Insulated metal substrates and process for the production thereof
US5230788A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 1992 |
| Grant date | Jul 27, 1993 |
| Priority date | — |
| Expiry date | Jan 31, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/1147
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The disclosure relates to insulated metal substrates and to a process for producing these substrates. These substrates have an aluminium base, an insulant constituted by an alumina film obtained by anodizing at least one of the faces of said base and at least one metal film which is to be transformed by chemical etching into a network of conductors. The alumina film is formed by a uniform compact zone adhering to the aluminium and having a thickness in excess of 500 nm and a porous layer with a rough outer surface. The process of making these substrates includes a step during which at least one of the faces of the aluminium base undergoes a treatment in a porous anodization layer forming bath and then in a barrier anodization layer forming bath. The invention is used in the production of substrates for single face, double face, with metallized holes, and multilayer conductive circuits. The substrates produced have a planar or non-planar configuration, and may also have resistive networks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.