(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An extrinsic semiconductor sample of cross section A and length L is doped in such a way that the doping concentration varies as N_{d}=N_{0}Exp(-x/L)

Assume that mobility μ of the majority carriers remain constant.What is the resistance of the sample?

2. Relevant equations

σ=neμ

ρ=1/σ

R=Lρ/A=L/(Aμen)

3. The attempt at a solution

In the eqn n is the free electron concentration.

I thought this will be eqal to doping concentration.

then,R = L/(AμeN_{o}Exp(-x/L))

But this is not the right answer.

Can this resistance be varrying with x since doping concentration depend on x?

Thanks.

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# Homework Help: Doped semiconductor-to find the resistance?

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