【摘要】 采用脉冲激光沉积技术在Si/蓝宝石衬底上制备了ZnO薄膜,结合快速退火设备研究了不同退火温度(500~900℃)及退火气氛(N2,O2)对薄膜的结构及其发光性能的影响。并优化条件得到具有最小半峰全宽及最大晶粒尺寸的薄膜。X射线衍射(XRD)结果表明:氮气氛下退火的ZnO薄膜最佳退火温度为900℃;氧气氛下退火的ZnO薄膜最佳退火温度为800℃。红外(IR)光谱中,退火后Zn-O特征振动峰红移,说明在退火过程中,原子重新排布后占据较低能量位置;同样的退火温度下,氮气氛下退火的薄膜质量更优。同步辐射光电子能谱(synchrotron-based XPS)分别表征了未退火及N2,O2下900℃退火的ZnO薄膜,分峰拟合结果表明氧气氛下退火产生更多的氧空位。结构表征结合光致发光(PL)谱表明绿光的发光峰与氧空位有关。更多还原

【Abstract】 Thin ZnO films were grown on silicon(111)/sapphire substrate via pulsed laser deposition technique and then some of the samples were treated with different rapid thermal annealing(RTA) conditions,such as annealing temperature ranging of 500 to 900 ℃ and annealing ambience(nitrogen and oxygen).Finally,these samples were characterized with X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),IR and photoluminescence(PL),respectively.It was observed that the quality and the grain size of thin ZnO films increased after annealing.Moreover,at the same lower annealing temperature,the films annealed under nitrogen ambience showed better qualities and few oxygen vacancies than those annealed under oxygen ambience.The experiment showed that the best annealing temperature under nitrogen ambience was 900 ℃ and the optimum annealing temperature under oxygen ambience was 800 ℃.Furthermore,as oxygen vacancies decreased,stronger green photoluminescence was detected,possibly related to the contents of the oxygen vacancies.更多还原