Physics for Scientists and Engineers
6th Edition
ISBN: 9781429281843
Author: Tipler
Publisher: MAC HIGHER
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Chapter 38, Problem 69P
To determine
Proof that the distribution function of electrons in the
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In a certain semiconductor, the valence band can be approximated by the function E(k) = Eo ak² and the
conduction band can be described by the function E(k)= E₁ + 3k². Here E(k) is the electron energy and k is the
wavevector. Plot E(k) for the two bands. What is the bandgap of this semiconductor? Is this a direct
or indirect bandgap semiconductor?
Assume that a GaAs semiconductor has a lattice
constant a=7.5 Á, and the atoms of Ga and As are
hard spheres.
Assume an electric field of E=1000 V/m is applied
on the GaAs semiconductor at T = 300 K. The drift
%3D
current ?
Silicon is doped with phosphorus atoms (column V of Mendeleev table) with a concentration of
1018 cm-3
a- What is, at 27 °C, the electron density in doped Si. Use this result to derive the hole density.
Which type of semiconductor is obtained?
b- Calculate, at 27 °C, the position of the Fermi level EF and plot the band diagram.
Chapter 38 Solutions
Physics for Scientists and Engineers
Ch. 38 - Prob. 1PCh. 38 - Prob. 2PCh. 38 - Prob. 3PCh. 38 - Prob. 4PCh. 38 - Prob. 5PCh. 38 - Prob. 6PCh. 38 - Prob. 7PCh. 38 - Prob. 8PCh. 38 - Prob. 9PCh. 38 - Prob. 10P
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