Formation of Ni silicide at room temperature studied by laser atom probe tomography: Nucleation and lateral growth

The first stages of Ni silicides have been studied by laser assisted atom probe tomography. The observations were realized on a Ni alloyed with 5% of Pt film on (1 0 0)Si, at room temperature. Without any heating, it has been observed the formation of two phases with distinct compositions: a layer of relatively constant thickness about 2 nm, with a composition close to NiSi and a cluster of Ni2Si. These observations are in accordance with the nucleation followed by lateral growth model deduced from calorimetric measurement of silicides and intermetallics growth. The redistribution of Pt during the first stage of formation of the silicides has also been measured.