how is zener diode fabricated so as to make it a special purpose diode?explain the significance of break down voltage in zener diode.

Asked by jaspreet singh | 27th Feb, 2011, 02:53: AM

Expert Answer:

Dear student,
 
The zener diode ( Breakdown diodes)  is a silicon p-n junction semiconductor device which is generally operated in its reverse breakdown region.The zener diodes are fabricated with precise breakdown voltages, by controlling the doping level during manufacturing. Zener diodes have breaking voltages ranging from 3v to 200 v. 
 
significance of break down voltage in zener diode.: 
The breakdown characterisitics of a zener diode is important because it is the operating region of the diode. when the reerse voltage applied to a zener diode is increased, initially the current through it is very small. This is the reverse leakage current of the diode. At certain reverese voltage current through it increases rapidly. The change from low value to higher value of current is well defined and very sharp. Such a sharp change in the reverse characterisitics is called knee or zener knee. (in the curve) At this knee, a breakdown is said to occur . The reverse bias voltage at wich this breakdown occurs is called the zener breakdown volatge. The zener breakdown voltage is carefully set by controlling the doping level during manufacturing.
 
Hope this helps.
Thanking you
Team
Topperlearning.com

Answered by  | 27th Feb, 2011, 06:34: AM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.