溅射法制备的ZnO薄膜的光发射

报道了用射频磁控溅射法在硅衬底上制备出具有好的(002)择优取向的多晶ZnO薄膜，在514nm处观察到显著的单色绿光发射峰；且随着氧分压的增加，绿光发射峰的强度减弱．经真空中退火该发射峰增强；而在氧气中退火该发射峰强度减弱．该发射峰强度依赖于氧分压的事实表明：514nm绿光发射峰与ZnO薄膜中的氧空位缺密切相关，认为它来自于氧空位缺陷深施主能级上的电子到价带顶上的跃迁．

Photoluminescence of ZnO films prepared by sputtering

Highly orientated polycrystalline ZnO films with hexagonal structure have been successfully deposited on Si substrate at room temperature (RT) by sputtering system. The XRD spectra revealed that all samples were polycrystalline and had a preferred orientation with c-axis perpendicular to the substrates. Strong monochromatic green emission located at 514?nm has been observed when excited with 320?nm light at room temperature (RT). The green emission intensity decreases quickly with increasing oxygen pressure during film deposition and it increases markedly by thermal annealing in vacuum. On the contrary,for the samples annealed in oxygen,the PL intensity decreases. The green emission may correspond to the electron transition from deep oxygen vacancy level to the valance band.