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

Abstract

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.

Direct Liquid Reactor-Injector of Nanoparticles: A Safer-by-Design Aerosol Injection for Nanocomposite Thin-Film Deposition Adapted to Various Plasma-Assisted Processes

“…Recently, new attractive methods based on aerosols have been proposed [11,12]. These approaches implement liquid solutions of pre-prepared nanoparticles directly injected into the plasma in the form of liquid droplets.…”

Soft polymerization of hexamethyldisiloxane by coupling pulsed direct‐liquid injections with dielectric barrier discharge

“…For example, nanocomposites were produced using a solution of metal (gold) salts dissolved in a polymerizable solvent (isopropanol) [ 31 ] or colloidal solutions with metal‐oxide (ZnO, TiO 2 ) nanoparticles injected in low‐ and atmospheric‐pressure plasmas. [ 12,32‐36 ]…”

“…For example, nanocomposites were produced using a solution of metal (gold) salts dissolved in a polymerizable solvent (isopropanol) [31] or colloidal solutions with metal-oxide (ZnO, TiO 2 ) nanoparticles injected in lowand atmospheric-pressure plasmas. [12,[32][33][34][35][36] In all studies based on aerosols and plasmas reported in the literature, precursors for thin-film deposition are injected in a continuous way. Depending on the substrate temperature, applied power conditions (continuous or pulsed), reactant partial pressure and flow rate, and location of the substrate along the gas flow lines, the socalled "soft plasma polymerization" (SPP) can be achieved.…”

Time-Resolved Analysis of the Electron Temperature in RF Magnetron Discharges with a Pulsed Gas Injection

“…The properties of such materials can be tailored by the chemical composition, crystal structure, and morphology of the matrix, but also by the nature, size, form, volume fraction, and distance between each nanometric inclusions (particles, filaments, tubes) [21,22]. Many studies are devoted to plasma processes with pulsed gas injection [23]. A new "hybrid" method based on a pulsed injection mode has been recently proposed [24].…”