Nanomaterial disordering in AlGaN/GaN UV LED structures

2nd International School and Conference Saint-Petersburg OPEN on Optoelectronics, Photonics, Engineering and Nanostructures

Shabunina, E.I.^1 ; Levinshtein, M.E.^1 ; Kulagina, M.M.^1 ; Kurin, S.Yu.^2 ; Chernyakov, A.E.^3 ; Petrov, V.N.^1 ; Ratnikov, V.V.^1 ; Smirnova, I.N.^1 ; Troshkov, S.I.^1 ; Shmidt, N.M.^1 ; Usikov, A.S.^4,5 ; Helava, H.^5 ; Makarov, Yu.N.^2,5

Ioffe Physical Technical Institute, Polytekhnicheskaya 26, St. Petersburg

194021, Russia^1

Nitride Crystals Group Ltd., 27 Engels av., St Petersburg

194156, Russia^2

Submicron Heterostructures for Microelectronics Research and Engineering Center RAS, Polytekhnicheskaya 26, St. Petersburg

194021, Russia^3

University ITMO, Kronverkskiy pr. 49, St. Petersburg

197101, Russia^4

Nitride Crystals Inc., 181E Industry Ct., Deer Park

NY

11729, United States^5

关键词: Active regions;    Extended defect systems;    External quantum efficiency;    Injected carriers;    Multifractal analysis;    Multifractal parameters;    Nanostructural;    Radiative recombination;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/643/1/012128/pdf
DOI  :  10.1088/1742-6596/643/1/012128

来源: IOP

【 摘 要 】

Multifractal analysis was applied to characterize quantitatively nanostructural disordering in HVPE-grown AlGaN/GaN UV LED structures. A higher level of leakage currents shunting the active region of LEDs by an extended defect system is correlated with higher values of multifractal parameters (MFs). As a result, the concentration of injected carriers participating in radiative recombination in the active region is reduced. MFs and the conductivity of quasi-ohmic shunts localized in an extended defect system are higher in AlGaN/GaN structures than in InGaN/GaN structures. It is one of the reasons behind the low external quantum efficiency of AlGaN/GaN UV LEDs.