Fig. 1: The structure of gradual TiOx memristor and its electrical characteristics.
a Schematic of Pt/gradual TiOx/Ti memristor structure showing gradual oxygen concentration in the TiOx layer. b Consecutive 125 I–V sweep curves of the device showing very small temporal variation (1.39%) during the cycles. c Endurance test showing 5 × 106 consecutive set/reset pulse without degradation. d Spatial variation (3.87%) calculated through DC voltage sweep in the 30 stand-alone devices. e Fifty consecutive cycles of the pulsed response of a single stand-alone device. A single cycle is composed of 200 set pulse responses (4.5 V, 10 µs) and following self-decaying during 200 ms with a 40 ms decaying time constant. f A 2D map for the decay time constant of 400 devices in a 20 × 20 cross-bar array. g Analog conductance change in a 20 × 20 cross-bar array with 0, 4, 8, 12, and 16 set pulses (4.5 V, 100 µs). h A 3D representation of the conductance change along with the set pulses.
