There is herein described a method for forming a circuit board comprising: (a) obtaining a substrate of a first formable polymer material, the substrate having at least one electrical conductor on a surface; (b) laminating a coverlay of a second formable polymer material to the substrate to form a flexible circuit board wherein the at least one electrical conductor is disposed between the coverlay and the substrate, the coverlay having a plurality of holes exposing at least a portion of the at least one electrical conductor; (c) electrically connecting light emitting diodes (LEDs) to exposed portions of the at least one electrical conductor; (d) heating the circuit board while applying a force to cause the circuit board to bend and adopt a shape having arcuate cross section; (e) cooling the circuit board until the shape becomes fixed whereby a thermoformed circuit board having an arcuate cross section is formed.