Electro-optic sampling prober
US6388454B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Nov 30, 1999 |
| Grant date | May 14, 2002 |
| Priority date | — |
| Expiry date | Nov 30, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R13/347
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electro-optic sampling prober is used to measure a waveform of a measured signal applied to wiring of an IC wafer. Herein, a laser radiates laser beams, which are supplied to an optical module containing an optical isolator and photodiodes by way of an optical fiber. Then, the laser beams pass through an optical wavelength filter to propagate through a prober unit. The laser beams are incident on an electro-optical element, which is changed in polarization state in response to an electric field being caused by the measured signal. The laser beams are reflected by a surface mirror of the electro-optical element, so that reflected beams propagate back through the prober unit and are returned to the optical module by way of the optical wavelength filter. During the measurement, a human operator watches an image of a selected portion of the IC wafer presently placed beneath the prober unit to adjust a positional relationship between the prober unit and IC wafer. The image is produced by an infrared camera equipped with a halogen lamp and a monitor. Incidentally, the optical wavelength filter has an optical characteristic such that a center wavelength in transmission of light coincid…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.