This paper outlines the fabrication process of the partition component, a crucial element in digital PCR. The partition component consists of thousands of micro-wells capable of holding small volumes of reagents. In this study, the partition component was created in a honeycomb structure, with hexagonally shaped micro-wells measuring 100 μm in size and spaced 20 μm apart. The fabrication process involved using photolithography, lift-off, and electroplating techniques. Photolithography and lift-off processes were employed to create a pattern of Cu metal layers in a hexagonal honeycomb arrangement on a glass substrate. Subsequently, the Cu metal-patterned substrate was used to produce pillar patterns of SU-8 with a high aspect ratio using photolithography. Finally, the gaps between the SU-8 pillar patterns were filled with nickel through electroplating, completing the partition component. The micro-wells in the partition component were designed to have an aspect ratio of 4-5; however, in this study, micro-wells with an aspect ratio of 2 and a depth of 200 μm were fabricated.
With the progress of flexible devices, numerous researchers aim to manufacture the flexible battery with freefrom at various scales. Laser cutting is considered as one of the essential processes to achieve on-demand manufacturing but continuous wave or long-pulse laser beam may cause large heat affect zone (HAZ) in cutting edge and may even result in failure of battery function. Herein, it was demonstrated that the sophisticated cutting process using ultra-short pulse laser is applicable for tailoring of flexible battery with multilayered structure. Based on the comparison of cutting results using nanosecond laser and femtosecond laser, we confirmed that laser cutting by femtosecond laser induces much less thermal damage on thin foil electrodes, separator, and electrolyte. Furthermore, we investigated the interaction of femtosecond laser with the materials composed of a flexible battery and implemented a process for cutting each material without causing any critical damage. To prevent a short circuit between the anode and cathode, which usually occurs during laser cutting of the actual battery, the double-side cutting process was done by adjusting the focal points of the laser beam. We assume that the proposed approach can be applied in a roll-to-roll based cutting process for the mass-production of flexible devices.
We propose a dual grating alignment technique for roll-to-roll positioning which allows achieving nanometer scale alignment by using micro-size marks. The high precision alignment system were designed and manufactured. It was confirmed that the optical system was properly adjusted and fully aligned with the dual gratings. The experiment and computer simulation results were presented. Alignment accuracy below 50 ㎚ was achieved.