The two-dimensional device simulator MINIMOS-NT  is an ancestor of the
well-known MOS device simulator MINIMOS 6 . MINIMOS-NT is a generic
simulator accounting for a variety of materials, including group IV
semiconductors, III-V compound semiconductors and their alloys, and non-ideal
dielectrics. A stable base of material parameters for semiconductors of
interest is extracted and used for device modeling issues. MINIMOS-NT is
applicable to devices with high complexity in respect to materials, geometries,
etc. allowing state-of-the-art simulations of MOS devices
, HEMTs [59,60,61], SiGe HBTs , and
III-V HBTs [63,64]. The models are verified against statistically
analyzed measured data.
In MINIMOS-NT the simulation domain is partitioned into independent regions,
so-called segments. This partitioning is done with respect to the material
class, e.g., contacts, insulators, and semiconductors. For these segments
different sets of parameters, models and algorithms can be independently
defined. When the simulation domain is properly split into segments, there are
no abrupt changes of the material parameters within the segments. Abrupt
variations of the material parameters should only occur at the interface of two
Various important physical effects, such as bandgap narrowing,
surface recombination, and self heating, are taken into account. Heat
generated at the heterojunctions cannot completely leave the device, especially
in the case of III-V semiconductor materials. Therefore, significant
self-heating occurs in the device and leads to a change of the electrical
Emphasis was also laid on bandgap narrowing as one of the crucial
heavy-doping effects to be considered for bipolar devices .
A new physically-based analytical bandgap narrowing model was developed,
applicable to compound semiconductors, which accounts for semiconductor
material, dopant species, and lattice temperature. As the minority
carrier mobility is of considerable importance for bipolar transistors, a new
universal low field mobility model has been implemented in MINIMOS-NT
. It is based on Monte-Carlo simulation results and distinguishes
between majority and minority electron mobilities.
Energy transport equations are necessary to account for non-local effects, such
as velocity overshoot [67,68]. A new model for the electron
energy relaxation time has been presented  which is based on
Monte-Carlo simulation results and is applicable to all relevant semiconductors
with diamond and zinc-blende structure. The energy relaxation times are
expressed as functions of the carrier and lattice temperatures and, in the case
of semiconductor alloys, of the material composition.
Considering the nature of the simulated devices (including abrupt SiGe/Si, InGaP/GaAs and AlGaAs/InGaP heterointerfaces) and the high electron temperatures observed at maximum bias sophisticated thermionic-field emission interface models  in conjunction with the hydrodynamic transport model are used. At the other (homogeneous or graded) interfaces continuous quasi-Fermi levels are assumed.