Lany Stephan, Zunger Alex
National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
Phys Rev Lett. 2007 Jan 26;98(4):045501. doi: 10.1103/PhysRevLett.98.045501. Epub 2007 Jan 23.
Existing defect models for In(2)O(3) and ZnO are inconclusive about the origin of conductivity, nonstoichiometry, and coloration. We apply systematic corrections to first-principles calculated formation energies Delta H, and validate our theoretical defect model against measured defect and carrier densities. We find that (i) intrinsic acceptors ("electron killers") have a high Delta H explaining high n-dopability, (ii) intrinsic donors ("electron producers") have either a high Delta H or deep levels, and do not cause equilibrium-stable conductivity, (iii) the O vacancy V(O) has a low Delta H leading to O deficiency, and (iv) V(O) has a metastable shallow state, explaining the paradoxical coexistence of coloration and conductivity.
现有的氧化铟（In₂O₃）和氧化锌（ZnO）缺陷模型对于其导电性、非化学计量比和着色的起源尚无定论。我们对第一性原理计算的形成能ΔH进行了系统校正，并根据测量的缺陷和载流子密度验证了我们的理论缺陷模型。我们发现：（i）本征受主（“电子杀手”）具有较高的ΔH，这解释了高n型掺杂能力；（ii）本征施主（“电子产生者”）要么具有较高的ΔH，要么具有深能级，且不会导致平衡稳定的导电性；（iii）氧空位V（O）具有较低的ΔH，导致氧缺乏；（iv）V（O）具有亚稳浅能级状态，解释了着色与导电性自相矛盾的共存现象。
