Cross-scale additive direct-writing fabrication of micro/nano lens arrays by electrohydrodynamic jet printing

Abstract

High-quality micro/nanolens arrays (M/NLAs) are becoming irreplaceable components of various compact and miniaturized optical systems and functional devices. There is urgent requirement for a low-cost, high-efficiency, and high-precision technique to manufacture high-quality M/NLAs to meet their diverse and personalized applications. In this paper, we report the one-step maskless fabrication of M/NLAs via electrohydrodynamic jet (E-jet) printing. In order to get the best morphological parameters of M/NLAs, we adopted the stable cone-jet printing mode with optimized parameters instead of the micro dripping mode. The optical parameters of M/NLAs were analyzed and optimized, and they were influenced by the E-jet printing parameters, the wettability of the substrate, and the viscosity of the UV-curable adhesive. Thus, diverse and customized M/NLAs were obtained. Herein, we realized the fabrication of nanolens with a minimum diameter of 120 nm, and NLAs with different parameters were printed on a silicon substrate, a cantilever of atomic force microscopy probe, and single-layer graphene.

Direct Microtip Focused Electrohydrodynamic Jet Printing of Tailored Microlens Arrays on PDMS Nanofilm‐Modified Substrate

“…The MLAs have excellent uniformity and the deviations of the MLAs diameters are less than 6%, which is comparable to that of previous works using other methods. [ 16,28 ] The arrays of the projected “F” can be clearly observed by the CCD on the false focal plane of the MLAs (Figure 6c). In addition, other letter such as “E” can also be imaged through the MLAs arranged in the letter pattern of “DUT” (Figure 6e).…”

Fabrication of Waterproof Artificial Compound Eyes with Variable Field of View Based on the Bioinspiration from Natural Hierarchical Micro–Nanostructures

“…Even though we have realized the DOD fabrication of NLAs via the stable cone-jet mode in our previous work [ 30 ], the size and position distribution of each nanolens could be controlled precisely using optimized parameters (Fig. S7).…”

“…Due to the flexibility of E-jet printing and its ability to fabricate structures with feature ranging from microscale to nanoscale sizes, its use has been developed for various applications, such as nanomaterials patterning [ 26 ], flexible electronic devices [ 27 ], microfluidic/optical devices [ 28 ], and bio-sensors [ 29 ]. Based on our previous study of the cross-scale fabrication of micro-/nanolens arrays [ 30 ], E-jet printing will provide an effective tool for fabricating desired MLAs and NLAs on a tunable substrate.…”

Microlenses arrays: Fabrication, materials, and applications

“…Electrohydrodynamic jet printing (E‐jet‐printing) is different from inkjet printing in that it uses high‐voltage pulse voltage to induce fluid movement of the polymer (Chen et al, 2006; Huang et al, 2013; Onses et al, 2015) and thereby produce droplets, sprays, or jets. A schematic illustration of how electrohydrodynamic jet printing works in fabricating microlenses is shown in Figure 3 (Zhou et al, 2020). A voltage is applied between the nozzle and the substrate, and the electric field at the tip of nozzle causes the droplets emitted from the nozzle to carry a concentrated charge.…”

“…According to the programmed precise path and the designed digital pattern, the droplets are accurately deposited on the designated position to obtain MLAs. E‐jet‐printing can dynamically adjust the voltage to create droplets with variable sizes (Jin et al, 2014; Lee et al, 2008; Zhou et al, 2020). However, the unstable voltage makes it difficult to print lens arrays with uniform pitch and diameter.…”