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Amorphous Silicon under electron impact: in-bulk electron-hole pair formation, and secondary electron emission (SEE)

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Hello all!

Here is what I want to simulate, first in 2D. A 500 keV electron (let's say coming from the right) hits an amorphous silicon surface, creating many electron-hole pair inside the amorphous silicon. Some of these electrons are ejected back outside the amorphous silicon. The whole system is put inside a constant homogeneous top-down electric field to separate the electron-hole pair.

I just want to start right. My question is: which physics & coupling should I use for better results? Here is what I wanted to try next week:
-> For the single primary electron: charged particle tracing (cpt) (and the trajectory will be a little bent because of the coupling with the electric field),
-> For the constant electric field: electrostatics (es),
-> For the electron-hole pair behavior inside the amorphous silicon: plasma (plas) (although it's not plasma, coupled with the electric field, like in the dielectric barrier discharge tuto example),
-> But what should I use to provoke an e-/h+ pair creation when my incoming electron hits the amorphous silicon?
-> For the secondary electrons exciting the silicon: nothing, as they are the product of the previous coupling.
Would all that be a good start?

Another quick question: amorphous silicon is not included in my material list. I can define it, but is there a quicker way to import this material?

Thank you very much.


2 Replies Last Post Sep 6, 2018, 5:45 a.m. EDT

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Posted: 6 years ago Sep 3, 2018, 10:08 a.m. EDT

Hello!

Just for an update. I started with Charged Particles Trajectories (cpt), input the secondary electrons emission upon the "frozen-at-boundary" primary electron. The electron-hole pair behavior can be well described thanks to the "Semiconductors" physics.

However, I can't find the e-/h+ pair creation upon incoming electron on silicon. Someone would have any idea? Has someone already modeled this kind of interaction?

Thank you for your answer.

Hello! Just for an update. I started with *Charged Particles Trajectories (cpt)*, input the secondary electrons emission upon the "frozen-at-boundary" primary electron. The electron-hole pair behavior can be well described thanks to the "Semiconductors" physics. However, I can't find the e-/h+ pair creation upon incoming electron on silicon. Someone would have any idea? Has someone already modeled this kind of interaction? Thank you for your answer.

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Posted: 6 years ago Sep 6, 2018, 5:45 a.m. EDT

Hello there!

I tried reposting. Please follow the other thread here and consider this one void.

Hello there! I tried reposting. Please follow the other thread [here](https://www.comsol.com/forum/thread/206641/electron-beam-induced-current-in-silicon) and consider this one void.

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