G.P.Kovtun, A.I.Kondrik, A.A.Yatsenko
Received June 10, 1999
An improved multilevel model has been proposed for forecasting
of property modifications in direct gap semiconductors, namely, the
mobility, resistivity, and Fermi level position depending on concentration
of multicharge donors and acceptors, amphoteric impurities of DA,
DDA, and DAA types, their energy positions in the semiconductor band
gap, structure and doping non-uniformity (accumulations of defects
and impurity clusters) within a wide temperature range. An aplication
program has been developed basing on the model. Physical properties
of gallium arsenide have been simulated numerically, the five-level
model has been compared to the improved one and the latter has been
shown to offer some advantages. The influence of an EL-2 defect after
an irradiation followed by a heat treatment on the main electrophysical
parameters of gallium arsenide has been studied in a wide temperature
range. The mobility variation within the 300<T<1100 temperature
range has been considered theoretically as a function of EL-2 defects
and clusters concentrations. The mechanisms of the defect influence
on the mobility and resistivity are discussed.