Ultralow Threshold Voltage Responding Synaptic Memristor Device Based on CuxO and Diamond Schottky Junction.

Herein, an ultralow‐threshold voltage‐responsive synaptic memristor based on Cu<italic>x</italic>O and B‐doped diamond (BDD) heterojunctions is developed. The aggregation of oxygen vacancies corresponding to the high‐ and low‐resistance states forms the foundation for the hysteresis behavior. The <italic>I</italic>–<italic>V</italic> curves exhibit impressive analog resistive switching (analog RS), which renders the memristor highly suitable for simulating synaptic stimulation. The reliable stability of this structure is confirmed using 122 individual devices, achieving a yield of 90.2% with highly consistent <italic>I</italic>–<italic>V</italic> curves. In addition, the effect of the B‐dopant level in the diamond is investigated. By reducing the B/C ratio of the precursor from 1:500 to 1:2000 during the hot filament chemical vapor deposition synthesis process, a significant 55.3% reduction in current is achieved, leading to lower energy consumption. The Schottky barrier height increases with decreasing B‐dopant levels, providing a broader adjustable range for synaptic weight renewal. Remarkably, when the pulse amplitude is decreased to an ultralow value of 3 mV, the synaptic function of the device remains observable, with an energy consumption of only 9.5 × 10−11 J. To the best of the authors’ knowledge, this is the first report of such a low‐amplitude pulse voltage in a two‐terminal memristor. [ABSTRACT FROM AUTHOR]