Estimate the proportion of boron impurity which will increase the conductivity of a pure silicon sample by a factor of 100. Assume that each boron atom creates a hole and the concentration of holes in pure silicon at the same temperature is 7×1015 holes per cubic metre. Density of silicon is 5×1028 atoms per cubic metre.

Estimate the proportion of boron impurity which will increase the cond

1.	Estimate the proportion of boron impurity which will increase the conductivity of a pure silicon sample by a factor of 100. Assume that each boron atom creates a hole and the concentration of holes in pure silicon at the same temperature is 7×1015 holes per cubic metre. Density of silicon is 5×1028 atoms per cubic metre.
Answer» Estimate the proportion of boron impurity which will increase the conductivity of a pure silicon sample by a factor of 100. Assume that each boron atom creates a hole and the concentration of holes in pure silicon at the same temperature is $7 \times 10^{15}$ holes per cubic metre. Density of silicon is $5 \times 10^{28}$ atoms per cubic metre.

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