The resistivity of n-type germanium is 0.01Omegam at room temperature. Find the donor concentration if the mobility of electrons is 0.39m^2//"volt"-sec.

The resistivity of n-type germanium is 0.01Omegam at room temperature.

1.	The resistivity of n-type germanium is 0.01Omegam at room temperature. Find the donor concentration if the mobility of electrons is 0.39m^2//"volt"-sec.
Answer» SOLUTION :Let `N_d`be the donor concentration. CONDUCTIVITY,`sigma-1/p=1/(0.01)=100astS//m` Now,`sigma=eN_dmu_e......N`type SEMICONDUCTOR or `N_d=sigma/(emu_e)=100/(1.6xx10^-19xx0.39)=1.6xx10^21//m^3`

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The resistivity of n-type germanium is 0.01Omegam at room temperature. Find the donor concentration if the mobility of electrons is 0.39m^2//"volt"-sec.

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