This research studies the performance of n-side up thin-film AlGaInP-based vertical micro-light-emitting diodes (V- $\mu $ LEDs) with four different chip sizes, $100\times100$ , $70\times70$ , $50\times50$ , and $25\times 25\,\,\mu \text{m}^{2}$ , on a $50~\mu \text{m}$ thick composite metal (copper/Invar/copper; CIC) substrate. The LEDs were fabricated to understand the electrical and optical properties of AlGaInP V- $\mu $ LEDs as functions of chip sizes. For device performance, the small LEDs provide a larger current density under the same voltage and present smaller forward voltage, a low red-shift phenomenon, and low output power density. For the external quantum efficiency (EQE) of device, larger LEDs exhibit maximum EQE at lower current density as compared to smaller LEDs. The injection of a small current at the same current density obtains the emission image. The obtained data suggest that the smallest V- $\mu $ LEDs exude a sidewall effect that could impact the device performance.

中文翻译：

---

Cu / Invar / Cu金属衬底的AlGaInP红色垂直微发光二极管的电学和光学性能研究

这项研究研究了基于n面朝上的AlGaInP薄膜垂直微发光二极管（V- $ \亩$ LED）具有四种不同的芯片尺寸， $ 100 \次100 $ ， 70美元/次70美元 ， $ 50 /次50 $ ， 和 $ 25 \ times 25 \，\，\ mu \ text {m} ^ {2} $ ，在 $ 50〜\ mu \ text {m} $ 厚的复合金属（铜/因瓦合金/铜； CIC）基板。制作LED是为了了解AlGaInP V-的电学和光学特性。 $ \亩$ LED作为芯片尺寸的函数。为了提高设备性能，小型LED在相同电压下可提供更大的电流密度，并具有更小的正向电压，低红移现象和低输出功率密度。对于设备的外部量子效率（EQE），与较小的LED相比，较大的LED在较低的电流密度下表现出最大的EQE。以相同的电流密度注入小电流可获得发射图像。获得的数据表明，最小的V- $ \亩$ LED散发出可能影响器件性能的侧壁效应。