Characterization of tungsten tips for STM by SEM/AES/XPS
نویسنده
چکیده
For the first time, both X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) techniques were applied in analysis of surface contamination of electrochemically etched Scanning Tunneling Microscope (STM) tungsten tips. Carbon monoxide, graphite, tungsten carbide and tungsten oxide were found as main surface contaminations of STM tungsten tips. The thickness of tungsten oxide layers was estimated to be about 1 3 nm. Quantitative analysis of surface and bulk concentration of carbon, oxygen and tungsten has been performed.
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