超纳米金刚石薄膜场发射特性的研究

Field Emission Properties of Ultrananocrystalline Diamond Thin Films

超纳米金刚石(UNCD)是一种全新的纳米材料,具有许多独特性能。介绍了Si微尖和微尖阵列阴极沉积超纳米金刚石薄膜的工艺及其场发射特性。研究发现,适当的成核工艺和微波等离子体化学气相沉积工艺可在Si微尖上沉积一层光滑敷形的金刚石薄膜;沉积后阴极的电压 电流特性、发射电流的稳定性以及工作在氧气环境下的发射特性都获得明显提高。讨论了超纳米晶金刚石薄膜阴极的发射机理。

Ultrananocrystalline diamond (UNCD) is a type of nano-material with a number of unique pro-perties. This paper presents a process for depositing nanocrystalline diamond thin films on Si micro-tips and micro-tip arrays, and the field emission properties of the coated cathodes. With proper processing conditions, the coated UNCD thin films are extremely smooth and conformal to the shape of Si tips. For the coated Si micro-tip cathodes, the current-voltage characteristics, the stability of emission current and the emission properties in oxygen environment are substantially improved compared to the uncoated ones. The emission mechanism of UNCD is discussed.