Zaymiey

⚛️ Physics  ·  Semiconductor Electronics  ·  NEET & JEE

The Einstein relation between mobility and diffusion coefficient is:

Answer: D = mu × kT/e.

  • A D = mu × kT/e
  • B D = mu × e/kT
  • C D = mu × kT
  • D D/mu = e

Correct answer: A. D = mu × kT/e

Explanation: Einstein relation: D/mu = kT/q = V<sub>T</sub> (thermal voltage). Fundamental relationship valid in equilibrium.

Conductorconduction bandvalence bandbands overlapSemiconductorconduction bandvalence bandsmall gap (~1 eV)Insulatorconduction bandvalence bandlarge gap(> 3 eV)

Conductors have overlapping bands, semiconductors have a small energy gap that can be bridged by heat or doping, and insulators have a large gap that blocks conduction.

Concept context

Band theory, p-n junction, diodes, transistors, logic gates, and integrated circuits.

Read the full Semiconductor Electronics notes →