Résumé
Electrical properties of non-intentionally doped (nid) InAs/GaSb Superlattice (SL) structures and p-nid-n detectors grown by Molecular Beam Epitaxy on GaSb substrate are reported. The SL structures were made of 600 periods of 8 InAs monolayers (MLs) and 8 GaSb MLs, for a total thickness of 3 mu m. This structure exhibited a cutoff wavelength in the midwave infrared (MWIR) domain, near 4.7 mu m at 80K. Electrical transport measurements, based on resistivity and Hall Effect measurements, were performed on SL structure after removing the conducting GaSb substrate with an appropriate technological process. Carrier concentrations and mobilities carried out as a function of temperature (77-300K) for magnetic fields in the 0-1 Tesla range are analyzed. A change in type of conductivity is observed. The nid SL layers is p-type at liquid Nitrogen temperature while is n-type at room temperature. These results are completed with diode characterizations based on current-voltage (I-V) and capacitance-voltage (C-V) measurements performed on p-nid-n devices with identical InAs/GaSb SL active zone.