ELECTRICAL-TRANSPORT QUANTUM EFFECTS IN THE IN0.53GA0.47AS IN0.52AL0.48AS HETEROSTRUCTURE ON SILICON/

Electrical transport in a modulation doped heterostructure of In0.53Ga 0.47As/In0.52Al0.48As grown on Si by molecular beam epitaxy has been m easured. Quantum Hall effect and Subnikov-De Haas oscillations were ob served indicating the two-dimensional character of electron transport. A mobility of 20 000 cm2/V s was measured at 6 K for an electron shee t concentration of 1.7 X 10(12) cm-2. Transmission electron microscopy observations indicated a significant surface roughness and high defec t density of the InGaAs/InAlAs layers to be present due to the growth on silicon. In addition, fine-scale composition modulation present in the In0.53Ga0.47As/In0.52Al0.48As may further limit transport properti es.