Monolithic Silicon-Based Microthruster for Orbital and Attitude Control Fabricated by Using MEMS Technologies

In the last decades there has been an increasing development of small satellites allowing remarkable reduction of both cost and fabrication time. In parallel, there has been a general increase of LEO missions for Earth observation based on small satellites. The miniaturization technologies developed in the 80’s have allowed the development of microsensors and microactuators compatible with applications on microsatelites. This trend has stimulated the need of microthrusters to maintain orbital and attitude control requiring thrust ranging from some micro-Newton to some milli-Newton. In this work is described the design and development of a Micro Thruster, monolithically fabricated in Silicon with photolithographic technologies usually applied for MEMS fabrication. The thrust is obtained by using, as propellant, high concentration H₂O₂ that is induced to the liquid-to-vapour phase exothermal transition by means of a suitable catalyst. Design parameters, fabrication details as well as preliminary tests will be presented and discussed.