In a silicon junction diode, the region of the planar junction between n-type and p-type semiconductors can be approximately represented as two adjoining slabs of charge, one negative and one positive. Away from the junction, outside these charge layers, the potential is constant, with a value of Vn in the n-type material and Vp in the p-type material. Given that the difference between Vp and Vn is 0.3 V, and that the thickness of each of the two slabs of charge is 0.01 cm, find the charge density in each of the two slabs, and make a graph of the potential V as a function of position through the junction.
What is the strength of the electric field at the midplane?