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What is the effect of doping on breakdown voltage?
In case of doping, the no. of charge carriers is increased, but the energy needed to lock out the valence electrons remains same. So, the breakdown voltage remains same.
Explanation: The maximum reverse bias voltage that can be applied to a p-n diode is limited by breakdown. The resulting breakdown voltage is inversely proportional to the square of the doping density if one ignores the weak doping dependence of the electric field at breakdown.
How doping affects the width of depletion region?
We can say depletion width decreases with increase in doping because it does but only relative to the doping on the other side of the pn junction. If each side of the junction has equal numbers of majority carriers then the same depletion region width is needed to uncover the same amount of space charge.
What kind of current does a light emitting diode need?
Like conventional PN junction diodes, light emitting diodes are current-dependent devices with its forward voltage drop VF, depending on the semiconductor compound (its light colour) and on the forward biased LED current. Most common LED’s require a forward operating voltage of between approximately 1.2…
How does the p-n diode affect the diffusion capacitance?
As a p-n diode is forward biased, the minority carrier distribution in the quasi-neutral region increases dramatically. In addition, to preserve quasi-neutrality, the majority carrier density increases by the same amount. This effect leads to an additional capacitance called the diffusion capacitance.
Where does the diode current occur in reverse bias?
Under forward bias, the diode current is due to recombination. This recombination can occur within the quasi-neutral regions, within the depletion region or at the metal-semiconductor Ohmic contacts. Under reverse bias, the current is due to generation.
What kind of dopant is used for light emitting diodes?
From the table above we can see that the main P-type dopant used in the manufacture of Light Emitting Diodes is Gallium (Ga, atomic number 31) and that the main N-type dopant used is Arsenic (As, atomic number 33) giving the resulting compound of Gallium Arsenide (GaAs) crystalline structure.