When the Avalanche breakdown in a diode occurs?
Therefore, Avalanche breakdown in a diode occurs when the reverse bias exceeds a certain value. Hence, the option (C), reverse bias exceeds certain value is the correct.
How does breakdown occur in diode?
“Break down” of a diode occurs during its reverse biased condition. We all know, under reverse bias the positive terminal of battery is connected to n side and the negative terminal of battery is connected to p side. At a point which we can call as “breakdown point”, the diode will get damaged.
What is meant by Avalanche breakdown?
Avalanche breakdown (or “the avalanche effect”) is a phenomenon that can occur in both insulating and semiconducting materials. It is a form of electric current multiplication that can allow very large currents within materials which are otherwise good insulators. It is a type of electron avalanche.
What is avalanche in a diode?
Avalanche occurs in diodes when the voltage across a diode exceeds a specified value. An avalanche diode is a diode that is designed to break down and conduct at a specified reverse bias voltage. This is somewhat similar, but not identical to Zener breakdown.
What is the main cause of avalanche breakdown?
Avalanche breakdown usually occurs when a high reverse voltage is applied across the diode. So as we increase the applied reverse voltage, the electric field across the junction will keep increasing. This generated electric field exerts a force on the electrons at the junction and it frees them from covalent bonds.
What phenomenon in electronics does an avalanche breakdown primarily dependent?
collision
Avalanche breakdown is primarily dependent on this phenomenon of collision.
What is avalanche and zener breakdown?
Avalanche breakdown occurs due to the rapid collision of electrons with other atoms. Zener breakdown occurs because of the high electric field. Zener breakdown is the controlled version of Avalanche breakdown in a modified p-n junction.
What is an avalanche breakdown in pn junction?
The avalanche breakdown in p-n junction is due to cumulative effect of conduction band electron. In reverse bias, due to applied electric field, electrons acquire enough energy to free more electron bound to the atom. The abundant number of electron-hole pairs are created for conduction, this is cumulative effect.
How do electrons release in avalanche breakdown?
This “avalanche” process is complicated by the production of extra hole-electron pairs by the leftward moving holes. In fact, avalanche “breakdown” occurs when the net electron and hole gains across the space-charge region add to unity, since the avalanche becomes self-sustaining.
For which voltages avalanche break down effect dominates?
Zener breakdown (the breakdown mechanism described by Clarence Zener) occurs in practical semiconductor devices at low voltages. Avalanche breakdown dominates at high voltages and includes amplification by carrier-generating processes similar to a small rockfall initiating an avalanche.