Fine pattern formation with solder paste using screen printing with stainless steel mesh-cut screen mask

Abstract

Stencil contact printing is widely used to fabricate conductive patterns, and it is particularly used with solder paste to create interconnections. However, stencil contact printing is becoming inefficient for electronic components owing to the ever decreasing size of the components. An alternative method for fine pattern formation is screen printing, i.e. gap printing with a screen mask, which exploits the thixotropic characteristics of solder paste. Nevertheless, the mesh of the screen mask prevents the paste from permeating, resulting in irregular patterns. To address this issue, we propose gap printing with a mesh-cut screen mask. In this paper, we describe the fabrication procedure of the mask, and demonstrate the effectiveness of the proposed printing in the formation of fine and thick circular patterns; the patterns are shown to have low variations in size compared with conventional printing methods. The proposed method is expected to contribute to the further miniaturisation of electronic devices.