Deep level defects in GaAs1−xBix/GaAs heterostructures

Deep level transient spectroscopy (DLTS) measurements were performed on p–i–n diodes having i-regions that include a GaAs1−xBix layer sandwiched between two GaAs layers, all grown at T < 400 °C. A GaAs1−xBix/GaAs heterostructure with Bi fraction x = 4.7% grown at 285 °C was found to have several traps in concentrations of ~5 × 1015 cm−3. The location of the observed traps in the i-region is determined from simulations of the band diagrams of these devices at the bias conditions used for the DLTS measurements and confirmed by DLTS spectra taken at various filling voltages.