Micro Chemical Vias

Previous methods to produce microvias are based on complex technologies such as laser, plasma or photo imaging. Chemical Via is a new chemical method to make microvias for high density printed multilayer circuits. Microvias are used to interconnect adjacent layers and consist of a small diameter hole (usually 70µm) with a thin metallic deposit covering their cylindrical walls to ensure the local conductivity between the bottom and top layers. Microvias of any shapes and dimensions are made possible at a low production costs. The technology was used by CERN PCB manufacturing workshop for the production of PCboards for HEP needs.

Advantages & Applications


  • Microelectronics
  • PCBs industry


  • Vias of several possible dimensions from microns to centimeters
  • Initial fabrication investment to use method is low
  • Vias of any shape (circle, star, square, etc) can be produced and standardized
  • Process or method compatible with all standard PC assembly lines



  • Etching time (9-18 min)
  • An isotropic Etching technique (Deep reactive ion etching) is used
  • Minimum via diameter (40µm)

Innovative features

  • Easy elimination of elements (e.g. glue) by dissolving using a chemical process.
  • Kapton carving by using a sequence of simple chemical baths.
Patent: WO03055288.
Ready for licensing. Patented technology, WO03055288.