过渡金属Mn对SiC薄膜的结构和光学性能的影响

Influence of Manganese Doping on Microstructures and Optical Properties of SiC Films

采用射频磁控溅射的方法在Si衬底上制备了掺Mn的SiC薄膜,用X射线衍射、傅里叶变换红外光谱、扫描电镜及荧光光谱等方法,对薄膜的结构、表面形貌、化学键状态和光学性能进行了研究。结果表明:掺Mn使SiC晶格发生畸变,X射线衍射峰强度下降,Si-C键振动减弱;同时,由于掺Mn后提供了更多的Si空位复合发光中心,SiC薄膜在近带边414 nm处的室温光荧光峰增强为1.3倍。

Mn-doped SiC films were grown by radio frequency magnetron sputtering on silicon substrate. Its mi- crostructures and optical properties were characterized with X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Fourier transform infrared spectmscopy（FTIR） and ultraviolet fluorescence spectroscopy. The results show that Mn doping significantly affects the microstructures, chemical bonding, and optical properties of the SiC films. For exampie, as the Mn dopant concentration increases up to 15%, three features, including the lattice distortion, weakening of the SiC bond,and about 1.3 times intensity increase of photoluminescence emission（414nm）, were clearly observed at room temperature. Possible mechanism could be that Mn dopant produces increased Si vacancies.