11-bit two-dimensional floating-gate memories

Floating-gate memories (FGMs) show great promise for neuromorphic computing in efficient data-centric applications. However, their limited single-device state capacity remains insufficient for highly integrated precision computing. Here, we demonstrate 11-bit two-dimensional (2D) MoS2 FGMs by contacting the 2D channels with bismuth electrodes, enabling 100 μA on-state current with 108 on/off ratio and reducing the current noise by 3 times (approaching the equipment limits) due to the Schottky barrier-free interfaces. Moreover, we employed a dual-pulse state editing scheme enhancing the stability of our FGMs. The devices show as high as 2,249 distinct conductance levels (>11-bit) while maintaining 230 ns operation speed, >104 s retention, and >105 cycle endurance. Furthermore, the gate-injection operation prevents the influence from generated defects during cycling, maintaining low noise even after 105 cycles and at 85 °C. Theoretical analysis reveals interfacial defects as the primary state-number limitation, suggesting 17-bit capacity is achievable through further trap density reduction. This work establishes 2D FGMs as promising candidates for high-bit-density, low-power neuromorphic hardware. Floating gate memories (FGMs) hold potential for neuromorphic computing, but their single-device state capacity is normally insufficient for precision computing. Here, the authors report the realization of high-performance 11-bit 2D MoS2 FGMs by using Schottky-barrier free Bi contacts and a dual-pulse state editing scheme.