A Convergent-Divergent-Convergent nozzle apparatus for direct-whte applications is described. The tip apparatus includes at least three nozzles concentrically positioned in series. In a non-limiting embodiment, a first nozzle has a converging taper, a second nozzle extends from the first nozzle with a diverging taper, and a third nozzle extends from the second nozzle and has a converging taper. The nozzles are positioned in series and are coaxial, and can be formed from either separate components or a monolithic structure. Such an arrangement has permitted direct writing of aerosolized particle streams in line widths from 3.7 - 8 µm in width prior to sintering. Further refinements to the apparatus and processing parameters may result in line widths of 1 µm or less. Aerosolized particles may comprise conductor or semiconductor precursors that may be processed into microelectronic conductors or semiconductors, respectively. The particles may also comprise nanostructures or nanoparticles.