Minoritetsbärarsor

Minoritetsbärarsor, which translates to "minority carrier" in English, refers to the charge carriers in a semiconductor that are in the minority within their respective energy bands. In intrinsic semiconductors, the number of electrons in the conduction band is equal to the number of holes in the valence band. However, when impurities are added to create extrinsic semiconductors, this balance is disrupted.

In an n-type semiconductor, which is doped with donor impurities, electrons are the majority carriers in the conduction band, and holes are the minority carriers. Conversely, in a p-type semiconductor, doped with acceptor impurities, holes are the majority carriers in the valence band, and electrons are the minority carriers.

The concentration of minority carriers is significantly lower than that of majority carriers. Despite their lower numbers, minority carriers play a crucial role in the operation of semiconductor devices. For instance, they are essential for recombination processes and are involved in the current flow across p-n junctions. Understanding and controlling minority carrier behavior is fundamental to designing and optimizing diodes, transistors, and other semiconductor components. The lifetime of minority carriers, which is the average time they exist before recombining with a majority carrier, is a critical parameter affecting device performance, particularly in devices like solar cells and photodetectors where the generation of electron-hole pairs is central to their function.