Question

The number of silicon atomes per $m^3$ is $5\times {10}^{28}$ . This is doped simultaneously with $5\times {10}^{28}$ atoms per $m^3$ of Arsenic and $5\times {10}^{20}$ per $m^3$ atoms of Indium. Calculate the number of electrons and holes. Given that $n_1=1.5\times {10}^{16}{m}^{-3}$ . Is the material $n$ -type or $p-$ type?

Answer 1

The number of electron is given as

$n_e=5\times {10}^{22}-5\times {10}^{20}$

Number of holes is given as

$n_h=\frac{n_i^2}{n_e}$

By substituting the values in the above equation we get

$n_h=4.54\times {10}^9{m}^{-3}$

Since number of electron is greater than holes so it is n-type.