Process and device for checking the conformity of hybridization balls
US5450206A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1994 |
| Grant date | Sep 12, 1995 |
| Priority date | — |
| Expiry date | May 13, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A process for checking the conformity of hybridization balls present on a chip or a substrate and its implementation device are provided. The process includes positioning the hybridization balls of the electronic component or substrate near a strip transparent to a predetermined wavelength. The hybridization balls are partially flattened against the strip by positioning the electronic component or substrate at a previously defined distance from the transparent strip. The previously defined distance corresponds to a theoretical reference ball height less an acceptable deviation between the theoretical reference ball height and a minimum height of the hybridization balls. The partial flattening creates ball flats on the hybridization balls at the strip. The hybridization balls are illuminated with a light beam of the predetermined wavelength that is emitted through the strip. A portion of the light beam reflected back through the strip by the hybridization balls to be checked and is acquired. Finally, conformity or nonconformity of the hybridization balls to be checked is determined as a function of the portion of said light beam reflected back by each of the hybridization balls.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.