复合金刚石薄膜的介电特性

利用热丝大面积金刚石薄膜气相合成（CVD）装备制备了复合金刚石薄膜，并对其表面和断面分别进行了扫描电镜（SEM），原子力显微镜（AFM）和Raman光谱表征，研究了该复合结构的介电性能，利用共振电路测量了高频下薄膜的介质损耗与频率的关系，结果表明，复合结构由普通多晶金刚石薄膜和纳米金刚石薄膜组成，薄膜的表层结构体现了纳 米金刚石的特征，复合金刚石薄膜不仅具有表面光滑的优点，介电性能也接近于常规的多晶金刚石薄膜，是一种较好的电子材料，可应用于金刚石薄膜半导体器件的制备。

Dielectric Properties of Composite Diamond Films

The composite diamond films were prepared using a hot filament chemical vapor deposition reactor. The morphology and structure of the composite films were evaluated using scanning electron microscopy (SEM), atomic force microscopy (AFM) and Raman spectroscopy. The result shows that the composite film consists of conventional polycrystalline diamond layers and nanocrystalline diamond layers. The field dependence of the conduction and the frequency dependence of the dielectric loss in the composite diamond films were studied. The result shows that the surface of composite film is very smooth, and the dielectric properties are close to the conventional polycrystalline diamond films. It possesses superior pro perties of the conventional and nanocystalline diamond films, and can be applied to the fabrication of diamond semiconductor devices.