A substantially planar fluid ejection actuator and methods for manufacturing substantially planar fluid ejection actuators for micro-fluid ejection heads. One such fluid ejection actuator includes a conductive layer adjacent to a substrate that is configured to define an anode segment spaced apart from a cathode segment. A thermal barrier segment is disposed between the anode and cathode segments. A substantially planar surface is defined by the anode segment, and the thermal barrier segment. A resistive layer is applied adjacent to the substantially planar surface.