Thin Films by EHDA - A Review
A. Jaworek, A. T. Sobczyk, A. Krupa, A. Marchewicz, A. K. Krella, and T. Czech
Institute of Fluid Flow Machinery, Polish Academy of Sciences, Poland
Abstract- ElectroHydroDynamic Atomization (EHDA) is a physical process of liquid dispersion to fine droplets by electrical force and shear stress on the liquid surface. Under these forces, the jet at a capillary nozzle outlet elongates and breaks up into fine droplets at its end. EHDA technique allows production of micron-sized droplets, which can be used for the deposition of thin solid films on substrate. Because the droplets are electrically charged, they disperse uniformly within the space between the nozzle and the substrate that facilitates thin and uniform film deposition. Film morphology can be controlled, to some extent, via controlling charge and size of the droplets, by steering the flow rate of the liquid and voltage applied to the nozzle, and also substrate temperature. Thin solid film can be produced from a solution or colloidal suspension of deposited material after solvent evaporation or from a precursor after chemical reactions occurring at the substrate. By changing the kind of liquid and operational parameters of EHDA system, nanocomposite film can be deposited by a simple way. The paper discusses practical aspects of the applications of EHDA to thin film deposition.
Keywords-ElectroHydroDynamic Atomization, electrospraying, thin film deposition