A monolithic thermal inkjet printhead utilizing electrochemical etching and two-step electroplating techniques

An integrated fabrication method for a monolithic thermal inkjet printhead is proposed. It utilizes silicon micromachining techniques, such as electrochemical etching to form the main ink feedthrough and two-step nickel electroplating to form the ink cavities and nozzles. The main ink feedthrough is formed by etching the substrate from the back side and the etched hole is automatically aligned with the pattern defined on the front side. The cavity and nozzles are formed sequentially on the silicon substrate by a two-step electroplating. The monolithic batch process provides accurate control in the dimensions of the nozzle and the main ink feedthrough. The fabricated inkjet printhead shows the droplet size of 100 /spl mu/m in diameter and stable ejection of ink droplets of more than 180 million.