AlN gradient interlayer design for the growth of high-quality AlN epitaxial film on sputtered AlN/sapphire substrate
AlN gradient interlayer design for the growth of high-quality AlN epitaxial film on sputtered AlN/sapphire substrate
复制标题
用于在溅射 AlN/蓝宝石衬底上生长高质量 AlN 外延薄膜的 AlN 梯度夹层设计
DOI：
10.1039/c8ce01185k
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发表时间：
2018-11-07
期刊：
影响因子：
3.1
通讯作者：
Li, Xiangyang
中科院分区：
文献类型：
--
作者：
Tan, Bo;Hu, Jiahui;Li, Xiangyang
In this study, we proposed a novel method to grow high-quality AlN films on sputtered AlN/sapphire substrates by designing an AlN gradient interlayer (GIL-AlN). The epitaxial growth kinetics and growth mechanism were studied in detail, which are responsible for the effects of GIL-AlN layers on the morphology evolution, crystal quality and in-plane biaxial stress of AlN films by varying temperature and/or V/III ratio gradient. The results showed that the insertion of a temperature and V/III ratio gradient GIL-AlN promoted the initial coalescence of small sputtered AlN grains, which finally grew into larger and low-density AlN islands in consistent c-axis orientation, leading to less threading dislocations and biaxial tensile stress in the upper HT-AlN films. Finally, we obtained a 1.5 μm high-quality crack-free AlN film with an atomically smooth surface, and the full width at half-maximum values of (0002) and (102) rocking curves were 197 and 435 arcsec, respectively, in an almost stress-free state. This GIL-AlN method provides a possible way to improve the surface cracks and quality of AlN films deposited on sputtered AlN/sapphire substrates, which hold great promise for commercialization in AlN-based devices.
