Novel Image Trimming Algorithm for Use with Ink Jet Printing Fabrication

For the development of new inkjet printing (IJP) technology, instead of traditional processes, such as spinning, screen printing, photolithography, and laser printing, used for semiconductor and display fields, what are the obstacles to mass production? IJP is an ideal technology for fabricating material layering on a specific substrate that needs to be patterned. However, the line width presence often conflicts with the thin film requirement, i.e., to obtain a better line edge quality, the overlap distance of drops needs to be tuned closer and this results in greater thickness, which deteriorates the electronic performance. Besides, sometimes the image resolution for a metal circuit will be expected to fall within a tunable region, up to ±3 μm for a high level IC carrier board, in order to correct the image deterioration caused during the prior layering process. Those process needs are hard to achieve because of the innate characteristics of IJP transfer into the raster image data format. This paper proposes a novel image trimming method to transfer an original image to a trimmed image, based on the spreading factor between the liquid-solid interface and the assumption of linear superposition for drop-to-drop overlapping, as well as a versatile filtering function built-in as an auxiliary look-up table to modulate layer thickness. In detail, the trimming method included the procedure of pattern identification and location, image separation, seamless image merging, image boundary compensation, image trimming on spreading factor, and image reconstruction. The filtering method included the local characteristic of boundary inspection with a defined correcting function and varied filtering pattern applied to the inner field of boundary. The test pattern found that the circuit was satisfactory in terms of thickness and line width, according to expectation.