Laser imaging of printed circuit patterns without using phototools
US5895581A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 24, 1997 |
| Grant date | Apr 20, 1999 |
| Priority date | — |
| Expiry date | Jun 24, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24917
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method of manufacturing a conducting pattern on a non-conducting substrate, that leads to a printed circuit board (PCB). The method obviates the use of phototools and is known in the art as "direct write" (DW). It is achieved by coating the copper cladding of an insulating laminate with one or more very thin (1 to 10 micron) metallic layer or layers, that can act as copper etch-resists, when top-coated with at least one laser-imageable polymeric layer, where the principal function of the laser-defined polymeric coating is to achieve high resolution imaging, leaving the major "burden" of copper etch resistance to the metallic coating(s) that are exposed, bared following the laser imaging operation. The substantial advantage of this invention is that the etch resistance is principally achieved by the metal-bearing layer or layers underneath the organic areas that are left on the copper cladding following laser patterning. As a result, the PCBs prepared according to the present invention can use extremely thin layer(s) of laser-imageable organic coatings, and thereby achieve fast scanning speeds or low laser energies, since the organic/polymeric imag…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.