The Influence of Different Nanoscale Channel Lengths in Low-Temperature-Grown Lateral MoS₂ Memristors

The memristor based on low-temperature growth of molybdenum disulfide (MoS₂) is expected to integrate with current IC processes and become one of the fundamental devices for brainlike artificial intelligence hardware. To realize a high-density neural network, it is necessary to identify the size scaling effect of MoS₂ memristors and determine whether they can match the size scaling of transistors. Therefore, the influence of different channel lengths on the performance of lateral nanoscale MoS₂ memristors was investigated in this work. These memristors were constructed by low-temperature metal-organic chemical vapor deposition (MOCVD) growth of two-dimensional (2D) MoS₂ between gold counter electrodes with different nanogaps that define the channel length of these lateral memristors from approximately 14 to 52 nm. By measuring their resistive switching behaviors, we found that the SET voltage decreases with the decrease of the channel length, which was proportional to the power 1.69 of the channel length; the threshold number of pulses (1 V, 1 kHz) required to convert the high-resistance state (HRS) to the low-resistance state (LRS) was found to be proportional to the power 2.87 of the channel length; and the threshold pulse magnitude to output spikes in a leaky integrate-and-fire (LIF) neuron model was found to be proportional to the power 1.01 of the channel length. The results indicate that as the channel length decreases, the voltage, threshold number of stimulation pulses, and threshold pulse amplitude required for resistive switching also decrease at a rate exceeding linear descent, which is basically consistent with the scaling trends of transistors.