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

Abstract

We report the preparation of (111) preferentially oriented CoFe2O4 thin films on Pt(111)/TiO2/SiO2/Si substrates using a spin-coating process. The post-annealing conditions and film thickness were varied for cobalt ferrite (CFO) thin films, and Pt/CFO/Pt structures were prepared to investigate the resistance switching behaviors. Our results showed that resistance switching without a forming process is preferred to obtain less fluctuation in the set voltage, which can be regulated directly from the preparation conditions of the CFO thin films. Therefore, instead of thicker film, CFO thin films deposited by two times spin-coating with a thickness about 100 nm gave stable resistance switching with the most stable set voltage. Since the forming process and the large variation in set voltage have been considered as serious obstacles for the practical application of resistance switching for non-volatile memory devices, our results could provide meaningful insights in improving the performance of ferrite material-based resistance switching memory devices.

Valence Change Bipolar Resistive Switching Accompanied With Magnetization Switching in CoFe2O4 Thin Film

“…Herein, we present a multifunctional Resistive Switching memory device using CFO thin film with aluminum (a chemically active metal) as top electrode and having a simple structure (Al/CoFe 2 O 4 /FTO(fluorine doped tin oxide)), whose magnetic properties can also be modulated along with the switching in the resistance states only by voltage stimulus. The SET and RESET processes occur in a more uniform and stable manner with a narrow switching voltage distribution at comparatively smaller electric fields compared to previous reports 26 , 27 . The underlying switching mechanism is discussed on the basis of electric/magnetic properties of the device in different states (high resistance state and low resistance state).…”

“…Bipolar Resistive Switching memory devices are considered to be better than Unipolar Resistive Switching devices in terms of data retention, device consistency, controllability and storage performance 25 . Most of the reports on RS properties of stoichiometric magnetic oxides have used noble (chemically inert) material as an electrode, which generally leads to a unipolar behaviour of the device 24 , 26 – 28 . However, using a chemically active material as an electrode can lead to bipolar type of RS and can enhance the performance of the RS device.…”

Artificial Synaptic Performance with Learning Behavior for Memristor Fabricated with Stacked Solution-Processed Switching Layers

“…For now, some researchers have put their effort into investigating the performance improvement of RRAM devices and one of the most significant techniques of the performance improvement was to choose the MO RS layer with stacked-structure thin films. ,− Most of these thin films were fabricated with conventional methods like ALD and sputtering. Yoon et al proposed the RRAM device with the Ta 2 O 5 /HfO 2 stack.…”

Sol–gel synthesis and characterization of single-phase CoLaxFe2−xO4ferrite nanoparticles dispersed in a SiO2matrix

“…[1][2][3][4][5] Among the spinel ferrites, CoFe 2 O 4 has been regarded as one of the competitive candidates for high density magnetic recording media because of its moderate saturation magnetization, high coercivity, mechanical hardness and chemical stability. [6][7][8][9] Magnetic properties of ferrites can be suitably tailored by varying the composition of the cations. [10][11][12][13] Due to rare earth elements (RE) presenting large ionic radii, their substitution into the spinel structure may determine a change in cell symmetry and thus generate internal stress.…”