LiNb$_{1-x}$TaxO3 thin films were successfully
deposited on Pt(111)/Ti/SiO2/Si(100) substrates by spin coating
with a diol-based sol-gel technology and rapid thermal annealing.
The effects of various processing parameters, including Ta content
(0$\leq x\leq1$) and heating temperature (500 ~ 800 °C), on
the growth and properties of thin films were investigated. With the
increase of Ta content, the grain size of film decreased slightly,
and the maximum f factor (the degree of c-axis orientation) of
the films were obtained in the composition of x = 0.2. As the
composition of film varied from x = 0 to x = 1, the relative
dielectric constant of film increased from 33 up to 62, and the
dielectric loss factor (tanδ) also increased from 0.00374 to
0.00686, respectively. The coercive field, Ec, and remanent
polarization, Pr, decreased but pyroelectric coefficient, γ,
increased from 2.76 × 10−8 up to 4.51 × 10−8 C/cm2 K. The pyroelectric figures of merit, Fv and Fm,
indicated that film with Ta content of 20 mol% and heating
temperature of 700 °C exhibited the optimized pyroelectric
characteristics and could be applied for high-performance
pyroelectric thin-film detectors.