采用溶胶-凝胶方法,在6H-SiC衬底上制备ZnO薄膜。X射线衍射结果表明薄膜是C轴取向的,具有六方纤锌矿多晶结构。研究了退火温度对ZnO薄膜发光特性的影响。发现在650℃退火温度下,观察到近带边紫外发射和可见光发射并且紫外发光强度大于可见光发射。随着退火温度的提高,紫外峰强度减弱直至消失,而绿光发射强度先增加而后降低。对退火温度引起ZnO薄膜发光性质改变的机制进行了探讨。
ZnO films were grown on 6H-SiC substrates by a Sol-gel process. X-ray diffraction (XRD) shows that ZnO thin films have a polycrystalline hexagonal wurtzite structure with a c axis orientation. The influence of annealing temperature on room temperature photoluminescence (RTPL) of ZnO films was investigated. A 383nm near band edge (NBE) ultraviolet emission and a broad visible peak emission were observed at the annealing temperature of 650℃. The intensity of ultraviolet emission peak initially decreases and then disappears with the increase of annealing temperature, while the strength of visible emission initially increases and then decreases. The mechanism of annealing temperature on the RTPL of ZnO films was discussed.