Low-pressure crystallization of sol-gel-derived PbZr0.52Ti0.48O3 thin films at low temperature for low-voltage operation

Abstract

The properties of sol-gel-derived 120-nm PbZr0.52Ti0.48O3 thin films crystallized in low-pressure O-2 ambient at 500degreesC have been investigated. it is found that PbZr0.52Ti0.48O3 films crystallized in low-pressure oxygen ambient exhibit higher remanent polarization as well as a lower coercive field, compared to those annealed in O-2 atmosphere. The remanent polarization (i.e., 2P(r)) for samples annealed in 60 mbar O-2 ambient is as high as 36 muC/cm(2), and the coercive field (2E(C)) is 99.9 kV/cm at an applied voltage of 2 V. The improvement of P-E hysteresis loops by low-pressure oxygen annealing is ascribed to less incorporation of oxygen and other residues in the resultant PbZr0.52Ti0.48O3 films, since the reductions in the amount of these residual species are beneficial for the complete transformation of the perovskite structure. The reductions in oxygen content and amounts of other residues such as CO2 and H2O are confirmed based on Auger depth profiles and thermal desorption spectra (TDS), respectively.