Microstructures of dome-shaped hillocks formed on B doped CVD homoepitaxial diamond films
Microstructures of dome-shaped hillocks formed on B doped CVD homoepitaxial diamond films
复制标题
DOI：
10.1016/j.diamond.2019.05.008
复制
发表时间：
2019-08-01
影响因子：
4.1
通讯作者：
Makino, Toshiharu
中科院分区：
文献类型：
--
作者：
Tsubouchi, Nobuteru;Ogura, Masahiko;Makino, Toshiharu
在化学气相沉积（CVD）同外延金刚石薄膜的生长过程中，经常会产生各种有害的生长缺陷，降低晶体质量。其中，本研究主要利用透射电镜（TEM）对圆顶小丘（DH）的微观结构进行了详细的研究。TEM图像和选定区域的电子衍射图表明，DH内部由单晶（单畴）金刚石组成，其晶体学方向与薄膜或衬底相同。然而，在DHs的内部区域，存在许多位错，这些位错大多发生在膜与DH之间的边界区域附近，并延伸到DH内部。在所选区域的电子衍射图中，在沿[111]方向的基本反射中，在1/3和2/3位置观察到额外的衍射斑点，表明边界区域由具有共同{111}面的亲本和孪晶的杂化结构组成。还发现，在DHs底部的衬底与薄膜之间的界面周围存在直径为亚μ m的颗粒，这强烈表明DHs是由界面周围的颗粒成核的。
Various types of harmful growth defects lowering crystal quality are often produced during growth of chemical vapor deposition (CVD) homoepitaxial diamond films. Among these, in this study, microstructures of the dome-shaped hillock (DH) have been studied in details mainly using cross-sectional transmission electron microscopy (TEM). TEM images and selected area electron diffraction patterns indicated that the internal of the DH is composed of single crystal (single domain) diamond whose crystallographic direction is the same as that of the film or the substrate. However, in the internal area of the DHs, there are many dislocations, most of which occur near the boundary regions between the film and the DH and extend to the inside of the DH. In the boundary regions, extra diffraction spots at 1/3 and 2/3 positions in fundamental reflections along [111] directions were observed in the selected area electron diffraction patterns, demonstrating that the boundary regions consist of hybrid structures of parents and twins with common {111} planes. It was also been found that particles (sub mu m in diameter) exist around the interface between the substrate and the film at the bottom of the DHs, strongly suggesting that the DHs nucleate from the particles around the interface.