Li Yikang, Wang Dazhi, Feng Yiwen, Chen Xiangji, Chen Xu, Liu Chang, Li Yanteng, Suo Liujia, Zhang Ran, Zhang Xiaopeng, Liu Ben, Wang Fengshu, Liang Shiwen, Kong Lingjie, Fu Qiang, Ren Tongqun, Wang Tiesheng
Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, 116024, Dalian, China.
State Key Laboratory of High-performance Precision Manufacturing, Dalian University of Technology, 116024, Dalian, China.
Microsyst Nanoeng. 2025 May 12;11(1):81. doi: 10.1038/s41378-025-00936-0.
Three-dimensional (3D) conductive structures significantly reduce flexible circuit complexity and enhance circuit integration. Direct extrusion printing technology offers the advantages of various material applicability and high flexibility for fabricating filamentary interconnects. The printing resolution is, however, highly dependent on the needle size. A micro-printing method was proposed based on fluid drawing to fabricate freestanding 3D conductive structures. The delicate structure is drawn out under the tension when printing. The printing material is a high-viscosity ink composed of silver nanoparticles (AgNPs) and polyvinylpyrrolidone (PVP). The viscosity is controlled by evaporating the ink's solvent for drawing prints. This unique printing method utilizes a single needle, controlled by precise air pressure and speed, to construct 3D filamentary structures with varied wire widths. The 3D conductive structures exhibit superior structural retention and enhanced conductivity by thermal treatment. The drawing printing method has been successfully implemented on flexible circuits, including light-emitting diode (LED) arrays, thermal imaging displays, and multivibrator circuits. This work establishes a novel paradigm for flexible electronics manufacturing through fluid-drawing printing, achieving unprecedented customization and compatibility in fabricating 3D interconnects.
三维（3D）导电结构显著降低了柔性电路的复杂性并增强了电路集成度。直接挤压印刷技术在制造丝状互连方面具有多种材料适用性和高灵活性的优点。然而，印刷分辨率高度依赖于针头尺寸。基于流体拉伸提出了一种微印刷方法来制造独立的3D导电结构。在印刷时，精细的结构在张力作用下被拉伸出来。印刷材料是一种由银纳米颗粒（AgNP）和聚乙烯吡咯烷酮（PVP）组成的高粘度墨水。通过蒸发墨水溶剂来控制粘度以进行印刷。这种独特的印刷方法利用一根由精确气压和速度控制的针头来构建具有不同线宽的3D丝状结构。通过热处理，3D导电结构表现出优异的结构稳定性和增强的导电性。拉伸印刷方法已成功应用于柔性电路，包括发光二极管（LED）阵列、热成像显示器和多谐振荡器电路。这项工作通过流体拉伸印刷为柔性电子制造建立了一种新的范例，在制造3D互连方面实现了前所未有的定制性和兼容性。
