Question

Assertion (A) : The resistance of an intrinsic semiconductor decreases with increase in its temperature. Reason (R) : The number of conduction electrons as well as hole increase in an intrinsic semiconductor with rise in its temperature.

How does the conductivity of an intrinsic semiconductor vary with temperature ? Explain. Show the variation in a plot.

A pure Si crystal having 5 × 10²⁸ atoms m⁻³ is doped with 1 ppm concentration of antimony. If the concentration of holes in the doped crystal is found to be 4.5 × 10⁹ m⁻³, the concentration (in m⁻³) of intrinsic charge carriers in Si crystal is about

Distinguish between intrinsic and extrinsic semiconductors. Although in an extrinsic semiconductor nₑ ≠ nₕ, yet it is electrically neutral. Why ?