How do I calculate the Fermi Energy of a compound?

AI Thread Summary
To calculate the Fermi Energy of pure InAs with a bandgap of 0.33 eV, it is assumed that the Fermi Energy (EF) is at the center of the energy gap, which means EF is 0.165 eV. The number of electrons in the conduction band at 300K can be determined using the equation N_e = N_C e^{\frac{-(E_G - E_F)}{k_B T}}, where N_C is calculated from the given parameters. The equation for N_C involves the effective mass of electrons and temperature, which is crucial for determining the electron concentration. Understanding that the Fermi energy represents the energy of the highest occupied state at absolute zero is essential for applying these concepts correctly. The problem requires substituting values into the equations to find the number of conduction band electrons.
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Homework Statement


1) This question has to do with pure InAs, with a bandgap 0.33 eV, electron mass 0.02, hole mass 0.41.
(a) Evaluate the number of electrons/m3 int he conduction band at 300K. For this purpose you can assume the Fermi Energy is exactly at the center of the energy gap.


Homework Equations



If the Fermi energy EF is located at least kT away from the conduction or valence band edge, the probablility of occupation of the electron state is adequately given by
f(E) = e^{\frac{-(E - E_F )}{k_B T}}

The number of electrons is given below as Ne
<br /> N_e = N_C e^{\frac{-(E_G - E_F )}{k_B T}} \\<br /> N_C = 2(\frac{2\pi m^{*}_{e} k_B T}{h^2})^{3/2}<br />

I believe EG is the band gap energy. h is Planck's Constant.

The Attempt at a Solution



The part where I am stumped is where it says that the "Fermi energy is exactly at the center of the energy gap." Does that mean I take EF to be 0.33 eV / 2? If so, I guess the rest of the problem is just plug and chug.
 
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