Concept:Because intrinsic thermal generation produces very few minority carriers at room temperature (especially in silicon, which has a relatively large bandgap \(E_g = 1.12\text{ eV}\)), the reverse saturation leakage current is extremely small—typically in the nano-ampere (\(\text{nA}\)) to micro-ampere (\(\mu\text{A}\)) range.
Formula:$$I_{\text{leakage}} = I_s \approx 10^{-9}\text{ A to } 10^{-6}\text{ A}$$
Solution:- In Silicon: Reverse current \(I_s\) is on the order of \(\text{nA}\) (or low \(\mu\text{A}\)).
- In Germanium: Reverse current \(I_s\) is larger, typically on the order of \(\mu\text{A}\).
- Both are orders of magnitude smaller than forward conduction currents (which are in the \(\text{mA}\) to \(\text{A}\) range).
Why other options are incorrect:- Option A: Amperes represent heavy power-level forward currents, not reverse leakage.
- Option B: Milli-amperes represent normal forward current through low-power diodes.
- Option D: Kilo-amperes represent extreme fault currents in utility grids.
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