Controlled concentrations of specific donors or acceptors may be intentionally added into materials to form extrinsic semiconductor using various techniques . such an alloying process in semiconducting materials is termed doping 控制特定施主和受主原子的浓度，进而运用各种方法能动地填加，这种在半导体材料中加入合金成分的过程称为掺杂。
