The drift current

Drift current, I_d = 20μA

Where, N_e= Number of electrons crossing a cross section per second

N_h= Number of holes crossing a cross section per second

e= magnitude of charge on an electron/hole = 1.6×10^-19 C

Without any biasing applied on the junction, N_e = N_h = N

I_d=2N×e

N=6.25×10¹³