Nano-buffer controlled electron tunneling to regulate heterojunctional interface emission
纳米缓冲控制电子隧穿以调节异质结界面发射
ヘテロ接合界面放出を調節するためのナノバッファー制御電子トンネリング
이종 접합 계면 방출을 조절하기 위한 나노 버퍼 제어 전자 터널링
Túnel de electrones controlado por nano-búfer para regular la emisión de la interfaz heterouniónica
Tunnellisation électronique contrôlée par nano-tampon pour réguler l'émission d'interface hétérojonctionnelle
Электронное туннелирование, управляемое нанобуфером, для регулирования эмиссии гетероперехода
Wei Liu 刘威, Zhuxin Li 李竹新, Zengliang Shi 石增良, Ru Wang 王茹, Yizhi Zhu 朱益志, Chunxiang Xu 徐春祥
State Key Laboratory of Bioelectronics, School of Biological Sciences & Medical Engineering, Southeast University, Nanjing 210096, China
中国 南京 东南大学生物科学与医学工程学院 生物电子学国家重点实验室
Interface emission from heterojunction is a shortcoming for electroluminescent devices. A buffer layer introduced in the heterojunctional interfaces is a potential solution for the challenge. However, the dynamics for carrier tunneling to control the interface emission is still a mystery. Herein, the low-refractive HfO₂ with a proper energy band configuration is employed as the buffer layer in achieving ZnO-microwire/HfO₂/GaN heterojunctional light-emitting diodes (LEDs).
The optically pumped lasing threshold and lifetime of the ZnO microwire are reduced with the introduced HfO₂ layer. As a result, the interface emission is of blue-shift from visible wavelengths to 394 nm whereas the ultraviolet (UV) emission is enhanced. To regulate the interface recombination between electrons in the conduction band of ZnO and holes in the valence band of GaN, the tunneling electrons with higher conduction band are employed to produce a higher tunneling current through regulation of thin HfO₂ film causing blue shift and interface emission enhancement.
Our results provide a method to control the tunneling electrons in heterojunction for high-performance LEDs.
