Electrical switching of molecular thin films filled in metal oxide cracks

In this work, we report an approach to fabricate molecular junctions based on metal oxide thin films with nanoscale cracks. The growth of the cracked oxide films is systematically investigated, which reveals that the crack width can be tuned by varying the dopants and/or the heating rate. Current-voltage measurements show that the as-fabricated molecular junction exhibits stable and reproducible electrical switching performance. The ON state junction obeys the Ohmic conduction, while the OFF state follows the space-charge-limited transport. The switching mechanism is shown to be governed by a charge trapping/detrapping process taken place in the organic active layer.