Fundamentals of p – n Junction

 In this chapter, fundamentals of the p – n junction, electric field across the junction, equilibrium carrier concentration on each side, etc., have been briefly discussed. Expression of built-in potential in terms of carrier density has been derived. Magnitudes of the current under zero, forward, and reverse biased conditions have been calculated. Unlike a resistor, p – n junction corresponds to static, dynamic and average ac resistance, and they have been briefly discussed here along with protocol to examine their values. These p – n junctions also exhibit capacitance, namely transition capacitance and diffusion capacitance. Herein, these parameters and their relevance in current-voltage characteristics of p – n junction and applicational aspects have been elaborated.