Electronic properties of germanane field-effect transistors

Abstract

A new two dimensional (2D) material-germanane-has been synthesised recently with promising electrical and optical properties. In this paper we report the first realisation of germanane fieldeffect transistors fabricated from multilayer single crystal flakes. Our germanane devices show transport in both electron and hole doped regimes with on/off current ratio of up to 10 5 (10 4 ) and carrier mobilities of 150 cm 2 (V s) -1 (70 cm 2 (V s) -1 ) at 77 K (room temperature). A significant enhancement of the device conductivity under illumination with 650 nm red laser is observed. Our results reveal ambipolar transport properties of germanane with great potential for (opto)electronics applications.