A SHADOW MASK-EVAPORATED TOPSIDE PYROMEMS IGNITER
A shadow mask-evaporated pyroMEMS igniter is presented. The metallization was successfully carried out without ignition or any visible degradation of the propellant charge during evaporation. Directly depositing the Joule-heating igniter onto the propellant charge led to a high level of ignition delay time homogeneity (< 1 ms st. dev.) as well as smooth combustion behavior. Effect of different deposition thicknesses (500 nm vs. 2000 nm), deposition methods (e-beam vs. thermal) and substrate holders (rotary-planetary vs. line-of-sight) on ignition behavior were investigated. Two different ignition regimes were observed depending on input power and igniter thickness: Joule-heating and spark-induced ignition. Highest fabrication repeatability (in terms of electrical resistance) and ignition reliability (in terms of ignition delay time) were obtained with the 2000 nm thick igniters.