Descripció del projecte
The aim of this project is to research, develop and optimize the most effective techniques for the micro- and nano-manufacturing of the emitting component of an ‘electrospray’ type motor. Electrospray motors are based on a physical phenomenon by which electrically charged particles can be extracted and accelerated from a conductive liquid through electrostatic fields established between an emitting matrix and an extraction grid; this process is governed by the surface tension of the liquid, its conductivity and the electric field reached in the emitters themselves, under an applied electric potential.
The manufacture of the emitter array is carried out in collaboration with the CNM and the ICN2, taking advantage of new microfabrication techniques. As part of the next necessary steps towards obtaining an optimized version of the engine, the design, manufacture and testing of new emitting matrices is required, which must be able to concentrate the electric field, maximize the thrust density per area, facilitate the supply of propellant to individual emitters and minimize the risk of electrochemical attack.
The doctoral student will be responsible, under the supervision of the company manager and the tutor at ICN2, for the design and manufacture of new electrostatic emitters based on the innovative application of existing micro- and nano-manufacturing techniques. The candidate will carry out a bibliographic review on ‘electrospray’ engines and the physical processes on which they are based; likewise, the revision will be aimed at mapping the various techniques and results of micro-manufacturing for this type of elements, choosing those that are most promising based on the parameters sought to obtain the desired emission regime in the engine. The doctoral student will propose the study of a design space in relation to these parameters, in order to execute its manufacture and subsequent testing, in order to determine the scaling laws of these devices; namely, different emitter packaging configurations, relative distances between them, heights of the microstructures, sharpening, etc. will be executed. The doctoral student will develop the knowledge and skills necessary to be in charge of microfabrication; including the design of lithography masks in AutoCAD or similar, the lithography process for depositing and etching photosensitive resin on silicon wafers or other materials, the dry / wet etching process on the wafer and subsequent nano-texturing processes or surface coating. The geometric characterization of the emitters will be carried out visually by methods of electron microscopy or LASER characterization. Likewise,
