question on semiconductor device,..

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1. The problem statement, all variables and given/known data

I have a question on semiconductor device,,

A drift current density of Jdrf=150 A/cm2 is required in a semiconductor device using n-type silicon with an applied electric field of E=25V/cm. Determine the imjpurit doping concentration that will achieve this specification.

i don't really understand this topic, can someone help me plz..

the answer is, If Nd = 3.13 * 10power 16 per cmcube,, then impurity doping concentration will be 1200..

i don't know how can i find Nd.. sind n has about the same value as Nd..



2. Relevant equations

Jdif = e(μn)nE

3. The attempt at a solution

(μn)n = 3.75 * 10 power -19


how can i find n or Nd ??

i know that (μn) = 3.75 * 10 power -19 / n