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The potential across a pn junction is called potential barrier because majority charge carriers have to overcome this potential before crossing the junction.
Potential barrier is the energy inserted in order to go against the passage of electron.
The forward voltage of a semiconductor junction, silicon or germanium, changes by -2mV for every rise in temperature of 1 degree C, so your friend is correct
The potential barrier on the basis of p-type and n-type semiconductor is the space created by the depletion layer that charged particles need sufficient energy to overcome.
Cut in voltage is the minimum voltage required to overcome the barrier potential. In other words it is like trying to push a large boulder....it may not be possible to push a large boulder by one person but it may be done if 2 or more people try to push it together depending on the size of the boulder.....similarly....the charge carriers in the barrier region have a potential energy of about 0.6V for Silicon and about 0.2V for Germanium. so in order for the diode to conduct, it is required to overcome the potential of the charge carriers in the junction barrier region and hence only if a potential more than that of the barrier potential (cut off voltage) is applied, then electrons flow past the junction barrier and the diode conducts.
Yes, it varies inversely, i.e. as temperature increases the barrier potential decreases. It decreases by 2mV for degree Celsius rise of temperature.
barrier potential P0=(kT/q)*ln(Na*Nd/Ni^2) when T ↑, P0↑.
barrier potential P0=(kT/q)*ln(Na*Nd/Ni^2) when T ↑, P0↑.
The barrier potential may depend on the exact material; but you can't normally change that. It may also depend on temperature.Also, such a barrier potential is not fixed at some value (like 0.7 V); however, it's often close enough that you can consider it to be constant. But actually, the barrier potential depends on the current. At higher currents, the potential is slightly higher.
The potential across a pn junction is called potential barrier because majority charge carriers have to overcome this potential before crossing the junction.
Breakdown voltage is far greater than barrier potential. silicon:- break-down voltage :- 5v - 450 v barrier potential ;- 0.5v to 0.7 V
The potential barrier of a diode is caused by the movement of electrons to create holes. The electrons and holes create a potential barrier, but as this voltage will not supply current, it cannot be used as a voltage source.
Potential barrier of silicon is 0.7, whereas potential barrier of germanium is 0.3
0.3 volt
Forward bias is when the height of the depletion layer is reduced such that a greater number of majority charge carriers have sufficient energy to overcome the potential barrier while revers bias is when the height of the potential barrier is increased so that very few majority charge carriers have sufficient energy to surmount the potential barrier. All the above phenomena takes place when a potential barrier is applied across the pn junction.
Barrier
Potential barrier is the energy inserted in order to go against the passage of electron.