Electrical Characteristics of Hybrid-Organic Memory Devices Based on Au Nanoparticles

Abstract

We report on the fabrication and characterization of hybrid-organic memory devices based on gold (Au) nanoparticles that utilize metal-insulator-semiconductor structure. Au nanoparticles were produced by sputtering and inertgas condensation inside an ultrahigh-vacuum compatible system. The nanoparticles were self-assembled on a silicon dioxide (SiO 2 )/silicon (Si) substrate, then coated with a poly(methyl methacrylate) (PMMA) insulating layer. Aluminum (Al) electrodes were deposited by thermal evaporation on the Si substrate and the PMMA layer to create a capacitor. The nanoparticles worked as charge storage elements, while the PMMA is the capacitor insulator. The capacitance-voltage (C-V) characteristics of the fabricated devices showed a clockwise hysteresis with a memory window of 3.4 V, indicative of electron injection from the top Al electrode through the PMMA layer into Au nanoparticles. Charge retention was measured at the stress voltage, demonstrating that the devices retain 94% of the charge stored after 3 h of continuous testing.

High capacity organic memory structures based on PVP as the insulating layer

“…Organic memory devices play an important part in plastic and flexible electronic applications [19], which lead to extensive research in this field. Organic memory devices based on charge storage in bistable switching [20][21][22], metal-insulator-semiconductor structures (MIS) [23][24][25][26], and organic thin film memory transistors (OTFMTs) [27][28][29] have been reported in recent years. The main structure to achieve fast and high capacity memory is the floating gate-based memory devices; where a thin film of a floating gate serves as the charge storage element in a transistor or MIS structure [29,30].…”

Single-Walled Carbon-Nanotubes-Based Organic Memory Structures

“…Organic memory devices play a major role in plastic and flexible electronic applications [10], which lead to extensive research in this domain. Organic memory devices, based on charge storage in bistable switching [11,12,13], metal-insulator-semiconductor structures (MIS) [14,15,16,17], and organic thin film memory transistors (OTFMTs) [18,19,20,21] have been reported in the last 20 years. One of the well-known memory structures is the floating gate-based memory device; where typically a thin film of a floating gate serves as a charge storage node in a transistor or MIS structure.…”

“…One of the well-known memory structures is the floating gate-based memory device; where typically a thin film of a floating gate serves as a charge storage node in a transistor or MIS structure. It is reported that stable memory behaviour can be achieved by charging nanoparticles or nanowires, which are integrated into the insulating layer of the MIS structures or thin film transistors [14,19]. When a program voltage is applied between the gate and the source contact, electronic charges can be transferred onto the floating gate by quantum tunneling or thermal emission, charging the floating gate and changing the transistor’s threshold voltage.…”

“…As the dielectric layer isolates the floating gate, charges stored on the floating gate remain there without the need for any applied voltage (nonvolatile memory). To erase the memory, a voltage of opposite polarity should be applied to discharge the floating gate [14].…”

“…On the other hand, there is little or no hysteresis for the control devices of these structures. Furthermore, in our previous work [14,19], we have reported on MIS and transistor structures in which a monolayer of gold nanoparticles was incorporated into insulating films.…”