硅基板激光微熔覆电子浆料制备导体的研究

激光微细熔覆电子浆料技术是一种新型的柔性布线技术，采用激光精密加工系统对电子浆料进行处理以制备导线，具有柔性化程度高、电路图形设计、修改简捷、适合小批量生产等优点。特别是可以制备最小线宽为20 μm左右的导体，突破了传统丝网印刷工艺制备导线宽度的极限。利用激光微细熔覆工艺在单晶硅基板上制备出了银导线。所制备导线的最小宽度在30 μm左右，其电阻率和块状银在同一个数量级，能够满足应用要求。利用悬挂法测定其与硅基板的结合强度在兆帕数量级，与传统丝网印刷工艺相当。相关的工艺实验还表明，导体线宽随激光功率密度的增加而增加，随激光扫描速度的增加而减小;对于特定厚度的浆料预置层，激光扫描参数存在一个最佳的范围。激光扫描之后的高温热处理工艺有利于导线导电性能及其与硅基板的结合强度的进一步提高。

Conductor Fabrication with Laser Micro-Cladding Electronic Pastes on Si Substrate

Laser micro-cladding technology is a novel method for circuit fabrication. With this method, electronic paste was disposed and sintered by laser process system to fabricate conductor. With the advantages of highly flexibility, easy design and modification, high efficiency and short cycle time, It can fabricate the conductor with minimum line width of 20 μm, which exceeds the limitation of traditional method. In previous work, the circuit fabrication on ceramic, glass and epoxy resin substrates by laser micro-cladding technology was researched. In this article, the conductor was fabricated on semiconductor (Si) substrate. Its minimum line width was about 30 μm and resistivity was at the same level with block Ag,which can satisfy the industrial requirements. The adhesion between conductor and Si substrate was at the order of MPa, which was equivalent with the traditional printing process. The experimental results also demonstrated that the conductor width increases with laser power density increasing, but decreases with the laser scanning speed. There is an optimal parameter range in laser processing. The heat treatment after laser scanning is benefit for conductor's electric performance and adhesion between conductor and Si substrate.