Inkjet printhead construction

摘要

An inkjet printhead constructed by micro-electromechanical systems (MEMS) processing techniques includes a plurality of ink ejection nozzles, each nozzle defining a nozzle chamber. The printhead has a plurality of external thermal bend actuators. Each actuator has a proximal end anchored to a substrate and a distal end connected to an ink ejection paddle within a respective chamber. The external thermal bend actuator further comprises a series of layers and includes a planar conductive heating circuit layer which includes a first portion adjacent said proximal end forming a planar conductive heating circuit for heating said thermal bend actuator, and a second portion extending to said ink ejection paddle. The second portion being electrically isolated from said first portion by means of a discontinuity in said planar conductive heating circuit layer. The discontinuity is located external to said nozzle chamber.