氧等离子体处理对GaAs表面单层自组装SiO2纳米球薄膜的影响

二维纳米阵列结构因其重要的光学性能被广泛应用于各类光电子器件。本文对自组装单层SiO2纳米球掩模刻蚀法制备GaAs纳米柱二维阵列结构的关键工艺技术进行了研究。采用旋涂法在GaAs表面制备自组装单层SiO2纳米球,重点研究了GaAs表面氧等离子体亲水处理工艺对纳米球排列特性的影响,获得最佳工艺条件为功率配比100 W+80 W、腔室压力4 Pa、氧气流量20 mL/min、处理时间1200 s,并最终得到排列紧密的大面积单层纳米球薄膜。以单层纳米球为掩模,采用感应耦合等离子体刻蚀技术在GaAs表面制备了纳米柱阵列并测试了其表面光反射谱。测试结果表明,GaAs纳米柱阵列在特定波段的反射率降低至5%,远低于表面无纳米结构的薄膜材料表面高达40%的光反射。分析表明纳米柱可以激发米氏散射共振效应,从而有效降低反射率并提升光吸收。

Effect of Oxygen Plasma Treatment on Monolayer Self-assembled SiO2 Nanosphere Thin Films on GaAs Surface

Two-dimensional nano-array structures have been widely used in many optoelectronic devices due to their excellent optical performances.In this work,nano-pillar arrays were fabricated on GaAs substrate by self-assembled monolayer SiO2 nanospheres etching.Monolayer SiO2 nanospheres were self-assembled on GaAs substrate by rotary coating.The order of the nanosphere distribution was improved by improving the oxygen plasma hydrophilic treatment process of GaAs surface,and a large area of tightly arranged monolayer nanosphere was obtained under the power ratio of 100 W+80 W,the chamber pressure of 4 Pa,the oxygen flow rate of 20 mL/min and the etching time of 1200 s.Taken this monolayer nanosphere as the etching mask,highly ordered GaAs nano-pillar array was then fabricated by inductively coupled plasma etching.The reflectivity of the GaAs nano-pillar array structure was found to be about 5%in a specific band by spectral analysis,which shows that light absorption can be enhanced effectively and can further match the requirements of actual optoelectronic devices.