Hybrid approaches coupling sol–gel and plasma for the deposition of oxide-based nanocomposite thin films: a review

In view of developing new materials with enhanced properties, such as nanocomposite (NC) thin films, special interest has been given in optimizing the deposition processes themselves. The latter, if well selected, could give the freedom to control the NCs synthesis and final properties. Attempting to overcome severe challenges observed when creating NC or oxide-based NC film, hybrid approaches combining injection of colloidal solutions and plasma processes have been proposed. This review focuses on oxide-based NCs, using as an example the TiO2 NPs and SiO2 matrix as NCs, while investigating their optical and dielectric properties. Additionally, this review presents the state-of-the-art in processes for the preparation of the NCs. The major categories of hybrid approaches coupling sol–gel and plasma processes are given. Finally, a comparative study among the published works is provided, aiming in highlighting the impact that each approach has on the physical and chemical characteristics of the produced NCs.