High‐Brightness Blue Light‐Emitting Diodes Enabled by a Directly Grown Graphene Buffer Layer |
| |
| Authors: | Zhaolong Chen Xiang Zhang Zhipeng Dou Tongbo Wei Zhiqiang Liu Yue Qi Haina Ci Yunyu Wang Yang Li Hongliang Chang Jianchang Yan Shenyuan Yang Yanfeng Zhang Junxi Wang Peng Gao Jinmin Li Zhongfan Liu |
| |
| Affiliation: | 1. Center for Nanochemistry (CNC), Beijing Science and Engineering Center for Nanocarbons, College of Chemistry and Molecular Engineering, Peking University, Beijing, China;2. State Key Laboratory of Solid‐State Lighting, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China;3. Beijing Engineering Research Center for the 3rd Generation Semiconductor Materials and Application, Beijing, China;4. School of Microelectronics, University of Chinese Academy of Sciences, Beijing, China;5. Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, China;6. Key Laboratory for Micro‐/Nano‐Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha, China;7. State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China;8. Beijing Graphene Institute (BGI), Beijing, P. R. China;9. Collaborative Innovation Centre of Quantum Matter, Beijing, China |
| |
| Abstract: | Single‐crystalline GaN‐based light‐emitting diodes (LEDs) with high efficiency and long lifetime are the most promising solid‐state lighting source compared with conventional incandescent and fluorescent lamps. However, the lattice and thermal mismatch between GaN and sapphire substrate always induces high stress and high density of dislocations and thus degrades the performance of LEDs. Here, the growth of high‐quality GaN with low stress and a low density of dislocations on graphene (Gr) buffered sapphire substrate is reported for high‐brightness blue LEDs. Gr films are directly grown on sapphire substrate to avoid the tedious transfer process and GaN is grown by metal–organic chemical vapor deposition (MOCVD). The introduced Gr buffer layer greatly releases biaxial stress and reduces the density of dislocations in GaN film and InxGa1?xN/GaN multiple quantum well structures. The as‐fabricated LED devices therefore deliver much higher light output power compared to that on a bare sapphire substrate, which even outperforms the mature process derived counterpart. The GaN growth on Gr buffered sapphire only requires one‐step growth, which largely shortens the MOCVD growth time. This facile strategy may pave a new way for applications of Gr films and bring several disruptive technologies for epitaxial growth of GaN film and its applications in high‐brightness LEDs. |
| |
| Keywords: | chemical vapor deposition gallium nitride graphene light‐emitting diodes |
|
|
