Open AccessПодвижность двумерного электронного газа в DA-pHEMT гетроструктурах с различной шириной профиля delta-n-слоев
Author(s) -
Д.Ю. Протасов,
А.К. Бакаров,
А.И. Торопов,
Б.Я. Бер,
Д.Ю. Казанцев,
К.С. Журавлев
Publication year - 2018
Publication title -
fizika i tehnika poluprovodnikov
Language(s) - English
Resource type - Journals
eISSN - 1726-7315
pISSN - 0015-3222
DOI - 10.21883/ftp.2018.01.45318.8610
Subject(s) - heterojunction , high electron mobility transistor , electron mobility , scattering , materials science , doping , condensed matter physics , effective mass (spring–mass system) , acceptor , fermi gas , electron , analytical chemistry (journal) , atomic physics , chemistry , optoelectronics , physics , transistor , optics , quantum mechanics , voltage , chromatography
AbstractThe effect of the silicon-atom distribution profile in donor δ-layers of AlGaAs/InGaAs/AlGaAs heterostructures with donor–acceptor doping on the mobility of the two-dimensional electron gas is studied. The parameters of the δ-layer profiles are determined using the normal approximation of the spatial distributions of silicon atoms, measured by secondary-ion mass spectroscopy. It is shown that the standard deviation σ of the δ-layer profile can be reduced from 3.4 to 2.5 nm by the proper selection of growth conditions. Measurements of the magnetic-field dependences of the Hall effect and conductivity show that such a decrease in σ allowed an increase in the mobility of the two-dimensional electron gas in heterostructures by 4000 cm^2/(V s) at 77 K and 600 cm^2/(V s) at 300 K. The mobility calculation taking into account filling of the first two size-quantization subbands shows that an increase in the mobility is well explained by a reduction in the Coulomb scattering at ionized donors due to an increase in the effective thickness of the spacer layer with decreasing σ of the δ-layer profile.