Yan Xuejun, Sun Maosong, Ji Jianli, He Zhuokun, Zhang Jicai, Sun Wenhong
Research Center for Optoelectronics Materials and Devices, School of Physical Science and Technology, Guangxi University, Nanning 530004, China.
College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 100029, China.
Materials (Basel). 2024 Jan 9;17(2):327. doi: 10.3390/ma17020327.
AlN epilayers were grown on magnetron-sputtered (MS) (11-22) AlN buffers on -plane sapphire substrates at 1450 °C via hydride vapour phase epitaxy (HVPE). The MS buffers were annealed at high temperatures of 1400-1600 °C. All the samples were characterised using X-ray diffraction, atomic force microscopy, scanning electron microscope and Raman spectrometry. The crystal quality of epilayers regrown by HVPE was improved significantly compared to that of the MS counterpart. With an increasing annealing temperature, the crystal quality of both MS buffers and AlN epilayers measured along [11-23] and [1-100] improved first and then decreased, maybe due to the decomposition of MS buffers, while the corresponding anisotropy along the two directions decreased first and then increased. The optimum quality of the AlN epilayer was obtained at the annealing temperature of around 1500 °C. In addition, it was found that the anisotropy for the epilayers decreased significantly compared to that of annealed MS buffers when the annealing temperature was below 1500 °C.
通过氢化物气相外延（HVPE）在1450℃下于 - 平面蓝宝石衬底上的磁控溅射（MS）（11 - 22）AlN缓冲层上生长AlN外延层。MS缓冲层在1400 - 1600℃的高温下进行退火。所有样品均使用X射线衍射、原子力显微镜、扫描电子显微镜和拉曼光谱进行表征。与MS对应物相比，通过HVPE再生长的外延层的晶体质量有显著提高。随着退火温度的升高，沿[11 - 23]和[1 - 100]测量的MS缓冲层和AlN外延层的晶体质量先提高后下降，这可能是由于MS缓冲层的分解，而沿两个方向的相应各向异性先降低后增加。在约1500℃的退火温度下获得了AlN外延层的最佳质量。此外，还发现当退火温度低于1500℃时，外延层的各向异性与退火后的MS缓冲层相比显著降低。
