KAUST DepartmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Electrical Engineering Program
Online Publication Date2016-11-05
Print Publication Date2017
Permanent link to this recordhttp://hdl.handle.net/10754/622206
MetadataShow full item record
AbstractThe III-N wide-bandgap alloys in the AlInGaN system have many important and unique electrical and optical properties which have been exploited to develop deep-ultraviolet (DUV) optical devices operating at wavelengths < 300 nm, including light-emitting diodes, optically pumped lasers, and photodetectors. In this chapter, we review some aspects of the development and current state of the art of these DUV materials and devices. We describe the growth of III-N materials in the UV region by metalorganic chemical vapor deposition as well as the properties of epitaxial layers and heterostructure devices. In addition, we discuss the simulation and design of DUV laser diodes, the processing of III-N optical devices, and the description of the current state of the art of DUV lasers and photodetectors.
CitationDetchprohm T, Li X, Shen S-C, Yoder PD, Dupuis RD (2016) III-N Wide Bandgap Deep-Ultraviolet Lasers and Photodetectors. Semiconductors and Semimetals. Available: http://dx.doi.org/10.1016/bs.semsem.2016.09.001.
SponsorsThe work at Georgia Institute of Technology was supported over several years in part by DARPA, NSF, and the US Army Research Office. We thank the School of ECE and the College of Engineering at Georgia Institute of Technology for additional support, and RDD acknowledges the continued support of the Steve W. Chaddick Endowed Chair in Electro-Optics and the Georgia Research Alliance.
JournalSemiconductors and Semimetals
Showing items related by title, author, creator and subject.
Deep-Ultraviolet LEDs Incorporated with SiO2-Based Microcavities Toward High-Speed Ultraviolet Light CommunicationYu, Huabin; Memon, Muhammad Hunain; Jia, Hongfeng; Ding, Yifan; Xiao, Shudan; Liu, Xin; Kang, Yang; Wang, Danhao; Zhang, Haochen; Fang, Shi; Gong, Chen; Xu, Zhengyuan; Ooi, Boon S.; Sun, Haiding (Advanced Optical Materials, Wiley, 2022-09-16) [Article]Optical wireless communication (OWC) in the deep-ultraviolet (DUV) band requires an efficient DUV light source with large bandwidth characteristics. In this work, a feasible approach is reported to enlarge the light output power as well as the bandwidth of a DUV light-emitting diode (LED) by embedding a SiO2-based microcavity on which an aluminum (Al) reflector is simultaneously deposited. Consequently, on the one hand, the microcavity with the Al-reflector can facilitate photon escape from the LED to increase the light extraction efficiency, thus enhancing the light output power of the devices. On the other hand, the LED incorporated with a microcavity structure exhibits a reduced resistance–capacitance time constant, leading to an increase in the modulation bandwidth of the LED. Strikingly, the DUV LED incorporated with microcavities represents a significant enhancement of light output power by nearly 30% at 80 mA while exhibiting a higher modulation bandwidth of 12% in comparison to the conventional LED without microcavities. Thus, the implementation of the microcavity and Al reflector on top of a classic LED can enlarge the light output power and modulation bandwidth, eventually facilitating to establish viable high-speed OWC systems.
Lateral-Polarity Structure of AlGaN Quantum Wells: A Promising Approach to Enhancing the Ultraviolet LuminescenceGuo, Wei; Sun, Haiding; Torre, Bruno; Li, Junmei; Sheikhi, Moheb; Jiang, Jiean; Li, Hongwei; Guo, Shiping; Li, Kuang-Hui; Lin, Ronghui; Giugni, Andrea; Di Fabrizio, Enzo M.; Li, Xiaohang; Ye, Jichun (Advanced Functional Materials, Wiley, 2018-06-08) [Article]Aluminum-gallium-nitride alloys (Al x Ga1– x N, 0 ≤ x ≤ 1) can emit light covering the ultraviolet spectrum from 210 to 360 nm. However, these emitters have not fulfilled their full promise to replace the toxic and fragile mercury UV lamps due to their low efficiencies. This study demonstrates a promising approach to enhancing the luminescence efficiency of AlGaN multiple quantum wells (MQWs) via the introduction of a lateral-polarity structure (LPS) comprising both III and N-polar domains. The enhanced luminescence in LPS is attributed to the surface roughening, and compositional inhomogeneities in the N-polar domain. The space-resolved internal quantum efficiency (IQE) mapping shows a higher relative IQE in N-polar domains and near inversion domain boundaries, providing strong evidence of enhanced radiative recombination efficiency in the LPS. These experimental observations are in good agreement with the theoretical calculations, where both lateral and vertical band diagrams are investigated. This work suggests that the introduction of the LPS in AlGaN-based MQWs can provide unprecedented tunability in achieving higher luminescence performance in the development of solid state light sources.
Diode junction temperature in ultraviolet AlGaN quantum-disks-in-nanowiresPriante, Davide; Elafandy, Rami T.; Prabaswara, Aditya; Janjua, Bilal; Zhao, Chao; Alias, Mohd Sharizal; Tangi, Malleswararao; Alaskar, Yazeed; Albadri, Abdulrahman M.; Alyamani, Ahmed Y.; Ng, Tien Khee; Ooi, Boon S. (Journal of Applied Physics, AIP Publishing, 2018-07-05) [Article]The diode junction temperature (Tj) of light emitting devices is a key parameter affecting the efficiency, output power, and reliability. Herein, we present experimental measurements of the Tj on ultraviolet (UV) AlGaN nanowire (NW) light emitting diodes (LEDs), grown on a thin metal-film and silicon substrate using the diode forward voltage and electroluminescence peak-shift methods. The forward-voltage vs temperature curves show temperature coefficient dVF/dT values of −6.3 mV/°C and −5.2 mV/°C, respectively. The significantly smaller Tj of ∼61 °C is measured for the sample on the metal substrate, as compared to that of the sample on silicon (∼105 °C), at 50 mA, which results from the better electrical-to-optical energy conversion and the absence of the thermally insulating SiNx at the NWs/silicon interface. In contrast to the reported higher Tj values for AlGaN planar LEDs exhibiting low lateral and vertical heat dissipation, we obtained a relatively lower Tj at similar values of injection current. Lower temperatures are also achieved using an Infrared camera, confirming that the Tj reaches higher values than the overall device temperature. Furthermore, the heat source density is simulated and compared to experimental data. This work provides insight into addressing the high junction temperature limitations in light-emitters, by using a highly conductive thin metal substrate, and it aims to realize UV AlGaN NWs for high power and reliable emitting devices.