Reproducible Low Contact Resistance in Rubrene Single-Crystal Field-Effect Transistors with Nickel Source and Drain Electrodes

TL;DR

This study demonstrates that Nickel electrodes significantly reduce and improve the reproducibility of contact resistance in rubrene single-crystal FETs, outperforming Gold in stability and consistency.

Contribution

It introduces Nickel as a superior electrode material for organic FETs, achieving low and reproducible contact resistance through systematic scaling experiments.

Findings

Nickel contacts achieve as low as 100 Ωcm contact resistance.

Nickel electrodes show superior reproducibility over Gold.

Reproducibility is improved with narrowly spread fluctuations.

Abstract

We have investigated the contact resistance of rubrene single-crystal field-effect transistors (FETs) with Nickel electrodes by performing scaling experiments on devices with channel length ranging from 200 nm up to 300 $\mu$m. We find that the contact resistance can be as low as 100 $\Omega$cm with narrowly spread fluctuations. For comparison, we have also performed scaling experiments on similar Gold-contacted devices, and found that the reproducibility of FETs with Nickel electrodes is largely superior. These results indicate that Nickel is a very promising electrode material for the reproducible fabrication of low resistance contacts in organic FETs.