Demonstration of Nonvolatile Storage and Synaptic Functions in All-Two-Dimensional Floating-Gate Transistors Based on MoS2 Channels

With the advent of post-Moore era, the development ofmemory devicesbased on bulk materials gradually entered the bottleneck period. Two-dimensional(2D) materials have received much attention due to their excellentoptoelectronic and mechanical properties. Also, floating-gate devicesbased on 2D van der Waals heterostructures have drawn widespread attentionin virtue of their great potential for nonvolatile memory. In thispaper, a floating-gate device based on a MoS2/BN/grapheneheterostructure was fabricated and its electrical storage performanceand synaptic function were investigated. Finally, the device obtainsa switching ratio of close to & SIM;10(5), a large storagewindow of 107.8 V under a sweeping range of & PLUSMN;60 V, good enduranceafter 1000 cycles, and charge retention capability above 1500 s. Inaddition, the device can be used as an artificial synapse to simulatea basic synaptic function and achieve a more linear and symmetricallong-term potentiation and long-term depression profiles. At the sametime, the constructed convolutional neural network using this devicereaches a high recognition accuracy of 95.5% for handwritten numeralsafter 1000 times training. These results demonstrate the great potentialof 2D material floating-gate devices for nonvolatile memory and neuromorphiccomputing, which pave the way for the development of next-generationmemory devices.