COMSOL is a very powerful software but is so specific. Also, you system seems to be so simple, I mean in the geometrical aspects at least. I think it would be easier and even more interesting if you could model it using simpler concepts such as impedances in series and parallel. You could increment your model adding distance dependent resistances.

Well, I believe it would be more elegant and maybe easier than COMSOL.

Thank you so much.

Dear Alireza,

welcome,

Adding to the answer of Nicholas,

The structure you presented has three layers, the substrate SrTiO3 which is an insulator with ferroelectric characteristocs, NiO which is a wide gap semiconductor which is normally p type with relatively low resistivity, then finally two gold contacts at he top of the NiO.

You applied an AC voltage between the two electrodes and you say that you want to determine the electric filed penetration in the insulating substrate.

At zero frequency, that a DC voltage the current will path completely in the conductive layer of NiO. As the frequency increases, in addition to the conduction current in the NiO layer, there will be a capacitive current in the substrate shunting the conductive path in NiO. As the frequency increases the capacities current increases while the conductive current remains constant. You can model the device by a conductance G in parallel with the substrate capacitance C. The current I= V Y, the admittance Y= G+j wC,

C represents the electric field penetration in the the substrate.

The electric field theoretically speaking will penetrate through the whole substrate since the material is dielectric.

Therefore i could not see what is the objectives of your simulation?

Field effect on different types of materials is well known.

Try to find a sense for your experiment?

Best wishes