What is the difference between a PN junction diode and a Schottky diode?

A PN junction diode is formed by joining a p-type semiconductor with an n-type semiconductor, while a Schottky diode is formed by joining a metal with a semiconductor.

PN junction diodes are the most common type of diode and are used in a wide range of applications, including rectification, voltage regulation, and signal modulation. They are formed by joining a p-type semiconductor with an n-type semiconductor, creating a depletion region at the junction where the majority carriers are depleted and a potential barrier is formed. When a forward bias is applied, the potential barrier is reduced, allowing current to flow through the diode. When a reverse bias is applied, the potential barrier is increased, preventing current flow. To further understand the principles behind these processes, exploring the concept of physical quantities can provide a deeper insight.

Schottky diodes, also known as hot carrier diodes, are formed by joining a metal with a semiconductor, creating a Schottky barrier at the junction. They have a lower forward voltage drop and faster switching speed than PN junction diodes, making them useful in high-frequency applications such as RF circuits and power electronics. However, they have a higher reverse leakage current and are less suitable for high-voltage applications. Schottky diodes play a significant role in applications that harness the photoelectric effect, where the movement of electrons under light exposure is critical.

A-Level Physics Tutor Summary: A PN junction diode is made by connecting a p-type and an n-type semiconductor, useful in many electronics like rectifiers. A Schottky diode is made by connecting a metal to a semiconductor, better for fast switching and high-frequency uses, but it's not great for high-voltage tasks due to its higher reverse leakage current. Essentially, their construction and best uses differ.