Comparison between Pt/TiO_2/Pt and Pt/TaO_X/TaO_Y/Pt based bipolar resistive switching devices

Nonvolatile memories have emerged in recent years and have become a leading candidate towards replacing dynamic and static random-access memory devices.In this article,the performances of T1O_2 and TaO_2nonvolatile memristive devices were compared and the factors that make TaO_2 memristive devices better than T1O_2 memristive devices were studied.TaO_2 memristive devices have shown better endurance performances（10~8times more switching cycles） and faster switching speed（5 times） than TiO_2 memristive devices.Electroforming of TaO_2 memristive devices requires ~ 4.5 times less energy than TiO_2 memristive devices of a similar size.The retention period of TaO_2 memristive devices is expected to exceed 10 years with sufficient experimental evidence.In addition to comparing device performances,this article also explains the differences in physical device structure,switching mechanism,and resistance switching performances of TiO_2 and TaO_2 memristive devices.This article summarizes the reasons that give TaO_2 memristive devices the advantage over TiO_2 memristive devices,in terms of electroformation,switching speed,and endurance.

The effects of substrate temperature on ZnO-based resistive random access memory devices

Ag/ZnO/Zn/Pt structure resistive switching devices are prepared by radio frequency magnetron sputtering. The ZnO thin films are grown at room temperature and 400 ℃ substrate temperature, respectively. By comparing the data, we find that the latter device displayed better stability in the repetitive switching cycle test, and the resistance ratio between a high resistance state and a low resistance state is correspondingly increased. After 104-s storage time measurement, this device exhibits a good retention property. Moreover, the operation voltages are very low： -0.3 V/-0.7 V （OFF state） and 0.3 V （ON state）. A high-voltage forming process in the initial state is not required, and a multistep reset process is demonstrated.

The effects of substrate temperature on ZnO-based resistive random access memory devices

Ag/ZnO/Zn/Pt structure resistive switching devices are prepared by radio frequency magnetron sputtering.The ZnO thin films are grown at room temperature and 400 C substrate temperature,respectively.By comparing the data,we find that the latter device displayed better stability in the repetitive switching cycle test,and the resistance ratio between a high resistance state and a low resistance state is correspondingly increased.After 104-s storage time measurement,this device exhibits a good retention property.Moreover,the operation voltages are very low:-0.3 V/-0.7 V(OFF state) and 0.3 V(ON state).A high-voltage forming process in the initial state is not required,and a multistep reset process is demonstrated.

CMOS-compatible neuromorphic devices for neuromorphic perception and computing: a review

Neuromorphic computing is a brain-inspired computing paradigm that aims to construct efficient,low-power,and adaptive computing systems by emulating the information processing mechanisms of biological neural systems.At the core of neuromorphic computing are neuromorphic devices that mimic the functions and dynamics of neurons and synapses,enabling the hardware implementation of artificial neural networks.Various types of neuromorphic devices have been proposed based on different physical mechanisms such as resistive switching devices and electric-double-layer transistors.These devices have demonstrated a range of neuromorphic functions such as multistate storage,spike-timing-dependent plasticity,dynamic filtering,etc.To achieve high performance neuromorphic computing systems,it is essential to fabricate neuromorphic devices compatible with the complementary metal oxide semiconductor(CMOS)manufacturing process.This improves the device’s reliability and stability and is favorable for achieving neuromorphic chips with higher integration density and low power consumption.This review summarizes CMOS-compatible neuromorphic devices and discusses their emulation of synaptic and neuronal functions as well as their applications in neuromorphic perception and computing.We highlight challenges and opportunities for further development of CMOS-compatible neuromorphic devices and systems.