Aluminum nitride is a promising substrate material for AlGaN‐based UV‐LED. In order to develop a robust growth processing route for AlN single crystals, fundamental studies of solution growth experiments using Ni‐Al alloy melts as a new solution system were performed. Al can be stably kept in solution the Ni‐Al liquid even at high temperature; in addition, the driving force of the AlN formation reaction from solution can be controlled by solution composition and temperature. To investigate AlN crystal growth behavior we developed an in situ observation system using an electromagnetic levitation technique. AlN formation behavior, including nucleation and growth, was quantitatively analyzed by an image processing pipeline. The nucleation rate of AlN decreased with increasing growth temperature and decreasing aluminum composition. In addition, hexagonal c‐axis oriented AlN crystal successfully grew on the levitated Ni‐40 mol%Al droplet reacted at low driving force (1960 K), on the other hand, AlN crystal with dendritic morphology appeared on the sample with higher driving force (Ni‐50 mol%Al, 1960 K). Thus, the nucleation rate and crystal morphology were dominated by the driving force of the AlN formation reaction.

中文翻译：

---

使用电磁悬浮技术对Ni-Al溶液中AlN形成的原位观察

氮化铝是用于AlGaN基UV-LED的有前途的基材。为了为AlN单晶建立稳健的生长工艺路线，对使用Ni-Al合金熔体作为新溶液系统进行溶液生长实验的基础研究进行了研究。即使在高温下，也可以将Al稳定地保持在Ni-Al溶液中。另外，可以通过溶液组成和温度来控制由溶液形成AlN的反应的驱动力。为了研究AlN晶体的生长行为，我们开发了使用电磁悬浮技术的原位观察系统。通过图像处理管线对AlN的形成行为（包括成核和生长）进行了定量分析。AlN的成核速率随生长温度的升高和铝成分的降低而降低。此外，六方c轴取向的AlN晶体在低驱动力（1960 K）下反应的悬浮Ni‐40 mol％Al液滴上成功生长，另一方面，具有较高驱动力的样品上出现了具有树枝状形态的AlN晶体（Ni‐ 50 mol％Al，1960 K）。因此，成核速率和晶体形态受AlN形成反应的驱动力支配。