ZnO薄膜中与Zn原子缺陷相关的发光特性研究

Luminescence properties of ZnO thin films related to Zn atomic defects

ZnO薄膜中可见光的发射与缺陷有关,为了研究ZnO薄膜中与Zn原子缺陷相关的发光特性,将不同Zn缓冲层厚度的ZnO薄膜沉积在Si衬底上,且所有样品在400℃下真空中退火1 h,采用X射线衍射谱(XRD)、吸收谱和光致发光谱(PL)表征了样品的晶体结构和光学特性。结果表明,随着Zn缓冲层溅射时间的增加,ZnO薄膜中的紫光峰向长波段发生了红移,且所有的发光峰强度逐渐增加;缓冲层和真空中退火都使得样品中有过量的Zn原子缺陷出现,薄膜中所有的发光峰与Zn原子缺陷相关。

Visible emission in ZnO thin films is related to defects. In this paper, in order to study the luminescent properties of ZnO thin films related to Zn atom defects, ZnO thin films with different thickness of Zn buffer layer were deposited on Si substrates, and annealed at 400 ℃ for 1 h. Crystal structure and optical properties were characterized by X-ray diffraction(XRD) patterns, absorption spectra and photoluminescence(PL) spectra. Results show that as the sputtering time of Zn buffer layer increased, the violet peak in ZnO thin films shifted towards longer wavelength, and the intensity of all emission peaks increased gradually. Based on experimental results, it could be concluded that both Zn buffer layer and annealing treatment made excessive Zn atom defects appeare in the samples, and all the emission peaks was related with Zn atom defects.