ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The ohmic contact formation mechanism in furnace alloyed Ni/Au/Te/Au/GaAs structures is investigated by the combined application of x-ray diffraction and Raman spectroscopy. It was found that the Ni top layer promotes a more uniform dissociation of the GaAs substrate by the formation of a ternary Nix GaAs phase in the initial stages of contact formation (T=350 °C). At an alloy temperature T=550 °C, which induces low resistive electrical behavior, the formation of epitaxial Ga2Te3 was observed, indicating the formation of a Ga2Te3/GaAs heterojunction. After alloying at 600 °C, Ga2Te3 was still found to be present in the contact zone. In addition, evidence for a regrowth of GaAs crystallites could be derived from an increase of the intensity ratio ITO/ILO of the GaAs Raman signals. No indication for the presence of a high density of shallow donors ((approximately-greater-than)1019 cm−3) in the GaAs top layers could be adduced.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.356308
