Methods and apparatus are disclosed for attaching the integrated circuit (IC) packages to printed circuit boards (PCBs) to form smooth solder joints. A polymer flux may be provided in the process to mount an IC package to a PCB. The polymer flux may be provided on connectors of the IC package, or provided on PCB contact pad and/or pre-solder of the PCB. When the IC package is mounted onto the PCB, the polymer flux may cover a part of the connector, and may extend to cover a surface of the molding compound on the IC package. The polymer flux may completely cover the connector as well. The polymer flux delivers a fluxing component that facilitates smooth solder joint formation as well as a polymer component that offers added device protection by encapsulating individual connectors. The polymer component may be an epoxy.