What is Schottky Diode?

The Schottky Diode is an electronic component which is used to radio frequencies, RF functions like a mixer or a detector diode. It comes useful for functions having power because of possessing low forward voltage drop that would result in power loss at the least levels in comparison to the general PN junction diodes. In some cases, sometimes being addressed as the surface barrier diode or hot carrier diode.

How was Schottky Diode Discovered?

Most of us do not know that Schottky diode is actually the oldest semiconductor devices that still exists. Its symbol is normally applied in circuit diagrams as an ordinary diode symbol. But, it is necessary to use a particular symbol of Schottky diode to indicate that it must be used since it is necessary for the operation of the circuit. Therefore, a particular symbol of Schottky diode is deemed useful.

The symbol of Schottky Diode:

Schottky Diode

Schottky Diode Working:

Schottky Diode Working
  • The operation relies on the principle that the electrons in the different material have different potential energy.
  • N-type semiconductors have higher potential energy than electrons of metals.
  • When these two are brought into contact, there is a flow of electrons in both directions across the metal-semiconductor interface.
  • A voltage is applied to the Schottky so that the metal is positive when compared to the semiconductor.
  • The voltage opposes the built-in potential and makes the current flow easy.

Applications of Schottky Diode:

Schottky diodes have been useful for the industry of electronics that has spotted many applications in diode rectifier because of its unique properties. Here are some of the major areas it is widely used.

RF mixer and detector diode:

The Schottky diode consists of its radio frequency functions owing to its switching speed at the highest level and top frequency capability. The Schottky barrier diodes come handy for diode ring mixers with high performance.

Power rectifier:

The Schottky barrier diodes also have functions with high power as rectifiers. The high density of current and voltage drop with low forward show that the wastage of power is the least then the normal PN junction diodes.

Power OR circuits:

This diode would be useful for functions where two different power supplies drive a load like in a battery supply. It is important that the power coming from supply should not mix with the others.

Solar Cell Applications:

As we know,  the solar cells are usually linked to the batteries that are rechargeable, mostly batteries with lead acid since power supply must be necessary round the clock a day. Solar cells would not support the applied charge in reverse and thus a diode would be used in a proportional pattern of the solar cells.

Stay tuned with BYJU’S to learn more about Schottky diode, solar cell and much more.

Schottky Diode Important Questions

Q1. Name the diode that uses a metal-semiconductor junction.

Ans: Schottky diode uses a metal-semiconductor junction.

Q2. Name the metal-semiconductors used in the Schottky diode junction.

Ans: Al-Silicon is the metal-semiconductor used in the Schottky diode junction.

Q3. Why there is no reverse recovery time in a Schottky diode?

Ans: There are no stored charges as the metal-semiconductor junction is used, due to which the switching is faster.

Q4. What are the majority charge carriers in a Schottky diode?

Ans: Electrons are the majority charge carriers in a Schottky diode.

Q5. What does the silicon represent in the Schottky diode?

Ans: It represents n-type semiconductor as the p-type has limitations.

Q6. Why Schottky diode can be switched off much faster than the p-n junction diode?

Ans: As there is no recombination of charges, there is no reverse recovery time which makes switching off faster.

Q7. How to reduce the reverse recovery time of the diode?

Ans: The reverse recovery time of the diode can be reduced by using platinum and gold doping.

Q8. What is reverse recovery time?

Ans: Reverse recovery time of diode is defined as the time taken by the diode to regain its blocking capability.

Q9. What is a blocking diode?

Ans: Blocking diode is a diode used to direct the energy flow in one direction in a wire.

Q10. What are the other names of Schottky diode?

Ans: The other names of Schottky diode are:

  • Schottky barrier diode
  • Surface barrier diode
  • Majority carrier device
  • Hot carrier diode
  • Hot electron diode

Practise This Question

Find the current in the section PQ. A time varying field of 5t is applied. The wires have a resistance of 2Ω/m.