Enhancement of piezoelectric properties of lithium niobate thin films by different annealing parameters

Abstract

Piezoelectric materials with useful properties find a wide range of applications including opto- and acousto- electronics. Lithium niobate in the form of a thin film is one of those promising materials and has a potential to improve ferroelectric random access memories devices, optical waveguides or acoustic delay lines by virtue of its physical characteristics, e.g. electro-optic coefficient, acoustic velocity, refractive indices etc. The key challenge to overcome is lithium nonstoichiometry as it leads to the appearance of parasite phases and thus aggravates physical and structural properties of a film. According to literature data, in order to obtain microcrystalline piezoelectric phase in previously amorphous films a set of methods is used. In our case we tried to synthesize LN films using congruent target and non-heated silicon substrate and then attain the piezoelectric phase by different annealing parameters. Afterwards LN films were compared to the ones synthesized on the silicon substrate with an additional buffer layer of platinum. Samples were studied by scanning probe microscope. Self-polarization vectors were defined. Based on domain structure images, the histograms of distribution of piezoresponse signals were built.

Multifunctional and Sensitivity Enhancement of Hybrid Acoustoplasmonic Sensors Fabricated on 36XY-LiTaO3 with Gold Nanoparticles for the Detection of Permittivity, Conductivity, and the Refractive Index

“…Note that the SH-SAW sensor sensitivity is affected not only by AuNPs but also by the annealing temperature, − quenching, and the propagation structure of the SH-SAW sensor. − Similar to the SH-SAW sensor sensitivity, the LSPR sensor sensitivity is also affected by the size, distance, and structure of the nanoparticle and its interaction with the medium. − In addition, the simulation of AuNPs with different radii is shown in Figure S4­(a) for the air medium and Figure S4­(b) for the EtOH liquid, Figure S4­(c) shows the σ abs values, and Figure S4­(d) shows the sensitivity effect. Simulation of the dimer AuNPs with different distances is shown in Figure S4­(e) for air and Figure S4­(f) for the EtOH liquid, Figure S4­(g) shows the σ abs values, and Figure S4­(h) shows the sensitivity effect.…”

Sol–Gel Ceramics for SEIRAS and SERS Substrates

“…Zirconia, titania, hydroxyapatite, and lithium niobate have also been obtained with the sol-gel method via the use of alkoxides (Table 1). Examples such as a zirconia membrane for the separation of hydrogen from a mixture of gases [32], zirconia-silver oxide nanoparticles for antibacterial applications [33], titania-polymer thin film composites for catalytic activity [34], titania thin films doped with zinc and nitrogen with bactericidal and photocatalytic activities [35], hydroxyapatite powder doped with silver nanoparticles with antimicrobial activity [36], bioactive poly-ε-caprolactone with alumina and hydroxyapatite composite fibers [37], lithium niobate thin films with optical properties [38], lithium niobate thin films with piezoelectric properties [39], and copper oxide-lithium niobate composites with photocatalytic activity for environmental purposes prepared through the Pechini method [40]. Examples of alumina prepared using alkoxides include the synthesis of γ-alumina using aluminum sec-butoxide [41], γ-alumina microspheres [42], alumina thin films on steel for corrosion protection using aluminum isopropoxide [43], and the use of aluminum triethoxide to improve the properties of a graphene oxide nanocomposite [44].…”

Molten Chlorides as the Precursors to Modify the Ionic Composition and Properties of LiNbO3 Single Crystal and Fine Powders

“…The possibility of fabrication of optical waveguides from LiNbO 3 doped with transition metals was noted in [ 19 , 20 , 21 ]. It is promising to use the LiNbO 3 and PbNb 2 O 6 piezoelectric properties to create novel ultrasonic devices for medical diagnostics [ 22 , 23 , 24 , 25 , 26 , 27 , 28 ].…”