On the annealing mechanism of AuGe/Ni/Au ohmic contacts to a two-dimensional electron gas in GaAs/AlxGa1-xAs heterostructures

@article{Koop2013OnTA,
  title={On the annealing mechanism of AuGe/Ni/Au ohmic contacts to a two-dimensional electron gas in GaAs/AlxGa1-xAs heterostructures},
  author={E. J. Koop and Muhammad Javaid Iqbal and Friederich Limbach and M. C. Boute and Bart Jan van Wees and Dirk Reuter and Andreas Dirk Wieck and Bart J. Kooi and Caspar H. van der Wal},
  journal={Semiconductor Science and Technology},
  year={2013},
  volume={28},
  pages={025006}
}
Ohmic contacts to a two-dimensional electron gas (2DEG) in GaAs/AlxGa1 ? xAs heterostructures are often realized by annealing of AuGe/Ni/Au that is deposited on its surface. We studied how the quality of this type of ohmic contact depends on the annealing time and temperature, and how optimal parameters depend on the depth of the 2DEG below the surface. Combined with transmission electron microscopy and energy-dispersive x-ray spectrometry studies of the annealed contacts, our results allow for… 

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