$5\mathrm{.}16$ In a p$-$n junction diode acceptor, donor and intrinsic carrier concentrations are $\frac{{10}^{17}}{c}{m}^3,\frac{{10}^{18}}{c}{m}^3,$ and $\frac{{10}^{10}}{c}{m}^3,$ respectively. The relative dielectric constant for the material of the diode is $12.$ The diffusion coefficients are $D_n=49c\frac{m^2}{sec}$ and $D_p=18c\frac{m^2}{sec},$ respectively. Electron and hole carrier lifetimes are the same, $25$ ns $.$ Under forward bias of $0\mathrm{.}2$ V $,$ calculate the electron diffusion current density at a distance of twice of the diffusion length.