Ra Yong-Ho, Lee Cheul-Ro
Optic & Electronic Component Material Center, Korea Institute of Ceramic Engineering & Technology, Jinju 52851, Republic of Korea.
School of Advanced Materials Engineering, Engineering College, Chonbuk National University, Deokjin-dong 664-14, Jeonju 54896, Republic of Korea.
Nano Lett. 2020 Jun 10;20(6):4162-4168. doi: 10.1021/acs.nanolett.0c00420. Epub 2020 May 6.
We have demonstrated a new class of phosphor-free white LEDs with the use of tunnel junction structure in nonpolar core-shell InGaN nanowires. It is confirmed that the tunnel junction based nanowire LEDs can eliminate the use of the resistive p-GaN:Mg contact layer, leading to significantly enhanced hole injection and dramatically reduced voltage loss. The nonpolar core-shell nanowire heterostructure showed the enhanced carrier injection efficiency through the widened shell n-GaN contact area. The TEM analysis verified that the core-shell Al tunnel junction layers were uniformly grown on nonpolar surfaces of the GaN wurtzite crystal nanowire structure. We have also showed the monolithic integration of multiple-color emission on a single chip by using the multiple-stacked tunnel junction core-shell nanowire heterostructure. Compared to the conventional film based quantum well LEDs, the demonstrated nonpolar core-shell tunnel junction nanowire LEDs will be a very promising candidate for future solid-state lighting applications as well as phosphor-free white LEDs.
我们展示了一类新型的无磷白光发光二极管，其利用了非极性核壳结构氮化铟镓纳米线中的隧道结结构。证实基于隧道结的纳米线发光二极管能够消除电阻性p型氮化镓：镁接触层的使用，从而显著增强空穴注入并大幅降低电压损耗。非极性核壳纳米线异质结构通过拓宽的壳层n型氮化镓接触面积展现出增强的载流子注入效率。透射电子显微镜分析证实核壳铝隧道结层在纤锌矿晶体结构的氮化镓纳米线的非极性表面上均匀生长而成。我们还展示了通过使用多层堆叠的隧道结核壳纳米线异质结构在单个芯片上实现多色发射的单片集成。与传统的基于薄膜的量子阱发光二极管相比而言,所展示的非极性核壳隧道结纳米线发光二极管对于未来固态照明应用以及无磷白光发光二极管而言将是非常有前景的候选者。
