Stripline flex circuit
The invention removes copper from the concave side of a flex circuit around a bendable region and replaces it with a conductive epoxy to allow it to be formed to tighter bend radii than would otherwise be possible. After the flex circuit is shaped in a tight radius and attached to a mechanical structure, the conductive epoxy is cured to act as functional replacement of the removed copper.
1. A method for forming a conformable circuit element, the method comprising:
depositing a conductive layer on a first side of a flex circuit;
etching said conductive layer to form an etched region, wherein the etched region breaks electrical continuity of the conductive layer;
depositing a conductive epoxy on the etched region, wherein the conductive epoxy restores the electrical continuity of the conductive layer;
bending the flex circuit in the etched region to form a concave surface on the first side; and
curing the conductive epoxy.
2. The method of claim 1 , wherein curing the conductive epoxy comprises curing the conductive epoxy until the conductive epoxy becomes structural and conductive.
3. The method of claim 1 , wherein the conductive epoxy is cured into a B-stage state prior to bending the flex circuit.
4. The method of claim 1 , wherein the size of the etched region is determined as a function of a bending radius.