1. ECE 874: Physical Electronics
Prof. Virginia Ayres
Electrical & Computer Engineering
Michigan State University

2. Lecture 22, 13 Nov 12
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4. - Approximation/limits on f(E): Use the “hot” limit in ECE 874.
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5. Let’s deal with it.
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6. Deal with E – EF versus E – EC:
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9. Always do the easy one first:
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11. Done! This part is sometimes called NC:
the effective density of states at the conduction band edge E = EC.
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12. Some commonly used gamma functions:
Reference:
Some commonly used gamma functions:
n is always a positive whole number
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13. Would get a similar result for holes:
This part is sometimes called NV:
the effective density of states at the valence band edge E = EV.
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20. With these expressions for n and p, can get several familiar results:
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21. Familiar results: for EF =Ei:
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22. Familiar results: doped n and p in terms of intrinsic ni and Ei:
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