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Highlights: [•] Two methods of NW preparation have been proposed for NWs analysis by APT. [•] These methods were tested and reconstructed volumes for different kind of NWs. [•] Ni silicide formed on Si nanowire has been analyzed by atom probe tomography. [•] δ-Ni2Si is the only phase formed on Si NW and substrate after 200°C during 1h. [•] Au is localized at Ni/silicide interface after silicidation suggesting Ni diffusion. [ABSTRACT FROM AUTHOR]

Highlights: [•] APT analysis of Ni(Pt) contact of gate and source of 45 and 28nm transistors. [•] In 45nm transistor source, the transformation of δ-Ni2Si to NiSi does not occur. [•] Absence of NiSi in the source is related to the difficulty of nucleation on mono-Si. [•] The Pt redistribution during silicidation in the both cases is discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Possibilities and limitations of atom probe tomography for metallization are described. [•] APT for different materials for metallization (silicide, high K/metal gate…) are shown. [•] Preparation and analysis by APT of transistors and nanowires are presented. [ABSTRACT FROM AUTHOR]

Metallic silicides have been used as contact materials on source/drain and gate in metal-oxide semiconductor (MOS) structure for 40 years. Since the 65 nm technology node, NiSi is the preferred material for contact in microelectronic due to low resistivity, low thermal budget, and low Si consumption. Ni(Pt)Si with 10 at.% Pt is currently employed in recent technologies since Pt allows to stabilize NiSi at high temperature. The presence of Pt and the very low thickness (<10 nm) needed for the device contacts bring new concerns for actual devices. In this work, in situ techniques [X-ray diffraction (XRD), X-ray reflectivity (XRR), sheet resistance, differential scanning calorimetry (DSC)] were combined with atom probe tomography (APT) to study the formation mechanisms as well as the redistribution of dopants and alloy elements (Pt, Pd...) during the silicide formation. Phenomena like nucleation, lateral growth, interfacial reaction, diffusion, precipitation, and transient phase formation are investigated. The effect of alloy elements (Pt, Pd...) and dopants (As, B...) as well as stress and defects induced by the confinement in devices on the silicide formation mechanism and alloying element redistribution is examined. In particular APT has been performed for the three-dimensional (3D) analysis of MOSFET at the atomic scale. The advances in the understanding of the mechanisms of formation and redistribution are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Atom probe tomography was used to study the redistribution of platinum during Ni(10at.%Pt) silicidation of n-doped polycrystalline Si. These measurements were performed after the two annealing steps of standard salicide process both on a field-effect transistor and on unpatterned region submitted to the same process. Very similar results are obtained in unpatterned region and in transistor gate contact. The first phase to form is not the expected δ-Ni2Si but the non stoichiometric θ-Ni2Si. Pt redistribution is strongly influenced by this phase and the final distribution is different from what is reported in literature. [Copyright &y& Elsevier]

Abstract: Different FIB-based sample preparation methods for atom probe analysis of transistors have been proposed and discussed. A special procedure, involving device deprocessing, has been used to analyze by APT a sub-30nm transistor extracted from a SRAM device. The analysis provides three dimensional compositions of Ni-silicide contact, metal gate and high-k oxide of the transistor gate. [Copyright &y& Elsevier]