Nonvolatile electrical bistability of organic/metal-nanocluster/organic system

Abstract

Two-terminal electrical bistable devices have been fabricated using a sandwich structure of organic/ metal/organic as the active medium, sandwiched between two external electrodes. The nonvolatile electrical bistability of these devices can be controlled using a positive and a negative electrical bias alternatively. A forward bias may switch the device to a high-conductance state, while a reverse bias is required to restore it to a low-conductance state. In this letter, a model to explain this electrical bistability is proposed. It is found that the bistability is very sensitive to the nanostructure of the middle metal layer. For obtaining the devices with well-controlled bistability, the middle metal layer is incorporated with metal nanoclusters separated by thin oxide layers. These nanoclusters behave as the charge storage elements, which enable the nonvolatile electrical bistability when biased to a sufficiently high voltage. This mechanism is supported by the experimental data obtained from UV-visible absorption spectra, atomic force microscopy, and impedance spectroscopy.

Electrical memory devices based on inorganic/organic nanocomposites

“…9 Semiconducting materials, for example, MoO 3 and so on, 10 with suitable energy band levels can also be used in place of the metal particles. However, as shown by the vast differences in the electrical characteristics of the devices fabricated in different laboratories, 3,[6][7][8] the reproducibility of the device depends very much on the vacuum chamber and deposition conditions. Therefore, a more repeatable fabrication process is required for the large-scale manufacture of such devices.…”

“…The metal layer has been shown not to form a continuous film when the deposition rate and the thickness are low (Figure 1). [6][7][8] For the case of aluminum, aluminum oxide may be formed spontaneously because of residual oxygen in the vacuum chamber. 6 This insulating oxide layer is believed to be important as it can improve the charge retention properties of the nanoparticles.…”

“…After the transition is finished, the ON state remains in the device even after the power is turned off, which reveals the nonvolatile nature of the hybrid memory device. 6 Depending on the I-V characteristics, three types of nonvolatile memory effects, write-once-read-many-times and unipolar and bipolar electrical switching, can be observed for hybrid devices. The writeonce-read-many-time memory exhibits an irreversible electrical transition upon external voltage stimulation.…”

Dynamic Behavior of Resistive Random Access Memories (RRAMS) Based on Plastic Semiconductor

“…One emerging candidate is the resistance random access memory (RRAM) based on metal oxides [2,3] and organic semiconductors [4][5][6]. These RRAMs have shown electrically induced resistive switching effects and have been proposed as the basis for future non-volatile memories.…”

New Electronic Memory Device Concepts Based on Metal Oxide-Polymer Nanostructures Planer Diodes

“…In the previous paper it has shown that the resistive switching will occur through the polymer capped nanostructure silver oxide embedded in a planer diode with two gold electrodes [1]. There are lots of reports showing different mechanisms for resistive switching observation [2][3][4][5][6][7][8][9].…”