Method and apparatus for monitoring a metal layer during chemical mechanical polishing
US6924641B1 · kind B1 · utility
46Cited by
23References
28Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 19, 2000 |
| Grant date | Aug 2, 2005 |
| Priority date | — |
| Expiry date | May 19, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/105
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A sensor for monitoring a conductive film in a substrate during chemical mechanical polishing generates an alternating magnetic field that impinges a substrate and induces eddy currents. The sensor can have a core, a first coil wound around a first portion of the core and a second coil wound around a second portion of the core. The sensor can be positioned on a side of the polishing surface opposite the substrate. The sensor can detect a phase difference between a drive signal and a measured signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.