All van der Waals Semiconducting PtSe 2 Field Effect Transistors with Low Contact Resistance Graphite Electrodes.

Contact resistance is a multifaceted challenge faced by the 2D materials community. Large Schottky barrier heights and gap-state pinning are active obstacles that require an integrated approach to achieve the development of high-performance electronic devices based on 2D materials. In this work, we present semiconducting PtSe 2 field effect transistors with all-van-der-Waals electrode and dielectric interfaces. We use graphite contacts, which enable high I ON / I OFF ratios up to 10 9 with currents above 100 μA μm -1 and mobilities of 50 cm 2  V -1  s -1 at room temperature and over 400 cm 2  V -1  s -1 at 10 K. The devices exhibit high stability with a maximum hysteresis width below 36 mV nm -1 . The contact resistance at the graphite-PtSe 2 interface is found to be below 700 Ω μm. Our results present PtSe 2 as a promising candidate for the realization of high-performance 2D circuits built solely with 2D materials.