The term used in transistor design to indicate the primary current-movement process. For a PNP transistor, the holes constitute the chief current carriers.
The type of current carriers, free electrons or holes, of which a given semiconductor contains the most.
The conduction band electrons in an n-type material and the valence band holes in a p-type material. Produced by pentavalent impurities in n-type material and trivalent impurities in p-type material.