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

The electrical conductivity of pure germanium can be enhanced by

Options

Adecreasing the temperature
Bdoping with donor impurities
Cdoping with acceptor impurities
Dincreasing the temperature

Correct answer

D. increasing the temperature

Step-by-step solution

Pure germanium is an intrinsic semiconductor. As temperature increases, thermal energy breaks covalent bonds, generating more electron-hole pairs. This increases the charge carrier density and enhances the electrical conductivity. Doping pure germanium with donor impurities (pentavalent elements) provides free electrons, making it an n-type semiconductor and increasing its conductivity. Doping with acceptor impurities (trivalent elements) creates holes, making it a p-type semiconductor and also increasing its condu

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