What is junction diode /semiconductor diode

 What is junction diode

It is a two electrode device made up semiconductors

Construction

A p-type semiconductor and a N- type

semiconductor are joined by growth

technique at the middle known as .

A substance indium is placed on  p-side or N-side and heated to 500k.on melting a

layer is formed.Another semiconductor of 

Opposite type is sandwitch and on cooling,

A junction is formed known as junction diode

Working/action

P-side has majority charge carriers holes.N-side has majority charge electrons. Normally at the junction electrons diffuse from p-side to N-side and holes diffuse from p-side to N-side holes cross to either side they oppose further flow of charge carriers.As a result a layer is formed near the junction in which p-side contains electrons and N-side contains holes is called depletion layer/potential barrier/contact potential. Due to depletion layer charge carriers do not move to either of the side and diode does not conduct.

A junction diode connect with an electric field works under two conditions

1- Forward biasing

2- Reverse biasing

Semiconductor 

With rise of temperature resistance of conductor increase and conductivity increases with rise of temperature. Therefore the semiconductor playes important role in electronics.most of electrons devices are made up of semiconductor