Fabrication of [001]-oriented tungsten tips for high resolution scanning tunneling microscopy
نویسندگان
چکیده
The structure of the [001]-oriented single crystalline tungsten probes sharpened in ultra-high vacuum using electron beam heating and ion sputtering has been studied using scanning and transmission electron microscopy. The electron microscopy data prove reproducible fabrication of the single-apex tips with nanoscale pyramids grained by the {011} planes at the apexes. These sharp, [001]-oriented tungsten tips have been successfully utilized in high resolution scanning tunneling microscopy imaging of HOPG(0001), SiC(001) and graphene/SiC(001) surfaces. The electron microscopy characterization performed before and after the high resolution STM experiments provides direct correlation between the tip structure and picoscale spatial resolution achieved in the experiments.
منابع مشابه
High resolution STM imaging with oriented single crystalline tips
Precise knowledge of the atomic and electronic structure of scanning tunneling microscopy (STM) tips is crucial for correct interpretation of atomically resolved STM data and improvement of spatial resolution. Here we demonstrate that tungsten probes with controllable electronic structure can be fabricated using oriented single crystalline tips. High quality of the [001]-oriented W tips sharpen...
متن کاملOptimization of Electrochemical Etching Parameters in FIM/STM Tungsten Nanotip Fabrication
Field Ion Microscopy (FIM) and Scanning Tunneling Microscopy (STM) have found a wide application in nanotechnology. These microscopes use a metallic nanotip for image acquisition. Resolution of FIM and STM images depends largely on the radius of nanotip apex; the smaller the radius the higher the resolution. In this research, for tungsten nanotip fabrication, electrochemical etching of tungsten...
متن کاملTip preparation for usage in an ultra-low temperature UHV scanning tunneling microscope
This work deals with the preparation and characterization of tungsten tips for the use in UHV low-temperature scanning tunneling microscopy and spectroscopy (STM and STS, respectively). These specific environments require in situ facilities for tip conditioning, for further sharpening of the tips, as well as for reliable tip characterization. The implemented conditioning methods include direct ...
متن کاملSelf-Limiting Adsorption of WO3 Oligomers on Oxide Substrates in Solution
Electrochemical surface science of oxides is an emerging field with expected high impact in developing, for instance, rationally designed catalysts. The aim in such catalysts is to replace noble metals by earth-abundant elements, yet without sacrificing activity. Gaining an atomic-level understanding of such systems hinges on the use of experimental surface characterization techniques such as s...
متن کاملTheoretical study of carbon-based tips for scanning tunnelling microscopy.
Motivated by recent experiments, we present here a detailed theoretical analysis of the use of carbon-based conductive tips in scanning tunnelling microscopy. In particular, we employ ab initio methods based on density functional theory to explore a graphitic, an amorphous carbon and two diamond-like tips for imaging with a scanning tunnelling microscope (STM), and we compare them with standard...
متن کامل