Ion beam mixing of Ag/Si bilayer

The Rutherford backscattering (RBS) technique has been used to study the io n-induced mixing of Ag thin film deposited onto Si substrates. The mixing w as initiated by a 400 keV Ar-40(+) beam by varying the dose up to 3 x 10(17 ) ions/cm(2) at constant flux of 0.6 mu A/cm(2). To assist the evaluation o f the results, all spectra were simulated. The RES spectra indicate that mi xing is initiated after a dose of 5 x 10(15) ions/cm(2) is reached. With pr ogressively increasing Ar dose to reach 1.6 x 10(17) ions/cm(2), the signal was noted to exhibit reduction of intensity accompanied by an increase of width and followed by long tail distributions, indicating a larger intermix ed region. At higher doses the RBS spectra indicate that the Ag top layer w as completely destroyed. The mixing rate parameters (or efficiencies) of Ag and Si were determined. Further insight into the mixing mechanism was gain ed by determining the diffusivities of both Ag and Si. Comparison between t heory and experiment reveals that Ag diffuses within Si according to the co llective effects resulting from thermal spike and thermally activated radia tion enhanced diffusion (RED) mechanisms.