Document Type
Article
Publication Date
12-14-2019
Abstract
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.
Keywords
aluminum nitride, crystal growth, nucleation, thermodynamics
Publication Title
Journal of the American Ceramic Society
Grant
JP26249113; JP26706013; JP17K19067; 1152716
Funder
Japan Society for the Promotion of Science; National Science Foundation (NSF)
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Loach, Andrew J.; Fada, Justin S.; Wilson, Laura G.; French, Roger H.; and Carter, Jennifer L. W., "In-situ Observation of AlN Formation from Ni-Al Solution Using an Electromagnetic Levitation Technique" (2019). Faculty Scholarship. 40.
https://commons.case.edu/facultyworks/40