In semiconductor the concentrations of electron and holes are `8xx10^(18)//m^(3)` and `5xx10^(18)//m` respectively. If the mobilities of electrons and hole are `2.3 m^(2)//`volt-sec and `0.01m^(2)//` volt-sec respectively, then semicondutor is

Options

A. n-type and its resistivity is 0.34 `Omega`-m
B. p-type and its resistivity is 0.034 `Omega`-m
C. n-type and its resistivity is 0.034 `Omega`-m
D. p-type and its resistivity is 3.4 `Omega`-m

Answer

A

Explanation

As `n_(e) gt h_(h)`, so semiconductor is n-type.
Also, conductivity `(sigma)=(1)/("Resistivity"(rho))=e(n_(e)mu_(e)+n_(h)mu_(h))`
`rArr (1)/(rho)=1.6xx10^(-19)[8xx10^(18)xx2.3+5xx10^(18)xx0.01]`
`rArr =0.034 Omega`-m