Production of lead frame
US5221428A · kind A · utility
39Cited by
1References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 6, 1991 |
| Grant date | Jun 22, 1993 |
| Priority date | — |
| Expiry date | Sep 6, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49121
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for producing a lead frame which comprises selectively forming a photoresist film on both sides of a lead frame material of three-layered structure, with an etching stop layer interposed between two metal layers, etching both sides thereof using the photoresist film as a mask, and removing the unnecessary part of the etching stop layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.