The CN-1751-4 reworkable underfill encapsulant is crack resistant, to withstand flexing experienced by flexible printed circuitry or drops and shocks of very thin printed circuit assemblies. It has a low CTE, 48 ppm/°C for superior thermal cycle performance. Its viscosity is only 900 cps, so it can flow quickly across large BGA's and POP's.
Rework is accomplished by use of elevated temperature, 170° to 180°C, to remove the underfill fillet. Then, the BGA is lifted from the board after heating it to reflow temperature. Underfill residue is easily scraped off, again at 170° to 180°C.(Email for pricing and availability)
Learn more about Zymet