Physics on development of open-air atmospheric pressure thin film fabrication technique using mist droplets: Control of precursor flow

Abstract

Mist CVD, which is one of the functional thin-film fabrication methods carried out under open-air atmospheric pressure, has been developed for advanced control of precursor streams in order to achieve the fabrication of uniform thin films. In order to obtain a uniform stream of flow including mist droplets, collisional mixing has been considered, and a fine channel (FC) nozzle has been developed using this technology. In the FC, mist droplets are affected by the lift forces toward the direction of the substrate, the gas temperature of the entire area reaches a constant, and owing to the Leidenfrost effect, the evaporation time of a mist droplet is remarkably long as several hundred milliseconds and the migration of a mist droplet extends to a distance of several hundred millimeters. From these characteristic phenomena in the FC, the formation of uniform thin films on the entire surface has been achieved using the FC-type mist (FCM-) CVD system.