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Thin transparent oxide layers are typically patterned for use in electronic products including semiconductors, displays, and solar cells for applications such as transparent electrodes, insulating films, and encapsulation films. Conventional patterning methods have traditionally been used in photolithography and lift-off processes. Photolithography employs the wet development process, which has disadvantages such as potential undercut effects, swelling, chemical contamination, and high process costs. On the other hand, laser ablation, which has the advantages of high accuracy, high speed, a noncontact nature, and selective processing, can be used to pattern thin films. However, absorption in transparent oxide films is usually low. In this study, experiments were conducted to determine the ablation characteristics of mask layers. The factors affecting ablation, including beam radii, fluences, overlap ratios, and coating thicknesses, were examined; and the parameters characteristic of residue-free ablation, namely the ablation threshold, minimum fluence, and minimum ablation linewidth, were also examined. The experimental results revealed that the beam radius was an important parameter in determining the resolutions of transparent films and substrates. [ABSTRACT FROM AUTHOR]

This paper presents the feasibility of Fraunhofer diffraction analysis as a measure of the size of fast‐moving inkjet droplets. This measurement method showed that an inkjet droplet measurement tool was possible with a good balance of real‐time measurement and accuracy. [ABSTRACT FROM AUTHOR]

Inkjet printers have started to manufacture OLED/QLED pixel arrays for the display industry, and the precise measurement and control of ink droplet volume during the printing process has become important. We investigated the feasibility of Fraunhofer diffraction analysis as a volume measurement tool for fast-moving inkjet droplets. To confirm the basic idea, two Fraunhofer diffraction-based methods were used to calculate the wire diameters of well-known sized and steady-positioned metal wires. The first method was to curve-fit the whole measured diffraction intensity curve with the extensive Fraunhofer diffraction equation. The second one was to use the simple approximate diameter calculation equation with the measured position data of minimum diffraction intensity. The metal wire diameters calculated by the two methods showed less than 1.17% error. For the size measurement of fast-moving inkjet droplets, the first method showed 24.5 µm diameter and 7.7 pL volume, while the second method showed 25.4 µm diameter and 8.58 pL volume. We found that the second method was more suitable for real-time inkjet monitoring because its average computer calculation time was 33 ms, and the first method took an average of 34 ms, about 1000 times more CPU time. Hence, Fraunhofer diffraction analysis as an inkjet droplet volume measurement tool was feasible with a good balance of measurement time and measurement accuracy. [ABSTRACT FROM AUTHOR]