Dislocations often exhibit unique physical properties distinct from those of the bulk material. However, functional applications of dislocations are challenging due to difficulties in the construction of high-performance devices of dislocations. Here we demonstrate unidirectional single-dislocation Schottky diode arrays in a Fe2O3 thin film on Nb-doped SrTiO3 substrates. Conductivity measurements using conductive atomic force microscopy indicate that a net current will flow through individual dislocation Schottky diodes under forward bias and disappear under reverse bias. Under cyclic bias voltages, the single-dislocation Schottky diodes exhibit a distinct resistive switching behavior containing low-resistance and high-resistance states with a high resistance ratio of ∼103. A combined study of transmission electron microscopy and first-principles calculations reveals that the Fe2O3 dislocations comprise mixed Fe2+ and Fe3+ ions due to O deficiency and exhibit a one-dimensional electrical conductivity. The single-dislocation Schottky diodes may find applications for developing ultrahigh-density electronic and memory devices.
Keywords: Schottky diode; conductive atomic force microscopy; dislocation; first-principles calculations; transmission electron microscopy.