Barrier Potential: Explaining the Contradiction

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SUMMARY

The barrier potential equation, Vb = Vt loge(Na*Nd/square(n)), indicates that barrier potential increases with temperature due to the relationship defined by Vt=KT/e. However, the discussion reveals a contradiction where increased temperature generates more minority charge carriers, leading to a decrease in barrier potential by approximately 2 mV per °C. This suggests that the equation does not fully account for the effects of minority carrier concentrations on barrier potential.

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ranju
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The equation for the barrier potential is as follows:

Vb = Vt loge(Na*Nd/square(n)) mV
where Vt=KT/e

This equation shows that the barrier potential is directly proportional to the temperature. So as temperature increases the barrier potential should increase.

But in contradiction to this, I have found the following statement:

" With increase in temperature, more minority charge carriers are produced, leading to their increased drift across the junction. As a result, equilibrium occurs at a lower barrier potential. It is found that the Vb decreases by about 2 mV/0C

Please explain...
 
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There is more than one effect happening here.
Presumably the equation for the barrier potential did not take into account the minority carrier concentrations.
Where are you reading this?
 

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