Semiconductor process and device simulation typically generates
large amounts of data at each step.
During process simulation, each step produces a
two-dimensional
representation of the semiconductor wafer that includes a boundary
representation of the wafer domain under consideration, material data
for different areas of the wafer, grids for carrying distributed
quantities along boundaries and in the wafer bulk, and the values
of these distributed quantities on their respective grids.
In process simulation, distributed quantities include the
concentrations of total and electrically active dopants,
of silicon interstitials,
of dopant clusters, and the distributions of amorphization, strain,
and stress in the material;
in device simulation,
the distributions of the carrier velocities,
of the current density,
of the electrical potential,
and of the temperature.
During device simulation, electrical quantities - either as lump
values or as distributed values on grids - are generated.
A MINIMOS [SSP80] [FHH
94] simulation of a MOS transistor, e.g.,
calculates voltages and currents for all electrodes, parameters
such as the maximum values of mobility and drift velocity of
electrons and holes, and their respective distributions.
All these data are produced at each operating point and make
for an impressive pile of numbers.
In general, the number and diversity of physical quantities computed during simulation depends only on the sophistication of the models employed. Therefore, no restrictions should be established or enforced with respect to the nature of simulation data handled by a TCAD environment.
For the sheer amount of data generated during simulation, it is not feasible to store tool output data in a database and extract it again when necessary, but it was decided to use a file-based concept to keep data transfer overhead as small as possible.