Printed wiring boards
US4351697A · kind A · utility
25Cited by
8References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 4, 1982 |
| Grant date | Sep 28, 1982 |
| Priority date | — |
| Expiry date | Jan 4, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49165
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A printed circuit board is made from a substrate having a copper clad layer thereon by means of first providing spaced through-holes through the substrate, mechanically scrubbing the surface of the substrate and then sputter etching the surface of the substrate so as to remove at least 50A. thereof from the surface and then vacuum metallizing the through-holes subsequent to sputter etching without breaking the vacuum and then finally forming a circuit pattern on the substrate by usual subtractive techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.