Semiconductor physics

What is the drift velocity of electrons with a mobility of 1000 cm²/V·s in an electric field of 100 V/cm?

  1. A1×10³ cm/s
  2. B1×10⁵ cm/s
  3. C1×10⁷ cm/s
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Answer: B. 1×10⁵ cm/s

Drift velocity is v = μE: 1000 cm²/V·s × 100 V/cm = 1×10⁵ cm/s. At very high fields, however, velocity no longer increases proportionally and levels off at about 1×10⁷ cm/s in silicon (velocity saturation).

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