Lin, C.-H.C.-H.LinSu, C.-Y.C.-Y.SuYao, Y.-F.Y.-F.YaoSu, M.-Y.M.-Y.SuChiang, H.-C.H.-C.ChiangTsai, M.-C.M.-C.TsaiLiu, W.-H.W.-H.LiuTu, C.-G.C.-G.TuYang, C.C.C.C.YangHuang, F.-W.F.-W.HuangLee, C.-L.C.-L.LeeHsu, T.-C.T.-C.HsuYEAN-WOEI KIANG2020-06-112020-06-11201801469592https://scholars.lib.ntu.edu.tw/handle/123456789/497807https://www.scopus.com/inward/record.uri?eid=2-s2.0-85056470091&doi=10.1364%2fOL.43.005631&partnerID=40&md5=e2bbf86cab1e4ce8f73116b5deb98410It is usually believed that surface plasmon (SP) coupling is practically useful only for improving the performance of a light-emitting diode (LED) with a low intrinsic internal quantum efficiency (IQE). In this Letter, we demonstrate that the performance of a commercial-quality blue LED with a high IQE (>80%) can still be significantly improved through SP coupling based on a surface Ag nanoparticle (NP) structure. The performance improvement of such an LED is achieved by increasing the Mg doping concentration in its p-AlGaN electron blocking layer to enhance the hole injection efficiency such that the p-GaN layer thickness can be significantly reduced without sacrificing its electrical property. In this situation, the distance between surface Ag NPs and quantum wells is decreased and hence SP coupling strength is increased. By reducing the distance between the surface Ag NPs and the top quantum well to 66 nm, the IQE can be increased to almost 90% (an ∼11% enhancement) and the electroluminescence intensity can be enhanced by ∼24%. © 2018 Optical Society of America.Aluminum gallium nitride; Charge injection; Efficiency; Hole concentration; III-V semiconductors; Light; Light emitting diodes; Semiconductor quantum wells; Silver nanoparticles; Surface plasmons; Commercial qualities; Electroluminescence intensity; Electron blocking layer; Emission efficiencies; Internal quantum efficiency; Light emitting diode (LED); Performance improvements; Surface plasmon coupling; Quantum efficiencyjournal article10.1364/OL.43.005631304399122-s2.0-85056470091