金刚石颗粒表面Cr金属化及薄膜间界面扩散反应的研究

运用直流磁控溅射法可在金刚石颗粒表面沉积150nm的金属Cr层.在超高真空条件下,经300-600℃的热退火处理,可促进Cr膜与金刚石基底间的界面扩散和反应.利用俄歇电子能谱研究了Cr/金刚石颗粒界面的结合状态,发现Cr与金刚石薄膜发生了强烈的界面扩散,Cr元素渗入金刚石层达90nm,并在界面上发生化学反应形成Cr的碳化物层.对界面扩散反应动力学的研究表明,Cr/金刚石界面扩散反应的表观活化能为38.4kJ/mol,界面扩散反应主要由碳的扩散过程控制.热处理温度越高,界面扩散及反应越显著,但不利于碳化物层生成的氧化反应速度也会有所增加,界面反应产物从Cr₂C₃转变为Cr₂C物种.延长热处理时间有利于金属碳化物的生成,同样导致界面反应产物从Cr₂C₃转变为Cr₂C物种.

The Metallization and Interface Reaction Between Diamond Particle and Cr Layer

A Cr layer with thickness of 150 nm was successfully deposited on the surface of diamond particles using DCmagnetron sputtering technique. The interface diffusion and reaction between Cr and diamond was promoted by annealing in the range from 300 ℃ to 600 ℃ in high vacuum. The Auger profile results showed that the width of interface layer was more than 90 nm. A Cr₂Ccarbide layer was formed after Cr/diamond annealed above 500 ℃. The formation of Cr₂Con the interface was confirmed by Auger line shapes. When the annealing temperature was below 500 ℃ and annealing time less than 4 h, Cr₂C₃ interface species was formed. Higher temperature and longer time resulted in Cr₂Cinterface species. The chemical reaction suggested that there was a strong chemical bond on the interface of Cr/diamond, which was one of the important factors for the high adhesion strength between metal and diamond. The interface diffusion and reaction was governed by the diffusion of carbon from diamond substrate. The activation energy of the interface diffusion reaction was 38.4 kJ/mol. The interface species varied with annealing temperature and time.