A `Ge` specimen is doped with `Al`. The concentration of acceptor atoms is `~10^(21) at oms//m^(3)`. Given that the intrinsic concentration of electron hole pairs is `~10^(19)//m^(3)`, the concentration of electron in the specimen is

Options

A. `10^(17)//m^(3)`
B. `10^(15)//m^(3)`
C. `10^(4)//cm^(3)`
D. `10^(16)//cm^(3)`

Answer

A

Explanation

`n_(i)^(2)=n_(h)n_(e) implies (10^(19))^(2) =10^(-21)xxn_(e) implies n_(e)=10^(17)//m^(3)`.