| Title | High-temperature annealing induced evolution of strain in AlN epitaxial films grown on sapphire substrates |
| Authors | Wang, M. X. Xu, F. J. Xie, N. Sun, Y. H. Liu, B. Y. Ge, W. K. Kang, X. N. Qin, Z. X. Yang, X. L. Wang, X. Q. Shen, B. |
| Affiliation | Peking Univ, Sch Phys, State Key Lab Artificial Microstruct & Mesoscop P, Beijing 100871, Peoples R China Collaborat Innovat Ctr Quantum Matter, Beijing 100871, Peoples R China |
| Issue Date | 2019 |
| Publisher | APPLIED PHYSICS LETTERS |
| Abstract | High-temperature (HT) annealing effects on the evolution of strain in AlN films grown on sapphire have been investigated. It is found that there is a significant transition behavior from tensile to compressive strain in AlN before and after HT annealing at an optimal temperature of 1700 degrees C. Based on a microstructural analysis, it is clarified that the HT annealing will result in the (1) disappearance of grains that account for the tensile stress before HT annealing, (2) generation of a new interface that has little influence on the lattice constant upper/below this interface, and (3) regular 8/9 arrangement of misfit dislocation at the AlN/sapphire interface that relieves almost all stress associated with lattice mismatch. It is thus deduced that the remnant compressive strain in AlN after HT annealing mainly comes from the cooling down process due to thermal mismatch between sapphire and AlN. This understanding of the annealing effect is certainly of great significance in AlN materials science and technology. Published under license by AIP Publishing. |
| URI | http://hdl.handle.net/20.500.11897/549873 |
| ISSN | 0003-6951 |
| DOI | 10.1063/1.5087547 |
| Indexed | SCI(E) EI |
| Appears in Collections: | 物理学院 人工微结构和介观物理国家重点实验室 |
