Method of removing flash from a semiconductor leadframe using coated leadframe and solvent
US5070041A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 1989 |
| Grant date | Dec 3, 1991 |
| Priority date | — |
| Expiry date | Aug 10, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49121
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In accordance with the present invention, semiconductor devices are produced by the process involving the steps of obtaining a core-box resin molded item integrated with a lead frame by coating said lead frame on its portions expected to be in non-contact with said core-box resin molded item with an organic high molecular substance having a melting or softening point higher than the molding temperature of the resin constituting said core-box resin molded item and soluble in a solvent which does not dissolve said core-box resin molded item, placing the thus coated lead frame in position within a mold and injecting the resin into the mold thereby carrying out injection or transfer molding and immersing the lead frame bearing core-box resin molded item obtained in the foregoing step in said solvent to remove by dissolving said organic high molecular substance. On that account, flashes of the resin formed on the lead frame can be removed with facility or the formation of said flashes can be suppressed without damaging the resin molded portion, whereby a good electrical connection between the lead frame and the semiconductor element can be accomplished.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.