用注射超声喷雾法将前驱体由针管直接送入超声喷头内, 在石英基板上制备Zn1-xCrxO（x=0.0, 0.01, 0.03, 0.05）薄膜。 采用X射线衍射仪、 扫描电子显微镜、 荧光光谱仪、 紫外-可见分光光度计、 振动样品磁强计（VSM）等对薄膜的结构、 光学和磁学性质进行测量。 实验结果表明, 未掺杂的ZnO薄膜为六角纤锌矿结构, 沿着c轴（002）择优取向, 而Cr掺杂抑制了薄膜的c轴择优取向性； 掺杂后的薄膜平均晶粒尺寸均增大, 且当x=3%时, 晶粒尺寸最大, 达31.4 nm。 扫描电镜（SEM）下薄膜呈球形颗粒状, 并且在x=5%下, 薄膜出现了长条状的微观形貌。 Cr掺杂使样品的光致发光谱（PL）发生了很大的变化： 未掺杂的样品的PL谱在378 nm处存在一个紫外发射峰, 对应于550 nm附近还存在一个由于缺陷态引起的绿光发射峰； 掺Cr样品只有在350～550 nm的很宽的范围内存在一个发射峰, 对其进行高斯拟合后, 发现掺Cr量为x=1％, 3％, 5％下样品均存在VZn（锌空位）、 Zni（Zn间隙位）、 V-Zn（带一个电子的锌空位）内部缺陷态, 且当x=3%时, VZn最多。 Cr的掺杂使得薄膜的带隙增大, 并且x=3%时, 禁带宽度最大, 达到3.374　eV。 掺Cr的三个样品均具有室温铁磁性, 且x=3%样品的磁化强度最大, 其与VZn(锌空位）最大相对应, 验证了Cr3+和VZn的缺陷复合体是ZnO∶Cr样品具有稳定的铁磁有序的最有利条件的理论预测。

The precursor solution is sent to the ultrasonic nozzle directly through a needle tube to prepare Zn1-xCrxO（x=0, 0.01, 0.03 and 0.05）films on quartz substratesby ultrasonic spray method.　The structures, optical and magnetic properties of the films were measured by X-ray diffracmeter(XRD), scanning electron microscope(SEM), fluorescence spectrometer, ultraviolet-visible light detector, vibrating　sample　magnetometer (VSM) and so on.　The experimental results indicate that, the undopedZnO thin films exhibit the hexagonal wurtzite crystalline structure with a preferential orientation of (002); the Cr doping restrains the preferred orientation of C axis; the average grain sizes of the samples increase withCr doping, and thesize attains the maximum(31.4 nm) when x=3%. The SEMimages show that the Zn1-xCrxO (x=0, 0.01, 0.03 and 0.05) films are grain-like particles. And it exhibits a long strip shape when x=5%. Moreover, the doping of Cr makes the photoluminescence (PL) spectra of Zn1-xCrxO films change evidently. The undoped sample shows an ultraviolet emission peak at 378 nm as well as a defect related green peak at around 550 nm. However, for the doping samples, there is only a wide range of emission peak from 350 to 550 nm. By gaussian fitting, it is found that VZn, Zni　and　V－Zn defects exist in the Cr doping films, and VZn is largest when x=3%. The band gap increases with the doping of Cr, and reaches the maximum when x=3%. The doping of Cr hasthe band gap of the samples increase, and the band gapreachs themaximum(3.37　eV) when x=3%. Magnetic measured results show that threedoping samples Zn1-xCrxO(x=1%, 3% and 5%) are ferromagnetic at room temperature, and the magnetization of Zn1-xCrxO (x=3%) is the largest, which is corresponding to the most VZn　defect. The experimental results also prove the the oretical prediction that the substitutive Cr in the oxidation state of +3 and the neutral Zn vacancy in the ZnO∶Cr sample are the most favorable defect complex to maintain a high stability of ferromagnetic order.