Properties of center and edge δ-doped GaAs-AlGaAs quantum wells grown by metalorganic chemical vapor deposition

Abstract

We have investigated the properties of center and edge δ-doped GaAs-AlGaAs quantum wells grown by atmospheric pressure metalorganic chemical vapor deposition (MOCVD) by means of capacitance voltage (C-V) profiling and temperature-dependent photoluminescence (PL) measurements. For the center δ-doped quantum well, a narrow C-V profile and the Fermi-edge singularity in PL have been confirmed. In contrast, for edge δ-doped quantum wells, a double-peaked C-V profile and a sharp luminescence enhancement near the Fermi level which is not due to the Fermi-edge singularity, have been observed. The results are explained by a simple model based on the asymmetrical potential well induced by the band bending due to the δ-doping at one side of the heterointerfaces.