A method of constructing an electrophysiology catheter having a flex circuit electrode assembly includes: providing a flex circuit having a substrate, a first conductive layer and a second conductive layer； removing the first conductive layer to expose a first surface of the substrate； forming the wiring electrode in the second conductive layer with one exclusion zone； forming a first through-hole in the substrate to provide one conductive via and forming a second through-hole to provide an irrigation aperture in alignment with the exclusion zone； forming the contact electrode on first surface of the substrate； placing conductive material into the first through-hole to form the conductive via, the conductive via extending through the substrate and electrically coupling the wiring electrode and the contact electrode； and coupling a first conductor and a second conductor to the wiring electrode to form a thermocouple.
