Among the printing processes for printed electronic devices, gravure offset and reverse offset method have drawn attention for its fine pattern printing possibility. These printing methods use cliché, which has critical effect on the final product precision and quality. In this research, a novel precise cliché replica method is proposed. It consists of copper sputtering, precise mask pattern printing with 5 um width using reverse offset printing, Ni electroplating, lift-off, etching, and DLC coating. We finally compare the fabricated replica cliché with the original one and print out precise patterns using the replica cliché.
Inkjet printing technology has begun to get into the spotlight in many ways due to the superior price competitiveness to existent semi-conductor process. This paper will introduce a newly devised gap adjustable inkjet printing system for dense and high-temperature-melting materials such as metal paste. The design on the gap adjustable inkjet printing system is discussed in detail for precise control of the size and spacing of the injected metal droplets. Analytic optimization and effects of design parameters are examined and computational work using the axis-symmetric, incompressible, multiphase equations is carried out to predict characteristics of the metal paste jetting and to design optimal micro nozzle prototype. From this analysis, droplet trajectory visualization and velocity vector of ejected droplet have been investigated to characterize the relationship between inlet condition and nozzle profile. Finally, the designed gap adjustable inkjet printing system is fabricated and its peformances are tested according to the change of various gap distances and the droplet characteristics are measured in the view point of precise droplet controllability and productivity.