Black Phosphorus p-MOSFETs With 7-nm HfO₂Gate Dielectric and Low Contact Resistance

We report record contact resistance and transconductance in locally back-gated black phosphorus p-MOSFETs with 7-nm thick HfO 2 gate dielectrics. Devices with effective gate lengths, L eff , from 0.55 to 0.17 μm were characterized and shown to have contact resistance values as low as 1.14 ± 0.05 Q-mm. In addition, devices with L eff = 0.17 μm displayed extrinsic transconductance exceeding 250 μS/μm and ON-state current approaching 300 μA/μm.