Resistive switching properties and physical mechanism of cobalt ferrite thin films

Abstract

We report reproducible resistive switching performance and relevant physical mechanism of sandwiched Pt/CoFe2O4/Pt structures in which the CoFe2O4 thin films were fabricated by a chemical solution deposition method. Uniform switching voltages, good endurance, and long retention have been demonstrated in the Pt/CoFe2O4/Pt memory cells. On the basis of the analysis of current-voltage characteristic and its temperature dependence, we suggest that the carriers transport through the conducting filaments in low resistance state with Ohmic conduction behavior, and the Schottky emission and Poole-Frenkel emission dominate the conduction mechanism in high resistance state. From resistance-temperature dependence of resistance states, we believe that the physical origin of the resistive switching refers to the formation and rupture of the oxygen vacancies related filaments. The nanostructured CoFe2O4 thin films can find applications in resistive random access memory.

CoFe2O4 and CoFe2O4‐SiO2 Nanoparticle Thin Films with Perpendicular Magnetic Anisotropy for Magnetic and Magneto‐Optical Applications

“…Cobalt ferrite is an attractive material, because it offers a combination of semiconducting [ 1 ] and magnetic properties including high coercivity, anisotropy, and magnetostriction. [ 2 ] This results in a vast range of applications in magnetoelectrics, [ 3,4 ] magnetic strain sensors, [ 5 ] resistive switching random access memories, [ 6 ] high density magnetic recording media, [ 4,7 ] and microelectromechanical systems. [ 8 ] In addition, it has a high Kerr rotation in the 400-800 nm range, which is accessible by the common lasers used in the optical industry.…”

Properties of Zirconium Oxide and Cobalt Ferrite Layered Nanocomposite

“…Resistive switching behavior has been observed and described, e.g., in CoFe 2 O 4 films electrodeposited on porous alumina templates 34 and chemical solution deposited on planar platinum electrodes. 35 Figure 7 demonstrates capacitance-voltage and admittance (conductance) -voltage loops measured from the same composite sample. The measured magnitudes in there are conductance as the real part of the admittance, and capacitance as the imaginary part of the admittance.…”

Regulation of the forming process and the set voltage distribution of unipolar resistance switching in spin-coated CoFe2O4 thin films

“…When the bias voltage increased, injected carriers started to increase. However, oxygen vacancies or other defects existed in CFO could behave as traps and capture the injected carriers [16,19]. The square law shown for voltages higher than 0.7 V implied that under this condition, the traps in the CFO thin films were almost filled and the I-V characteristics were governed by a trap-free space-charge limited (SCL) conduction [24].…”

“…Sol-gel-derived CFO and sputtering-deposited CFO thin films have been investigated for their RS properties, and the reported results mainly focused on the conduction mechanisms in the HRS and LRS [16,19]. The Pt/CFO/Pt structure has been reported to show URS with high retention capability and no detectable degradation for more than 10 4 s [19]. In this work, we prepared CFO thin films with spincoating and studied the effect of post-annealing conditions and film thickness on the RS properties of Pt/ CFO/Pt structure.…”