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

Upon doping an intrinsic semiconductor with an impurity, its conductivity

Options

  1. Abecomes zero
  2. Bincreases
  3. Cremains the same
  4. Ddecreases

Correct answer

B. increases

Step-by-step solution

The conductivity of a semiconductor is given by = e(n_e _e + n_h _h) , where n_e and n_h are the number densities of electrons and holes respectively. When an intrinsic semiconductor is doped with an impurity (either trivalent or pentavalent), the number of majority charge carriers (either holes or electrons) increases drastically. This increase in the concentration of charge carriers results in a significant increase in the electrical conductivity of the semiconductor. Thus, upon doping an intrinsic semiconductor

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