Module 6 : PHYSICS OF SEMICONDUCTOR DEVICES
Lecture 34 : p- type Semiconductors
Example 8
  In an n-type semiconductor 25% of the donor atoms are ionized at 300 K. Determine the location of the Fermi level with respect to the donor level.
  Solution
  As 25% of donor atoms are ionized, the occupation probability of donor level is 0.75. Thus
 
$\displaystyle F(E_D) = \frac{1}{1+ \exp(\frac{E_D-E_F}{kT})}= 0.75$
  Solving, $ E_D-E_F= -0.028$ eV.
 

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