Optoelectronic Simulations of InGaN-Based Green Micro-Resonant Cavity Light-Emitting Diodes with Staggered Multiple Quantum Wells
Tsau-Hua Hsieh,
Wei-Ta Huang,
Kuo-Bin Hong,
Tzu-Yi Lee,
Yi-Hong Bai,
Yi-Hua Pai,
Chang-Ching Tu,
Chun-Hui Huang,
Yiming Li,
Hao-Chung Kuo
Affiliations
Tsau-Hua Hsieh
Department of Electrical and Computer Engineering, Institute of Communications Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
Wei-Ta Huang
Department of Photonics, Institute of Electro-Optical Engineering, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
Kuo-Bin Hong
Semiconductor Research Center, Hon Hai Research Institute, Taipei 11492, Taiwan
Tzu-Yi Lee
Department of Photonics, Institute of Electro-Optical Engineering, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
Yi-Hong Bai
Department of Photonics, Institute of Electro-Optical Engineering, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
Yi-Hua Pai
Department of Photonics, Institute of Electro-Optical Engineering, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
Chang-Ching Tu
Semiconductor Research Center, Hon Hai Research Institute, Taipei 11492, Taiwan
Chun-Hui Huang
Technology Development Center, InnoLux Corporation, Hsinchu 35053, Taiwan
Yiming Li
Department of Electrical and Computer Engineering, Institute of Communications Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
Hao-Chung Kuo
Department of Photonics, Institute of Electro-Optical Engineering, College of Electrical and Computer Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
In this research, we compared the performance of commercial μ-LEDs and three-layered staggered QW μ-LED arrays. We also investigated the self-heating effect. We proposed a green micro-resonant cavity light-emitting diode (µ-RCLED) that consists of a three-layer staggered InGaN with multiple quantum wells (MQWs), a bottom layer of nanoporous n-GaN distributed Bragg reflectors (DBRs), and a top layer of Ta2O5/SiO2 DBRs. We systematically performed simulations of the proposed µ-RCLEDs. For the InGaN MQWs with an input current of 300 mA, the calculated wavefunction overlaps are 8.8% and 18.1% for the regular and staggered structures, respectively. Furthermore, the staggered MQWs can reduce the blue-shift of electroluminescence from 10.25 nm, obtained with regular MQWs, to 2.25 nm. Due to less blue-shift, the output power can be maintained even at a high input current. Conversely, by employing 6.5 pairs of Ta2O5/SiO2 DBRs stacks, the full width at half maximum (FWHM) can be significantly reduced from 40 nm, obtained with ordinary µ-LEDs, to 0.3 nm, and a divergence angle smaller than 60° can be obtained. Our simulation results suggest that the µ-RCLEDs can effectively resolve the wavelength instability and color purity issues of conventional µ-LEDs.
