Package for integrated circuit
US4724280A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1986 |
| Grant date | Feb 9, 1988 |
| Priority date | — |
| Expiry date | Aug 7, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/3421
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
PLCC (Plastic Leaded Chip Carrier) for a LSI having protuberances on the bottom along its lateral side, is provided with interconnectors between leg portions of adjacent protuberances. Each interconnector is a swelling from the bottom surface of the main body of PLCC to fill the gap, i.e. a channel, between the protuberances. The height of the filling, namely the height of the interconnector, is lower than that of prior art protuberance to leave some space. This space, a channel, serves as a duct for solvent to flow therein smoothly to and from the narrow gap between the soldered lead and the top of the protuberance and is located adjoining this narrow gap. Therefore, the undesirably remaining flux in this narrow gap is perfectly removed by this smooth flow of the solvent. The leg portion of the protuberance is strengthened by the interconnector so that the occurrence of a crack of the protuberance when the moled PLCC is ejected from the molding cavities is considerably reduced. The structure, using the interconnector, can also avoid using a slanted protuberance having a sharp top which is likely to hurt the fingers of a PLCC handler, or which has too narrow a bottom as a channel f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.