Structural Asymmetry related Nonlinear Mobility of Electron in InxGa1-xAs/GaAs Quantum well FET

Abstract

Nonlinear characteristics in the mobility µ of electrons in InxGa1-xAs/GaAs pseudomorphic quantum well FET structure is studied. We vary the doping concentrations in the barriers, nd1 (substrate) and nd2 (surface), keeping the sum (nd1+nd2) unchanged. This induces an asymmetric distribution of subband wave functions within the well, thereby influencing the subband electron mobilities through intersubband effects. The resultant asymmetric variation of µ is dependent on interface roughness scattering, while the alloy disorder and impurity scatterings govern the total magnitude of µ.