Non-contact method and apparatus for measurement of leakage current of p-n junctions in IC product wafers
US7414409B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Aug 19, 2005 |
| Grant date | Aug 19, 2008 |
| Priority date | — |
| Expiry date | Jul 11, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/311
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A non-contact apparatus and method for measuring of the leakage current and capacitance of p-n junctions in test structures within scribe lanes of IC product wafers is disclosed. The apparatus has a light source optically coupled with a fiber to a transparent electrode at the end of the fiber, which is brought close to the p-n junction under test. The ac signal generated from the test p-n junction is captured by this transparent and conducting coating electrode. The leakage current of a test p-n junction is determined using the frequency dependence of junction photo-voltage signal and reference signals from a p-n junction with low leakage current and known capacitance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.