During the formation of a p-n junction, an electric field is established across the depletion region

Question

During the formation of a p-n junction, an electric field is established across the depletion region. The direction of this built-in electric field is:

Professor PC Thomas Classes · Answer

The n-side loses electrons to become positively charged (uncovered donor ions), and the p-side loses holes to become negatively charged (uncovered acceptor ions). Hence, the electric field is directed from positive (n-side) to negative (p-side).