Zhang Shuo, Liu Bingyao, Ren Fang, Yin Yue, Wang Yunyu, Chen Zhaolong, Jiang Bei, Liu Bingzhi, Liu Zhetong, Sun Jingyu, Liang Meng, Yan Jianchang, Wei Tongbo, Yi Xiaoyan, Wang Junxi, Li Jinmin, Gao Peng, Liu Zhongfan, Liu Zhiqiang
Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
Small. 2021 May;17(19):e2100098. doi: 10.1002/smll.202100098. Epub 2021 Mar 31.
The nitride films with high indium (In) composition play a crucial role in the fabrication of In-rich InGaN-based optoelectronic devices. However, a major limitation is In incorporation requiring a low temperature during growth at the expense of nitride dissociation. Here, to overcome this limitation, a strain-modulated growth method, namely the graphene (Gr)-nanorod (NR) enhanced quasi-van der Waals epitaxy, is proposed to increase the In composition in InGaN alloy. The lattice transparency of Gr enables constraint of in-plane orientation of nitride film and epitaxial relationships at the heterointerface. The Gr interlayer together with NRs buffer layer substantially reduces the stress of the GaN film by 74.4%, from 0.9 to 0.23 GPa, and thus increases the In incorporation by 30.7%. The first principles calculations confirm that the release of strain accounts for the dramatic improvement. The photoluminescence peak of multiple quantum wells shifts from 461 to 497 nm and the functionally small-sized cyan light-emitting diodes of 7 × 9 mil are demonstrated. These findings provide an efficient approach for the growth of In-rich InGaN film and extend the applications of nitrides in advanced optoelectronic, photovoltaic, and thermoelectric devices.
高铟（In）组分的氮化物薄膜在富铟氮化铟镓基光电器件的制造中起着关键作用。然而，一个主要限制是铟的掺入需要在低温下进行，这是以氮化物分解为代价的。在此，为了克服这一限制，提出了一种应变调制生长方法，即石墨烯（Gr）-纳米棒（NR）增强准范德华外延，以提高氮化铟镓合金中的铟组分。石墨烯的晶格透明度能够限制氮化物薄膜的面内取向以及异质界面处的外延关系。Gr中间层与NRs缓冲层一起将氮化镓薄膜的应力从0.9 GPa大幅降低74.4%至0.23 GPa，从而使铟的掺入量增加30.7%。第一性原理计算证实应变的释放是显著改善的原因。多量子阱的光致发光峰从461 nm 移至497 nm，并展示了7×9密耳的功能型小尺寸蓝光发光二极管。这些发现为富铟氮化铟镓薄膜的生长提供了一种有效方法，并扩展了氮化物在先进光电器件、光伏器件和热电器件中的应用。
