Power diodes are structurally different from normal low-power diodes for use in high-power circuits. It is made up primarily of silicon but contains boron, gallium, arsenide, germanium or phosphorous in size-able quantities. Power diodes contain free electrons that help in current transfer.
Power diode generally works under two conditions, forward bias and reverse bias. In diodes, the current is mainly due to electrons or electron vacancies called holes. In forward bias, the power diodes help to maintain electric current by providing minimal resistance to flow in a particular direction while in reverse bias, they don't allow the current to flow by providing optimal resistance.
Power diodes types include high current diodes, high voltage diodes, PN power diodes, PIN power diodes, RF power diodes, switching power diodes, Schottky power diodes and rectifier power diodes. Among these the PN power diodes, PIN power diodes and RF diodes are more commonly used.PIN Power diode is a three layered semiconductor consisting of an intrinsic layer (layer of pure material) sandwiched between P and N layers.