Question

Breakdown devices belonging to the category of solid-state devices are basically dependent on the phenomenon of
A. Zener Breakdown
B. Avalanche Breakdown
C. PN Junction Breakdown
D. All of these

Answer 1

This question is based on the concepts of the types of breakdowns and their applications. The Zener breakdown and the PN junction breakdowns occur in only devices named Zener diodes and PN junction diodes. The Avalanche breakdown occurs in diac, triac, SCS, SCR and other such devices.

Complete step by step answer:
First, let us know about the Zener, Avalanche and PN junction breakdowns.
Zener breakdown: This breakdown occurs at the heavily doped junctions which have narrow depletion layers. Across this narrow depletion layer, a very strong electric field will be set by the breakdown voltage. The junction will have a very low resistance because of a very strong electric field that produces a large number of current carries, which will lead to Zener breakdown. This breakdown only occurs in Zener diodes.
Avalanche breakdown: This breakdown occurs at the lightly doped junctions which have wide depletion layers. Across this wide depletion layer, a not so strong electric field will be set by the breakdown voltage, which is not strong enough to produce the Zener breakdown. The avalanche breakdown results because of the more collision between the newly generated charge carriers accelerated by the electric field. Here, the charge carriers are generated by the collision of the minority carriers with the semiconductor atoms in the depletion region, in turn, resulting in the formation of the electron-hole pairs.
PN Junction breakdown: The diode does not conduct under reverse bias condition. When a reverse voltage is applied and is increased, the depletion width gets increased and at this point called a breakdown point, the diode gets damaged and will start to behave as a shorted wire. The resistance nears to zero, thus, the current increase. This breakdown occurs only in PN junction diodes.
As, the breakdown devices belonging to the category of solid-state devices are basically dependent on the phenomenon of Avalanche Breakdown.

Thus, the option (B) is correct.

Note:
The important thing to remember is that the Zener breakdown occurs only in the Zener diodes and the PN junction breakdowns occur only in PN junction diodes. Whereas, the Avalanche breakdown occurs in many solid-state devices such as diac, triac, SCS, SCR and other such devices. So, the question is based on the applications of the breakdowns.