Pure `Si` at `500K` has equal number of electron `(n_(e))` and hole `(n_(h))` concentration of `1.5xx10^(16)m^(-3)`. Dopping by indium. Increases `n_(h)` to `4.5xx10^(22) m^(-3)`. The doped semiconductor is of

Options

A. `n`-typpe with electron concentration
`n_(e)=2.5xx10^(23)m^(-3)`
B. `p`-type having electron concentration
`n_(e)=5xx10^(9)m^(-3)`
C. `n`-type with electron concentration
`n_(e)=5xx10^(22m^(-3)`
D. `p`-type with electron concentration
`n_(e)=2.5xx10^(10)m^(-3)`

Answer

B

Explanation

`n_(i)^(2)=n_(e)n_(h)`
`(1.5xx10^(16))^(2)=n_(e)(4.5xx10^(22))`
`n_(e)=0.5xx10^(10)=5xx10^(9)`
`n_(h)=4.5xx10^(22)`
`n_(h)gtn_(e)(p-type)`