Sb enhancement of lateral superlattice formation in GaInP

Epitaxial layers of GaInP were grown by organometallic vapor phase epitaxy with small amounts of TESb added to control the surface bonding. Above a co ncentration of Sb/III(v)=0.016, 12 K photoluminescence measurements show th at the band gap is reduced, as compared to completely disordered GaInP, by Sb addition and that polarization along the [(1) over bar 10] direction is as much as 41 times larger than along [110]. Transmission electron microsco py results show a lamellar domain structure in the [(1) over bar 10]-zone a xis dark-field images with a period of 120 nm. Atomic force microscopy show s surface undulations with the same period along the [(1) over bar 10] dire ction. The results demonstrate an increase in the magnitude of the presence of lateral composition modulation with increasing Sb concentration. (C) 20 01 American Institute of Physics.