Low-temperature fabrication and properties of the highly oriented Bi3.15Nd0.85Ti3O12 thin films deposited on different substrates

Bi3.15Nd0.85Ti3O12 (BNdT) films have been prepared on Pt/TiO2/SiO2/Si and (Ba0.5Sr0.5) (Ti,Mn)O3 (BSTMn)/n-Si substrates using a metal organic decomposition method. X-ray patterns show the BNdT films with highly a-axis and (1 1 7) orientation were fabricated by the sequential layer annealing method, which is further confirmed by the shapes of grains in the AFM images. The electrical measurements were conducted on metal–ferroelectric–metal (MFM) and metal–ferroelectric–insulator–semiconductor (MFIS) capacitors. The BNdT film in MFM capacitor exhibits a well-saturated hysteresis loop at an applied voltage of ±10 V, with a remanent polarization of 14.5 μC/cm2 and a coercive field of 81.5 kV/cm. The BSTMn buffer layer is calculated to be about 30 nm by comparing the capacitance-voltage curves with polarization-electric field loops. The ferroelectric and charge injection effects for MFIS are analyzed in detail at various applied voltages. The largest memory window of MFIS is as large as 4.5 V.