Inspection system and apparatus
US7634365B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2008 |
| Grant date | Dec 15, 2009 |
| Priority date | — |
| Expiry date | Feb 25, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/0095
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and system for identifying a defect or contamination on a surface of a sample. The system operates by detecting changes in work function across a surface via both vCPD and nvCPD. It utilizes a non-vibrating contact potential difference (nvCPD) sensor for imaging work function variations over an entire sample. The data is differential in that it represents changes in the work function (or geometry or surface voltage) across the surface of a sample. A vCPD probe is used to determine absolute CPD data for specific points on the surface of the sample. The combination of vibrating and non-vibrating CPD measurement modes allows the rapid imaging of whole-sample uniformity, and the ability to detect the absolute work function at one or more points.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.