Electric-field induced structural transition in vertical MoTe 2 - and Mo 1– x W x Te 2 -based resistive memories

Transition metal dichalcogenides have attracted attention as potential building blocks for various electronic applications due to their atomically thin nature and polymorphism. Here, we report an electric-field-induced structural transition from a 2H semiconducting to a distorted transient structure (2H d ) and orthorhombic T d conducting phase in vertical 2H-MoTe 2 - and Mo 1− x W x Te 2 -based resistive random access memory (RRAM) devices. RRAM programming voltages are tunable by the transition metal dichalcogenide thickness and show a distinctive trend of requiring lower electric fields for Mo 1− x W x Te 2 alloys versus MoTe 2 compounds. Devices showed reproducible resistive switching within 10 ns between a high resistive state and a low resistive state. Moreover, using an Al 2 O 3 /MoTe 2 stack, On/off current ratios of 10 6 with programming currents lower than 1 μA were achieved in a selectorless RRAM architecture. The sum of these findings demonstrates that controlled electrical state switching in two-dimensional materials is achievable and highlights the potential of transition metal dichalcogenides for memory applications.