Structural and dielectric properties of artificial PbZrO3/PbTiO3 superlattices grown by pulsed laser deposition

PbZrO3 (PZO)/PbTiO3 (PTO) artificial superlattices were fabricated by pulsed laser deposition, and their structural and dielectric properties were investigated. Epitaxial PbTiO3 (PTO) and PbZrO3 (PZO) layers were alternately deposited on La0.5Sr0.5CoO3 (LSCO) (100)/MgO (100) substrate at 500 °C with various stacking periods from 1 to 100 unit cells. The (100) plane spacing (d100) of the superlattices increased with decreasing the stacking period, and the corresponding dielectric constant was drastically improved. The dielectric constant of the superlattice reached 800 at a stacking period of 1 unit cell/1 unit cell (PZO1/PTO1). With small stacking periods (PZO1/PTO1 and PZO2/PTO2 unit cells), superlattices exhibited the capacitance-voltage hysteresis, i.e., ferroelectric behavior.