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Need help modelling the behaviour of semiconductors... (1 Viewer)

m_wahwah

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I have an assignment where I need to:

Perform an investigation to model the behaviour of semiconductors, including the creation of a hole or positive charge on the atom that has lost the electron and the movement of electrons and holes in opposite directions when an electric field is applied across the semiconductor​

I honestly have hardly any idea what I can do to model the experiment. I've searched online and the only examples I can find include using students moving around in a circle with an extra chair, but that's not practical with my class for a number of reasons, and the other one I found involved using eggs, but someone else in the class is using that idea and my teacher's told me to do something else.

Any help, guys? I've been thinking of trying to get, say, 5 tennis balls, or ping pong balls, and get a sort of circular platform with 6 'dents', where everytime I push the one of the balls on the edge, it would push the rest of the balls in front of it so they all move along one position on the platform. Does that make any sense? lol. I have no idea what kind of 'platform' I can use, though, so any help would be appreciated.
 

Drsoccerball

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I have an assignment where I need to:

Perform an investigation to model the behaviour of semiconductors, including the creation of a hole or positive charge on the atom that has lost the electron and the movement of electrons and holes in opposite directions when an electric field is applied across the semiconductor​

I honestly have hardly any idea what I can do to model the experiment. I've searched online and the only examples I can find include using students moving around in a circle with an extra chair, but that's not practical with my class for a number of reasons, and the other one I found involved using eggs, but someone else in the class is using that idea and my teacher's told me to do something else.

Any help, guys? I've been thinking of trying to get, say, 5 tennis balls, or ping pong balls, and get a sort of circular platform with 6 'dents', where everytime I push the one of the balls on the edge, it would push the rest of the balls in front of it so they all move along one position on the platform. Does that make any sense? lol. I have no idea what kind of 'platform' I can use, though, so any help would be appreciated.
Practical : An examination or lesson in which theories and procedures learned are applied to the actual making or doing of something.
What we did was have two nuclei (AKA students ) approach the negative charge (another person) This then through the electron in the air and became a hole while the particle behind it picked it up filling the next hole.
 

m_wahwah

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Practical : An examination or lesson in which theories and procedures learned are applied to the actual making or doing of something.
What we did was have two nuclei (AKA students ) approach the negative charge (another person) This then through the electron in the air and became a hole while the particle behind it picked it up filling the next hole.
I would rather do something that doesn't involve having to use other students as props, tbh
 

keepLooking

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My teacher used an egg carton with a few empty gaps, closed it and shook it. (p-type)
 

Kaido

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Use a material with dents and marbles of similar size. You can create the dents easily if you consider using some plastic materials
 

DatAtarLyfe

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Did someone say semiconductor, pls teach, i said silicon was an insulator in my Chem finals.
If your asking why silicon is a semiconductor and not an insulator, it's because silicon is a semi-metal and thus displays characteristics of both metals and non-metals, conductivity included. They don't conduct like metals yet they don't insulate like non-metals, they kind of lay somewhere in between. If you think of conductors, insulators and semiconductors in ascending order of conductivity, then it would go insulators, semiconductors, conductors. However, if you think of it in ascending order of insulation, then it would be conductors, semiconductors, insulators. SO, semiconductors conduct>insulators but they insulate>conductors, thus why they aren't insulators.

If your talking about something else completely then I have no idea....

P.S tell me if this makes sense
 

Crisium

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If your asking why silicon is a semiconductor and not an insulator, it's because silicon is a semi-metal and thus displays characteristics of both metals and non-metals, conductivity included. They don't conduct like metals yet they don't insulate like non-metals, they kind of lay somewhere in between. If you think of conductors, insulators and semiconductors in ascending order of conductivity, then it would go insulators, semiconductors, conductors. However, if you think of it in ascending order of insulation, then it would be conductors, semiconductors, insulators. SO, semiconductors conduct>insulators but they insulate>conductors, thus why they aren't insulators.

If your talking about something else completely then I have no idea....

P.S tell me if this makes sense
You're still in year 11 ...

In year 12 physics we refer to conductors and insulators with reference to:

"The Forbidden Energy Gap"

"Valence Bands"

"Conduction Bands"

"Free Electrons Leaving Behind Positive Holes"

etc etc
 

Librah

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If your asking why silicon is a semiconductor and not an insulator, it's because silicon is a semi-metal and thus displays characteristics of both metals and non-metals, conductivity included. They don't conduct like metals yet they don't insulate like non-metals, they kind of lay somewhere in between. If you think of conductors, insulators and semiconductors in ascending order of conductivity, then it would go insulators, semiconductors, conductors. However, if you think of it in ascending order of insulation, then it would be conductors, semiconductors, insulators. SO, semiconductors conduct>insulators but they insulate>conductors, thus why they aren't insulators.

If your talking about something else completely then I have no idea....

P.S tell me if this makes sense
The question gave you the band gap as 1.1eV at 0K and 1.3eV at 300K, it asks you to deduce whether silicon was a conductor, insulator or semi-conductor. I mistook 0K for 0 degrees celsius. gg
 

anomalousdecay

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You can model semi conductors as two sections, one filled entirely with marbles and another completely empty, with a solid wall dividing the sections, then have maybe 3 small holes that are only just large enough for one marble at a time to fit through. In each section, you can have another wall which acts as a depletion zone. For the depletion zone, you can also have a few holes in the wall for this as well.

Note the yellow things are electrons and they should all be of equal size (I just did this really quickly to illustrate my point).




I can't exactly remember the model, but I think the Get Smart Physics textbook had a model explained if you can borrow it from somewhere or have a flick through it.
 

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