PREPARATION OF THIN-FILMS OF THE TERNARY HEAVY-FERMION SYSTEM CENI2GE2

We investigated the growth, structure, and electronic properties of th in CeNi2Ge2 layers on W(110). In order to produce well-ordered and ato mically clean surfaces of the Ce-based intermetallic system the growth was performed under UHV conditions (p < 2 x 10(-11) mbar). Both the p olycrystalline CeNi2Ge2 compound and the individual elements Ce, Ni, a nd Ge were used as evaporants. The characterisation of the layers was made with LEED, SEM, and XPS. We find a significant influence of the s ubstrate temperature and the evaporation power on the growth character istics. The compound material CeNi2Ge2 exhibits complicated behaviour when evaporated. Under carefully selected growth conditions we obtain well-ordered films with a stoichiometry of Ce:Ni:Ge = 1 : 2 : 2 and a (001) oriented surface of the body-centered tetragonal ThCr2Si2-type s tructure. The k(parallel to) dispersion and binding energies of the va lence bands of these lavers were determined with ARUPS.