Insights Into The Low-Temperature Deposition Of A Dense Anatase Tio2 Film Via An Atmospheric Pressure Pulse-Modulated Plasma

A pulse-modulated atmospheric pressure radio frequency (RF) plasma is used to prepare a dense TiO2 thin film at a low temperature. With certain plasma on time (T-on = 50 ms), the discharge temperature decreases with plasma off time (T-off), and the lengths of the thin films increase. An anatase TiO2 thin film was successfully deposited on a temperature-sensitive substrate (polyethylene terephthalate). The transmission electron microscope (TEM) results show that the film is composed from anatase TiO2 nanoparticles grown through plasma in 0.07 s. By using laser light scattering, the TiO2 particles are found to be trapped above the substrate at about 0.27 mm during plasma on, which is close to the simulated plasma sheath thickness (0.26 mm). The deposition mechanism of pulse-modulated atmospheric pressure RF plasma has been investigated.