Apparatus for making surface photovoltage measurements of a semiconductor
US5091691A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 1988 |
| Grant date | Feb 25, 1992 |
| Priority date | — |
| Expiry date | Dec 7, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/2656
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for making ac surface photovoltage (SPV) measurements of a specimen of semiconductor material under dc bias voltage conditions includes a light source whose output beam is intensity modulated, an adjustable dc bias voltage source, a conductive base for supporting the specimen and a novel capacitance type reference electrode assembly for sensing the SPV signals. The reference electrode assembly includes in one embodiment a button made of insulating elastomeric material and attached to a rigid plate made of insulating material. A film made of insulating material and having a conductive coating on one side which serves as a reference electrode is attached to the button. When SPV measurements are being taken, the film is pressed against the specimen with pressure sufficient to hold the reference electrode in close compliance with the specimen, with pressure being applied to the plate from an external source and being transmitted from the rigid plate to the film through the elastomeric button.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.