B diffusion in implanted Ni2Si and NiSi layers

B diffusion in implanted Ni2Si and NiSi layers has been studied using secondary ion mass spectrometry, and compared to B redistribution profiles obtained after the reaction of a Ni layer on a B-implanted Si(001) substrate, in same annealing conditions (400-550 degrees C). B diffusion appears faster in Ni2Si than in NiSi. The B solubility limit is larger than 10(21) atom cm(-3) in Ni2Si, while it is similar to 3x10(19) atom cm(-3) in NiSi. The solubility limit found in NiSi is in agreement with the plateau observed in B profiles measured in NiSi after the reaction of Ni on B-implanted Si

Further insights into the growth mechanism of the non-stoichiometric θ-Ni2Si phase

International audienceThe solid state reaction of 50 nm Ni with Si(100) substrate was investigated using in situ X-ray diffraction (XRD). The sequence is simultaneous; it begins by δ-Ni2Si phase then the metastable θ-Ni2Si phase is formed. Both phases grow simultaneously. The growth mechanism of the non-stoichiometric θ-Ni2Si phase is discussed on the basis of the evolution of its XRD peak during annealing. The results show that, during its growth, the non-stoichiometric θ-Ni2Si phase is split into two regions of different concentrations. This “original” behavior is justified by the discontinuous variation with composition of both the diffusion coefficient and the d-lattice spacing through the θ-Ni2Si phase

Reaction paths of Ni rich phases: Effect of Ni thickness

International audienceThe kinetics of growth and consumption of Ni-rich phases is determined from in situ X-ray diffraction measurements performed during isothermal annealing. The results show that the life time of theta-Ni2Si depends on the initial Ni thickness. A slow kinetic of consumption of theta-Ni2Si is observed during the reaction of 50 nm Ni with Si substrate, while a fast rate of consumption of theta-Ni2Si is observed when theta-Ni2Si is a transient phase. A qualitative model has been proposed to explain the obtained results. (C) 2017 Elsevier Ltd. All rights reserved

Arsenic clustering during formation of the transient Ni silicide

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Kinetics of growth and consumption of Ni rich phases

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