Particle dynamics in deposition of porous films with a modulated radio-frequency atmospheric pressure glow discharge

Nanoparticles grown in a plasma are used to visualize the process of film deposition in a modulated radio-frequency atmospheric pressure glow discharge. Modulation of the plasma makes it possible to successfully prepare porous TiO2 films. We study the trapping of the particles in the sheath during the plasma-on phase. During the plasma-off phase, the particles are driven to the substrate by the electric field generated by their residual charges, leading to the formation of a porous TiO2 film. Using video microscopy, the collective dynamics of particles in the whole process is revealed at the most fundamental “kinetic” level.