QUANTUM CONFINEMENT EFFECTS ON LOW-DIMENSIONAL ELECTRON-MOBILITY

A study of quantum confinement effects on the low-dimensional electron mobility in various AlGaAs/GaAs quantum well/wire structures has been performed. The influence of the electron envelop wave function and th e subband structure on the low-dimensional electron scattering rates i s evaluated. The electron transport behavior is studied through a Mont e Carlo simulation. The result shows that the low-dimensional electron mobility varies significantly with the quantum well/wire geometry. Th e one-dimensional electron mobility of 9200 cm2/V s is obtained in a r ectangular quantum wire with a geometry of 110 angstrom X 110 angstrom . This value is much improved in comparison with the bulk electron mob ility of 8000 cm2/V s in intrinsic GaAs and the maximum two-dimensiona l electron mobility of 8600 cm2/V s in a 120 angstrom GaAs quantum wel l. It is also noticed that the highest low-dimensional electron mobili ty is achieved in a quantum well/wire structure where the energy separ ation between the first subband and the second subband is about two po lar optical phonon energy.