State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.
Flexible Electronics Research Center, Huazhong University of Science and Technology, Wuhan 430074, China.
Lab Chip. 2022 Oct 11;22(20):3877-3884. doi: 10.1039/d2lc00624c.
Electrohydrodynamic (EHD) printing is a promising micro/nanofabrication technique, due to its ultra-high resolution and wide material applicability. However, it suffers from low printing efficiency which urgently calls for a high density and addressable nozzle array. This paper presents a nozzle array chip made of a silicon plate and polymer nozzle structure, where the large silicon plate is conducive to a uniform spatial electric field distribution, and the polymer SU8 nozzle can inhibit tip discharge due to its insulating character and liquid flooding as SU8 is hydrophobic. By carefully designing the nozzle array structure simulation, and fabricating it through MEMS technology, a high-density nozzle array chip has been achieved which can generate very uniform dots without crosstalk. Meanwhile, by adding extractors underneath the nozzle array, and utilizing a digital switch array to tune their on/off state, addressable printing has been realized. This novel printhead design has solved the discharge, liquid flooding, and crosstalk behavior in EHD nozzle arrays, and is compatible with traditional silicon-based MEMS technology, which will promote the practical applications of EHD printing in micro/nanoelectronics, biomedical/energy devices,
静电喷射（EHD）打印是一种很有前途的微纳制造技术，因为它具有超高的分辨率和广泛的材料适用性。然而，它的打印效率很低，这就迫切需要高密度和可寻址的喷嘴阵列。本文提出了一种由硅片和聚合物喷嘴结构组成的喷嘴阵列芯片，其中大硅片有利于均匀的空间电场分布，而聚合物 SU8 喷嘴由于其绝缘特性和液体浸润性（因为 SU8 是疏水性的）可以抑制尖端放电。通过仔细设计喷嘴阵列结构、进行模拟，并通过微机电系统（MEMS）技术进行制造，已经实现了高密度喷嘴阵列芯片，可以产生非常均匀的点，而不会发生串扰。同时，通过在喷嘴阵列下方添加提取器，并利用数字开关阵列来调节它们的开/关状态，实现了可寻址打印。这种新颖的打印头设计解决了 EHD 喷嘴阵列中的放电、液体浸润和串扰行为问题，并且与传统的硅基 MEMS 技术兼容，这将促进 EHD 打印在微纳电子、生物医学/能源设备等领域的实际应用。
