Surface inspection method and surface inspection apparatus
US7245366B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 2004 |
| Grant date | Jul 17, 2007 |
| Priority date | — |
| Expiry date | Aug 13, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/94
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A surface inspection apparatus includes an LD (10 for emitting a laser beam (L0), an irradiation optical system for entering the emitted laser beam (L0) onto an inspection surface (210) of a wafer at predetermined depression angle (α), a scanning device (30) to displace the wafer (200) in order for the laser beam (L0) scans the inspection surface (210) in a spiral, an light intensity detecting device (50) to detect light intensity, and a scattered light detecting optical system (40) for guiding scattered light (L2) emitted from an irradiation area (220) in which the laser beam (L0) is entered. The light intensity detecting device (50) includes a multianode PMT (51) for detecting the light intensity by decomposing the scattered light (L2) into 10 channels (ch) in a one-dimensional direction (Y axis direction).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.