Study of factors limiting electron mobility in InSb quantum wells

We observe a significant increase in InSb quantum-well mobility when remote doping of Al0.09In0.91Sb barriers is accomplished by three layers, rather than one layer, of Si δ doping. At 7 K, the electron mobility in single quantum-well structures grown on GaAs substrates is as high as 280 000 cm2/V s with an electron density of 2.33×1011 cm−2. The density of oriented abrupt steps and square-mound features on the sample surface correlates with the electron mobility in the well.