Interface roughness scattering in InGaAs/InAlAs double quantum wells grown on (100) and (411)A InP substrates at different growth temperatures

We compare the interface roughness scattering of electrons at the In0.53Ga0.47As/In0.52Al0.48As heterointerface simultaneously grown on (100) and (411)A oriented InP substrates using gas-source molecular-beam epitaxy (MBE). A modulation-doped double quantum well structure is designed to emphasize the effects of interface scattering. The transport properties for both (100) and (411)A orientations are compared for different MBE growth temperatures. The highest mobilities on (411) oriented structures are 40% higher than those on (100) oriented structures, indicating less electron scattering due to interface roughness scattering.