Consider that the concentration of electrons in a semiconductor bar varies linearly from 2 × 10¹⁷ cm⁻³ at x = 1 μm to 1 × 10¹⁶ cm⁻³ at x = 4 μm along the x-direction. Assume that the concentration of electrons is not varying along other directions (that is along y- and z-directions).
[Given: the mobility of electron is 1400 cm²V⁻¹s⁻¹, thermal voltage is 25 mV and electronic charge is 1.6× 10⁻¹⁹ Coulomb.]
The density of electron diffusion current (in A/mm²) is __.
(rounded off to two decimal places)