Configurable Resistive Response in BaTiO₃ Ferroelectric Memristors via Electron Beam Radiation

Abstract

Ferroelectric oxide memristors are currently in the highlights of a thriving area of research aiming at the development of nonvolatile, adaptive memories for applications in neuromorphic computing. However, to date a precise control of synapse‐like functionalities by adjusting the interplay between ferroelectric polarization and resistive switching processes is still an ongoing challenge. Here, it is shown that by means of controlled electron beam radiation, a prototypical ferroelectric film of BaTiO3 can be turned into a memristor with multiple configurable resistance states. Ex situ and in situ analyses of current/voltage characteristics upon electron beam exposure confirm the quasi‐continuous variation of BaTiO3 resistance up to two orders of magnitude under the typical experimental conditions employed in electron beam patterning and characterization techniques. These results demonstrate an unprecedented effective route to locally and scalably engineering multilevel ferroelectric memristors via application of moderate electron beam radiation.

Bifunctional Device with High‐Energy Storage Density and Ultralow Current Analog Resistive Switching

“…[ 12–15 ] Therefore, the two devices have been individually treated because of the competing relationship between polarization and resistive switching processes since the change of free charge determines the resistance state of the former while the latter is dominated by the polarization charge. [ 16 ] Recently, a capacitive‐coupled memristive effect has been suggested to illustrate the nonpinched current–voltage ( I – V ) hysteresis loop based on a model of parallel connecting an ideal memristor and capacitor. [ 17 ] It also implies the feasible coexistence of the functions of the memristor and solid supercapacitor in principle.…”

Interface Modification in Three‐Terminal Organic Memory and Synaptic Device

“…Two-terminal memory devices include common memristor, resistive random-access memory (RRAM), and so on. [127,128,134,135] Compared with two-terminal memory devices, three-terminal memory devices based on transistor [29,136,137] can implement the operation of reading and programming simultaneously, offering many potential applications. [138] Usually, the gate electrode is analogous to the pre-synaptic neuron, and the channel between source and drain electrodes is analogous to post-synaptic neuron.…”

Site‐Specific Regulated Memristors via Electron‐Beam‐Induced Functionalization of HfO2

“…[1] In fact, with a two-terminal electrode/active layer/electrode configuration, the resistance of the RS device-also referred to as memristors-depends on the history of the applied electrical bias, offering the capacity to store information in the form of electrical resistance. [9][10][11][12][13] Particularly, as an active layer, metal oxide acts as an oxygen reservoir, in which electric-field-induced movement of oxygen vacancies (or equivalently oxygen anions) can be confined and/or uniform, which leads to generating localized and/ or homogeneous RS, respectively. [12][13][14][15] In fact, nanoscale conducting channel (one or more) is formed in a localized RS device, that causes conducting channel where the device resistance changes from high to low levels, like the "0" and "1" bits in a digital storage system.…”

“…[9][10][11][12][13] Particularly, as an active layer, metal oxide acts as an oxygen reservoir, in which electric-field-induced movement of oxygen vacancies (or equivalently oxygen anions) can be confined and/or uniform, which leads to generating localized and/ or homogeneous RS, respectively. [12][13][14][15] In fact, nanoscale conducting channel (one or more) is formed in a localized RS device, that causes conducting channel where the device resistance changes from high to low levels, like the "0" and "1" bits in a digital storage system. [1,3,16] However, several issues, including inherent variation in switching voltages, access to multilevel data storage, unpredicted temporal/spatial control of filament formation, and wildly fluctuating conductance, make it challenging to use localized RS devices for controlled memory storage and meet the demands of brain-inspired computing.…”

“…Indeed, the switching behavior in both (localized or homogeneous) is likely to appear by the reversible creation and annihilation of conductive channels via a redox reaction triggered by electric field-induced oxygen vacancy movement. [4,13] Thus, the capacity to alter the quantity of composition flaws of an active medium, such as, the concentration of oxygen vacancies, could be a potential approach for adjusting the redox processes and associated oxygen-ion dynamics, which in turn can offer a wide modulation of resistive degrees of freedom in oxides. However, to the best of our knowledge, so far, the main difficulty in the technical implementation of RS devices has remained the effective manipulation of the oxygen vacancies externally, which uniquely could alter the controlled formation and stabilization of the conduction channel.Note that it is widely recognized that fundamental behaviors of materials (like structural, charge transport, optoelectronics, Emerging nonvolatile resistive switching, also known as the memristor, works with a distinct concept that relies mainly on the change in the composition of the active materials, rather than to store the charge.…”