The depletion layer of a P-N junction diode is due to

The depletion layer of a P-N junction diode is due to doping of the materials and diffusion of charge carriers.

Important:

• Doping is the process of adding certain chemical elements to a semiconductor in order to change its electric conductivity.

• Depletion region is formed when two opposite type of semiconductors (p and n) are in contact
• Due to concentration difference of carriers (electrons in n-type and hole in p-type), the majority carriers cross the junction and recombine
• The movement of carriers across the junction creates a deficiency of carriers in the semiconductor

• Near the junction; Which is deficiency of electrons in the n region (generating positive charge) and deficiency of holes in p region (generating negative charge)

• The charges on both sides of the junction generate an electric field which prevents further diffusion of charge carriers