Semiconductor leadframe and its production method and plastic encapsulated semiconductor device
US5437915A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1994 |
| Grant date | Aug 1, 1995 |
| Priority date | — |
| Expiry date | Jun 16, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24917
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of producing a leadframe for use in semiconductor devices, comprises the steps of forming a space between leads 1a and 1b which are to be overlapped and welded each other, and welding the leads at a region including the space and melting and cutting off one of the leads. In one of the leads which is melted, cohesion and separation of molten metal occur in the region around the space. As a result, unnecessary portions such as an outer frame used for positioning can be cut off at the same time when the leads are connected by welding. Thus, high precision positioning of a plurality of element leadframes as well as high assembling productivity are achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.