Can I remove dielectric layer when calculating molecular junctions-based FET?

[wot19920302]

Dear Quantumwise staffs:
        For field effect transistor configuration in ATK, it can be seen that dielectric layer (in general, SiO₂) need to be added between metallic layer and molecular junctions in tutorials. In tranditional MOSFET, e.g. n-type enhencement MOSFET, dielectric layer is used to avoid the transport of carriers from conductive channel to gate terminal. Can anyone please tell me what the dielectric layer takes effect in molecular junctions? Is it proper (reasonable) to remove the dielectric layer when I construct molecular junctions-based FET?
         Best wishes

[Petr Khomyakov]

Can anyone please tell me what the dielectric layer takes effect in molecular junctions? Is it proper (reasonable) to remove the dielectric layer when I construct molecular junctions-based FET?

I think it is really dependent on what you want to investigate. As a matter of fact, a vacuum padding that you will naturally have  around your molecular junction will serve as a dielectric in any way, just the dielectric constant for such a dielectric spacer is 1. I would guess that for any (if possible) molecular junction-based transistor there will be some dielectric spacer between the metal gate and the channel as for any other FET. Which dielectric to choose would perhaps be the actual topic of research.
 

[wot19920302]

so you think that it's ok to remove the dielectric layer if we just want to add a dieletric layer with relative permittivity ε_r=1？

[Petr Khomyakov]

so you think that it's ok to remove the dielectric layer if we just want to add a dieletric layer with relative permittivity ε_r=1？

It is totally up to you and your research goals.

[wot19920302]

thanks for your kind help!