Phosphorous is added to make an n-type silicon semiconductor with an electrical conductivity of 1.75 (Ωm)-1 . Calculate the necessary number of charge carriers required

The necessary number of electron charge carriers required is:

8.1019 × 10¹⁹ electrons/m³

Explanation:

The necessary number of charge carriers required can be determined from the resistivity. Given that, the phosphorus  make an n-type of silicon semiconductor;

Resistivity

where;

The number of electron on the charge carriers is unknown??

The charge of the electron q =

The electron mobility   = 0.135 m²/V.s

The electrical conductivity = 1.75 (Ωm)⁻¹

Making    the subject from the above equation:

Then;

electrons/m³

Thus; the necessary number of electron charge carriers required is:

8.1019 × 10¹⁹ electrons/m³

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