Whenever two dissimilar conductors touch a "potential barrier" forms. All conductive materials have a voltage above zero that an electron must have to enter the material. In true conductors, this voltage is very low. In semiconductors, it can vary, but is usually in the 0.25 to 6.8 Volt range. In insulators, it can be very, very high. When two semiconductors or a metal and a semiconductor touch the difference is polarity sensitive. The higher the "band gap", the voltage that must be overcome to enter the "conduction band", the higher the voltage drop in the forward bias direction. Think of the "band gap", or potential barrier, as being like a curb on a road and sidewalk. It's easy to ride a bike off the sidewalk over the curb onto the road, but not so easy the other way.
Diffusion of majority carriers across the junction
Barrier potential in a pn junction is caused by the presence of bound and mobile charges on either sides of the pn junction.
The built in potential in a pn junction. Due to the difference in carrier concentration between the sides of a pn junction. Diffusion potential increases with increase in doping levels.
ginago
The voltage across a forward-biased PN junction in a semiconductor diode or transistor.
the material in which using for doping is already neutral.,,so the pn-junction diode also neutral........
when a p-n junction is formed electrons from the neutral N type goes to neutral P type. In the junction there will not be any electron or hole. In the junction because of earning electrons, P side becomes negative(ion) , & N side becomes positive(ion). So there will be a potential deference . This is known as the BARRIER......
The potential across a pn junction is called potential barrier because majority charge carriers have to overcome this potential before crossing the junction.
The built in potential in a pn junction. Due to the difference in carrier concentration between the sides of a pn junction. Diffusion potential increases with increase in doping levels.
ginago
When light falls on the junction of a pn junction/diode the potential barrier gets break down due to majorty of electrons flow and they release energy in the form of light.
When the pn junction is forward biased,the height of the potential barrier is reduced allowing more majority charge carriers ti flow across the junction and when it is reversed biased, the height of the potential barrier increases there b reducing the majority charge carrier that have sufficient energy to flow across the junction.
Potential barrier is the energy inserted in order to go against the passage of electron.
The voltage across a forward-biased PN junction in a semiconductor diode or transistor.
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.
This is a characteristics of semiconductor diode {pn junction}.In forward biasing here we connect p to positive terminal and n -ve terminal when external voltage is aplied in such a direction that cancels out potential barrier thus permitting current flow In reverse biasing the connection of pn junction is inverted but in this the potential barrier incresesand offers resistance to current flow but at a certain voltage current increases suddenly(the break down voltage)the zener diode works in this principle
barrier voltage decreases by 2mV for every 1 degree increase in temperature.
A pn junction can be formed by bringing the p and n type materials together.
I cannot think of any, but a pn junction is a part of a diode and has a rectifying properties.