One-Step Underfill 688 is a low surface tension, single component epoxy resin designed as a one-step no-flow underfill for flip chip, CSP, BGA and micro-BGA assemblies. One-Step Underfill 688 improves assembly reliability through high Tg, low CTE, and good fill with no voiding. Faster throughput and higher yields can be achieved using One-Step Underfill 688 because of its excellent capillary action, fast reflow characteristics, and rapid cure speeds.

One-Step Underfill 688 can be dispensed after solder paste printing, before component placement. The entire assembly is reflowed and cured simultaneously in a standard lead-free reflow process, eliminating the need for a second assembly process and separate cure cycle.

One-Step Underfill 688 wets solder to OSP, ENIG, immersion silver, and immersion tin board surfaces and does not require flux. It is compatible with PAI-AIM’s full line of no clean flux chemistries.