Phase formation between Ni thin films and GaAs substrate

International audienc

Phase formation between Ni thin films and GaAs substrate

International audienc

Pdge Contact Fabrication On Se-Doped Ge

PdGe contact fabrication on Se-doped Ge(001) is investigated. PdGe thin film resistivity is two times lower if the PdGe layer is grown by Pd reactive diffusion on Se-doped Ge, compared to PdGe layer grown in the same condition on Se-free Ge. The phase sequence and the phase growth kinetics during Pd reactive diffusion with Ge are not modified by the presence of Se atoms. However, the PdGe film texture is different with Se, and Se segregates at the PdGe/Ge interface. These results suggest that Se atoms may be used to produce efficient contacts on n-type Ge

Croissance des intermétalliques à l’interface Ni/GaAs

International audienc

Phase formation between Ni thin films and GaAs substrate

International audienceIn situ X-Ray Diffraction, X-Ray Reflectivity and High Resolution Transmission Electron Microscopy were used to investigate the sequence and the texture of phase formation during the solid-state reaction of Ni thin film with GaAs substrate. These results show the formation of a unique Ni3GaAs crystalline phase at 200 degrees C that remains stable until 400 degrees C. The epitaxial relationships between this phase and the GaAs substrate were also evidenced. The formation of this unique phase, along with the variation of its lattice parameters when Ni is totally consumed, can be explained by local thermodynamic equilibrium and kinetics arguments. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved

PdGe contact fabrication on Se-doped Ge

International audiencePdGe contact fabrication on Se-doped Ge(001) is investigated. PdGe thin film resistivity is two times lower if the PdGe layer is grown by Pd reactive diffusion on Se-doped Ge, compared to PdGe layer grown in the same condition on Se-free Ge. The phase sequence and the phase growth kinetics during Pd reactive diffusion with Ge are not modified by the presence of Se atoms. However, the PdGe film texture is different with Se, and Se segregates at the PdGe/Ge interface. These results suggest that Se atoms may be used to produce efficient contacts on n-type Ge. (c) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved