Double-sided hybrid high density circuit board and method of making same
US5072075A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1989 |
| Grant date | Dec 10, 1991 |
| Priority date | — |
| Expiry date | Jun 28, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49155
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A very fine line three-dimensional package is constructed without lamination during construction of the signal core. Construction of the signal core employs a method of line and hole formation and planarization without drilling, and avoids imposing excessive stress on the package during its assembly. In forming the three-dimensional structure, a power core which may comprise a single or multiple layers is manufactured in the conventional method using a very high dielectric constant material. A signal core is on both sides of the power core, using a sequential approach with a low dielectric constant material. The method comprises utilizing photoresist techniques to define the regions of horizontal lines running parallel to the surface of the power core substrate and vertical posts running perpendicular to the surface of the power core, as each layer of lines and posts is established. After metallization of the lines and posts, the dielectric is flowed over the pattern of lines and posts to form a finished layer of the signal core. The sequence is repeated as many times as necessary to build up the required wiring pattern in the signal core. Layers of signal core are built up sequent…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.