FUNDAMENTALS OF PHYSICS (LLF)+WILEYPLUS
11th Edition
ISBN: 9781119459132
Author: 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.)
The Fermi energy of a doped semiconductor is different from that of a pure semiconductor. Consider silicon, where the energy difference between the top of the valence band and the bottom of the conduction band is 1.11 eV. At a temperature of 300 K the Fermi energy of pure silicon lies approximately between the bottom of the conduction band and the top of the valence band. (a) Calculate the probability of occupying a state at the bottom of the conduction band. Consider now that the silicon has been doped with donor atoms that introduce a state at 0.15 eV below the conduction band background. Doping also caused the Fermi level to be shifted to an energy 0.11 eV below the bottom of the conduction band. (b) Under these conditions, calculate the occupancy of the lower end of the conduction band. (c) Calculate the probability that the level introduced by the donor impurities is occupied. JUSTIFY ALL ANSWERS.
The Fermi energy of a doped semiconductor is different from that of a pure semiconductor. Consider silicon, where the energy difference between the top of the valence band and the bottom of the conduction band is 1.11 eV. At a temperature of 300 K the Fermi energy of pure silicon lies approximately between the bottom of the conduction band and the top of the valence band. (a) Calculate the probability of occupying a state at the bottom of the conduction band. Consider now that the silicon has been doped with donor atoms that introduce a state at 0.15 eV below the conduction band background. Doping also caused the Fermi level to be shifted to an energy 0.11 eV below the bottom of the conduction band. (b) Under these conditions, calculate the occupancy of the lower end of the conduction band. (c) Calculate the probability that the level introduced by the donor impurities is occupied.
Chapter 41 Solutions
FUNDAMENTALS OF PHYSICS (LLF)+WILEYPLUS
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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