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Fe/Ag multilayers, prepared by pulsed laser deposition (PLD) using KrF radiation, were characterized in-situ by RHEED (diffraction of high energetic electrons) and resistance measurements during deposition, and by X-ray diffraction after deposition. While the x-ray diffraction experiments give indications for sharp interfaces, the in-situ investigations clearly show an asymmetry of the structural behaviors at the interfaces and mixing effects on a nm scale, especially as soon as Fe is deposited on Ag. Time-of-flight (TOF) measurements performed with a Faraday cup show that during PLD in ultrahigh vacuum ions are deposited with kinetic energies of more than 100 eV. The results are modeled and discussed with respect to implantation and mixing effects due to the high kinetic energy of the deposited particles during PLD.

The properties of metallic thin films prepared by pulsed laser deposition (PLD) strongly differ from samples grown by conventional thin film techniques like sputtering and evaporation. In many systems (Fe-Nb, Fe-Zr, Cu-Co, Fe-Ag and Ni-Ag), strongly supersaturated solid solutions are formed, a broader formation range occurring for amorphous samples, and nanocrystalline phases are produced. Additionally, metastable phases of larger thickness at the interfaces of multilayers occur. Reasons for these behaviors are discussed with respect to atomic mixing and implantation effects induced by the high instantaneous deposition rate during PLD and the high kinetic energy (>100 eV) of the deposited ions.

The method of pulsed excimer laser ablation using KrF radiation was applied for the deposition of thin metallic elementary multilayers. Above an ablation threshold of about 5 J/cm2 an ‘explosive’ evaporation of the metallic targets occurs leading to high deposition rates of up to 5 nm/s. For different metals, the ablation threshold slightly varies leading at the same laser fluence to different growth rates as shown for Ag, Fe, Zr and Nb. By using two elementary targets and adjusting the dwelling times on both targets, Fe/Ag, Fe/Zr and Fe/Nb multilayers of different bilayer thicknesses were deposited. While Fe/Ag superstructures show crystalline phases down to a periodicity of 1 nm, Fe/Zr and Fe/Nb films are amorphous at such wavelengths. On the other side, Fe/Nb multilayers can also be amorphized by a solid state interdiffusion reaction of the elementary multilayers. The surfaces of the grown films are smooth except for a small number of droplets on the film surface.