In the presence of impurities or in a nonstoichiometric solid, free electrons or electron holes are produced as a result of “charge compensation” to neutralize the effect of charged ionic defects 。
在杂质存在的情况下,或在非化学计量比的固,和带电离子缺陷所引起的电荷不平衡,便会产生自由电子或电子空穴。