Bias-dependent interface roughening and its effect on electric bistability of organic devices

Abstract

Atomic force microscopy (AFM), field-emission scanning electron microscopy, and energy dispersive X-Ray spectroscopy are used to study morphological and compositional variations of metal-organic interfaces in organic bistable devices. The results show that bias voltage causes rougher interfaces with new protrusions, and the switching phenomena origins from the evolution of these protrusions under external electric field. In order to exclude other possible factors, three types of bistable devices are designed and examined. In addition, metal-coated AFM probes are utilized to simulate the switching process, which yields similar results and corroborates our conclusion.

Single-Electron Charging Effects in Hybrid Organic/Inorganic Nanomembrane-Based Junctions

“…Here, the applied electric fields are ≥1 MV/cm, superior to those commonly reported for the devices poisoned by metal diffusion. , Additionally, both finger and tube electrodes are relatively rough: root-mean-square/peak-to-valley roughness of 1 nm/3.2 nm and 3 nm/8.5 nm, respectively (Figure S2), which can increase the local electric field by the proximity of electrode point contacts . Rough electrodes can also suffer from an additional bias-induced roughening, which can create sharper or new protrusions in the electrodes . The characteristics of the molecular film (ultrathin ∼5 nm, mechanically soft and pin hole-compliant) make the diffusion of electrode particles into the junction even more probable.…”

“…25 Rough electrodes can also suffer from an additional bias-induced roughening, which can create sharper or new protrusions in the electrodes. 50 The characteristics of the molecular film (ultrathin ∼5 nm, mechanically soft and pin hole-compliant) make the diffusion of electrode particles into the junction even more probable.…”

Electronic transport in semiconducting molecular ensembles

“…[10] Rough electrodes can also suffer from an additional bias-induced roughening, which can create sharper or new protrusions in the electrodes. [168] The characteristics of the SMEultrathin, ~ 5 nm, mechanically softmake the diffusion of electrode clusters into the junction even more probable.…”