Electronic properties of laterally confined n-GaAs/(AlGa)As heterostructures

Abstract We have investigated the magnetoresistance of laterally confined n-GaAs/(AlGa)As heterostructures in the temperature range from 2 to 300 K and at magnetic fields up to 11 T. Using a “shallow etch” technique, the 2DEG at the interface is confined to narrow channels which are 10 microm long and with lithographic widths between 0.16 and 0.54 microm. We assess the effectiveness of the confinement technique in terms of carrier depletion, the nature of the sidewall scattering and the stability of the conductivity as a function of time. We also compare the conduction channel and lithographic widths.