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so that its depletion layer is narrower... when a high reverse voltage is applied across the junction the electron hole generation takes place.....

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Q: Why zener diodes are heavily doped?
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What is conductivity of n type semiconductor?

What's the silicon doped with? Antimony? Arsenic? Phosphrus? And, much more importantly, how heavily is the silicon doped? Are there 1020 electrons per meter-3 or is 1025 electrons per meter-3 more the order of the day? Graphite is used as a conductor in some electrochemical cells. Processed and compressed graphite is used as brush material in electric motors. Without more information, the best answer that can be offered is a bit general. What is the electrical conductivity of n-type silicon graphite? Pretty good.


What is the most conductive material on earth?

Effective is an interesting choice of word : depending on usage the answer is gold, silver, aluminum, copper, or heavily doped silicon ... resistance to corrosion, conductivity, light weight, availability, or location.


What happens when divalent impurity is doped with trivalent element?

will there be any structural changes when divalent is doped with trivalent


Do compound semiconductors behave as intrinsic semiconductors?

Intrinsic refers to the doping -- intrinsic semiconductors are not doped. Whether compound or not, if they are not doped they are intrinsic.


How does the selenium diode work?

Selenium diodes work much like any other diode. They allow current to flow in a forward direction and block current from flowing in the opposite direction. They have a higher forward bias voltage then silicon and as such generate much more heat then a comparable silicon diode. Most selenium diodes will therefore have an integrated heat sink that helps to dissipate all the heat generated. As a zener diode, selenium is used in surge suppression where its heat sink helps in survivability during a surge. However, its low alpha (measure of nonlinearity) means that the voltage during a surge is very high and usually unsuitable to be used as protective device without other components in parallel. The reverse voltage is about 26 Volts, so to get higher voltage zener diode, many are placed in series. By connecting them back to back, then a bidirectionial zener diode can be created. Selenium diode were very common in the 1950s and can be seen in industrial applications of the time. Some model train power supplies were seen to use these components. Since the advent of silicon diodes and their more efficient operation, these part have disappeared from use.

Related questions

What is the difference between an ideal zener diode and practical zener diode?

Zener diode is heavily doped pn junction diode.


Basic construction of zener diode?

A zener diode has a heavily doped p-n junction allowing electrons to tunnel from the valence band of the p-type material to the conduction band of the n-type material, such that the reverse voltage is "clamped" to a known value, called the zener voltage.


How will you differentiate the diodes whether it is zener or an avalanche when you are given two diodes of rating 6.2V and 24V?

Silicon "zener diodes" with a zener voltage rating of 5.6V or higher operate mainly by avalanche breakdown, so both the 6.2V and 24V "zener diodes" are avalanche breakdown type (not zener breakdown type).


In what region of their characteristic curve are zener diodes operated?

Zener diodes are normally operated in their reverse breakdown voltage curve.


Why current flow from cathode to anode in zener diode?

First off, I don't know if by current flow you mean conventional current flow or electron current flow. You realize they are in opposite directions and most electronics engineers use conventional current flow in circuit analysis.Ignoring this, I will assume your real question is "Why does current flow backwards in zener diodes compared to ordinary diodes?" The answer is that zener diodes are not operated in the forward biased range as are ordinary diodes, instead they are operated in the reverse biased range. When reverse biased enough any diode reaches breakdown voltage and suddenly conducts. Most ordinary diodes can be destroyed by breakdown, but zener diodes are designed to tolerate it. In zener diodes, this breakdown is referred to as "zener breakdown" and the voltage it happens at the "zener voltage".Low voltage zener diodes can still be used in the forward biased mode, like ordinary diodes. However most high voltage zener diodes have a "blocking diode" that is not documented on the data sheet to block forward biased operation. "Blocking diodes" are simply ordinary diodes wired in series with the zener; when the zener would be forward biased they are reverse biased (and thus blocking current), when the zener would be reverse biased they are forward biased.


Zener diodes are most commonly used in?

Zener diodes are a form of semiconductor diode that are widely used in electronics circuits as voltage references. Zener diodes provide a stable and defined voltage and as a result Zener diode circuits are often used in power supplies when regulated outputs are needed. Zener diodes are cheap and they are also easy to use and as a result they are used in many applications and many circuits.


How replace branches of diode with zener diode?

You do not want to replace diodes with zener diodes. They are not the same type of device, and the design objective is not the same.


Why zener diodes are made transparent?

sadasx


Difference between zener diode and junction diode?

Zener diodes and ordinary junction diodes are similar, except that zener diodes have additional doping to bring their reverse breakdown voltage into a more usable value, and to allow them to not destructively avalanche when they do conduct in the reverse direction.


Different between schottky diode and zener diode?

pn junction diode conducts current in one directions where as the zener diode conducts in both the directions. large current flow damage the PN junction diode but zener diode conducts eventhough there is a large current........


How zener diode differ from normal p-n junction diode?

Zener diodes differ from normal p-n junction diodes in that they have a reduced reverse breakdown voltage and, in fact, we normally operate zener diodes in reverse bias to take advantage of the relatively stable voltage regulation it provides.


What are the features of Zener diode?

By varying doping levels ,it is possible to produce zener diodes with varying breakdown voltages.