Epitaxial Growth and Band Structure of Te Film on Graphene

摘要

Tellurium (Te) films with monolayer and few-layer thickness are obtained bymolecular beam epitaxy on a graphene/6H-SiC(0001) substrate and investigated byin situ scanning tunneling microscopy and spectroscopy (STM/STS). We revealthat the Te films are composed of parallel-arranged helical Te chainsflat-lying on the graphene surface, exposing the (1x1) facet of (10-10) of thebulk crystal. The band gap of Te films increases monotonically with decreasingthickness, reaching ~0.92 eV for the monolayer Te. An explicit band bending atthe edge between the monolayer Te and graphene substrate is visualized. Withthe thickness controlled in atomic scale, Te films show potential applicationsof in electronics and optoelectronics.