在石墨烯缓冲蓝宝石上快速增长的无应变
Yue Qi, Yunyu Wang1,2, Zhenqian Pang3,4
1Research and Development Center for Solid State Lighting , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China.
Journal of the American Chemical Society
|September 4, 2018
概括
石墨烯缓冲层通过减少缺陷和应变,显著改善了蓝宝石上的化 (AlN) 薄膜的生长. 这提高了发光二极管应用的AlN质量.
科学领域:
- 材料科学
- 纳米技术
- 半导体物理
背景情况:
- 蓝宝石基板通常用于化 (AlN) 薄膜生长.
- AlN和蓝宝石之间的格子和热膨胀不匹配导致高缺陷密度和应变.
- 石墨烯的独特特性为新的缓冲层应用提供了潜力.
研究的目的:
- 研究石墨烯作为蓝宝石上AlN膜生长的缓冲层的作用.
- 了解石墨烯如何影响AlN核化,生长速度和缺陷形成.
- 评估石墨烯对AlN/蓝宝石系统应变放松的影响.
主要方法:
- 薄型石墨烯薄膜被用作蓝宝石基板和成长中的AlN薄膜之间的中间层.
- 使用分析核化密度,生长率和脱位演变的技术来表征AlN膜的生长.
- 测量了AlN和蓝宝石的应变状态,以评估石墨烯中间层的影响.
主要成果:
- 石墨烯降低了AlN核的密度,但增加了个体核的生长率.
- 石墨烯的存在导致凝聚边界的线程位移减少.
- 石墨烯有效地适应了晶格和热膨胀不匹配,在AlN和蓝宝石中显著放松了应变.
- 应变放松导致AlN膜的整体缺陷密度较低.
结论:
- 石墨烯作为有效的缓冲层,显著提高了在蓝宝石上生长的AlN薄膜的质量.
- 该研究强调了石墨烯在减轻应变和减少缺陷方面的作用, 这对于高性能光电子设备至关重要.
- 这些发现为石墨烯在III化物生长和先进发光二极管的开发提供了宝贵的见解.
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