Chemical treatment of Ag paste electrodes for surface energy control

Abstract

Though various metal powders are used as the main components of conductive pastes, silver is most widely used owing to its high conductivity and strong corrosion resistance. Hence, silver paste is required for the manufacturing of many items, such as large-area display panels and semiconductor chips. However, electrodes made of silver paste commonly have low surface energy levels, resulting in hydrophobicity. To strengthen the adhesive force between films when silver paste is used as a component in items consisting of many film layers, the silver paste must have high surface energy. In other words, it must show low contact angles in water-drop measurements. Despite the proposal and practicality of the plasma treatment method, this method can cause radical damage, and it is undesirable for batch processes. In this study, the surface energy of a silver paste electrode was changed by dipping it into a sulfuric acid solution. A simple but effective controllable method by which to manage the surface energy is demonstrated, which may be useful for the selective control of specific films on large-area substrates in the future.

Keywords:

• Chemical method
• hydrophilicity
• silver paste
• surface energy

Additional information

Funding

This work was supported by “Human Resources Program in Energy Technology” of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resource from the Ministry of Trade, Industry & Energy (MOTIE) (No. 20184030202200), and by National Research Foundation of Korea (NRF) grant funded by the Korea Government (Ministry of Science and ICT) (NRF-2017R1C1B5017786, NRF-2018R1A4A1025998).