Improving linearity by introducing Al in HfO₂ as a memristor synapse device

Abstract

Artificial synapse having good linearity is crucial to achieve an efficient learning process in neuromorphic computing. It is found that the synaptic linearity can be enhanced by engineering the doping region across the switching layer. The nonlinearity of potentiation and depression of the pure device is 36% and 91%, respectively; meanwhile, the nonlinearity after doping can be suppressed to be 22% (potentiation) and 60% (depression). Henceforth, the learning accuracy of the doped device is 91% with only 13 iterations; meanwhile, the pure device is 78%. A detailed conduction mechanism to understand this phenomenon is proposed.

Digital and Analog Switching Characteristics of InGaZnO Memristor Depending on Top Electrode Material for Neuromorphic System

“…6(a) and (b). In general, the symmetric and linear weight-update characteristics of synaptic device with regard to conductance are necessary for an accurate weight-mapping of artificial neural network algorithm [47][48][49][50][51]. However, most of memristive devices generally have asymmetric and nonlinear switching characteristics during potentiation (SET) and depression (RESET) processes.…”

Highly Linear and Symmetric Weight Modification in HfO2‐Based Memristive Devices for High‐Precision Weight Entries

“…Because the RESET process follows the SET process, it is reasonable that the overall operational voltages for SET and RESET are largely determined during the SET process. [32,33] To estimate the electronic energy barrier qualitatively, conductance values (verified at 0.1 V) of LRS and HRS of Types 1 and 2 were measured as a function of where I, A, E a , k B , and T represent the current measured at 0.1 V, numerical coefficient, activation energy, Boltzmann constant, and absolute temperature, respectively. Based on the numerical relationship between the logarithmic current and reciprocal temperature, we extracted the activation energy from the slope of the plot.…”

Multi-Level Analog Resistive Switching Characteristics in Tri-Layer HfO2/Al2O3/HfO2 Based Memristor on ITO Electrode

“…The physical limitation of the conventional flash memory gives rise to the development of resistive random access memory (RRAM) due to its low power consumption, higher density, and simple structure, which consist of mainly transition metal oxides sandwiched between the top and bottom electrodes [ 1 , 2 , 3 , 4 , 5 , 6 ]. Although, single layer RRAM devices have been found to have uncontrolled filament formation and high switching voltage [ 7 , 8 , 9 ].…”