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bhuvanesh

Aug 29, 2013
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question : find intrinsic carrier concentration at T=200k for silicon (in cm^-3).
Answer is attached.In that why is that (200/300)^3 is added there.my only hope is this forum.Thank you
 

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Arouse1973

Adam
Dec 18, 2013
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question : find intrinsic carrier concentration at T=200k for silicon (in cm^-3).
Answer is attached.In that why is that (200/300)^3 is added there.my only hope is this forum.Thank you

Are you seriously trying to teach yourself semiconductor physics?
Adam
 

Ratch

Mar 10, 2013
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question : find intrinsic carrier concentration at T=200k for silicon (in cm^-3).
Answer is attached.In that why is that (200/300)^3 is added there.my only hope is this forum.Thank you

Nc and Nv have temperature parameters that are raised to the 3/2 power. If the temperature ratios are moved outside the exponent brackets, then the temperature ratios have to be raised to the third power to compensate for the move.

Ratch
 

bhuvanesh

Aug 29, 2013
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Nc and Nv have temperature parameters that are raised to the 3/2 power. If the temperature ratios are moved outside the exponent brackets, then the temperature ratios have to be raised to the third power to compensate for the move.

Why we need to move temperature outside the exponential.i have solved this in my way say weather it is right or wrong with explanation .Thank you
 

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Ratch

Mar 10, 2013
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Why we need to move temperature outside the exponential.i have solved this in my way say weather it is right or wrong with explanation .Thank you

Nv and Nc have their temperature parameters inside a term raised to the 3/2 power. You don't need to take those temperatures outside the radical, but if you do, you have to compensate for their removal. The solution seems to have elected to move the temperature parameter to the outside the radical. Therefore, the temperature term has to be raised to the third power to compensate for the movement.

Ratch
 

bhuvanesh

Aug 29, 2013
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sire i dont understand what do you saying here ,where it is raised to 3/2.its raised to power 3.
 

Ratch

Mar 10, 2013
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sire i dont understand what do you saying here ,where it is raised to 3/2.its raised to power 3.

What book are you using? Doesn't it have the formula shown in the attachment? When Nv and Nc are multiplied together, the "2" in the denominator is cancelled and "3" remains.

RatchIMG_1128.JPG
 
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