What is p-n junction diode ? Define depletion layer.

In a PN -junction diode

In a p-n junction diode having depletion layer of thickness 10^(-6)m , the potential across it is 0.1V . The electric field produced is

In a p-n junction diode having depletion layer of thickness 10^(-6)m , the potential across it is 1V . The electric field produced is

p-n junction diode can be used as

(a) Explain with the help of suitable diagram , the two processes which occur during the formations of a p -n junction diode . Hence , define the terms : (i) depletion region and (ii) potential barrier : (b) Draw a circuit diagram of a p - n junction diode under forward bias and explain its working .

In p-n junction diode, near junction holes combine with electrons, and impurity ions form a barrier potential which opposes the recombination of electron-hole pairs. Value of barriers potential for Si is 0.7 volt and for Ge is 0.3 V. thus charge density at the junction becomes zero and an electric field is produced near junction. this region is called depletion layer. Thickness of depletion layer is of the order of 10^(-6) meter. in forward bias p terminal is connected with the positive terminal of cell and n is connected with negative terminal of cell and n is connected with negative terminal of cell. as forward voltage is increased, current increases exponentially. For Si diode minimum required forward voltage so that current can flow is

In p-n junction diode, near junction holes combine with electrons, and impurity ions form a barrier potential which opposes the recombination of electron-hole pairs. Value of barriers potential for Si is 0.7 volt and for Ge is 0.3 V. thus charge density at the junction becomes zero and an electric field is produced near junction. this region is called depletion layer. Thickness of depletion layer is of the order of 10^(-6) meter. in forward bias p terminal is connected with the positive terminal of cell and n is connected with negative terminal of cell and n is connected with negative terminal of cell. as forward voltage is increased, current increases exponentially. Correct graph for variation of charge density with distance from the junction is

The P-N junction is-

Explain the two processes involved in the formation of a p-n junction diode. Hence, define the term 'barrier potential'.

In junction diode, the holes are due to