Eddy current gain compensation
US8408965B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 2009 |
| Grant date | Apr 2, 2013 |
| Priority date | — |
| Expiry date | Dec 26, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/105
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
In-situ monitoring during processing of a substrate includes processing a conductive film on a substrate in a semiconductor processing apparatus and generating a signal from an eddy current sensor during processing. The signal includes a first portion generated when the eddy current sensor is adjacent the substrate, a second portion generated when the eddy current sensor is adjacent a metal body and not adjacent the substrate, and a third portion generated when the eddy current sensor is adjacent neither the metal body nor the substrate. The second portion of the signal is compared to the third portion of the signal and a gain is determined based at least on a result of the comparing, and the first portion of the signal is multiplied by the gain to generate an adjusted signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.