ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Solid-state interdiffusions at the Ni/GaSb(111) and (001) interfaces were investigated in the temperature range 200–600 °C using 1.8 MeV He+ ion backscattering and channeling and also using x-ray diffraction. The starting point was the experimental determination of the Ni-Ga-Sb phase diagram. The steps of the interaction were the same for GaSb(111) and GaSb(001). Three various phases were observed: the ternary A phase with the Ni2.5GaSb atomic composition, Ni2Ga3, and Ni2Ga0.25Sb1.75, the Ga-rich limit of the substituted NiSb binary compound. All these phases had a hexagonal pseudocubic structure. First, an epitaxial Ni2.5GaSb A phase reacted layer was obtained. This phase was not in thermodynamical equilibrium with GaSb and the final product was a mixture of Ni2Ga3 and Ni2Ga0.25Sb1.75 grains with an average atomic composition equal to Ni1.6GaSb. The metallurgical behavior of the Ni/GaSb contacts was compared to that of the Ni/GaAs and Ni/AlAs contacts. It was concluded that the experimental ternary diagram allowed a correct estimation of the sequence of phase formation in metal/compound semiconductor contact. In contrast, due to major differences in the ternary phase diagrams, the steps of the solid phase interdiffusion cannot be deduced from the results obtained on a priori equivalent contacts.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.355748
Permalink
