How do Schottky diodes conduct electricity?

How do Schottky diodes conduct electricity?

The advantages of Schottky diodes are low impedance, small forward voltage drop, and fast recovery speed, so they are commonly used in high-frequency high current rectification and power down protection circuits. Schottky diodes are also conductors with excellent conductivity, so how do Schottky diodes conduct electricity?

Unidirectional conductivity is the most important characteristic of Schottky diodes. In a circuit, current can only flow in from the positive pole of a Schottky diode and out from the negative pole. The following is a simple experiment to illustrate the forward and reverse characteristics of Schottky diodes.

The forward characteristic is like in an electronic circuit, when the positive pole of a Schottky diode is connected to the high potential end and the negative pole is connected to the low potential end, the Schottky diode will conduct. This connection method is called forward bias. It must be noted that when the forward voltage applied to both ends of the Schottky diode is small, the Schottky diode still cannot conduct, and the forward current flowing through the Schottky diode is very weak.

Only when the forward voltage reaches a certain value (referred to as the "threshold voltage", which is about 0.2V for germanium tubes and 0.6V for silicon tubes), can the Schottky diode conduct directly. After conduction, the voltage at both ends of the Schottky diode remains basically unchanged (about 0.3V for germanium tubes and 0.7V for silicon tubes), known as the "forward voltage drop" of the Schottky diode.

In electronic circuits, the positive pole of a Schottky diode is connected to the low potential end and the negative pole is connected to the high potential end. At this time, there is almost no current flowing through the Schottky diode, and the Schottky diode is in the cut-off state. This connection method is called reverse bias. When the Schottky diode is in reverse bias, there will still be a weak reverse current flowing through the Schottky diode, known as leakage current. When the reverse voltage at both ends of the Schottky diode increases to a certain value, the reverse current will sharply increase, and the Schottky diode will lose its unidirectional conductivity. This state is called the breakdown of the Schottky diode.

The switching of forward and reverse features in Schottky diodes forms the current conductivity of Schottky diodes. Under this conductive performance, Schottky diodes better utilize their own advantages and maximize their conductivity.