C(膜)/Si(SiO2 )(纳米微粒)/C(膜)热处理的形态及结构分析

用直流辉光溅射+真空镀膜法制备了一种新型结构的硅基纳米发光材料- C(膜)/Si(SiO2)(纳米微粒)/C(膜)夹层膜,并对其进行了退火处理.用TEM、 SEM、 XRD和XPS对其进行了形态结构分析.TEM观察表明: Si(SiO2)纳米微粒基本呈球形,粒径在30 nm左右.SEM观察表明: 夹层膜样品总厚度约为50 μm,膜表面比较平整、致密.400℃退火后,样品表面变得凹凸不平,出现孔状结构; 650℃退火后,样品表面最平整、致密且颗粒均匀.XRD分析表明:制备出的夹层膜主要由SiO2和Si组成,在C原子的还原作用和氧气的氧化作用的共同作用下, SiO2和Si的含量随加热温度的升高而呈现交替变化: 400℃时, C的还原作用占主导地位, SiO2几乎全部被还原成了Si,此时Si含量最高; 400～650℃时,氧化作用占主导地位, Si又被氧化成SiO2, Si含量降低, SiO2含量逐渐上升,在650℃达到最高.XPS分析表明: 在加热过程中, C原子逐渐扩散进入Si(SiO2)微粒层,在650℃与Si反应生成了新的SiC.

The Configuration of Annealed C(Film)/Si (SiO2)(Nanometer Particles)/C(Film)

A new silicon-based luminescence material—C(film)/Si(SiO2)(nanometer particles)/C(film) has been prepared by sputtering Si(SiO2) nano-particles on amorphous carbon film in Argas, then depositing amorphous carbon film on Si(SiO2) nano-particles in vacuum. The sample consists of 6 layers of carbon films and 5 layers of Si(SiO2) nano-particles. Finally, the sample is annealed at different temperatures(RT-750℃). Its configuration has been studied by means of TEM, SEM, XRD and XPS. TEM image shows that Si(SiO2) nano-particles almost be spherical, whose diameter is about 30nm. SEM images show that the thickness of the sample is about 50μm and the surface of the sample is relatively flat and compact. Hole structure is found on the surface of sample annealed at 400℃, the particles on the surface are well-distributed and compacted after annealed at 650℃, particle aggregations grow after annealed 750℃. XRD spectra shows that the sample is almost composed by SiO2and Si, and the ratio of SiO2/Si alternately changes with the increase of annealing temperature: SiO2are reduced to Si by C atoms at 400℃, so the content of Si is highest, on the contrary, the content of SiO2is lowest. Si nanometer particles are oxidized superiorly beyond 400℃, so the content of Si gradually decreases, the content of SiO2 gradually increases and becomes to highest at 650℃. XPS spectra shows that C atoms diffuse into Si (SiO2) nano-particles layer during annealing, and produce SiC by reacting with Si at 650℃.