Guilin Sun
Ansys Employee

I am not sure what does the tunneling holes mean here. However CHARGE can simulate tunneling effect in the "Recombination" tab, including band-to-band tunneling. Here is an example

more information for semiconductor:

However, both metal and insulator do not involve in meshing and simulation as metal is considered to be perfect and its shape almost does not effect the results. Insulator does not support charge therefore it is not meshed, except at the interface of the semicodutors where the surface loss can be set.