal rate across a substrate surface, determine removal rate variation across a substrate surface, and optimize removal rate and uniformity. The film thickness monitor comprises a spectrometer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.