耐折高导电性银浆的制备

Preparation of Silver Pastes with High Electrical Conductivity After Folding

摘要:

研究了银片粒径对折叠前后银浆电导率的影响。采用不同粒径的片状银制备了具有良好导电性能的低温固化耐折导电银浆料，将银浆网印在聚酰亚胺基板上，在140 ℃下烧结形成网印电路。用微欧姆计检测了印刷电路的电阻率，对印刷银电路折叠前后的电阻变化进行了检测，并用扫描电镜对其表面形貌进行了研究，分析了导电机理。结果表明，小片Ag作为未连接薄片之间的桥梁，在折叠后填补了空白，形成导电网络，提高了折叠后的银浆导电性能。

Abstract:

The influence of Ag flake size on the electrical conductivity of silver pastes before and after folding was investigated. The low-temperature curing conductive silver pastes with good electrical conductivity after folding were fabricated using Ag flake with different flake sizes. Then the silver pastes were screen-printed on the polyimide substrate and sintered at 140 °C to form the circuits. The electrical resistivity of the printed circuits was detected by micro-ohmmeter. In order to measure the flexibility of Ag circuits, the variance of electrical resistivity of Ag circuits was detected after they were folded. The surface morphology of the folded Ag circuits was observed by the scanning electron microscopy. The conductive mechanism was analyzed. The results show that the small Ag flakes can act as the bridge between the unconnected flakes and fill the gaps after the circuits are folded, which forms the conductive networks, thereby improving the electrical conductivity after folding.