Depending on the application area several different quantity types can be
- Mixed-mode quantities describe a physical quantity for each node of the
simulation circuit. Examples are the node voltage or the node temperature.
- Global device quantities are used within a certain device and describe a
quantity for all segments of this device. Examples are the device temperature
in case of isothermal simulation or the total heat energy.
- Segment quantities are defined on certain segments of a device. Whether
they exist or not depends on the segment material and on the models taken
into account for the current simulation. The impurity concentration, for
example, can only be defined on semiconductors and insulators, the Auger
generation/recombination rate can only be defined when, e.g., electrons and
holes exist for that segment and the Auger-model has been activated.
- Boundary quantities are defined only for boundaries between two segments.
An example is the displacement of the electric field.
The quantity module supports all these types of quantities and manages data
storage, instantiates, modifies, or deletes quantities on demand and controls
access to the information stored in these objects. Thereby it manages
several existing quantity types (see Fig. 3.4) which are
explained in the next section.