Improved Memory Properties of Graphene Oxide-Based Organic Memory Transistors

Abstract

To investigate the behaviour of the organic memory transistors, graphene oxide (GO) was utilized as the floating gate in 6,13-Bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene)-based organic memory transistors. A cross-linked, off-centre spin-coated and ozone-treated poly(methyl methacrylate) (cPMMA) was used as the insulating layer. High mobility and negligible hysteresis with very clear transistor behaviour were observed for the control transistors. On the other hand, memory transistors exhibited clear large hysteresis which is increased with increasing programming voltage. The shifts in the threshold voltage of the transfer characteristics as well as the hysteresis in the output characteristics were attributed to the charging and discharging of the floating gate. The counter-clockwise direction of hysteresis indicates that the process of charging and discharging the floating gate take place through the semiconductor/insulator interface. A clear shift in the threshold voltage was observed when different voltage pulses were applied to the gate. The non-volatile behaviour of the memory transistors was investigated in terms of charge retention. The memory transistors exhibited a large memory window (~30 V), and high charge density of (9.15 × 1011 cm−2).

Memristive Non-Volatile Memory Based on Graphene Materials

“…GO can be dispersed in a variety of solvents, which permits compatible processes with a wide range of commercially available flexible substrates. With various technologies like spin coating [164][165][166], drop casting [167][168][169], dip coating [170][171][172], and inkjet printing [157,173,174], GO dielectric layers can be deposited onto flexible substrates like polyethylene terephthalate (PET), polyether sulfone (PES), and polyimide [175][176][177][178][179][180]. In addition, the thickness of a single atomic layer and the excellent dispersibility in various solvents result in GO having enhanced compatibility with different commercial substrates [181][182][183].…”

Improving Photosensitivity and Transparency in Organic Phototransistor with Blending Insulating Polymers

“…TIPS-Pn is an organic semiconductor with high stability in the air and high solubility in organic solvents that exhibits good performance even at a low supply voltage [ 26 , 27 , 28 ]. In addition, the crystal growth of Pn molecules is highly dependent on the surface energy of the substrate; thus, the electrical performance of a device using TIPS-Pn can be readily adjusted by controlling Pn crystallization via the surface energy of the substrate or the evaporation rate of the solvent [ 29 , 30 , 31 ]. Similarly, PS was employed in the present study as an insulating polymer because of its advantageous binding properties, high insulating ability, and very high transparency [ 26 , 32 , 33 ].…”

Multifunctional Interfacial Layers from a One-Step Process for Effective Charge Capturing and Erasing in Low-Voltage-Driven Organic Thin-Film Transistors

“…The performance of OTFTs is dominated by the properties of active and dielectric layers. − For application in nonvolatile memory devices, a dielectric component that exhibits the function of charge storage is essential for OTFTs. Various types of dielectric materials, including ferroelectric polymer, − polymer electret, − nanoparticle/quantum dot, − conjugated molecule, − graphene oxide, − and ionic liquid, have been selected as the charge storage component of organic memory transistors (OMTs). For ferroelectric polymers, the polarization of the ferroelectric domains in the films can be affected by the external electric field during device programming, thereby changing the dielectric property of the polymer to modulate charge accumulation in the active channel and achieving data storage.…”