高温退火对非晶CN_x薄膜场发射特性的影响

The effect of annealing on the field emission properties of amorphous CN_x films

采用射频磁控溅射方法在纯N2 气氛中沉积了非晶CNx 薄膜样品 ,并在真空中退火至 90 0℃ .对高温退火引起的CNx 薄膜化学成分、键合结构及其场发射特性方面的变化进行研究 .用傅里叶变换红外光谱和x射线光电子能谱分析样品的内部成分及键合结构的变化 ,其中sp2 键及薄膜中N的含量与薄膜的场发射特性密切相关 .退火实验的结果表明高温退火可以导致CNx 薄膜中N含量大量损失 ,并在薄膜中形成大量sp2 键 ,这些化学成分及键合结构上的变化将直接影响CNx 薄膜的场发射特性 .与其他温度退火样品相比 ,75 0℃退火的样品具有最低的阈值电场 。

The carbon nitride films deposited by r.f. magnetron sputtering in pure N-2 discharge were annealed in vacuum up to 900 degreesC. The chemical composition and bonding structure of the films were studied using x-ray photoelectron spectroscopy, Fourier Transform Infrared. The effects of thermal annealing on the bonding structure and the electron field emission characteristics of CNx films were investigated. It is found that the sp(2) bonds and N content in CNx films are closely related to the filed emission of CNx films. The results show that thermal annealing treatment causes a great loss of N content and a larger formation of sp(2) bonds in CNx films, which would influence significantly the field emission properties for the CNx films. The CNx films annealed at 750 degreesC show the optimal electron emission properties. Besides, the correlation between the chemical bonding structures and electron emission properties for the CNx films was also discussed.