Low-temperature ZrO2 thin films obtained by polymeric route for electronic applications

A Comparison between Solution-Based Synthesis Methods of ZrO2 Nanomaterials for Energy Storage Applications

“…The cubic form of ZrO 2 is stable at high temperatures (usually above 2370 • C), while the tetragonal is stable within the range of 1170-2370 • C, and the monoclinic phase stabilizes below 1170 • C [4,9]. ZrO 2 exhibits excellent properties, such as good optical transparency in the visible and near-infrared spectral range [13,14], high thermal and chemical stabilities, mechanical strength and fracture toughness, low absorption of light, high index of refraction [15], high corrosion resistance [16], high ionic stability at high temperature, it is biocompatible [17] and presents relatively low leakage current [18] and high breakdown field [19]. Despite this, ZrO 2 presents a wide band gap value (theoretically estimated as ~5.42 eV for monoclinic, ~6.40 eV for tetragonal and ~5.55 eV for cubic phases [14,20,21]).…”

“…ZrO 2 exhibits excellent properties, such as good optical transparency in the visible and near-infrared spectral range [13,14], high thermal and chemical stabilities, mechanical strength and fracture toughness, low absorption of light, high index of refraction [15], high corrosion resistance [16], high ionic stability at high temperature, it is biocompatible [17] and presents relatively low leakage current [18] and high breakdown field [19]. Despite this, ZrO 2 presents a wide band gap value (theoretically estimated as ~5.42 eV for monoclinic, ~6.40 eV for tetragonal and ~5.55 eV for cubic phases [14,20,21]). The introduction of defects in its structure, for instance, through doping with cations or the reduction of particle size below a critical value, is reported to allow the stabilization of high-temperature phases (i.e., cubic and/or tetragonal phases) at RT [22,23].…”

“…In this regard, ZrO 2 has emerged as a potential alternative to replace low-κ SiO 2 in electronic devices [27]. It is reported that the dielectric constant of ZrO 2 films ranges from κ = 20 in the monoclinic phase to κ = 37-47 for the cubic and tetragonal phases, whereas in the case of amorphous ZrO 2 , the dielectric constant values are between 14 and 25 [14].…”

“…ZrO 2 nanomaterials have already been obtained with different morphologies, such as thin films [14], nanoparticles [36], nanobelts [37], nanowires [38] and nanotubes [39], mainly through chemical approaches [40]. The most common methods for the synthesis of ZrO 2 nanostructures include co-precipitation [41], sol-gel [42] and solution combustion [35], sonochemical-assisted methods [43,44], chemical vapor deposition [45], emulsion processing routes [46,47], as well as hydrothermal [10,48] and microwave syntheses [49,50].…”