Engineering Board Exam Reviewer · Engineering Materials · hard
Intrinsic silicon at room temperature has 1 × 1016 electrons/m³ (and the same number of holes), with e = 0.14 and h = 0.05 m2/V· s. What is its electrical conductivity? (e = 1.602 × 10-19 C)
- 2.24 × 10-4 ( · m)-1
- 3.04 × 10-4 ( · m)-1
- 1.44 × 10-4 ( · m)-1
- 6.09 × 10-4 ( · m)-1
Answer
B. 3.04 × 10-4 ( · m)-1
Solution
= n|e|( e + h) = 1016(1.602 × 10-19)(0.19) = 3.04 × 10-4 ( · m)-1.
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