Drying of a nanoparticle solution droplet and development of film fabrication method using ultra-sonic mist

The purpose of present study is to investigate the nanoparticle dispersion formation under drying process of micro solution droplet including nanoparticles, and develop the film fabrication method on the basis of the formation result. First, the Ag nanoparticles dispersed solution is prepared, and the solution droplet is dropped and dried on a glass plate while changing the droplet quantity. Then, the effect of droplet quantity on the Ag nanoparticle dispersion formation is investigated. As a result, it was seen that the nanoparticle dispersion formation depended on presence or absence of internal flow in a droplet under drying process. Second, in-house painting device is developed to produce ~100μm droplets on a glass plate. Using the in-house painting device, the nanoparticle dispersion size can be adjusted by changing blowing time. Next, the nanoparticle solution is fabricated using Al2O3 nanoparticles and water. The concentrations are adjusted to 0.05vol.% with water. The blow and dry of the Al2O3 solusion micro droplets are cyclically conducted on a substrate, then Al2O3 film is formed on a substrate. Consequently, final Al2O3 film structure depends on the blowing time. The valley between Al2O3 particle dispersions decreases with increasing in total blowing time for all blowing times. However, the size of valley becomes large with increasing in blowing time