Introduction
PADRE simulates the electrical behavior of devices under steady
state, transient conditions or AC small-signal analysis. Multiple
devices can be treated, along with lumped element circuit networks.
PADRE can simulate physical structures of arbitrary geometry--including
heterostructures-with arbitrary doping profiles, which can be obtained
using analytical functions or directly from multidimensional process
simulators such as PROPHET or BICEPS.
For each electrical bias, PADRE solves a coupled set of partial
differential equations (PDEs). A variety of PDE systems are supported
which form a hierarchy of accuracy:
- electrostatic (Poisson equation)
- drift-diffusion (including carrier continuity equations)
- energy balance (including carrier temperature)
- electrothermal (including lattice heating)
A variety of physical mechanisms are supported within these
formulations, including comprehensive representations of
carrier mobility, generation/recombination, and boundary conditions.
PADRE results can be supplemented by the Monte Carlo device
simulator SMC
which is more appropriate for studying hot carrier effects such as
MOS substrate and gate current.
Solutions are represented on a finite element grid within the space
of the device. PADRE supports box discretizations and general
finite element discretizations through non-uniform triangular grids,
which can be refined during the simulation process.
Compared with other device simulation programs, PADRE has a number
of important features:
- Energy balance equations
- Heterostructures
- Enhanced models
- More automatic error-controlled grid generation
- IV predictor-corrector continuation methods
- Modular vector/parallel assembly
- Vector/parallel linear algebra
- Mixed coupled/decoupled nonlinear iterations
More Information
PADRE is accessed using the xtcad command .
PADRE includes a number of utility programs used to process
input/output files:
- bipad
- Converts process simulator output from BICEPS or PROPHET
into a format suitable for PADRE. It also supports simple
manipulations, including truncating, stretching and mirroring of
device profiles. These facilities are useful, for instance, when
converting the process simulator output for a half-MOSFET into a full
MOSFET device for electrical simulation.
- skel
- An interactive program for building the "skeleton" file that
describes the geometry of a device.
- tri
- Takes a "skeleton" and produces the initial triangular mesh used for
the PADRE simulation.
- scat2avs
- Converts a 3D output file (produced using the
plot.3d command
within PADRE) to the format required by the
AVS visualization system.
- pad2a2
- Converts the I-V characteristics in a PADRE logfile
(produced using the log command
within PADRE) to the A2 file format used for parameter
extraction. Only useful for translating MOS device characteristics.
Contacts
- Mark R. Pinto (research!pinto), MH 6E-306
- Michael J. McLennan (mhcnet!mmc), ALC 2C-226