Structural, electrical and optical properties of Si delta-doped Al_0.27Ga_0.73As/GaAs single quantum wells grown by metalorganic chemical vapour deposition

Transmission electron microscopy (TEM), capacitance-voltage (C-V), and photoluminescence (PL) measurements have been performed to characterize the properties of edge delta-doped and centre delta-doped Al_0.27Ga_0.73As/GaAs single quantum wells grown by metalorganic chemical vapour deposition. Direct observation of the Si delta-doped layer in GaAs quantum wells has been achieved by TEM, and the results of the C-V profiles indicate that the full width half-maximum value of centre delta-doped quantum wells is much narrow than that of edge delta-doped quantum wells. Temperature-dependent PL spectra of centre delta-doped quantum wells show the strong luminescence attributed to the Fermi edge singularity caused by enhanced confinement of carriers by the quantum well.