Concept:Free electrons move through unoccupied states in the conduction band with lower effective mass, whereas holes move via sequential electron transfers between localized covalent bonds in the valence band, resulting in higher electron mobility.
Formula:$$\frac{\mu_n}{\mu_p} \approx \frac{1350\text{ cm}^2/\text{V}\cdot\text{s}}{480\text{ cm}^2/\text{V}\cdot\text{s}} \approx 2.8$$
Solution:- In Silicon, \( \mu_n \approx 1350\text{ cm}^2/\text{V}\cdot\text{s} \) and \( \mu_p \approx 480\text{ cm}^2/\text{V}\cdot\text{s} \).
- Electron mobility is approximately \( 2.8 \) times higher than hole mobility.
Why other options are incorrect:- Option A: Electron mobility is higher than hole mobility, not the other way around.
- Option B: The mobilities differ significantly due to differences in effective mass and band structures.
- Option D: Both carriers have finite, well-defined mobilities.
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