Scanning Tunneling Microscopy Observation of WSe₂ Surface

Abstract

The surface structure of the WSe2 were studied using scanning tunneling microscopy. Exfoliation method in an ultra-high-vacuum chamber method is used to obtain a clean surface of WSe2 samples with atomically smooth terraces and multi-layer steps. Atomic-resolution images revealed two types of atomic defects of surface or near surface. These defects have been identified as the defects in the tungsten atom layer just below the topmost selenium layer.