Structural and electronic properties of doped InP/InGaAs short period superlattices grown by LP-MOVPE

We have studied the structural and electronic properties of lattice-matched InP/InGaAs superlattices with planar doping with Si in the center of the b arrier layers, using X-ray spectroscopy, transport and photoluminescence (P L) measurements. The formation of superlattice minibands can be seen in the Shubnikov-de Haas (SdH) spectra. The PL spectra show an emission band at h igh energies, which is associated with carriers confined by the superlattic e. As the thickness of the barriers was made smaller, the SdH oscillations decreased in frequency and the PL high-energy emission band narrowed, due t o a reduction in the density of free carriers. A possible cause for this is the greater probability of the Si atoms being incorporated into acceptor s ites, located within the interface layers, in samples with thinner barriers . (C) 1999 Elsevier Science B.V. All rights reserved.