STM AND SYNCHROTRON-RADIATION STUDIES OF PROTOTYPICAL METAL-SEMICONDUCTOR SYSTEMS

Since the origin of surface science noble metal/elemental semiconducto r couples have been considered as ''prototypical'' systems. After thre e decades of research their structural and electronic properties remai n an intriguing maze despite recent advances made, especially thanks t o the development of the near-field microscopies and the ''tensive use of synchrotron radiation in surface crystallography and in high-resol ution photoelectron spectroscopy. In the last few years, lead, as a re placement inert metal, has nearly gained the pole position in the disp lay of exotic behaviour. This paper gives a flavour of this mystery st ory and highlights some puzzling questions.