Scattering of electrons in the GaAs/AlAs transistor structure

Influence of surface roughness scattering on electron low-field mobility in thin undoped GaAs-in-Al2 O3 nanowires with rectangular cross-section

“…As in Refs. 13–15, 17, 18, 21, 22 let us assume that the total scattering probability is given by the sum of contributions from each boundary (interface). Such an assumption is completely valid if there is no correlation between the roughness profiles for different boundaries, i.e.…”

“…(1)–(3), (6) and (7), it is easy to derive the formulae where the averaging is carried out over all possible realizations of the random function g ( Λ , y ) specified by the autocorrelation function In Eq. (9), χ is the wave vector which corresponds to the collisional broadening factor ΔE 13 characterizing the collisional broadening of the electron energy spectrum due to all the scattering mechanisms under consideration 12–16.…”

“…So, for example, the physico‐mathematical basis by means of which one can create numerical models allowing the electrophysical parameters of thin GaAs quantum nanowires with rectangular cross‐section characterized by some physical (Fermi energy and temperature) and topological (geometrical) parameters to be calculated has been developed in Refs. 10–16 recently. Nevertheless there is a reason to think that this is not exactly so.…”

“…Nevertheless there is a reason to think that this is not exactly so. A reason is that such parameters as the root‐mean‐square deviation of a rough wire boundary from the plane δ 1D 13–15, 17 and the amplitude of roughness Δ 1D = 2 δ 1D 18 have been introduced to calculate the surface roughness scattering matrix elements under the assumption that the roughness potential depends only on the x ‐coordinate along the wire direction (axis) for any wire boundary. In connection with the assumption, δ 1D ( Δ 1D ) is the physical (fitting) parameter because it characterizes some averaged deviation of thickness of a real rectangular wire with rough boundaries for which the roughness potential depends on both the x ‐ and y ‐coordinates for two boundaries perpendicular to the z ‐axis, and depends on both the x ‐ and z ‐coordinates for two boundaries perpendicular to the y ‐axis.…”

“…So the main purpose of the study reported here was to calculate the electron low‐field mobility in thin undoped GaAs‐in‐Al 2 O 3 quantum nanowires with rectangular cross‐section using the physico‐mathematical models developed in Refs. 10–16 and to investigate the influence of surface roughness scattering on the mobility. Moreover, it is proposed to apply the parameter Δ 2D instead of the parameter Δ 1D during the calculation of surface roughness scattering matrix elements.…”