Integrated circuit substrate having through hole markings to indicate defective/non-defective status of same
US6392289B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 15, 1999 |
| Grant date | May 21, 2002 |
| Priority date | — |
| Expiry date | Apr 15, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/1394
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method and apparatus is provided to identify defective laminate objects or package substrates having mounting sites for integrated circuit dies during the package substrate fabrication process. A hole is drilled or punched within the boundary of an individual package substrate contained within a larger laminate substrate and covered with a material layer coating composed of an opaque material such as a resist. The coating may then be selectively applied or removed at a later point during the fabrication process dependent upon whether the package substrate has been classified as defective or non-defective. After specific package substrates have been marked as defective, a light source and light collector are supplied to the fabrication process on opposite sides of the wafer. By shining the light source on the laminate substrate, defective package substrates can be identified by the passage of light through the hole which is no longer covered with resist. A package substrate may have one or many holes corresponding to one or many die mounting sites. Therefore, defective package substrates may be identified through the use of a simple light source and light collector and without the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.