Automated endpoint detection system during chemical-mechanical polishing
US5985679A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 12, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Jun 12, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N1/32
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An automated endpoint detection process includes obtaining a baseline graph of reflected radiation signal versus time of radiation exposure for a standard integrated circuit substrate surface that is substantially free of residual metal, directing radiation generated from a radiation source through a radiation transparent region of a polishing pad such that radiation is incident on at least a portion of a surface of the integrated circuit substrate, detecting a reflected radiation signal from the integrated circuit substrate surface through the radiation transparent region of the polishing pad, comparing an area under a graph of the reflected radiation signal versus time of radiation exposure obtained for the integrated circuit surface to the baseline graph of the standard integrated circuit substrate surface and thereby determining whether residual metal is present on the surface of the integrated circuit substrate and signaling the chemical-mechanical polishing assembly to stop polishing after polishing for a predetermined time, if the area under the graph of the reflected radiation signal versus time of radiation exposure obtained for the integrated circuit surface is substantia…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.