AMTECH SynTECH-LF-TF is a lead-free flux with low activity (L0) for lead-free applications. Formulated for syringe, stencil printing, and rework on all PCB surface finishes, can be used for BGA sphere attachment and reballing, also designed to work on all flip chip bumping and chip scale packaging sites.
To achieve better results with voiding or to reduce tombstoning, as a starting point for process optimization using SynTECH-LF-TF consider longer soaking zone, (170-220°C) for 60-90 seconds, with a rapid pre-heat stage. If there is evidence of solder de-wetting, consider lowering the peak reflow temperature, or reduce the time above liquidus to <60 seconds.
SynTECH-LF-TF can be left on the board for many SMT assemblies. For applications requiring cleaning, SynTECH-LF-TF can be cleaned using commercially available flux residue removers such as INVENTEC Promoclean™ and Promosolv™ cleaning chemistries.
Storage and Handling
Tacky flux should be stored at room temperature (20-25°C). Syringes and cartridges should be stored vertically with the dispensing tip down. Properly stored tacky flux has a 12 month shelf life.