Impact of Gate Size on Abnormal Current Rise Under an Electric Field in Organic Thin-Film Transistors

This article investigates the effects of different gate sizes on the electrical characteristics of top-gate organic thin-film transistors. During electrical measurements, an abnormal phenomenon is observed. For a fixed channel length, the current increases with the increasing gate length. In narrow-gate channel devices, gates are used to control carriers of low current density through the side channel area. However, the wide-gate length devices can effectively reduce contact resistance and control large side channels. In this article, integrated systems engineering-technology computer-aided design (ISE-TCAD) simulations were performed for this device containing an active layer with gate cladding. The strength of the electric field extended to the surrounding channel, and the active layer was affected by the cross-wall electric field. The ON-current, under the action of the electric field, improved as the current density of the side channel increased.