A nuclear microprobe was used to study interdiffusion, between Ge and Pd in a lateral diffusion couple, by means of micro-beam Rutherford back-scattering spectrometry. When a Ge island which was 65nm thick was deposited onto a continuous 50nm-thick Pd film and was annealed (300C, 0.5h), the Pd/Ge ratios (as a function of position) implied that all 5 phases in the phase diagram (PdGe, Pd2Ge, Pd5Ge2, Pd3Ge, Pd5Ge) formed in, and around, the island; due mainly to the lateral diffusion of Ge. An investigation of concentration, as a function of depth within the thin films, revealed an unexpected concentration gradient. The presence of the concentration gradient could have been detected only by using micro-beam Rutherford back-scattering spectrometry.

Study of Pd/Ge Interaction in a Lateral Diffusion Couple by Micro-Beam Rutherford Back-Scattering Spectrometry. C.L.Churms, C.M.Comrie, R.S.Nemutudi: Nuclear Instruments & Methods in Physics Research B, 1999, 158[1-4], 713-6