Active nanocharacterization of nanofunctional materials by scanning tunneling microscopy

Abstract

Recent developments in the application of scanning tunneling microscopy (STM) to nanofabrication and nanocharacterization are reviewed. The main focus of this paper is to outline techniques for depositing and manipulating nanometer-scale structures using STM tips. Firstly, the transfer of STM tip material through the application of voltage pulses is introduced. The highly reproducible fabrication of metallic silver nanodots and nanowires is discussed. The mechanism is thought to be spontaneous point-contact formation caused by field-enhanced diffusion to the apex of the tip. Transfer through the application of z-direction pulses is also introduced. Sub-nanometer displacement pulses along the z-direction form point contacts that can be used for reproducible nanodot deposition. Next, the discovery of the STM structural manipulation of surface phases is discussed. It has been demonstrated that superstructures on Si(001) surfaces can be reverse-manipulated by controlling the injected carriers. Finally, the fabrication of an atomic-scale one-dimensional quantum confinement system by single-atom deposition using a controlled point contact is presented. Because of its combined nanofabrication and nanocharacterization capabilities, STM is a powerful tool for exploring the nanotechnology and nanoscience fields.

Directed and On‐Demand Alignment of Carbon Nanotube: A Review toward 3D Printing of Electronics

“…Normally, the alignment of the as‐grown CNTs films or arrays can be evaluated visually by microscopy technique such as atomic force microscopy (AFM), scanning electron microscopy (SEM), scanning tunneling microscopy (STM), and polarizing microscopy . This technique is especially suitable for samples that have a very thin thickness and low CNTs density which cannot be inspected effectively using other laser‐based or X‐ray‐based technique.…”

Epitaxial Graphene on Metals

“…Rotation of the sample by an angle f3 produces the 30 data set of experimental photoemission intensity, /(Ekin , k. t> k y), where kx and k y are in-plane components of the wave-vector calculated from the experimental geometry. (d) In spin-resolved PES experiments, 20 CCO detector from (c) is replaced by a spin detector (usually classical or mini Mott type) where spin-separation is performed of surface topography and atomic arrangement, STM is usually implemented (for details, see [54,55] and Chap. 3).…”

Techniques of aligning carbon nanotubes

“…Alignment of as-grown CNTs is commonly evaluated using atomic force microscopy (AFM) [34], scanning tunneling microscopy (STM) [35] or scanning electron microscopy (SEM) [36][37][38]. Transmission electron microscopy (TEM) [39,40] is less suitable because it requires relatively complex sample preparation, which can modify the CNT arrangement.…”