Solution Found!
Answer: Pure silicon contains approximately free electrons
Chapter 25, Problem 54E(choose chapter or problem)
Pure silicon contains approximately \(1.0 \times 10^{16}\) free electrons per cubic meter.
(a) Referring to Table 25.1, calculate the mean free time \(\tau\) for silicon at room temperature.
(b) Your answer in part (a) is much greater than the mean free time for copper given in Example 25.11. Why, then, does pure silicon have such a high resistivity compared to copper?
Questions & Answers
QUESTION:
Pure silicon contains approximately \(1.0 \times 10^{16}\) free electrons per cubic meter.
(a) Referring to Table 25.1, calculate the mean free time \(\tau\) for silicon at room temperature.
(b) Your answer in part (a) is much greater than the mean free time for copper given in Example 25.11. Why, then, does pure silicon have such a high resistivity compared to copper?
ANSWER:Solution 54E
Introduction
We have to calculate the mean free time for the electrons in silicon at room temperature. Then we have to discuss why the silicon has higher resistivity.
Step 1
If mean free time is , then we know that
Hence the mean free time for silicon at room temperature is s.