Concept:Increased temperature generates more intrinsic electron-hole pairs, reducing the bandgap energy and lowering the contact barrier potential.
Formula:$$\frac{dV_B}{dT} \approx -2\text{ mV/}^\circ\text{C} \quad (\text{or } -2.5\text{ mV/K})$$
Solution:- As temperature increases, additional thermal energy elevates valence electrons into the conduction band.
- This reduces the energy required for charge carriers to cross the depletion region, lowering the barrier potential at a rate of roughly \( 2\text{ mV} \) per \( ^\circ\text{C} \) increase.
Why other options are incorrect:- Option A: The temperature coefficient of the forward barrier potential is negative, not positive.
- Option B: \( V_B \) is temperature dependent.
- Option D: Reverse saturation leakage current (\( I_0 \)) roughly doubles every \( 10^\circ\text{C} \), not the barrier potential.
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