US 4,543,715 A · Method of forming vertical traces on printed circuit board

Abstract

A multilayer printed circuit board (10) is provided with vertical circuit traces (51-54) which are readily accessible by mechanical means, by first creating vias at the locations of the vertical circuit traces (51-54). An opening (59) is then bored in a manner that the perimeter of the opening (59) intercepts the vias. The remaining plating material on the vias forms the vertical circuit traces (51-54), which are thereby established along the perimeter of the opening (59). This technique utilizes procedures which are readily adaptable to present multilayer printed circuit board manufacturing techniques and which effect a low cost and reliable connection. Furthermore, the vertical circuit traces (51-54) are readily accessible for mechanical broaching and can be formed in a relatively high-density configuration.

Claims14

Dependent claims

Method for forming vertical conductive traces on a multilayer printed circuit board having at least one internal layer characterized by:

forming a plurality of via holes;
and
establishing conductive plating paths along the via holes;
boring an opening along said pattern having walls substantially parallel to the via holes, thereby leaving the vertical traces,
wherein the step of establishing conductive plating paths along the via holes includes electroless plating of the via holes prior to boring the opening.

2 more elements

Dependencies are inferred from the claim text.

Method of forming vertical traces on printed circuit board

Life of this patent

Method of forming vertical traces on printed circuit board

Life of this patent

Abstract

Claims14