Characterization of metal contacts for two-dimensional MoS_2 nanoflakes

摘要

While layered materials are increasingly investigated for their potential in nanoelectronics, their functionality and efficiency depend on charge injection into the materials via metallic contacts. This work explores the characteristics of different metals (aluminium, tungsten, gold, and platinum) deposited on to nanostructured thin films made of two-dimensional (2D) MoS_2 flakes. Metals are chosen based on their work functions relative to the electron affinity of MoS_2. It is observed, and analytically verified that lower work functions of the contact metals lead to smaller Schottky barrier heights and consequently higher charge carrier injection through the contacts.