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Abstract：
In this study, arrays of μLEDs in four different sizes (5 × 5 μm2, 10 × 10 μm2, 25 × 25 μm2, 50 × 50 μm2) were fabricated using a flip-chip bonding process. Two passivation processes were investigated with one involving a single layer of SiO2 deposited using plasma-enhanced chemical vapor deposition (PECVD) and the other incorporating Al2O3 deposited by atomic layer deposition (ALD) beneath the SiO2 layer. Owing to superior coverage and protection, the double-layers passivation process resulted in a three-order lower leakage current of μLEDs in the 5 μm chip-sized μLED arrays. Furthermore, higher light output power of μLEDs was observed in each chip-sized μLED array with double layers passivation. Particularly, the highest EQE value 21.9% of μLEDs array with 5 μm × 5 μm chip size was achieved with the double-layers passivation. The EQE value of μLEDs array was improved by 4.4 times by introducing the double-layers passivation as compared with that of μLEDs array with single layer passivation. Finally, more uniform light emission patterns were observed in the μLEDs with 5 μm × 5 μm chip size fabricated by double-layer passivation process using ImageJ software.
摘要：
在这项研究中,使用倒装芯片键合工艺制造了四种不同尺寸（5×5μm2，10×10μm2，25×25μm2，50×50μm2）的μLED阵列。研究了两种钝化工艺，一种是使用等离子体增强化学气相沉积（PECVD）沉积的单层SiO2，另一种是在SiO2层下方通过原子层沉积（ALD）沉积的Al2O3。由于优越的覆盖和保护，双层钝化工艺导致5μm芯片尺寸的μLED阵列中μLED的漏电流降低了三阶。此外，在具有双层钝化的每个芯片尺寸的μLED阵列中观察到更高的μLED光输出功率。特别是,通过双层钝化，具有5μm×5μm芯片尺寸的μLED阵列的EQE值最高为21.9％。与单层钝化的μLED阵列相比，通过引入双层钝化，μLED阵列的EQE值提高了4.4倍。最后,使用ImageJ软件通过双层钝化工艺在5μm×5μm芯片尺寸的μLED中观察到更均匀的发光模式。
