Growth and Characteristics of Epitaxial Al<sub>x</sub>Ga<sub>1−x</sub>N by MOCVD
Zhang Jie; Guo Li-Wei; Chen Yao; Xu Pei-Qiang; Ding Guo-Jian; Peng Ming-Zeng; Jia Hai-Qiang; Zhou Jun-Ming; Chen Hong; Zhang Jie; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Guo Li-Wei; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Chen Yao; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Xu Pei-Qiang; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Ding Guo-Jian; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Peng Ming-Zeng; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Jia Hai-Qiang; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Zhou Jun-Ming; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190; Chen Hong; Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190
Журнал:
Chinese Physics Letters
Дата:
2009-06-01
Аннотация:
Al<sub>x</sub>Ga<sub>1-x</sub>N epilayers with a wide Al composition range (0.2 ≤ x ≤ 0.68) were grown on AlN/sapphire templates by low-pressure metalorganic chemical vapour deposition (LP-MOCVD). X-ray diffraction results reveal that both the (0002) and (101̅5) full widths at half-maximum (FWHM) of the Al<sub>x</sub>Ga<sub>1−x</sub>N epilayer decrease with increasing Al composition due to the smaller lattice mismatch to the AlN template. However, the surface morphology becomes rougher with increasing Al composition due to the weak migration ability of Al atoms. Low temperature photoluminescence (PL) spectra show pronounced near band edge (NBE) emission and the NBE FWHM becomes broader with increasing Al composition mainly caused by alloy disorder. Meanwhile, possible causes of the low energy peaks in the PL spectra are discussed.
1.178Мб