The diffusion capacitance of a forward biased p+

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The diffusion capacitance of a forward biased p⁺ – n junction diode with a steady current I depends on—

1. Width of the depletion region
2. Mean lifetime of the holes
3. Mean lifetime of the electrons
4. Junction area

Correct Option: B

The diffusion capacitance of a forward biased p⁺–n junction is given by

C_D =	I
	V_T

Where, = Mean life time of charge carriers
I = Forward current
C_D = Diffusion capacitance
V_T = Volt equivalent of temperature p+ – n → means p-layer is heavily doped than n-layer. It means the current at the junction is entirely due to holes. Thus diffusion capacitance of a forward biased p⁺ – n junction diode with a steady current I depends on mean life time of the holes.