Results 191 to 200 of about 8,247 (230)

IQE and EQE of the nitride-based UV/DUV LEDs

CLEO:2011 - Laser Applications to Photonic Applications, 2011
Internal and external quantum efficiency and injection efficiency of nitride-based UV/DUV devices were investigated. Non radiative component in the photoluminescence and electroluminescence is found to be strongly correlated with the dislocation density.
H. Amano, G.J. Park, T. Tanikawa, Y. Honda, M. Yamaguchi, K. Ban, K. Nagata, K. Nonaka, K. Takeda, M. Iwaya, T. Takeuchi, S. Kamiyama, I. Akasaki   +12 more
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Development for long lifetime and high efficiency DUV LEDs

Gallium Nitride Materials and Devices XX
Yoshiki Saito, Atsushi Miyazaki, Shinya Boyama, Koji Okuno, Masaki Oya, Keita Kataoka, Tetsuo Narita, Kayo Horibuchi, Maki Kushimoto, Yoshio Honda, Hiroshi Amano, Hisanori Ishiguro, Tetsuya Takeuchi, Kohei Shima, Shigefusa F. Chichibu   +14 more
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Thermal Management for DUV LEDs

2019
DUV LEDs possess very huge heating issue. On one hand, the sapphire substrate has a poor thermal conductivity, and on the other hand, DUV photons are easily absorbed by the absorptive p-GaN layer and the metal contact in the way of free carrier absorption, which further increases the self-heating effect for DUV LEDs.
Zi-Hui Zhang, Chunshuang Chu, Kangkai Tian, Yonghui Zhang   +3 more
openaire   +1 more source

Improve the Current Spreading for DUV LEDs

2019
After the crystalline quality for Al-rich AlGaN layer is significantly improved, it is then the time to design novel DUV LED structures. DUV LEDs are driven electrically which get carrier transport and current injection involved. One of the challenges is the current crowding effect, which easily occurs in the DUV LEDs.
Zi-Hui Zhang, Chunshuang Chu, Kangkai Tian, Yonghui Zhang   +3 more
openaire   +1 more source

The Light Extraction Efficiency for DUV LEDs

2019
DUV LEDs have very low light extraction efficiency (LEE), which is caused by the unique optical polarization and the optically absorptive semiconductor and metal layers. This chapter reviews and analyzes the approaches that have ever been used to improve the LEE.
Zi-Hui Zhang, Chunshuang Chu, Kangkai Tian, Yonghui Zhang   +3 more
openaire   +1 more source

Enhance the Electron Injection Efficiency for DUV LEDs

2019
The unbalanced carrier injection for DUV LEDs illustrates that the electron tends to overflow from the active region. The underly mechanism arises from three aspects: (1) electrons cannot be consumed by forming electron-hole pairs and recombine radiatively in the active region, which is due to the insufficient hole injection, (2) the electron have ...
Zi-Hui Zhang, Chunshuang Chu, Kangkai Tian, Yonghui Zhang   +3 more
openaire   +1 more source

On the impact of a metal–insulator–semiconductor structured n-electrode for AlGaN-based DUV LEDs

Applied Optics, 2021
In this work, a 280 nm AlGaN-based deep ultraviolet light-emitting diode (DUV LED) with a metal–insulator–semiconductor (MIS) structured n-electrode is fabricated and studied. The S i O 2 insulator layer is adopted to form the MIS structure by using an atomic layer deposition system.
Hua Shao, Jiamang Che, Chunshuang Chu, Kangkai Tian, Yonghui Zhang, Xiaowei Sun, Zi-Hui Zhang   +6 more
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Improve the Hole Injection to Enhance the IQE for DUV LEDs

2019
The very low doping efficiency for the p-type Al-rich AlGaN layers indicates that the hole injection capability for DUV LEDs can be poor. Therefore, we ought to investigate the approaches to enable high-efficiency hole injection. In this chapter, we propose novel DUV LED architectures to make “hot” holes, increase the hole concentration in the p-type ...
Zi-Hui Zhang, Chunshuang Chu, Kangkai Tian, Yonghui Zhang   +3 more
openaire   +1 more source

Investigation on thermal characteristics and fabrication of DUV-LEDs using copper filled thermal hole

2017 18th International Conference on Electronic Packaging Technology (ICEPT), 2017
For deep ultraviolet light emitting diodes (DUV-LEDs) packaging, the choice of substrate directly affected its performance and reliability. In this paper, a structure was proposed to promote thermal management and lifespan of DUV-LEDs by introducing the ceramic substrate with copper filled thermal hole.
Linlin Xu, Renli Liang, Hanling Long, Jiangnan Dai, Changqing Chen   +4 more
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Increase the IQE by Improving the Crystalline Quality for DUV LEDs

2019
The roadmap for AlGaN based DUV LEDs is similar to that for InGaN based visible LEDs, such that the success of achieving high crystalline-quality epilayers is the precondition for fabricating high-brightness DUV LEDs. This chapter will review the most adopted technologies for growing high-quality Al-rich AlGaN films, which is regarded as the milestone ...
Zi-Hui Zhang, Chunshuang Chu, Kangkai Tian, Yonghui Zhang   +3 more
openaire   +1 more source