The aim of this work is to perform an in-depth study of various materials by using the techniques of Scanning Tunnelling Microscopy (STM) and Spectroscopy (STS) at ambient air and temperature. First we have worked on graphite. We have obtained images of atomic resolution and observed that we only see every other atom. This problem, which is due to the atomic asymmetry of graphite, is discussed. We have then analysed this material by STS. The curves obtained confirm its semi-metallic behaviour. Then, we have analysed a sample of Au(111) that we have initially flame annealed. Again we have obtained the atomic resolution, which is more difficult than in the case of graphite because gold has a smaller corrugation. The obtained spectroscopy measurements clearly outline the metallic nature of this material. Finally, we have investigated at single wall carbon nanotubes. Those fullerenes possess outstanding electronic properties. They are particularly suited for a combined STM/STS study because they can be either metallic or semi-conductor nature depending upon their geometry. We have imaged ropes by STM and we have recorded spectroscopy curves that reveal semi-conducting nanotubes.
Etude des propriétés structurales et électroniques de matériaux métalliques et semi-conducteurs par microscopie et spectroscopie à effet tunnel: Study of the structural and electronic properties of metallic and semi-conductor materials by Scanning Tunnelling Microscopy and Spectroscopy
Sartenaer, Y. (Author). 2002
Student thesis: Master types › Master in Physics