Improving contact resistance in MoS2 field effect transistors

MoS2 is a material of interest for two-dimensional (2D) field effect transistors (FETs) [1-3], however contact resistance (R
c
) remains a key limiting factor. Here we present a systematic study of contact resistance to MoS2 using various metals with different deposition conditions, compared to detailed simulations. We find that decreasing the metal deposition pressure improves the metal-MoS2 interface and brings R
c
for Au contacts to <1 kΩ-μm, which is lower than previous reports with Ni, Sc, or Au [1,4]. Comparison to simulations suggest that while the contact resistivity is reasonably good (ρc ≈ 5·10
⁻⁷
Ω·cm
²
), the lateral access resistance limits Rc in M0S2 FETs. This study is crucial for scalability of MoS2 devices, also suggesting methods to further improve Rc.