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Next: 3.5.3 The Network-Model's Description Up: 3.5 The Network-Model Previous: 3.5.1 Model Reuse


3.5.2 Default Overloading

Since many TCAD applications require several similar variants of models, the possibility to overload a port's default setting is desirable. Let us assume that the gate length of a device that is produced by a simulation-flow-model is adjustable via one of its input ports. This simulation-flow-model could then be used multiply in a network-model, as depicted in Figure 3.5, using different values for the gate length by means of default overloading.
\begin{Figure} % latex2html id marker 2447\centering \includegraphics{fig/mode... ...0.18$, $0.25$, and $0.50$\ for the port named \textit{gate-length}.}\end{Figure}

As a result the model is only defined once but there exist several similar instances of itself in the simulation. Given that an investigation requires more than one instance of this simulation-flow-model, all of these models share common properties except the gate length. Therefore, if a change of the simulation-flow-model is necessary, this change has only to be done once at the definition of the simulation-flow-model. Typical TCAD investigations require up to ten snapshots of a process (including several wafer areas under various process conditions). This illustrates how useful model reuse is in conjunction with parameter overloading, and the drastic decrease of administrative efforts which are required to maintain simulation descriptions.

next up previous contents
Next: 3.5.3 The Network-Model's Description Up: 3.5 The Network-Model Previous: 3.5.1 Model Reuse
Rudi Strasser
1999-05-27