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 system for pushing/drawing materials out of extrusion nozzles defined in the printhead assembly, a Z-axis positioning mechanism, and a base. The micro-extrusion printhead includes a layered nozzle structure sandwiched between back and front plate structures. The layered nozzle structure includes stacked plates including top and bottom nozzle plates sandwiching a nozzle outlet plate. According to various embodiments, at least one of the nozzle structure materials of the printhead assembly, the output geometry of the printhead assembly, and the internal conduit geometry of the printhead assembly are modified to cause the bead traveling through the extrusion nozzle to be reliably directed (biased) toward the target substrate as it leaves the printhead nozzle orifice.