Fabrication, modeling and testing of a thin film Au/Ti microheater

A thin film gold/titanium (Au/Ti) microheater is developed for microthruster ignition, micro explosive boiling, and micro sensor applications. The microheater was fabricated onto a Pyrex bulk substrate using a micro-fabrication technology. A finite-element based electro-thermal modeling was employed to predict the microheater performance. The variations of the microheater temperature with time, space, and power supply are determined from the modeling. A method is presented to determine the thin film Au/Ti electrical resistivity and thermal conductivity. It was found that significant differences exist between heat transfer in microheater and conventional heater. Experimental testing of the microheater temperature was performed using a customized circuitry. The finite-element model is validated by the experimental measurements.