Robust non-volatile bipolar resistive switching in sol-gel derived BiFeO3 thin films

Abstract

BiFeO 3 thin films are deposited on FTO coated glass substrates using a simple sol-gel deposition technique, limiting thickness about 70 nm and Ag/BiFeO 3 /FTO RRAM devices are prepared. The devices showed low-voltage bipolar switching with the maximum I on /I off ~ 450, and low set and reset voltages ~ 1.1 V and -1.5 V, respectively. The devices are stable against on-off cycles with ~ 10 4 s retention time without any significant degradation. The variations in the set and reset voltages are 0.4 V and 0.6 V, respectively. We found that ohmic and trap-controlled space charge limited conductions are responsible for low and high resistance states, respectively. The resistive switching mechanism is attributed to the formation and rupturing of the metal filament during the oxidation and reduction of Ag ions for the set and reset states. Introduction:The resistive random access memory (RRAM) based non-volatile memory devices are attracting attention due to their simple device geometry, high switching speed, low power consumption, longer retention time and switching endurance in conjunction with the possibilities for scaling up towards practical applications. 1-3 This works on the principle of resistive switching, which can be realized in simple metal-insulator-metal (MIM) capacitorlike structures. The RRAM device switches between conducting and non-conducting states by manipulating external stimuli, such as electric field. 4-6 These devices are explored in numerous transition metal oxides and perovskites like HfO 2 7 , TiO 2 8 , Al 2 O 3 9 , Ta 2 O 5 10 ,

Excellent Bipolar Resistive Switching Characteristics of Bi4Ti3O12 Thin Films Prepared via Sol-Gel Process

“…With a rise in voltage corresponding to the increase in injected carriers, oxygen vacancies are filled with electrons, and the current passing through the film increases. At the time when defects composed of oxygen vacancies brim with injected electrons, the current will noticeably increase, representing a switch from the HRS to LRS [51]. In addition, both the positive and negative voltage regions of the conduction mechanism of the LRS were governed by Ohm's law, indicating the conductive filaments formed in the BIT films [52].…”

Electrode Dependence of Local Electrical Properties of Chemical-Solution-Deposition-Derived BiFeO3 Thin Films

“…On the other hand, RS or conductivity property investigations on chemical-solution-deposition (CSD) , -derived epitaxial BFO thin films are not that abundant. , Recently, we have shown it possible to synthesize high-quality epitaxial BFO films via CSD with robust ferroelectric properties on lanthanum strontium manganite (La 0.67 Sr 0 . 33 MnO 3 , LSMO)/buffered (001) strontium titanite (SrTiO 3 , STO) substrates (where the LSMO layer was grown by pulsed-laser deposition, PLD).…”

Power‐Efficient and Highly Uniform BiFeO3‐Based Memristors Optimized with TiInSnO Electrode Interfacial Effect

“…This indicates the TiInSnO memristor exhibits greatly improved uniformity with stable bipolar resistance switching properties. Moreover, compared with the ever‐reported BFO‐based memristors, [ 11–13 ] the present BFO memristor with TiInSnO electrode exhibits significantly improved consistency.…”

“…[9,10] Nevertheless, most of BFO-based devices with conductive filaments (CFs) formation and rupture have unstable switching processes, correspondingly leading to large cycle-to-cycle variations in resistive switching. [11][12][13][14] High-performance memristors to meet the requirements of highly uniform, large storage windows, and low-power consumption are yet to be developed.Diminution for power consumption, enhancement of uniformity, and expansion of storage window in a definitive and effective way are urgent need and critical challenges, which are also very important for low-power storage and neuromorphic computing applications. Currently, to improve the performance of the memristors, much of work are devoted to changing the novel structures, investigating resistive switching layer and electrode material.…”