Surface inspection apparatus using radiation or light
US6693293B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 2001 |
| Grant date | Feb 17, 2004 |
| Priority date | — |
| Expiry date | Feb 21, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/9513
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A surface inspection apparatus is constructed of an illumination unit for irradiating a wafer with illumination radiation for inspection, and a radiation receiving unit having a CCD imaging device for detecting an image of the wafer by converging regularly reflected radiation from the wafer. The wafer surface is inspected based on the image detected by the CCD imaging device. An incident angle i and a wavelength &lgr; of the use-for-inspection illumination radiation with which the illumination unit irradiates the wafer, are set to satisfy the following conditional formula:&lgr;/(sin i+1)≦p  (1)where p is a pattern repetitive pitch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.