Reliable High-Quality Metal-Embedded h-BN Contacts to p-type WSe2

Two-dimensional (2D) materials have been widely studied due to their unique properties for next-generation electronic applications. Recently, transition metal dichalcogenides (TMDs) have shown promise due to their large band gaps (> 1 eV) as compared to graphene [1]. So far, Mos2 has received the most attention among TMD materials as an n-type semiconductor [2]. WSe2 is a strong candidate for a p-type 2D semiconductor due to its high field effect hole mobility as high as 500 cm2/(y·s) has been extracted from room-temperature four-terminal measurements and higher oxidation resistance compared to Mos2 [3–4], however, the large bandgap of ultra-thin WSe2 makes forming an ohmic contact difficult. Here, we describe the fabrication of metal-embedded h-BN contacts and show electrical results that demonstrate that this process yields high-quality contacts to bilayer WSe2 p-FETs.