Organic small molecule field-effect transistors with Cytop(TM) gate dielectric: eliminating gate bias stress effects

TL;DR

This paper demonstrates that organic field-effect transistors with Cytop dielectric exhibit exceptional resistance to gate bias stress, maintaining stable performance and showing no fundamental limitations for organic semiconductor stability.

Contribution

It introduces the use of Cytop as a gate dielectric in organic transistors, significantly enhancing their stability against gate bias stress compared to previous materials.

Findings

High electrical quality of single crystal transistors

Minimal changes under extended gate bias stress

Negligible current hysteresis and steep subthreshold swing

Abstract

We report on organic field-effect transistors with unprecedented resistance against gate bias stress. The single crystal and thin-film transistors employ the organic gate dielectric Cytop(TM). This fluoropolymer is highly water repellent and shows a remarkable electrical breakdown strength. The single crystal transistors are consistently of very high electrical quality: near zero onset, very steep subthreshold swing (average: 1.3 nF V/(dec cm2)) and negligible current hysteresis. Furthermore, extended gate bias stress only leads to marginal changes in the transfer characteristics. It appears that there is no conceptual limitation for the stability of organic semiconductors in contrast to hydrogenated amorphous silicon.