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Name the breakdown mechanism in a highly doped p-n junction under reverse biased condition |
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Answer» ong>Answer: Solution:A Zener diode is also a p-n junction which is always connected in reverse biased and the same phenomenon happens in it called Zener breakdown.Avalanche breakdown Avalanche breakdown occurs in lightly-doped p-n junctions where the depletion region is comparatively LONG and the reverse voltage increases beyond 5 V.avalanche breakdown Avalanche Breakdown occurs in a p-n junction diode which is moderately doped and has a thick junction (means depletion layer width is high). It occurs when a high reverse voltage is applied across the diode. So as the applied reverse voltage is INCREASED, the electric field across junction keep increasing. This electric field exerts a force on electrons at the junction and it frees them for covalent bonds. This results in a COLLISION with neighboring atoms. As a result, electron-hole RECOMBINATION takes place across the junction. This results in net current that rapidly increases. |
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