Ponente
Descripción
Scanning tunneling microscopy (STM) is a scanning probe microscopy (SPM) method that allows the study of conducting and semiconducting surfaces (pristine or with adsorbates) at the nanoscale, from a few micrometers up to atomic resolution. This technique allows also the manipulation of atoms and molecules and the modification of the surface, becoming a very useful tool in nanoscience and nanotechnology.
Due to its high precision, this microscope is very sensitive to external mechanical and electrical noise. The mechanical noise is damped by means of an adequate vibration isolation setup. Electrical noise can be attenuated with the correct shielding and grounding of wires and electronic equipment. Nevertheless, the complete removal of electrical noise is always a difficult task due to the variety of sources of it.
To characterize the electrical noise present in the home-made STM available at the IMRE, we have designed a computer program that takes temporal series of values of voltage proportional to the tunneling current and computes their Fourier series, allowing to the user characterize the electrical noises present in the STM, evaluate their sources and the effect of wires and tips on them.
