The role of surface activation prior to seeding on CVD diamond adhesion
The role of surface activation prior to seeding on CVD diamond adhesion
复制标题
DOI：
10.1016/j.surfcoat.2010.04.031
复制
发表时间：
2010-08
影响因子：
5.4
通讯作者：
M. Amaral;F. A. Almeida;A. Fernandes;F. Costa;F. Oliveira;Rui F. Silva
中科院分区：
文献类型：
--
作者：
M. Amaral;F. A. Almeida;A. Fernandes;F. Costa;F. Oliveira;Rui F. Silva
提出了一种特殊的表面预处理方案，包括四个步骤，以提供高附着力水平的CVD金刚石热丝技术。在步骤1中，用15µm金刚石浆料对氮化硅陶瓷基板进行表面研磨，并用胶体二氧化硅（0.05µm）进行镜面抛光。在步骤2中，使用CF 4（PE）的等离子体蚀刻，由于表面粗糙度增加而促进机械锚定。表面活化（SA）是接下来的步骤，其中衬底经受CVD金刚石生长条件短时间（30分钟），导致无定形碳层的沉积，该无定形碳层负责增强成核密度和金刚石在沉积的早期阶段的进一步生长。最后步骤4是在超声波浴中接种0.5-1µm金刚石粉末。结果表明，经过表面预处理的Si 3 N4陶瓷表面具有较高的成核密度，可形成均匀、连续的金刚石薄膜，金刚石薄膜的生长速率为ap. 1.5µmh−1。Brale尖端压痕测试证实，由此产生高度粘附的膜（在900 N下无分层）。
A special surface pre-treatment protocol consisting of four steps is proposed to provide high adhesion levels for CVD diamond by hot-filament technique. In step 1, the silicon nitride ceramic substrates are surface ground with 15µm diamond slurry and mirror-like polished with colloidal silica (0.05µm). In step 2, plasma etching with CF4(PE), mechanical anchoring is promoted due to the surface roughness increment. Surface activation (SA) is the following step, where the substrates are subjected to CVD diamond growth conditions for a short time (30min), leading to the deposition of an amorphous carbon layer responsible for enhancing the nucleation density and the further growth of diamond during early stages of deposition. The final step 4 is 0.5–1µm diamond powder seeding in an ultrasonic bath. The results show that the Si3N4ceramic surface modified by the surface pre-treatment protocol allowed a high nucleation density promoting a continuous and homogeneous film of equally sized diamond grains, at a growth rate of ap. 1.5µmh−1. Brale tip indentation tests confirmed that highly adherent films are thus produced (no delamination under 900N).