A novel gate insulator for flexible electronics

Abstract

Field effect transistors using a poly(triaryl amine) p-channel organic semiconductor in conjunction with anodised aluminium oxide as the gate insulator (Al2O3 on Al) are demonstrated. Anodised films are pinhole-free, homogenous oxide layers of precisely controlled thickness. The anodisation process requires no vacuum steps; anodised Al2O3 is insoluble in organic solvents, and Al films are cheaply available as laminates on flexible substrates. Anodised Al2O3 is confirmed to have high gate capacitance (≈60 nF/cm2) and electric breakdown strength (>3 MV/cm in the working device). This property profile answers to the demands on gate insulators for flexible electronics applications. © 2003 Elsevier Science B.V. All rights reserved.