LAUSR

Abstract Micro/nano fiber structures can be printed on a non-conducting substrate by applying an electrohydrodynamic (EHD) direct-writing technique. The combination of Wet Etching and Deep Reactive Ion Etching is used to fabricate a hollow micro-needles array as spinneret (microneedle with the 40 μm hole diameter, 80 μm outer diameter, and 100 μm height). An experimental mechano-electrospinning setup was designed and implemented to deposit single micro-nano fiber patterns. Microneedle and plastic syringe are mounted as two different spinnerets in this setup. Different shapes and sizes fibers are created by two mentioned spinnerets. This setup can control the distance and the voltage between spinneret and collector, collector speed, and fluid flow rate. The mean width of the electro-spun straight-line single fiber decreases from 1.4 to 0.5 μm by the microneedle and from 3.5 to 0.85 μm by plastic syringe when the velocity of the substrate increased from 50 to 200 mm/s. By changing the collector speed from 20 to 60 mm/s, various single micro/nanofiber patterns electrospun by microneedle such as sinusoidal, helical, hat-shaped, and straight-line are achieved at 1–2.5 kV voltage, 1 mm collector to microneedle distance, 0.1 mL/h flow rate, and 23 Wt% polymer solution concentration. Because of electrical repulsive force, the single charged fiber is developed in a path parallel to the margin of the previously developed charged pattern on the substrate. Single fiber with sinusoidal, hat-shaped, and helical patterns can be used in special applications such as flexible and printed electronics.