Process for producing ink jet printhead

The present invention relates to a process for producing an ink jet printhead so as to enhance printing quality. The process comprises steps of providing a substrate, forming a patterned layer on the substrate, forming a dry photoresist layer with a flow-guiding channels and a plurality of nozzles on the patterned layer, and finally bonding a nozzle plate onto the dry photoresist layer. The patterned layer include a base patterned layer and an auxiliary patterned layer. The auxiliary patterned layer and base patterned layer are cooperated to form a central portion as the flow-guiding channel. The base patterned layer includes a heating layer and a passivation layer. The auxiliary patterned layer and the base patterned are made of identical materials and have substantial height.