Question

Overall charge neutrality must be maintained in a semiconductor. What does this imply about Δp and Δn ?

A. they must change over time
B. they must equal zero
C. they must remain contant
D. they must equal each other

Answer 1

Overall charge neutrality in a semiconductor requires that the change in the number of holes must be equal to the change in the number of electrons, according to the law of conservation of charge.

Step-by-step explanation:

The overall charge neutrality in a semiconductor implies that the change in the number of holes (Δp) must be equal to the change in the number of electrons (Δn). This is due to the law of conservation of charge, which states that the electric charge cannot be created or destroyed in an isolated system. In practice, when a hole (absence of an electron) is created in a semiconductor, an electron is also created, maintaining charge neutrality. Therefore, Δp and Δn must equal each other (option D).