Eco-friendly water-induced lithium oxide/polyethyleneimine ethoxylated as a possible gate dielectric of the organic field effect transistor

Abstract

It seems impossible to use silicon oxide as a suitable gate dielectric material in metal-oxide-semiconductor field effect transistors. Many researchers have studied various metal oxides, nitrides, composite, and hybrid materials in search of dielectric materials that can replace silicon oxide. Each of these materials has advantages and disadvantages. In the present work, water-induced Lithium oxide (LiO_x) with the organic PEIE (polyethylene imine ethoxylated) materials has been synthesized and studied. One advantage of the present work is using deionized water for getting (LiO_x) precursor solution from lithium nitrate without the use of any toxic additives, resulting in a low cost-effective and eco-friendly synthesis. By fabricating three organic field effect transistors (OFETs) with LiO_x/ PEIE nanocomposite materials with the same weight ratio (1:1), desirable electrical characteristics such as higher carrier mobility (μ) of 47.3 cm²V⁻¹ S⁻¹ , higher on-off current ratio (Ion/Ioff) of ∼10⁵ , minima threshold voltage (V_th) shift of ∼ 0.6 (±0.2) V, lower subthreshold swing (SS) of 3.12 mV/decade and lower tunneling-, and leakage current density (J) of 2 (nA/cm²) could be found which demonstrated eco-friendly water-induced LiO_x/ PEIE can be used as an alternative gate dielectric for the future of the OFET devices.