How does the doping concentration in a zener diode compare to a crystal diode? ______________ that of a crystal diode
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Answer: C. more than
Explanation
Zener diodes require extremely heavy doping concentrations to create an extremely narrow depletion region. This narrow depletion zone enables quantum tunneling and sharp reverse breakdown characteristics at precise voltages. Therefore, the doping concentration in a Zener diode is significantly more than that of a crystal diode. Doping involves adding specific impurity atoms to semiconductor silicon to alter its electrical conductivity. Higher doping levels drastically narrow the width of the depletion layer formed at the p-n junction boundary. This narrow depletion region allows Zener breakdown to occur at low reverse voltages without damaging the device.
The same doping concentration would cause the Zener to behave like a standard diode with normal breakdown. Less than doping is incorrect because lower impurity levels widen the depletion region and raise breakdown voltages. None of the above is incorrect since heavier doping is the defining manufacturing feature of Zener diodes.
- Subject
- Engineering
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- Electrical Engineering
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- medium
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