Patent · US Expired

Multilayer systems and their method of production

US4657778A · kind A · utility

32Cited by
7References
16Claims
0Family size

Inventor

Key dates

Filing dateJul 18, 1985
Grant dateApr 14, 1987
Priority date
Expiry dateJul 18, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/24926
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of producing a multilayer system comprises depositing a seed layer (4) of copper on an electrically insulating substrate (2). A resist is formed on the copper seed layer (4), and the seed layer is electroplated with copper to produce a desired conductor pattern (8). An air firing dielectric (10) is screen printed over the pattern (8) and the exposed parts of the seed layer (4) are fired in air. The outer skin of the pattern is oxidized as is also the whole of the seed layer other than where it underlies the copper pattern. The ozidized regions of the copper both form a firm bond with the dielectric and inhibit the migration of oxygen into the inner regions of the conductor pattern (8). Also the oxidation of the seed layer renders it non-conductive and therefore obviates the need for its removal. Through holes (12) produced in the dielectric enable electrical connection to the pattern (8).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.