COMBINED HRLEED AND STM INVESTIGATIONS ON THE INITIAL-STAGES OF CU HETEROEPITAXY ON RU(0001)

Recent scanning tunneling microscopy (STM) observations revealed diffe rent layer structures in the heteroepitaxial Cu/Ru(0001) system with i ncreasing film thickness attributed to various stages of strain relaxa tion. High-resolution low-energy electron diffraction (HRLEED) analysi s permits one to derive more exactly both lattice periodicities and la ttice rotations. Furthermore, the representative character of local ST M results can be proved. However, STM measurements are needed to ident ify and to assign the satellite spots to coexistent different superstr uctures which are superposed incoherently in the diffraction pattern. Generally, the integral LEED results confirm the crystallographic data obtained by STM in a local scale.