SOLDERON™ BP IN 1000 indium plating chemistry is designed for solder plating processes used in advanced wafer-level packaging for emerging applications that are sensitive to temperature. Its use minimizes substrate warpage and stress, and reduces the possibility of damaging materials in delicate devices due to significantly reduced reflow temperature. SOLDERON BP IN 1000 indium strikes a balance to achieve optimized performance, versatility and cost of ownership requirements. It extends the SOLDERON family into applications where SnAg can’t be used.
Table 1: Target applications
|Optoelectronics bonding/assembly (multi-sensing CMOS image sensor, display)|
|3D Si die/wafer stacking|
|Flexible and/or coreless substrate assembly|
|Compound semiconductors (III-V materials)|
SOLDERON BP IN 1000 Indium serves a wide set of applications, from C4 bumps for conventional flip chip processes, to capping for Cu pillars, and µbumps in 3D stacking using TSV processes (Figures 1 and 2). It is also compatible with mainstream bumping photoresist materials, and can be integrated directly into existing process flows. It has demonstrated good within-die co-planarity in test vehicles during bumping and capping applications. Additionally, its low melting temperature also makes it a good option for bonding multiple thin layers.
SOLDERON BP IN 1000 Indium achieves low-temperature reflow (Figure 3), with peak temperatures around 180°C (depending on profile optimization). This is 80°C lower than typical SnAg reflow temperatures. The material demonstrates macro and micro void-free performance even after multiple reflows to form reliable interconnections across various under-bump metallization materials (Figure 4). Finally, SOLDERON BP IN 1000 Indium delivers stable and consistent performance over thermal and electrolytic aging (Figure 5).