间歇生长模式高甲烷浓度制备纳米金刚石膜

Preparation of Nanocrystalline Diamond Film at High Methane Concentration by the Intermittent Growing Mode

采用直流热阴极PCVD技术,经过生长温度的周期性调整,达到清除多余游离碳和刻蚀非金刚石相的目的,实现了在高甲烷浓度条件下制备纳米金刚石膜。金刚石膜的生长过程分为沉积阶段和刻蚀去除阶段,沉积时间为15min,刻蚀时间为5min,生长周期为20min,总的沉积时间为6h。采用拉曼光谱仪、SEM和XRD分析仪对样品进行了分析,结果显示样品具有纳米金刚石膜的基本特征。研究表明,在高甲烷浓度条件下,直流热阴极PCVD间歇生长模式可有效去除生长腔内的游离碳成分,实现正常放电激励,维持正常生长,制备出纳米金刚石膜。

The growth temperature is periodically adjusted in order to clear the redundant dissociation carbon and to etch the amorphous carbon on the surface of diamond film using DC hot-cathode plasma chemical vapor deposition（PCVD）. By this way, the nanocrystalline diamond films are prepared under the high methane concentration. Periodic growth process of diamond film is divided into two steps, deposition process and etching process, it alternates between deposition process and etching process. The time of deposition step is 15 minutes, etching step time is 5 minutes, a cycle time is 20 minutes. SEM, Raman spectroscopy and XRD analysis are used to characterize the diamond film samples. The results reveal that in the intermittent growing mode, the diamond film samples have the ＂characteristics of nanocrystalline diamond films. The conclusion is that using DC hot-cathode plasma CVD intermittent deposition mode, the redundant dissociation carbon can be cleared effectively, the glow discharge becomes normal, and nanocrystalline diamond films can be prepared.