Gibasiewicz Krzysztof, Bojarska-Cieślińska Agata, Muzioł Grzegorz, Skierbiszewski Czesław, Grzanka Szymon, Kafar Anna, Perlin Piotr, Najda Stephen, Suski Tadeusz
Opt Lett. 2020 Aug 1;45(15):4332-4335. doi: 10.1364/OL.394629.
We have fabricated tunnel-junction InGaN micro-LEDs using plasma-assisted molecular beam epitaxy technology, with top-down processing on GaN substrates. Devices have diameters between 5 µm and 100 µm. All of the devices emit light at 450 nm at a driving current density of about 10. We demonstrate that within micro-LEDs ranging in size from 100 µm down to 5 µm, the properties of these devices, both electrical and optical, are fully scalable. That means we can reproduce all electro-optical characteristics using a single set of parameters. Most notably, we do not observe any enhancement of non-radiative recombination for the smallest devices. We assign this result to a modification of the fabrication process, i.e., replacement of deep dry etching by a tunnel junction for the current confinement. These devices show excellent thermal stability of their light emission characteristics, enabling operation at current densities up to 1.
我们使用等离子体辅助分子束外延技术，在氮化镓衬底上进行自上而下的加工，制造出了隧道结氮化铟镓微型发光二极管。器件直径在5微米至100微米之间。所有器件在驱动电流密度约为10时，均在450纳米处发光。我们证明，在尺寸从100微米到5微米的微型发光二极管中，这些器件的电学和光学特性均可完全扩展。这意味着我们可以使用一组参数重现所有电光特性。最值得注意的是，对于最小的器件，我们没有观察到非辐射复合的任何增强。我们将这一结果归因于制造工艺的改进，即用隧道结替代深干法刻蚀来实现电流限制。这些器件的发光特性表现出优异的热稳定性，能够在高达1的电流密度下工作。
