Hydrogenation of InAs on GaAs heterostructures

Atomic hydrogen has been introduced from a plasma source into InAs layers grown by molecular beam epitaxy on GaAs substrates. It is shown that hydrogen diffuses very fast into this material. The presence of hydrogen modifies the electronic transport properties, the near-band-edge luminescence spectra, and the far-infrared reflectivity spectra. The most striking effect is that, unlike other III-V compounds, the free-carrier density increases by one order of magnitude after hydrogenation. These phenomena are reversible and thermal annealing restores the original properties of the samples. Finally, models are proposed to explain the experimental results.