physics.cie said:I want to know that when a pn junction diode is formed and barrier potential is setup then how can we determine the same theoretically. Also I wan to know that is there any relation between barrier potential and energy band gap
Small band gap small barrier? ?
physics.cie said:Ok,bt when pn junction diode is formed then barrier potential is setup which can be determined practically, is thr any way to find barrier potential theoritically?
Barrier potential, also known as built-in potential, is the voltage difference that exists between the p and n regions of a pn junction diode when it is in equilibrium. This potential creates a barrier for the flow of majority carriers, and is a key factor in the functioning of the diode.
The barrier potential can be calculated using the following formula: VB = (kT/q) * ln(NAND/ni2), where k is the Boltzmann constant, T is the temperature in Kelvin, q is the electronic charge, NA and ND are the doping concentrations of the p and n regions, and ni is the intrinsic carrier concentration of the semiconductor material.
The barrier potential of a pn junction diode is affected by the doping concentrations of the p and n regions, the temperature, and the type of semiconductor material used. Increasing the doping concentrations or the temperature will result in a decrease in barrier potential, while using a different semiconductor material can also change the barrier potential.
The barrier potential is a crucial factor in the functioning of a pn junction diode. It creates a barrier for the flow of majority carriers, allowing the diode to act as a one-way valve for electric current. When a forward bias is applied, the barrier potential decreases, allowing current to flow through the diode. Conversely, when a reverse bias is applied, the barrier potential increases, preventing current from flowing.
Yes, the barrier potential of a pn junction diode can be changed by altering the doping concentrations of the p and n regions, or by changing the temperature. Additionally, using a different semiconductor material can also change the barrier potential. However, the barrier potential cannot be completely eliminated, as it is a fundamental property of a pn junction diode.