Patent · US Expired

Via hole structure and process for formation thereof

US5308929A · kind A · utility

20Cited by
7References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 27, 1992
Grant dateMay 3, 1994
Priority date
Expiry dateJul 27, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05K2201/09845
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A via hole structure for interlayer connection formed in an insulating film and a process for the formation of the same. Via holes are formed in an insulating film of a multilayer interconnected board or the like so as to have a shape such that when a metallic film for wiring is formed on the insulating film, the metal film can completely fill up the via holes. The via holes are formed by gradually increasing from the bottom toward the top of an insulating layer 8 the apertures of the via holes 7 formed in the insulating layer 8, comprised of a plurality of insulating resin film or photosensitive insulating resin film layers 2, 5, in a multilayer interconnected board comprising the insulating layer 8 laminated alternately with a wiring layer 13 comprised of an electric conductor.

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