From the previous data, what electric field (in ) over the gradient zone of would be required to compensate the electron diffusion flux with an electron drift flux? The electron mobility in silicon is and the direction of drift to compensate diffusion flux is directed from lower density to higher density.

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0.69 V

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To calculate the electric field required to compensate the electron diffusion flux with an electron drift flux, you'll need to use Fick's first law of diffusion and the equation for drift current density.

Fick's first law of diffusion relates the diffusion flux to the concentration gradient:

J_diffusion = -Dn * (∇n)

where J_diffusion is the diffusion current density, Dn is the electron diffusion coefficient, and (∇n) is the concentration gradient.

The drift current density is given by:

J_drift = -q * μn * n * ∇V

where J_drift is the drift current density, q is the electron charge, μn is the electron mobility, n is the electron concentration, and ∇V is the electric field.

To compensate the diffusion flux, the drift current density should be equal in magnitude but opposite in direction to the diffusion current density:

J_diffusion = J_drift

Since the direction of drift to compensate the diffusion flux is from lower density to higher density, the gradient zone will be the region where the electron concentration is decreasing. Therefore, the concentration gradient ∇n in the diffusion equation will be negative.

Equating the two current densities and substituting in the appropriate values, we have:

-Dn * (∇n) = -q * μn * n * ∇V

Simplifying, we find:

∇V = (Dn/q * μn) * (∇n/n)

Now, you can calculate the electric field (∇V) required to compensate the electron diffusion flux in the gradient zone. Use the electron diffusion coefficient (Dn) and the electron mobility (μn) for silicon, which you mentioned are provided in the problem.

Please provide the values for Dn, μn, (∇n), and n to proceed with the calculation.