Fundamentals of Physics, Volume 1, Chapter 1-20
10th Edition
ISBN: 9781118233764
Author: David Halliday
Publisher: WILEY
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Question
Chapter 41, Problem 33P
To determine
To calculate:
(a) the probability that a state at the bottom of the
(b) the probability that a state at the top of the valence band in germanium is not occupied.
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The occupancy probability function can be applied to semiconductors as well as to metals. In semiconductors the Fermi energy is close to the midpoint of the gap between the valence band and the conduction band. For germanium, the gap width is 0.67 eV. What is the probability that (a) a state at the bottom of the conduction band is occupied and (b) a state at the top of the valence band is not occupied? Assume that T = 290 K. (Note: In a pure semiconductor, the Fermi energy lies symmetrically between the population of conduction electrons and the population of holes and thus is at the center of the gap.There need not be an available state at the location of the Fermi energy.)
Which statement about the intrinsic carrier concentration in a semiconductor material is FALSE?
The intrinsic carrier concentration is exponentially dependent on the inverse of the temperature of the semiconductor material.
In an intrinsic semiconductor material, the concentration of electrons in the conduction band is equal to the concentration holes in the valence band.
The intrinsic carrier concentration of a semiconductor material at a constant temperature depends on the Fermi energy.
The intrinsic Fermi energy is positioned near the center of the bandgap for an intrinsic semiconductor.
The electron number density in a semiconductor varies from 1020 m³ to 10¹2 m³ linearly over a
distance of 4 µm. Determine the electron diffusion current and electric field at the midpoint if
no current flows, He = 0.135 m²V-¹s¹ and T = 300 K.
Chapter 41 Solutions
Fundamentals of Physics, Volume 1, Chapter 1-20
Ch. 41 - Prob. 1QCh. 41 - Prob. 2QCh. 41 - Prob. 3QCh. 41 - Prob. 4QCh. 41 - Prob. 5QCh. 41 - Prob. 6QCh. 41 - Prob. 7QCh. 41 - Prob. 8QCh. 41 - Prob. 9QCh. 41 - Prob. 10Q
Ch. 41 - Prob. 11QCh. 41 - Prob. 1PCh. 41 - Prob. 2PCh. 41 - Prob. 3PCh. 41 - Prob. 4PCh. 41 - Prob. 5PCh. 41 - Prob. 6PCh. 41 - Prob. 7PCh. 41 - Prob. 8PCh. 41 - Prob. 9PCh. 41 - Prob. 10PCh. 41 - Prob. 11PCh. 41 - Prob. 12PCh. 41 - Prob. 13PCh. 41 - Prob. 14PCh. 41 - Prob. 15PCh. 41 - Prob. 16PCh. 41 - Prob. 17PCh. 41 - Prob. 18PCh. 41 - Prob. 19PCh. 41 - Prob. 20PCh. 41 - Prob. 21PCh. 41 - Prob. 22PCh. 41 - Prob. 23PCh. 41 - Prob. 24PCh. 41 - Prob. 25PCh. 41 - Prob. 26PCh. 41 - Prob. 27PCh. 41 - Prob. 28PCh. 41 - Prob. 29PCh. 41 - Prob. 30PCh. 41 - Prob. 31PCh. 41 - Prob. 32PCh. 41 - Prob. 33PCh. 41 - Prob. 34PCh. 41 - Prob. 35PCh. 41 - Prob. 36PCh. 41 - Prob. 37PCh. 41 - Prob. 38PCh. 41 - Prob. 39PCh. 41 - Prob. 40PCh. 41 - Prob. 41PCh. 41 - Prob. 42PCh. 41 - Prob. 43PCh. 41 - Prob. 44PCh. 41 - Prob. 45PCh. 41 - Prob. 46PCh. 41 - Prob. 47PCh. 41 - Prob. 48PCh. 41 - Prob. 49PCh. 41 - Prob. 50PCh. 41 - Prob. 51PCh. 41 - Prob. 52PCh. 41 - Prob. 53P
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