A. Carrier Interface Models in

To use a specific interface model at the interface of two semiconductor
segments the appropriate value has to be assigned to the `interfaceDD`
or `interfaceHD` keywords in the `Electron` or `Hole`
subsection of the two segments within the `Phys` section of the input
deck. The interface model is used only if the values of these keywords are the
same for both segments. The `"CQFL"` model is the default model and is
also used in case the specified values are not equal.

The following example shows how to specify the TFE model for electrons at the
interface between the segments named `Channel` and `UpperBarrier`
for drift-diffusion and hydrodynamic simulations. For the drift-diffusion
interface model the effective tunnel length is modified from its default value
to
5 nm.

Phys { ... +Channel { Electron { interfaceDD = "TFE"; interfaceHD = "TFE"; InterfaceDD { TFE { d = 5e-9 m; } } } } +UpperBarrier { Electron { interfaceDD = "TFE"; interfaceHD = "TFE"; InterfaceDD { TFE { d = 5e-9 m; } } } } ... }

In the following *J* denotes the current density, *S* the energy flux density,
and
*E*_{} the difference of band edges. The carrier concentration is denoted
by .

The following three carrier interface models are implemented in *MINIMOS-NT*:

- continuous quasi
*Fermi*level model*J*_{2}= *J*_{1}(A1) = ^{ . }^{ . }exp -(A2) *S*_{2}= *S*_{1}-^{ . }*E*_{}^{ . }*J*_{2}(A3) *T*_{2}= *T*_{1}(A4)

- thermionic emission model
*J*_{2}= *J*_{1}(A5) *J*_{2}= q ^{ . }*v*_{2}^{ . }-^{ . }*v*_{1}^{ . }^{ . }exp -(A6) *S*_{2}= *S*_{1}-^{ . }*E*_{}^{ . }*J*_{2}(A7) *S*_{2}= - k _{B}^{ . }*T*_{2}^{ . }*v*_{2}^{ . }-^{ . }k_{B}^{ . }*T*_{1}^{ . }*v*_{1}^{ . }^{ . }exp -(A8)

with the thermionic emission velocity

- thermionic field emission model
*J*_{2}= *J*_{1}(A10) *J*_{2}= q ^{ . }*v*_{2}^{ . }-^{ . }*v*_{1}^{ . }^{ . }exp -(A11) *S*_{2}= *S*_{1}-^{ . }*E*_{}-*E*_{}^{ . }*J*_{2}(A12) *S*_{2}= - k _{B}^{ . }*T*_{2}^{ . }*v*_{2}^{ . }-^{ . }k_{B}^{ . }*T*_{1}^{ . }*v*_{1}^{ . }^{ . }exp -(A13)

with the thermionic emission velocity (A.9) and the barrier hight lowering

*E*_{}=(A14)

For

*E*_{}= 0 the TFE model reduces to the TE model.

1999-05-31