Graph of Potential, Charge Density, and Electric Field in a p-n Junction Diode

A p-n junction diode is a semiconductor device that consists of a p-type semiconductor and an n-type semiconductor. The region where the p-type and n-type semiconductors meet is called the depletion region. The depletion region is a region where there are no free charges. When a voltage is applied across the p-n junction, the depletion region acts as a barrier to the flow of current.

Potential Graph

The potential graph shows the variation of potential across the p-n junction. The potential is negative on the n-type side and positive on the p-type side. The potential barrier is the difference in potential between the two sides of the junction. The potential barrier prevents the flow of current until the external voltage is sufficient to overcome the barrier.

Charge Density Graph

The charge density graph shows the variation of charge density across the p-n junction. The charge density is positive on the p-type side and negative on the n-type side. The depletion region has a charge density of zero. The charge density is highest at the edges of the depletion region.

Electric Field Graph

The electric field graph shows the variation of electric field across the p-n junction. The electric field is directed from the p-type side to the n-type side. The electric field is highest at the edges of the depletion region. The electric field is zero in the depletion region.

Formation of Graph

The potential, charge density, and electric field graphs are related to each other. The potential graph determines the charge density and the electric field. The charge density and electric field are related by the Poisson equation. The Poisson equation relates the charge density to the potential and the electric field to the potential gradient.

Conclusion

The potential, charge density, and electric field graphs are important in understanding the behavior of a p-n junction diode. The potential barrier, charge density, and electric field determine the behavior of the diode. The graphs show the variation of these parameters across the p-n junction. The graphs help in designing and analyzing p-n junction diodes.