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At 27°C, germanium has an intrinsic conductivity of 2.13 mho m−1. If the electron and hole mobilities are 0.38 m2V−1s−1 and 0.18 m2V−1s−1, respectively, what is the charge-carrier concentration?
- 2.37 × 10¹⁹ m−3
- 3.28 × 10¹⁹ m−3
- 7.83 × 10¹⁹ m−3
- 8.47 × 10¹⁹ m−3
Correct answer: 2.37 × 10¹⁹ m−3
Solution
The intrinsic conductivity of a semiconductor is determined by the product of the charge-carrier concentration and their mobilities. By using the given mobilities of electrons and holes along with the intrinsic conductivity, we can calculate the charge-carrier concentration, which confirms that option A is correct.
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