Concept:The reverse saturation current \( I_0 \) is driven by thermally generated minority carriers and increases exponentially with temperature.
Formula:$$I_0(T_2) = I_0(T_1) \times 2^{\frac{T_2 - T_1}{10}}$$
Solution:- Thermal generation of electron-hole pairs across the bandgap increases rapidly with temperature.
- For both silicon and germanium diodes, \( I_0 \) approximately doubles for every \( 10^\circ\text{C} \) increase in junction temperature (a \( \approx 7\% \) increase per \( ^\circ\text{C} \)).
Why other options are incorrect:- Option B: \( I_0 \) increases with temperature; it does not decrease.
- Option C: \( 2\text{ mV} \) refers to the decrease in barrier potential per degree Celsius (\( \frac{dV_B}{dT} \approx -2\text{ mV/}^\circ\text{C} \)), not the leakage current.
- Option D: Reverse saturation current is strongly temperature-dependent.
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