Original Article

A surface-potential-based electrical model for amorphous InGaZnO electric-double-layer transistors with electrolyte insulation

¹ College of Electronic Information and Physics, Central South University of Forestry and Technology, Changsha 410004, P.R. China
² College of Mathematics and Physics, Hunan University of Arts and Science, Changde 415000, P.R. China

^* e-mail: xprolive@126.com

Received: 8 August 2024
Accepted: 7 February 2025
Published online: 27 February 2025

Abstract

The electric-double-layer transistors (EDLTs) have attracted much attention on achieving ultra-high-density charge accumulation and low operating voltage due to their huge capacitance in electrolyte insulation. A surface-potential-based electric-double-layer (EDL) capacitance and drain current model for amorphous InGaZnO EDLTs is proposed in this paper. It is demonstrated that the EDL capacitance, which includes compact layer and diffuse layer capacitance, is affected not only by the ionic characteristics of the electrolyte, but also by the partial voltage of the gate voltage V_GS. The calculated drain current shows good consistency with the reported experimental data. Finally, the effect of the ionic density c and the occupancy of electrolyte capacity on EDL capacitance, surface potential and drain current in the amorphous InGaZnO EDLTs are analyzed with the V_GS-dependent EDL capacitance taken into consideration.