PROPHET Execution Path (Device Modeling)

The following describes the major elements in PROPHET execution for electronic device simulation. All file paths are specified relative to the main PROPHET directory. Functions referred to below can be found by searching the TAGS file in the PROPHET root directory.

Main/main.c : main():

parse command line
set up the run environment
read database file: global_dbinit() -> gdbinit() -$gt; do_ndbparse() -$gt; ndbparse()
Read source file: for example, do_batch() -$gt; do_source() -$gt; process()

Main/do_source.c : process():

global_prepass1(): add user input to database
pcd_input_fd: read PROPHET defaults from database?
PASS 1: Verification - check user input for validity
PASS 2: Execution - [For each "card" of user input (system, grid, bias, ...), run the associated module's function]
remove user input from internal database

Mod/Bias/biascmd.c : biascmd():

initial simulation:

make_diff_list(): Used for diffusion simulations

init_bias_table(): Make list of electrical contacts to device

install_zero_bias(): Set all applied biases to zero

initial_psi(): Initialize potential field (psi) to charge neutral value

later simulations:

bias_list(): Determine bias to be applied, bias increment, and number of bias steps

install_bias(): Apply biases to electrode(s)

Solve system for either:

Steady-state: steady_solve()

Transient: steptime()

PDE/Casmbly/steps.c : steady_solve():

solcontrol(): Set up globalsolstruc (description of system)
diff_setup(): set up extra stuff?
outerGS(): set up and do matrix computation to solve PDE system

PDE/Casmbly/loops.c : outerGS():

innerNewton(): Iterative solution of non-linear system

PDE/Casmbly/loops.c : innerNewton(): Most of the matrix work done here

assemble():
accumulate_bc():
clear_dbc()
c2bls(): Matrix solve routine
update_vars():

PDE/Casmbly/c2bls.F (or petsc2.F or petsc2.c):

Here PROPHET calls PETSc 1.2 (or PETSc 2.0) to do the actual matrix computations. PETSc can be compiled for parallel (MPI) computation