Tungsten Diselenide Transistors: Layer Number Dependence, Channel Passivation and In‐Plane Gates

ABSTRACT High‐performance and few‐layer WSe 2 field‐effect transistors with p ‐type channels are fabricated through sequential mono‐layer WSe 2 film transferring. With 30 nm Al 2 O 3 passivation layer and polycrystalline gold electrodes, increasing field‐effect mobility values from 16.3 (1‐layer WSe 2 ), 45.4 (2‐layer WSe 2 ) to 81.3 (3‐layer WSe 2 ) cm 2 · V −1 · s −1 are observed with increasing…