Circuit board fabrication leading to increased capacity
US4511757A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 13, 1983 |
| Grant date | Apr 16, 1985 |
| Priority date | — |
| Expiry date | Jul 13, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S428/901
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Printed circuit boards having a plurality of circuit layers are produced on a copper-clad substrate by first forming a pattern in a desired configuration to produce the first layer of the printed circuit board, then covering it with an energy-sensitive material comprising a rubber modified epoxy resin, an acrylated epoxy resin and a viscosity modifier; the energy-sensitive material is delineated in a desired pattern and developed to uncover portions of the underlying metallization pattern and the entire substrate is then blanket cured to produce a rigid layer having openings in appropriate places; the openings are metallized and a second copper pattern is produced on the cured polymer by conventional metallization and lithographic techniques. If desired, the process is repeated until a suitable number of copper patterned levels are obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.