Structure and chemistry investigations of Ni3InAs thin film on InAs substrate

Abstract In situ X-Ray diffraction, Transmission Electron Microscopy (TEM) and Atom Probe Tomography (APT) were used to investigate the structure and the chemistry of the first phase formed after solid-state diffusive reaction between a Ni thin film (f) and an InAs substrate (s) at low temperature. The results show the formation of a single phase for which the Ni3InAs stoichiometry and the P63/mmc-hexagonal (a = b = 4.00 A and c = 5.10 A) structure were evidenced. Investigations in Electron Diffraction are in agreement with a disordered B8~1.5 structure in which additional Ni atoms are randomly distributed with In and As on the equivalent interstitial sites. The epitaxy relationship was also found, namely the [001]s//[210]f zone axes as well as the (220)s//(-120)f and (002)s//(100)f atomic planes. These findings were discussed taking into account atomic size effects.