《不列颠百科全书》：
p-n junction
P-n junction, in electronics, the interface within diodes, transistors, and other semiconductor devices between two different types of materials called p-type and n-type semiconductors. These materials are formed by the deliberate addition of impurities to pure semiconductor materials, such as silicon. Semiconductors of p-type contain holes, mobile vacancies in the electronic structure that simulate positively charged particles, whereas n-type semiconductors contain free electrons. Electric current flows more easily across such a junction in one direction than in the other.
