2.Impurity defects(杂质缺陷) Defects caused by incorporation of impurity into the crystal Si 活动电子 Movable electrons 正电空穴 Positively charged vacancy Electron-excess Electron-deficient 2. Impurity defects (杂质缺陷 ) Electron-excess Electron-deficient Positively charged vacancy Movable electrons Defects caused by incorporation of impurity into the crystal