What best characterizes P-type semiconductors?

P-type semiconductors are characterized by having holes as the majority carriers. In a P-type semiconductor, impurities are added to a pure semiconductor material (such as silicon) to create an excess of positively charged holes, which are essentially the absence of electrons. When trivalent atoms, such as boron, are introduced into the silicon lattice, they create these holes by accepting electrons from neighboring silicon atoms. This results in a situation where the movement of holes, or the absence of electrons, facilitates electrical conduction.

The majority carriers in P-type semiconductors are thus these holes, and they play a crucial role in the flow of electrical current. When a voltage is applied, these holes move towards the negative terminal, contributing to the overall conductivity of the material. This behavior is fundamental in devices like diodes and transistors, which rely on the movement of holes for their operation.