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GaAs structure with a geometrical constriction
Posted Jun 11, 2014, 5:35 a.m. EDT Version 4.4 1 Reply
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Dear Sirs,
I’m a student at the joint lab CNR-University of Salento in Lecce. I am trying to use an evaluation version of Comsol 4.4 with the Semiconductor Module to understand if it can be useful to simulate the electron transport in a AlGaAs/GaAs device with a two dimensional electron gas at the interface, although for the moment I am just considering a GaAs structure with a geometrical constriction. I was able to implement a model which show me the main voltage drop on the constriction as I expect. However in my final model, I would need to consider also the potential effect suffered by electronic distribution. In my situation, physics suggests us that electron collision is governed by principle of conservation of energy : Ef= 1/2 mv^2+ V. Evidently electron mobility is a circular variable. It is possible to afford this problem with Comsol ?
I had tried to solve it through the following procedure :
1) I have introduced a new variable p onto which the potential is mapped;
2) I have used a weak contribution and auxiliary dependent variable to map the computed electric potential to the new variable p;
3) Finally I defined electronic mobility as (global) function of this new variable p.
What do you think about my argument ?
Nevertheless, while I was defining the global function ((2/m)*(Ef-q*p))^0.5)/(((Vx)^2+(Vy)^2)^0.5) (I’m in 2D) I noted that electronic mobility depends not only on variable p but also on its spatial derivative.
Is this a problem for comsol ?
I will look forward to receive your feedback,
Meanwhile I thank you in advace,
Best regards,
Luciano
I’m a student at the joint lab CNR-University of Salento in Lecce. I am trying to use an evaluation version of Comsol 4.4 with the Semiconductor Module to understand if it can be useful to simulate the electron transport in a AlGaAs/GaAs device with a two dimensional electron gas at the interface, although for the moment I am just considering a GaAs structure with a geometrical constriction. I was able to implement a model which show me the main voltage drop on the constriction as I expect. However in my final model, I would need to consider also the potential effect suffered by electronic distribution. In my situation, physics suggests us that electron collision is governed by principle of conservation of energy : Ef= 1/2 mv^2+ V. Evidently electron mobility is a circular variable. It is possible to afford this problem with Comsol ?
I had tried to solve it through the following procedure :
1) I have introduced a new variable p onto which the potential is mapped;
2) I have used a weak contribution and auxiliary dependent variable to map the computed electric potential to the new variable p;
3) Finally I defined electronic mobility as (global) function of this new variable p.
What do you think about my argument ?
Nevertheless, while I was defining the global function ((2/m)*(Ef-q*p))^0.5)/(((Vx)^2+(Vy)^2)^0.5) (I’m in 2D) I noted that electronic mobility depends not only on variable p but also on its spatial derivative.
Is this a problem for comsol ?
I will look forward to receive your feedback,
Meanwhile I thank you in advace,
Best regards,
Luciano
1 Reply Last Post Jun 11, 2014, 5:43 a.m. EDT
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Posted:
1 decade ago
Dear Luciano,
during the activation period of the Comsol trial versions is also active technical support, I think the best thing is to write support@comsol.com, your request will be referred to a specialist who will reply as soon as possible. Have a nice day,
Daniela
during the activation period of the Comsol trial versions is also active technical support, I think the best thing is to write support@comsol.com, your request will be referred to a specialist who will reply as soon as possible. Have a nice day,
Daniela