热氧化法制备的ZnO薄膜的光致发光特性研究

Photoluminescence Characteristics of ZnO Films Prepared by Thermal Oxidation

在空气中利用热氧化方法分别在P型硅、高阻硅、陶瓷以及N型硅衬底上制备了氧化锌(ZnO)薄膜.同时在氧气中、P型硅衬底上氧化制备少量氧化锌薄膜加以比较.氧化时间固定为1 h,氧化温度300℃～800℃.采用X射线衍射(XRD)以及光致发光(PL)光谱研究比较薄膜的结构和PL特性.发现在氧气中氧化样品质量明显好于在空气中氧化的样品.氧气中300℃氧化时有最窄的半高宽和最大的晶粒尺寸.在高阻硅材料衬底上制备的ZnO薄膜表现出较好的紫外发射带,而在陶瓷材料上表现出较好的绿色发射带.而N型材料也是较好的紫外发射材料,P型材料在低温下表现出较好的发光特性.

ZnO thin films were fabricated on the P-Si,high resistivity Si,ceramic and N-Si substrates by thermal oxidation in air. The oxidation time was fixed to 1 h at 300 ℃～800 ℃. The effects of different substrates such as the P-Si （111）, the high resistivity Si, the ceramics substrates and the N-Si are investigated. To obtain high-quality ZnO films, some Zn films are also annealed in the oxygen. It is found that the ZnO films prepared on the high resistivity Si substrates exhibit the better exeitonie ultraviolet （UV） emission,the ceramics substrates exhibit the better deep level visible emission. The ZnO films annealed in oxygen exhibit much better quality than that annealed in air.