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Concepts Of Physics MCQ Edition [Volume 2]PhysicsSemiconductors and Semiconductor Devices

When a semiconducting material is doped with an impurity, new acceptor levels are generated. During a specific thermal collision, a valence electron gains an energy equal to 2kT , just reaching one of the acceptor levels. Assuming the initial energy of the electron was at the top edge of the valence band and the temperature T is 300 K , determine the energy of the acceptor levels above the valence band.

Options

  1. A103.4 meV
  2. B51.7 meV
  3. C25.8 meV
  4. D50.0 meV

Correct answer

B. 51.7 meV

Step-by-step solution

The energy required for the electron to reach the acceptor level from the top of the valence band is given as E = 2kT . Substituting the value of the Boltzmann constant k = 8.62 10⁻⁵ eV/K and temperature T = 300 K : E = 2 8.62 10⁻⁵ 300 E = 51.72 10⁻³ eV E 51.7 meV

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