Method for producing multilayer printed wiring boards
US5258094A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 1992 |
| Grant date | Nov 2, 1993 |
| Priority date | — |
| Expiry date | Sep 9, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49165
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A multilayered board is formed by applying a photosensitive insulating resin layer on a laminated plate on which via holes and a circuit pattern are formed, followed by the formation of photoviaholes through the photoprinting method, plating and etching. Then, the multilayered board is adhered to another multilayered board prepared in the same manner through a prepreg layer and a conductive paste while applying heat and pressure to give a multilayer printed wiring board. According to this method, electrical connections between the conductive layer of the upper-most layer and the inner conductive layers, between the inner conductive layers, and between the lower-most conductive layer and the inner conductive layers can be achieved through the photoviaholes and the conductive paste. Therefore, it is not necessary to form through-holes for the electrical connection therebetween. The multilayer printed wiring boards can be substantially improved in the number of layers and wiring density thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.