Initiation of nanoporous energetic silicon by optically-triggered, residual stress powered microactuators

The integration of energetic materials with chip-scale MEMS fabrication processes, and in particular the development of nanoporous energetic silicon (NES), is a promising path to provide significant quantities of energy for certain microscale applications. Here we demonstrate the low-power wireless initiation of an on-chip energetic reaction, by absorbing optical energy, transmitting mechanical energy, and releasing a large amount of chemical energy, without the use of any external wires or batteries. A novel actuator powered by residual thin film stress absorbed 25 W/cm2 of optical power from a 532 nm visible laser, heated, and released up to 22 nJ of mechanical energy. The mechanical energy was sufficient to initiate 6.7 mg of NES and release up to 66 J of chemical energy.