Electronic synapses made of layered two-dimensional materials

Recommended Methods to Study Resistive Switching Devices

“…A projected endurance of 10 years has been reported based on I-t curves collected at 85 °C in Pt/TaO x / Pt [129] and Pt/Al 2 O 3 /HfO 2 /Al 2 O 3 /TiN/Si. [135], the authors measured the relaxation time of Ti/h-BN/Au thresholdtype RS devices during more than 500 cycles, and the variability of the relaxation time observed was strikingly low (<10%, see Figure 6d). Studying the retention time of threshold-type RS devices is interesting in the field of neuromorphic computing, as they are suitable to emulate short-term plasticity learning rules because the retention time of the RS cell can be also interpreted as the relaxation time of an electronic synapse.…”

2D Layered Materials for Memristive and Neuromorphic Applications

“…Similar to the TMOs-based memristive devices, other ions migration, for example, B 3+ , N 3− and O 2− , in 2D layered materials have been proposed to account for the growth and rupture of filaments in vertical memristive devices; [57,60,80,109,112,113,129] It is well known that ions migration in conventional memristive devices causes the formation of filaments, while electricfield-induced S 2− migration in MoS 2 based planar structure memristive devices leads to the movement of grain boundaries and gives rise to resistive switching. Similar to the TMOs-based memristive devices, other ions migration, for example, B 3+ , N 3− and O 2− , in 2D layered materials have been proposed to account for the growth and rupture of filaments in vertical memristive devices; [57,60,80,109,112,113,129] It is well known that ions migration in conventional memristive devices causes the formation of filaments, while electricfield-induced S 2− migration in MoS 2 based planar structure memristive devices leads to the movement of grain boundaries and gives rise to resistive switching.…”

“…[60,86] However, it is different in Ag/WO 3 − x /WSe 2 /Gr vertical devices. In traditional TMOs-based synaptic devices, modulating the shape of LTP/LTD and realizing the transition between STP and LTP usually rely on the variation of the amplitudes and frequency of input voltage pulses.…”

“…The modulation and transition could be realized by applying gate voltages, which dramatically simplifies the control of input signals. 2020, 6,1901107 [60] Copyright 2018, Springer Nature Publishing AG. The vertical resistance of the barristor is gate-tunable as Schottky barrier height changes with the gate voltage.…”

“…[55] Compared to conventional TMOs materials, 2D layer-structured materials show much better mechanical strength. With graphene as transparent electrode, conductive atomic force microscope (CAFM) [60] and Raman spectrum [61] can be used to locate the filaments and their morphology. Although the growth of conductive filaments and electrochemical dynamics of nanoscale clusters in the TMOs-based memristive devices have been studied by transmission electron microscopy, [7,58,59] further understanding of switching mechanism may benefit from the use of transparent 2D materials.…”