The number of silicon atoms per \mathrm{m}^{3} is 5 \times 10^{28} . This is doped simultaneously with \mathbf{5} \times 10^{22} atoms per \mathrm{m}^{3} of Arsenic and 5 \times 10^{20} per \mathrm{m}^{3} atoms of Indium. Calculate the number of electrons and holes.
The number of silicon atoms per \mathrm{m}^{3} is 5 \times 10^{28} . This is doped simultaneously with \mathbf{5} \times 10^{22} atoms per \mathrm{m}^{3} of Arsenic and 5 \times 10^{20} per \mathrm{m}^{3} atoms of Indium. Calculate the number of electrons and holes.

Number of silicon atoms is given as N=5 \times 10^{28} atoms / \mathrm{m}^{3}

Number of arsenic atoms is given as \mathrm{n}_{\mathrm{AS}}=5 \times 10^{22} atoms / \mathrm{m}^{3}

Number of indium atoms is given as n_{\ln }=5 \times 10^{22} atoms / \mathrm{m}^{3}

n_{i}=1.5 \times 10^{16} electrons / \mathrm{m}^{3}

n_{e}=5 \times 10^{22}-1.5 \times 10^{16}=4.99 \times 10^{22}

n_{h} be the number of holes.

In the thermal equilibrium, n_{e} n_{h}=n_{i}^{2}

On Calculating, we get

n_{h}=4.51 \times 10^{9}

As a result, the material is a n-type semiconductor as n_{e}>n_{n}.