A micro-extrusion printhead assembly utilized in a micro-extrusion system to form parallel extruded lines of material on a substrate includes a material feed mechanism for pushing/drawing materials out of dispensing orifices defined in the printhead assembly, a Z-axis positioning mechanism, and a base. A production method utilizes the micro-extrusion system to directly print endpoint structures at the end of each gridline, and by extruding these gridlines immediately after forming the busbars. In accordance with an embodiment of the invention, the micro-extrusion system is controlled to manipulate the printhead speed and/or gridline material extrusion pressure at the beginning, middle and end of each gridline printing process such that teardrop-shaped endpoint structures are formed at the ends of each gridline, whereby each endpoint structure has a substantially greater width than that of the main “central” gridline structure extending between the endpoint structures.