In the formation of a p-n junction diode, arrange the following proce…

The correct answer is Option (3) → (C), (A), (D), (B)

Each step makes the next one possible, so the order follows the cause and effect in the junction.

(C) Doping comes first: the p-side and n-side are made by adding acceptor and donor impurities, which gives holes on one side and electrons on the other.

(A) Diffusion of charge carriers comes next: electrons from the n-side and holes from the p-side move across the junction because of the concentration difference.

(D) Generation of electric field at the junction follows: the fixed, uncovered donor and acceptor ions on the two sides of the junction set up a depletion layer with an electric field.

(B) Drift of charge carriers comes last: this field pushes carriers back in the direction opposite to diffusion, and in equilibrium the drift and diffusion currents balance.

The order is (C), (A), (D), (B).

NCERT (2026-27):
p-n Junction Formation – “Consider a thin p-type silicon (p-Si) semiconductor wafer. By adding precisely a small quantity of pentavelent impurity, part of the p-Si wafer can be converted into n-Si.”

p-n Junction Formation – “… During the formation of p-n junction, and due to the concentration gradient across p-, and n- sides, holes diffuse from p-side to n-side (p → n) and electrons diffuse from n-side to p-side (n → p).”

p-n Junction Formation – “… Due to the positive space-charge region on n-side of the junction and negative space charge region on p-side of the junction, an electric field directed from positive charge towards negative charge develops. … The motion of charge carriers due to the electric field is called drift.”