Temperature-Dependent Electrical Characterization of Multiferroic BiFeO3 Thin Films

The polarization hysteresis and current leakage characteristics of bismuth ferrite, BiFeO 3  (BFO) thin films deposited by pulsed laser deposition was measured while varying the temperature from 80 - 300 K in increments of 10 K, to determine the feasibility of BFO for capacitive applications in memory storage devices. Data is compared to the performance of prototypic ferroelectric barium strontium titanate, Ba x Sr 1-x TiO 3  (BST) under similar conditions. Finding contacts on the BFO samples that exhibited acceptable dielectric properties was challenging; and once identified, the polarization characteristics between them varied greatly. However, the non-uniformity among the contact points within each sample suggests that either the samples were defective (by contamination or growth process), or that the deposition process of the contacts may have undermined the functionality of the devices. Subjected to increasing temperatures, BFO's polarization improved, and though its polarizability was shown to be inferior to BST, the dielectric loss was less.