Search

Due to their high similarity to biological ion channels, low power consumption, small footprint, and the fact that they do not require reset circuits, threshold switching memristors have been intensively studied for simulating neurons in neuromorphic chips. Switching speed is one of the key challenges which limit the application of threshold switching memristors in chips. In this study, Ta2O5 threshold switching memristors with high switching speeds were prepared by doping with silver. The results show that 14 wt. % Ag doped Ta2O5 threshold switching memristors exhibit excellent bi-directional threshold switching performance, featuring fast switching speeds (<20 ns, <18 ns), low leakage currents (<10 pA), and high switching ratio (>107). According to the field nucleation theory, the rapid switching speed can be attributed to the low nucleation energy (0.26 eV) of silver within the Ta2O5 matrix, which is achieved by incorporating 14 wt. % Ag during the doping process. Based on Pspice, a LIF (leaky integrate-and-fire) neuron based on the silver nanoparticles doped Ta2O5 threshold switching memristors is built, and its firing function has been simulated. The results show that the LIF neuron with a short switching time is able to excite pulse spiking with high frequencies. These results demonstrated that the silver nanoparticles doped Ta2O5-based threshold switching memristors hold significant potential for constructing high-speed artificial neural networks. [ABSTRACT FROM AUTHOR]

This paper investigates the temperature-dependent effects of gamma-ray irradiation on β-Ga2O3 vertical Schottky barrier diodes (SBDs) under a 100 V reverse bias condition at a total dose of 1 Mrad(Si). As the irradiation dose increased, the radiation damage became more severe. The total ionizing dose (TID) degradation behavior and mechanisms were evaluated through DC, capacitance–voltage (C-V), and low-frequency noise (LFN) measurements by varying irradiation, and the test results indicated that TID effects introduced interface defects and altered the carrier concentration within the material. The impact of TID effects was more pronounced at lower temperatures compared to higher temperatures. Additionally, the annealing effect in the high-temperature experimental conditions ameliorated the growth of interface trap defects caused by irradiation. These results suggest that compared to low-temperature testing, the device exhibits higher TID tolerance after high-temperature exposure, providing valuable insights for in-depth radiation reliability studies on subsequent related devices. [ABSTRACT FROM AUTHOR]

The flexible memristor synapses based on binary metal oxides have significant potential in building artificial neural networks to meet people's demands. To obtain flexible memristor synapses with high linearity of conductance update, herein, the effect of Al doping and SiOx layer adding on the flexible TiOx‐based memristor synapse even under bending is studied. The results show that the doping Al and adding SiOx layer improves the linearity of conductance update by 3 times. The bending test results of the SiOx/Al:TiOx‐based memristor synapse show that the linearity decreases slightly with the decrease of the bending radius. When the bending radius is reduced to 5 mm, the total nonlinearity (NL) value of the device is about 0.42. It is still much smaller than the total NL value of TiOx‐based memristor synapse in flat state (about 0.76). The test results of conducting atomic force microscopy show that the improvement of linearity is due to the optimization of conductive filaments. The results provide a feasible program for improving linearity of TiOx‐based flexible memristor synapse even under bending, which can support for the development of high‐performance binary metal oxide flexible memristor synapse. [ABSTRACT FROM AUTHOR]

With the development of the miniaturization of electronic devices, controlling heat dissipation has become a key factor, which affects the service life of devices and energy utilization efficiency. Therefore, it is particularly important to study the heat conduction mechanism of nanomaterials inside microelectronic devices. Herein, the thermal conductivity of MoS2 and graphene/MoS2 heterojunctions using the bond‐order–length–strength theory and the local bond average method is quantitatively analyzed; the functional relationship between the thermal conductivity and the number of layers, temperature, and pressure is established; and the variation trend of thermal conductivity of materials with these factors is studied. The results show that the thermal conductivity of MoS2 and graphene/MoS2 heterojunctions is inversely proportional to the number of layers and temperature, proportional to the pressure. The work provides a simple and effective method for the study of thermal transport properties of 2D materials and heterojunction systems from the perspective of chemical bonding changes at the atomic level. [ABSTRACT FROM AUTHOR]

The performance degradation of a TiO2-film-based RRAM (resistive random access memory) is investigated in a proton irradiation experiment with an energy of 25 MeV. The results reveal that the fabricated Au/TiO2 film/Ti devices exhibit typical I–V of bipolar resistive switching behavior under an irradiation of 1 × 1011 protons/cm2. The low-resistance state (LRS) resistance remains nearly constant, but the high-resistance state (HRS) resistance decreases with an increasing proton fluence. The value of the HRS resistance decreases by approximately one order of magnitude when the value of proton fluence reaches 1 × 1011 protons/cm2. Moreover, the SET voltage decreases with a decreasing proton fluence, while the RESET voltage remains almost constant. Material characterization via x-ray photoelectron spectroscopy demonstrates that the decrease in SET voltage and HRS resistance is mainly caused by radiation-induced oxygen vacancies and non-lattice oxygen. Based on the Voltage Threshold Adaptive Memristor model, a mathematical model of the I–V curve which demonstrates the variation in the RRAM resistance and voltage as a function of proton irradiation is constructed. The simulation results conformed to the experimental results under different proton fluences. Our results form a fundamental guide for the study of radiation performance degradation and radiation hardening of the RRAM with oxygen vacancy conducting filament. [ABSTRACT FROM AUTHOR]