Characterization of Local Electronic Transport through Ultrathin Au/Highly-Dense Si Nanocolumnar Structures by Conducting-Probe Atomic Force Microscopy

摘要

We have fabricated highly-dense Si nano-columnar structures accompanied with Si nanocrystals on W-coated quartz, and characterized their local electrical transport in the thickness direction using atomic force microscopy (AFM) with a conductive cantilever. By applying DC negative bias to the bottom W electrode with respect to a grounded top electrode made of ～10-nm-thick Au on the sample surface, current images reflecting highly-localized conduction were obtained in both contact and non-contact modes. This result is attributable to electron emission due to quasi-ballistic transport through Si nanocrystals via nanocolumnar structure.