Multi-bit memories fabricated through mechanical and plasma induced deformation of layered semiconductors

To realize hardware-based artificial intelligence (AI) systems for practical applications, it is necessary to create new memory devices with multiple (or analog-tunable) long-lasting memory states.[1] In our work, we identify that the interlayer deformation in layered semiconductors can form multiple long-lasting, metastable charge-trapping states, which can be exploited to fabricate memory transistors with multi-bit data storage states. We have demonstrated that both plasma treatment and mechanical shear exfoliation can be used to generate such charge-trapping states, and the fabricated MoS2 and WSe2 memory transistors have 2-bit and 3-bit data storage states with year- and day-scale retention times, respectively. This work advances the scientific and technical knowledge for manipulating charge memory states in layered materials and producing multi-bit memory components.