Today we will discuss about the depletion region in greater detail than before. We will derive a quantitative relation among barrier potential and its width which are created in the depletion region, as discussed before. We will also derive an expression for the electric field that is established due to this potential.
Lets first recall how electric field and electric potential are related to each other. Electric field is the negative potential gradient. Mathematically, in 1 dimension this is expressed by the following formula.