nc-Ge/SiO_2薄膜的光发射和光吸收研究

Study on Light Emission and Optical Absorption of Nanocrystallites Ge Embedded in SiO_2 Films

采用射频磁控反应溅射技术和后退火法制备了nc-Ge/SiO2薄膜材料。采用X射线衍射仪(XRD)对薄膜的微结构进行测试,随着退火温度的升高,衍射峰的半高宽减小,表明Ge纳米晶粒的平均尺寸逐渐增大,发现经过1 000℃退火后的薄膜具有三个明显的纳米锗衍射峰。薄膜的傅里叶红外吸收谱表明,随着退火温度的升高,薄膜的红外吸收增强。室温下,测量了不同温度退火下薄膜的光致发光谱,观察到了紫外光、紫光和橙色光。而且不同退火温度的薄膜,其光致发光谱有所不同,理论上着重讨论了紫光和橙光的发光机制。

The nc-Ge/SiO2 compound films were prepared by RF magnetron sputtering technique and annealing treatment,and the microstructures of the films were determined by the X-ray diffraction.With the increase of the annealing temperature,the full width at half-maximum of X-ray diffraction band peak decreased,which means that the average size of nc-Ge increased.The film annealed at 1 000 ℃ has three obvious crystalline diffraction peaks.The Fourier transform infrared absorption（FTIR）results of the films suggest that the infrared absorption increases with the annealing temperature increasing.The photoluminescence spectra of the films annealed at different temperatures were measured,and the ultraviolet,violet and orange luminescence were observed at room temperature.The luminescence mechanism of the violet and orange light was emphatically discussed in theory.