Failure mechanisms in thermal inkjet printhead analyzed by experiments and numerical simulation

This paper presents a failure analysis result for enhancing the reliability of thermal inkjet printhead. A novel inkjet printhead is fabricated using MEMS process, and we analyze the failure mechanism of inkjet head based on detailed experimental observations and numerical simulations. The failures presented in this work showed three primary factors influencing the failure modes and lifetime of printhead; bubble cavitation damage, thermal fatigue, and electromigration of heater. The design modification of micro heater to avoid an early stage of failure by electromigration yields the reliability enhancement of thermal inkjet printhead.