Model of intrinsic semiconductor behaviour

[jclough]

Homework Statement

This isn't a problem as such. This is about a practical I did, to verify the non-classical model of silicon conductivity (which increases with temperature) and then to calculate the band gap energy of silicon.

Homework Equations

This was the main equation of the model we were verifying...
R=Ro*exp(To/T)

where To=Eg/2kB

kB = Boltzmann constant
Eg = band gap energy

Of course this only works in the intrinsic region.

I'm trying to think of other physical interpretations of the data for a certain section of the report and I was wondering if anybody knew where I could find a better model of semiconductor conductivity, perhaps a book or a website. That is, if there is a better model. I don't know if the model is the accepted one, as I haven't been taught about the topic!

Thanks,
Jessica.

 

[snapback]

hello, hope it is not too late for your practical

you could consider following formula for the conductivity [itex] \sigma[/itex]:

[itex] \sigma=q\cdot \mu \cdot n [/itex]

with

• [itex] q: [/itex] electric charge
• [itex] \mu: [/itex] mobility
• [itex] n: [/itex] free carrier concentration

the free carrier concetration depends mainly exponentially on temperature (there are some minor deviations, which are usually neglected). The mobility of carriers usually decreases with increasing temperature in an intrinsic semiconductor , thus the Ro in the equation you have been given, isn't actually constant

I do not know your background, but I think virtually any general book on semiconductor physics or physics of semiconductor devices could help you further. A very nice link is

http://www.tf.uni-kiel.de/matwis/amat/semi_en/index.html"

good luck

 

[thomate1]

The model you used in your experiment is known as the intrinsic semiconductor model, which explains the behavior of semiconductors at their purest form without any impurities or doping. This model shows that the conductivity of a semiconductor increases with temperature, which is contrary to the behavior of metals. This is due to the increase in the number of electrons that are thermally excited from the valence band to the conduction band.

There are other models that describe the behavior of semiconductors, such as the extrinsic semiconductor model that takes into account the effect of impurities on the conductivity. This model is commonly used in practical applications of semiconductors, such as in electronic devices.

If you are interested in learning more about semiconductor models, I would recommend consulting textbooks or online resources on solid state physics or semiconductor physics. These sources will provide you with a more comprehensive understanding of the different models and their applications.

Additionally, you can also consult with your instructor or a more experienced scientist in the field for guidance on selecting the most appropriate model for your experiment and data analysis. It is always important to critically evaluate and compare different models to ensure the accuracy and validity of your results.