Electrical transport quantum effects in the In0.53Ga0.47As/In0.52Al0.48As heterostructure on silicon

Abstract
Electrical transport in a modulation doped heterostructure of In0.53Ga0.47As/In0.52Al0.48As grown on Si by molecular beam epitaxy has been measured. Quantum Hall effect and Subnikov–De Haas oscillations were observed indicating the two-dimensional character of electron transport. A mobility of 20 000 cm2/V s was measured at 6 K for an electron sheet concentration of 1.7×1012 cm−2. Transmission electron microscopy observations indicated a significant surface roughness and high defect 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 properties.