Method of molding a carrier ring to leads
US5182071A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 1990 |
| Grant date | Jan 26, 1993 |
| Priority date | — |
| Expiry date | Dec 14, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Molding carrier structures to leads of existing semiconductor packages is accomplished by molding at temperatures which maintain approximately matched thermal expansion between an encapsulating material and leads of the semiconductor package. The matched thermal expansion is provided by molding at temperatures below that which is required for glass transition of the encapsulating material. Molding at such temperatures is facilitated by a molding assembly that has a molding pot with an irregular shaped bottom which fluidizes the encapsulating material at low temperatures. Molding at temperatures that essentially match thermal expansion between the package's leads and the encapsulating material prevents damaging the leads of the package.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.