The present disclosure provides a method of fabricating an electrode structure. The method provides an electrically insulating substrate having a first surface, a second surface opposite the first surface, and a plurality of through-holes, each through-hole extending across a thickness of the insulating substrate. The method further comprises extruding a material sequentially or simultaneously through at least some of the through-holes resulting in a plurality of elongate electrically conductive elements extending through and protruding from the through-holes at the first surface of the electrically insulating substrate. In addition, the method comprises forming a plurality of electrically conductive regions at the second surface of the electrically insulating substrate. Each electrically conductive region is located at a respective through-hole, whereby the electrically conductive regions are electrically coupled to the elongate electrically conductive elements.
