Direct Ink Writing of Tungsten Planar Patterns by Extrusion-based Dispensing System

We present an extrusion-based dispensing system designed for the planar patterning of tungsten ink through direct ink writing. This system achieves uniform ink deposition by precisely controlling the dispensing pressure and the motion of the substrate along predefined writing paths. To assess the impact of pressure on pattern geometry, we fabricated line patterns under various pressure conditions and analyzed their widths and thicknesses. To gain further control over pattern width, we employed an adjacent line overlapping strategy, where several lines, each approximately 200 μm wide, were written with partial overlap. We quantitatively verified the relationship between the number of adjacent lines and the resulting pattern width. This method was also adapted to create planar patterns with complex geometries, including variable widths, curved paths, and discontinuous features. The resulting patterns demonstrated uniform quality and precision. These findings confirm that our proposed system provides a versatile solution for fabricating planar conductive patterns with intricate geometries, suitable for applications in printed electronics and interconnects.