Influence of the TEGa flow on the optical and structural properties of InGaN/GaN multiple quantum wells grown by MOCVD

✍ Scribed by Shanjin Huang; Bingfeng Fan; Yulun Xian; Zhiyuan Zheng; Zhisheng Wu; Hao Jiang; Gang Wang

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 789 KB
• Volume: 314
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2010.11.065

✦ Synopsis

We have investigated the influence of the TEGa flow on the optical and structural properties of InGaN/GaN multiple quantum wells (MQWs) with an indium composition around 20%. The samples with five-pairs InGaN/GaN MQWs were grown on sapphire substrates by metalorganic chemical vapor deposition. Photoluminescence spectra at 8 K showed that the MQWs grown with a low amount of TEGa flow gave a strong single peak and a higher emission energy. High-resolution X-ray diffraction measurements showed a deterioration of the InGaN/GaN interfaces in the sample grown with the large TEGa flow. The luminescence thermal quenching characteristics suggested that more structural defects acting as non-radiative recombination centers formed in the MQWs when the TEGa flow increased. The results indicate that decreasing the TEGa flow help to build up a new growth balance during the growth of InGaN wells, leading to less structural defects, more homogeneous indium distribution and the abrupt MQWs interfaces.