The purpose of a Schottky barrier diode (SBD) in rectification is to convert alternating current (AC) into direct current (DC). Rectification is the process of converting the oscillating voltage and current of an AC signal into a unidirectional flow of current, which is the characteristic of DC.
A Schottky barrier diode is a special type of diode that utilizes a metal-semiconductor junction instead of the typical P-N junction found in regular diodes. The metal-semiconductor junction is formed between a metal (e.g., aluminum) and a semiconductor material (e.g., silicon). The key feature of the Schottky barrier diode is the formation of a Schottky barrier at the junction, which results in some unique properties that make it well-suited for rectification applications.
The primary purpose of using a Schottky barrier diode in rectification is due to its lower forward voltage drop compared to regular P-N junction diodes. Traditional P-N diodes have a relatively higher forward voltage drop (typically around 0.7 volts for silicon diodes), which leads to some power loss during rectification. Schottky barrier diodes, on the other hand, have a much lower forward voltage drop (around 0.2 to 0.4 volts), resulting in reduced power losses during the rectification process.
As a result of this lower voltage drop, Schottky barrier diodes are more efficient at converting AC to DC. They are commonly used in high-frequency rectification applications, such as in switching power supplies and RF (radio frequency) circuits, where minimizing power losses is critical.
In summary, the purpose of a Schottky barrier diode in rectification is to improve the efficiency of the rectification process by reducing the forward voltage drop and, consequently, reducing power losses, especially in high-frequency applications. This makes SBDs suitable for various power conversion and rectification tasks in electronic devices.