Surface Acoustic Wave (SAW) RF-filters are essential components for wireless communication. Miniaturization and cost reduction are the main driving forces for the development of these components. Up to now the dominant technology to connect the miniaturized filters are solder bumps. For further miniaturization a technology to fabricate copper pillar bumps (CPB) on SAW RF-filters was developed and the second level reliability of the components was tested. In this paper the physical analysis of CPB interconnects with a high resolution FIB SEM and EDX will be explained in detail. We will also show results of this analysis including the formation of the intermetallic phases and the structure and the degradation of the Ni barrier layers.

表面声波 (SAW) 射频滤波器是无线通信的重要组件。小型化和降低成本是这些组件发展的主要动力。到目前为止，连接微型滤波器的主要技术是焊料凸点。为了进一步小型化，开发了一种在 SAW 射频滤波器上制造铜柱凸块 (CPB) 的技术，并测试了组件的二级可靠性。在本文中，将详细解释具有高分辨率 FIB SEM 和 EDX 的 CPB 互连的物理分析。我们还将展示该分析的结果，包括金属间相的形成以及 Ni 势垒层的结构和退化。