At 300 K, intrinsic silicon has a hole concentration of 7 × 10¹⁵ m⁻³. If antimony is introduced into silicon at the rate of 1 atom per 10⁷ silicon atoms, and only one-half of the impurity atoms supply electrons to the conduction band, by what factor does the charge-carrier concentration ri

Question

At 300 K, intrinsic silicon has a hole concentration of 7 × 10¹⁵ m⁻³. If antimony is introduced into silicon at the rate of 1 atom per 10⁷ silicon atoms, and only one-half of the impurity atoms supply electrons to the conduction band, by what factor does the charge-carrier concentration rise because of doping? Take the number of silicon atoms in 1 m³ to be 5 × 10²⁸.

Accepted Answer

1.8 × 10⁵. The doping introduces a significant number of electrons into the conduction band, calculated by determining the number of antimony atoms in 1 m³ of silicon and considering that half of these contribute to electron concentration. This results in a charge-carrier concentration increase of 1.8 × 10⁵, which reflects the effective contribution of the dopant.

Solution

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