Department of Mechanical Engineering, National University of Singapore , Singapore 117574, Republic of Singapore.
ACS Nano. 2015 Feb 24;9(2):1305-14. doi: 10.1021/nn5051272. Epub 2015 Feb 3.
Moth's eye inspired multiscale ommatidial arrays offer multifunctional properties of great significance in optoelectronic devices. However, a major challenge remains in fabricating these arrays on large-area substrates using a simple and scalable technique. Here we present the fabrication of these multiscale ommatidial arrays over large areas by a distinct approach called sacrificial layer mediated nanoimprinting, which involves nanoimprinting aided by a sacrificial layer. The fabricated arrays exhibited excellent pattern uniformity over the entire patterned area. Optimum dimensions of the multiscale ommatidial arrays determined by the finite-difference time domain simulations served as the design parameters for replicating the arrays on glass. A broadband suppression of reflectance to a minimum of ∼1.4% and omnidirectional antireflection for highly oblique angles of incidence up to 70° were achieved. In addition, superhydrophobicity and superior antifogging characteristics enabled the retention of optical properties even in wet and humid conditions, suggesting reliable optical performance in practical outdoor conditions. We anticipate that these properties could potentially enhance the performance of optoelectronic devices and minimize the influence of in-service conditions. Additionally, as our technique is solely nanoimprinting-based, it may enable scalable and high-throughput fabrication of multiscale ommatidial arrays.
受 moth's eye 启发的多尺度小眼结构阵列在光电设备中具有重要的多功能特性。然而，使用简单且可扩展的技术在大面积衬底上制造这些阵列仍然是一个主要挑战。在这里，我们提出了一种独特的方法，即牺牲层介导的纳米压印来制造大面积的多尺度小眼结构阵列，该方法涉及到牺牲层辅助的纳米压印。所制造的阵列在整个图案化区域表现出出色的图案均匀性。由时域有限差分模拟确定的多尺度小眼结构阵列的最佳尺寸作为在玻璃上复制阵列的设计参数。实现了宽带反射率抑制到最小约 1.4%，并在高达 70°的高倾斜入射角下实现了全向抗反射。此外，超疏水性和优异的防雾特性使得即使在潮湿和潮湿的条件下也能保持光学性能，表明在实际户外条件下具有可靠的光学性能。我们预计这些特性有可能提高光电设备的性能，并最大程度地减少使用条件的影响。此外，由于我们的技术仅基于纳米压印，因此它可能能够实现大规模和高通量的多尺度小眼结构阵列制造。
