Patent ID: 8850792

Claim:
An electrospray thruster comprising: a porous substrate having a plurality of emitters formed on a substantially planar surface thereof and extending perpendicularly thereto, wherein the planar surface of the substrate has a roughness; each of said emitters having at least one groove extending axially along the length of said emitter from the proximal to the distal end thereof; each of said porous substrate and said emitters further having a metalized coating comprising at least a first titanium layer and a further layer of a propellant material disposed thereon; a heater disposed in thermal relation to said porous substrate such that the substrate may be heated substantially uniformly to a temperature sufficient to reduce the viscosity of the propellant such that said propellant flows through and/or across said substrate and upward along said emitter during operation; an extractor electrode grid disposed substantially parallel to said planar substrate, said extractor electrode grid having an aperture aligned above the longitudinal axis of each said emitter such that when a voltage is applied across said extractor grid ions of said propellant are formed and pass through the apertures of said grid to produce thrust; a reservoir for a propellant, the reservoir being formed of a porous material and being in fluid communication with the porous substrate; and wherein dimensions of the pores of said reservoir, the roughness of said substrate and the grooves of said emitters decrease in size from reservoir to substrate to emitter such that the propellant is at least partially drawn from the reservoir through and/or across the substrate and upward along the emitter via a passive capillary action.