Investigation to improve the printing accuracy of low-temperature paste based on rheological and optical measurement

The low-temperature thick film paste serves as the fundamental material in the electronic printing industry. Currently there is a growing trend towards integration and miniaturization in electronic printing, making high-precision printing increasingly demanded. However, due to the process limitations of screen printing, how to further improve the printing accuracy at a low cost is still a problem to be solved. In this paper, a selection method of low-temperature paste additives was proposed, enabling self-shrinking during the drying process post-printing, thereby achieving enhanced printing accuracy without necessitating equipment modifications. The organic medium with good dispersibility and stable performance was obtained by mixing resin binder, solvent and additive. The constitutive fitting was used to understand its characteristics. The rheological properties of the low-temperature paste were analyzed to comprehend their behavior and structural characteristics under varying conditions, as well as validate their printing performance. Through the screen printing process, it was found that the width of the printed line after sintering decreased to only 80.8% of its original size after sintering. This study provides theoretical guidance for low-temperature electronic paste research.