THEORETICAL INVESTIGATION OF IMPURITY SCATTERING LIMITED MOBILITY IN QUANTUM-WELLS - THE INFLUENCE OF WAVE-FUNCTION MODELING

A theoretical investigation of the impurity scattering limited mobility in quantum wells is presented. Emphasis is put on the influence of wave-function modeling, since the literature about this topic is contradictory. For an infinite square well, Dirac and sine wave functions yield the same evolutions of the mobility with temperature, carrier density, and well width. These results contradict those published by Lee [J. Appl. Phys. 54, 6995 (1983)], which are shown to be wrong. Self-consistent wave functions have also been used to compute the mobility in finite barrier height quantum wells. A strong influence of the presence of electrons inside the doped barrier has been demonstrated. It is suggested that, although simple models are useful for qualitative discussions, accurate evaluation of mobility requires a reasonably realistic description of wave functions.