ION-BEAM-INDUCED ATOMIC TRANSPORT AND PHASE-FORMATION IN THE SYSTEM NICKEL ANTIMONY .1. ION-BEAM MIXING OF BILAYERS AND MARKERS

We report on the ion-beam mixing processes of Sb/Ni marker layers and bilayers under the irradiation of ions ranging from He to Pb, at 80 K and at room temperature. The concentration profiles are obtained by Rutherford backscattering spectroscopy with 900 keV alpha-particles. At 80 K, the bilayer mixing rates cannot be reproduced by purely ballistic mixing; the essentially linear scaling of the bilayer mixing rate with the energy F(D) deposited at the interface points to local spike formation. A transition to global spike formation seems to be visible for the Pb-irradiations. Additional mixing effects at 300 K are due to radiation enhanced diffusion and scale with square-root F(D). The marker mixing rates at 80 K are reproduced by the ballistic mixing approach, but are equally well described by local spike models. High fluence Xe-irradiations of Sb/Ni bilayers lead to intermetallic phases in the interface region as verified by transmission electron microscopy.