In a Schottky diode, a junction is formed between a metal and a semiconductor. Let's discuss the details of this junction and the working of a Schottky diode.

Junction Formation:
The Schottky diode, also known as a hot carrier diode, is formed by bringing a metal and a semiconductor into contact. The metal used is typically a low work function material, such as aluminum, platinum, or tungsten. The semiconductor used is typically n-type, although p-type semiconductors can also be used.

Working Principle:
The Schottky diode operates based on the principle of the Schottky barrier, which is formed at the junction between the metal and the semiconductor. When the metal and semiconductor are brought into contact, a depletion region is formed at the junction due to the difference in energy levels between the metal and the semiconductor. The electrons from the semiconductor move towards the metal, creating a negative charge in the semiconductor and a positive charge in the metal.

Key Points:
- A Schottky diode is formed by a junction between a metal and a semiconductor.
- The metal used is typically a low work function material.
- The semiconductor used is typically n-type, but p-type semiconductors can also be used.
- The working principle is based on the formation of a depletion region at the junction due to the difference in energy levels between the metal and the semiconductor.
- Electrons from the semiconductor move towards the metal, creating a negative charge in the semiconductor and a positive charge in the metal.

Advantages of Schottky Diode:
- The Schottky diode has a lower forward voltage drop compared to other diodes, such as p-n junction diodes.
- It has a faster switching speed due to the absence of minority carrier storage time.
- The reverse recovery time of a Schottky diode is very short.
- It has a lower junction capacitance, making it suitable for high-frequency applications.

Conclusion:
In conclusion, a Schottky diode is formed by a junction between a metal and a semiconductor. The metal and semiconductor combination creates a depletion region, which enables the diode to exhibit specific characteristics such as low forward voltage drop, fast switching speed, and short reverse recovery time.