Apparatus and a method for high numerical aperture microscopic examination of materials
US5220403A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1992 |
| Grant date | Jun 15, 1993 |
| Priority date | — |
| Expiry date | Sep 30, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/1087
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus and a method for performing high resolution optical imaging in the near infrared of internal features of semiconductor wafers uses an optical device made from a material having a high index of refraction and held in very close proximity to the wafer. The optical device may either be a prism or a plano-convex lens. The plano-convex lens may be held in contact with the wafer or separated from the wafer via an air bearing or an optical coupling fluid to allow the sample to be navigated beneath the lens. The lens may be used in a number of optical instruments such as a bright field microscope, a Schlieren microscope, a dark field microscope, a Linnik interferometer, a Raman spectroscope and an absorption spectroscope.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.