System for contactless testing of multi-layer ceramics
US4415851A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 1981 |
| Grant date | Nov 15, 1983 |
| Priority date | — |
| Expiry date | May 26, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/305
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system of testing the continuity of electrical conductors extending through an insulating layer without contact. A flood gun irradiates one side of the body to charge the exposed conductors to a given potential. A steerable electron beam scans the front side to generate secondary electron emission from those conductors. The secondary emission is enhanced from conductors with conductivity between front side and back side as a result of the surface potential established by the rear flood beam. The secondary emission varies depending on the state of continuity in the three dimensional network of conductors and produces signals at the detector which allow clear discrimination between uninterrupted and interrupted conductors. The system is applicable for unfired ceramics where contact destroys the specimen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.