Structural and electrical characterization of heteroepitaxial Pb[Yb1/2Nb1/2]O3–PbTiO3 thin films

The pulsed laser deposition process has been used to prepare heteroepitaxial (1-x) Pb[Yb1/2Nb1/2]O3–xPbTiO3 (PYbN–PT, x=0.4,0.5) thin films on single crystalline (001)pcSrRuO3/LaAlO3 and (111)pcSrRuO3/SrTiO3 substrates (the subscript pc refers here to the pseudocubic subcell). High laser frequencies (f−16 Hz) and 300 mTorr of background O3/O2 in the chamber during deposition provide stoichiometric and high crystalline quality heterostructures. Temperatures in the 560–660 °C range lead to improved microstructures as well as good dielectric and ferroelectric properties consistent with those of PYbN–PT ceramics. In particular, films show room temperature dielectric constants greater than 1300 and exhibit well-developed hysteresis loops with remanent polarizations (Pr) as high as 40–50 μC cm−2. Results are discussed in terms of film composition and crystallinity.