Metal-jacketed lead manufacturing process using resist layers
US6248656A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1999 |
| Grant date | Jun 19, 2001 |
| Priority date | — |
| Expiry date | Aug 13, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/486
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Metal leads are formed on a copper conductive layer by applying a first resist and a main resist over the first resist, and forming aligned openings in these resist. A bottom layer of cover metal such as gold is plated onto the copper conductive layer in these openings, followed by a principal metal such as copper. The main resist is then removed so as to expose edges of the principal metal layer. A jacket of cover metal is plated onto the exposed edges and surfaces of the principal metal layer. During this stage, the first resist prevents deposition of the cover metal except on the leads. The jacket merges with the bottom layer of cover material, so as to form a continuous coating extending around the perimeters of the leads. The first resist is removed, and the conductive layer is etched away. The cover metal protects the principal metal during the etching stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.