Step 4: Schottky Diodes
For the junction, molybdenum, platinum, chromium or tungsten are used; and a semiconductive an N-type silicon. The metal side acts as the anode and N-type semiconductor acts as the cathode. This is called the Schottky barrier. There are advantages in speed because Schottky diodes do not rely on holes or electrons recombining when they enter the opposite type of region as in the case of a conventional diode. These kinds of diodes, by design, have a very precise breakdown voltage, and are able to respond, or switch, rapidly due to having a partially metal junction.
When current flows through a diode there is a very small voltage drop across the terminals. This lower voltage drop is conducive of faster switching speed and better system efficiency. It reduces the power losses normally incurred in the rectifier and other diodes used within the power supply. With standard silicon diodes offering the main alternative, their turn on voltage is around 0.6 to 0.7 volts. With Schottky diode rectifiers having a turn on voltage of around 0.2 to 0.3 volts, there is a significant power saving to be gained.