Enhancement of multisubband electron mobility in an asymmetric coupled quantum well based inverted MODFET structure

Abstract

The effect of asymmetry in the structure parameters on the low temperature multisubband electron mobility in an inverted MODFET structure is analyzed. We obtain the subband energy levels and wave functions through selfconsistent solution of Schrodinger and Poisson's equations. We consider ionized impurity scattering, interface roughness scattering and alloy disorder scattering to calculate the electron mobility. The asymmetric variation of doping concentration and well width significantly influences the interplay of scattering mechanisms in a multisubband occupied system. We show that the electron mobility is enhanced considerably with increase in barrier width under double subband occupancy when well width is small (<110 A). We also show that the asymmetry in doping concentrations (with less doping towards the inverted interface) leads to enhancement in mobility.