A p *n junction is one in which the doping concentration in the p region is much greater than that in the n region. In such a junction, the forward current is mostly due to hole injection across the junction. Show that I = Ip = For the specific case in which ND = 1016 /cm3, Dp = 10 cm2 / s, Lrp= 10 mu m, and A = 104 mu m2, find Is and the voltage V obtained when I = 0.5 mA. Assume operation at 300 K where ni = 1.5 Times 10 10/cm3.

Consider a large isothermal enclosure that is maintained at a uniform temperature of 2000 k. calculate the emissive power of the radiation that emerges from a small aperture on the enclosure surface. what is the wavelength ? , below which 10% of the emission is concentrated? what is the wavelength ? 2 above which 10% of the emission is concentrated? determine the wavelength at which maximum spectral emissive power occurs. what is the irradiation incident on a small object placed inside the enclosure?