3.4.1.1 Quantity Types

Minimos-NT manages more than hundred different types of quantities like the electrostatic potential, the contact potential, the contact current, currents of electrons and holes to mention only few of them. For each type an entry describing its properties is stored in a table. This information includes

• the quantity identifier which identifies a certain type of quantity.
• the quantity class identifier combines all quantity types which differ only by the carrier type like electrons or holes. This enables, e.g, the iteration over all carriers or all carrier temperatures which is needed for certain models.
• a short name and a textual description of the quantity type for output and debugging purposes.
• the type of the carrier in case of carrier depending quantities.
• the information to define the type within the PIF-Libraries if they are used for input and output.
• the unit class which is used to specify the typical unit and the internal unit of the quantity. Quantities read in from the input libraries are scaled to internal units specified by the unit class during the initialization phase. When the quantities are written to output files the values are scaled back.
• a call-back function returning the grid type on which the quantity is defined. Grid types are simply none for global quantities, segment for segment quantities and boundary for boundary quantities. This allows to switch the grid on and off depending on several internal states. For instance, quantities of type lattice temperature defined on segments which are thermal contacts must not use a grid since several models expect a constant global quantity. For non-thermal segments the lattice temperature is defined on a grid.
• some flags which describe if the quantity is used for transient, hydrodynamic, six-moments, or mixed-mode simulations only.
• a flag to identify vector and array quantities.
• a flag which tells if the quantity describes a carrier type.
• a call-back function used to determine whether a quantity is a solution quantity or not. It is used during the equation assembly step.

When a quantity has to be instantiated, this description is used to determine the properties of the quantity and to ensure correct initialization.